flex_color_scheme.dart

import 'dart:math' as math;

import 'package:flutter/foundation.dart';
import 'package:flutter/material.dart';
import 'package:flutter/services.dart';
import 'package:material_color_utilities/material_color_utilities.dart';

import 'flex_color.dart';
import 'flex_constants.dart';
import 'flex_core_palette.dart';
import 'flex_extensions.dart';
import 'flex_key_color.dart';
import 'flex_scheme.dart';
import 'flex_scheme_color.dart';
import 'flex_scheme_on_colors.dart';
import 'flex_sub_themes.dart';
import 'flex_sub_themes_data.dart';
import 'flex_tones.dart';

// ignore_for_file: comment_references

/// Enum for using predefined surface blend modes for surface and background
/// colors in [FlexColorScheme] based themes.
///
/// The mode [highBackgroundLowScaffold] is the closest equivalent to the style
/// used in [FlexColorScheme] before version 4 via the to be deprecated
/// [FlexSurface] enum property [surfaceStyle] in [FlexColorScheme.light] and
/// [FlexColorScheme.dark] factories.
enum FlexSurfaceMode {
  /// All surfaces have same alpha blend level including scaffold background.
  ///
  /// The blend level is at equal strength as set by blendLevel,
  /// the blend strength mix definition is:
  ///
  /// * Scaffold background, surface, dialogs, background: (1x)
  ///
  /// This mode results in elevation overlay color on [Material] type
  /// [MaterialType.card], [MaterialType.canvas] and [MaterialType.circle]
  /// themed background color in dark theme mode.
  ///
  /// In surface modes that use different blend strengths and blend color,
  /// that differs from the value used for colorScheme.surface,
  /// those [Material] surfaces will not get
  /// elevation overlay color in dark mode, even if set to on. For more
  /// information see issue: https://github.com/flutter/flutter/issues/90353
  level,

  /// Decreasing blend level in order background, surface, scaffold.
  ///
  /// The blend level decreases on surfaces in this order:
  ///
  /// * Background (3/2x)
  /// * Surface & dialogs (1x)
  /// * Scaffold (1/2x)
  ///
  /// Theme colorScheme.primary color is used as blend color on all surfaces.
  ///
  /// In combination with the blend level [FlexColorScheme.blendLevel], it
  /// results in a style where scaffold background has a much lower blend
  /// strength, 1/3x of blend level value and remains mostly unbranded at
  /// low blend levels. Surface uses the blend level value, and
  /// background gets 3/2x the blend level value.
  ///
  /// The mode [FlexSurfaceMode.highBackgroundLowScaffold] can be used to
  /// replace the style that was produced when using old and removed
  /// `FlexColorScheme.surfaceStyle` enum property `FlexSurface` in
  /// [FlexColorScheme.light] and [FlexColorScheme.dark] before version 4.
  ///
  /// The mode [FlexSurfaceMode.highBackgroundLowScaffold] uses the same
  /// design concept as the only style offered via removed `FlexSurface`
  /// in `FlexColorScheme.surfaceStyle` that was in use before version 4,
  /// and deprecated in version 4.2 and removed in version 5.0.0.
  ///
  /// By adjusting the [FlexColorScheme.blendLevel] property and using this
  /// style, you can find a similar visual effect when using
  /// [FlexSurfaceMode.highBackgroundLowScaffold] with the following values when
  /// matching match most prominent blended [ColorScheme.background] color.
  ///
  /// In light theme mode:
  ///
  /// * [FlexSurface.material] 0% : blendLevel = 0
  /// * [FlexSurface.light]    2% : blendLevel = 3...4
  /// * [FlexSurface.medium]   4% : blendLevel = 7
  /// * [FlexSurface.strong]   6% : blendLevel = 10
  /// * [FlexSurface.heavy]    8% : blendLevel = 13...14
  ///
  /// In dark theme mode:
  ///
  /// * [FlexSurface.material] 0% : blendLevel = 0
  /// * [FlexSurface.light]    5% : blendLevel = 8
  /// * [FlexSurface.medium]   8% : blendLevel = 13...14
  /// * [FlexSurface.strong]  11% : blendLevel = 19
  /// * [FlexSurface.heavy]   14% : blendLevel = 23
  ///
  /// Since there is not the same relationship between background and
  /// surface, when using the older [FlexSurface] based style, that uses
  /// individually tuned relationships. The old and new designs do never
  /// align exactly at any blendLevel. The above values produce visually
  /// similar results for the most prominent background color blend.
  ///
  /// To get elevation overlay color in dark themes on all surfaces used by
  /// [Material], use one of the modes where background and dialog color equals
  /// the blend strength on surface color, like [level],
  /// [levelSurfacesLowScaffold], [highScaffoldLowSurfaces],
  /// [levelSurfacesLowScaffoldVariantDialog] and
  /// [highScaffoldLowSurfacesVariantDialog]. Other modes will only use
  /// elevation overlay if their background happens to be equal to resulting
  /// colorScheme.surface color. For more information
  /// see issue: https://github.com/flutter/flutter/issues/90353
  ///
  /// When using very strong surface branding in dark mode, having an overlay
  /// elevation color in dark mode is less critical, since the elevation
  /// becomes partially visible via shadows and the surface may even have
  /// another color tint if using e.g. [levelSurfacesLowScaffoldVariantDialog]
  /// or [highScaffoldLowSurfacesVariantDialog].
  highBackgroundLowScaffold,

  /// Decreasing blend level in order surface, background, scaffold.
  ///
  /// The blend level decreases on surfaces in this order:
  ///
  /// * Surface & dialogs (3/2x)
  /// * Background (1x)
  /// * Scaffold (1/2x)
  ///
  /// Theme colorScheme.primary color is used as blend color on all surfaces.
  ///
  /// To get elevation overlay color in dark themes on all surfaces used by
  /// [Material], use one of the modes where background and dialog color equals
  /// the blend strength on surface color, like [level],
  /// [levelSurfacesLowScaffold], [highScaffoldLowSurfaces] and
  /// [highScaffoldLowSurfaces]. Other modes will only use
  /// elevation overlay if their background happens to be equal to resulting
  /// colorScheme.surface color. For more information
  /// see issue: https://github.com/flutter/flutter/issues/90353
  ///
  /// When using very strong surface branding in dark mode, having an overlay
  /// elevation color in dark mode is less critical, since the elevation
  /// becomes partially visible via shadows and the surface may even have
  /// another color tint if using e.g. [levelSurfacesLowScaffoldVariantDialog]
  /// or [highScaffoldLowSurfacesVariantDialog].
  highSurfaceLowScaffold,

  /// Decreasing blend level in order scaffold, background, surface.
  ///
  /// The blend level decreases on surfaces in this order:
  ///
  /// * Scaffold (3x)
  /// * Background (1x)
  /// * Surface & dialogs (1/2x)
  ///
  /// Theme colorScheme.primary color is used as blend color on all surfaces.
  ///
  /// To get elevation overlay color in dark themes on all surfaces used by
  /// [Material], use one of the modes where background and dialog color equals
  /// the blend strength on surface color, like [level],
  /// [levelSurfacesLowScaffold], [highScaffoldLowSurfaces] and
  /// [highScaffoldLowSurfaces]. Other modes will only use
  /// elevation overlay if their background happens to be equal to resulting
  /// colorScheme.surface color. For more information
  /// see issue: https://github.com/flutter/flutter/issues/90353
  ///
  /// When using very strong surface branding in dark mode, having an overlay
  /// elevation color in dark mode is less critical, since the elevation
  /// becomes partially visible via shadows and the surface may even have
  /// another color tint if using e.g. [levelSurfacesLowScaffoldVariantDialog]
  /// or [highScaffoldLowSurfacesVariantDialog].
  highScaffoldLowSurface,

  /// Decreasing blend level in order scaffold, background, surface.
  ///
  /// The blend level decreases on surfaces in this order:
  ///
  /// * Scaffold (3x)
  /// * Background (3/2x)
  /// * Surface (1x)
  ///
  /// Theme colorScheme.primary color is used as blend color on all surfaces.
  ///
  /// To get elevation overlay color in dark themes on all surfaces used by
  /// [Material], use one of the modes where background and dialog color equals
  /// the blend strength on surface color, like [level],
  /// [levelSurfacesLowScaffold], [highScaffoldLowSurfaces] and
  /// [highScaffoldLowSurfaces]. Other modes will only use
  /// elevation overlay if their background happens to be equal to resulting
  /// colorScheme.surface color. For more information
  /// see issue: https://github.com/flutter/flutter/issues/90353
  ///
  /// When using very strong surface branding in dark mode, having an overlay
  /// elevation color in dark mode is less critical, since the elevation
  /// becomes partially visible via shadows and the surface may even have
  /// another color tint if using e.g. [levelSurfacesLowScaffoldVariantDialog]
  /// or [highScaffoldLowSurfacesVariantDialog].
  highScaffoldLevelSurface,

  /// Decreasing blend level in order background & surface, scaffold.
  ///
  /// The blend level decreases on surfaces in this order:
  ///
  /// * Surface & background (1x)
  /// * Scaffold (1/2x)
  ///
  /// Theme colorScheme.primary color is used as blend color.
  ///
  /// This mode results in elevation overlay color on [Material] type
  /// [MaterialType.card], [MaterialType.canvas] and [MaterialType.circle]
  /// themed background color in dark theme mode. In surface modes that
  /// use different blend strengths and blend color, that differs from the value
  /// used for colorScheme.surface, those [Material] surfaces will not get
  /// elevation overlay color in dark mode, even if set to on. For more
  /// information see issue: https://github.com/flutter/flutter/issues/90353
  levelSurfacesLowScaffold,

  /// Decreasing blend level in order scaffold, background & surface.
  ///
  /// The blend level decreases on surfaces in this order:
  ///
  /// * Scaffold (3x)
  /// * Surface & background (1/2x)
  ///
  /// Theme colorScheme.primary color is used as blend color.
  ///
  /// This mode results in elevation overlay color on [Material] type
  /// [MaterialType.card], [MaterialType.canvas] and [MaterialType.circle]
  /// themed background color in dark theme mode. In surface modes that
  /// use different blend strengths and blend color, that differs from the value
  /// used for colorScheme.surface, those [Material] surfaces will not get
  /// elevation overlay color in dark mode, even if set to on. For more
  /// information see issue: https://github.com/flutter/flutter/issues/90353
  highScaffoldLowSurfaces,

  /// Decreasing blend level in order background & surface, scaffold.
  ///
  /// The blend level decreases on surfaces in this order:
  ///
  /// * Surface, background, dialogs (1x)
  /// * Scaffold (1/2x)
  ///
  /// Theme colorScheme.primary color is used as blend color, but dialog
  /// background color uses theme colorScheme.secondaryContainer as its
  /// blend color.
  ///
  /// This modes results in elevation overlay color on all Material types and
  /// background colors in dark theme mode, except dialogs that do NOT get any
  /// elevation overlay color. This happens because Dialogs use the
  /// colorScheme.tertiary color for their blend color which typically
  /// differs from the primary color used on surface color.
  ///
  /// To get elevation overlay color in dark themes on all surfaces used by
  /// [Material], use one of the modes where background and dialog color equals
  /// the blend strength on surface color, like [level],
  /// [levelSurfacesLowScaffold], [highScaffoldLowSurfaces] and
  /// [highScaffoldLowSurfaces]. Other modes will only use elevation overlay
  /// if their background happens to be equal to resulting
  /// colorScheme.surface color. For more information
  /// see issue: https://github.com/flutter/flutter/issues/90353
  ///
  /// The color scheme secondary variant color is a good place in theme colors
  /// to store a custom color you may want to use for special elements on custom
  /// widgets in your application. The secondary variant color is not used
  /// by default by any widget in Flutter SDK, so it can be assigned a color
  /// without affecting any default color behavior of SDK widgets. If you do so
  /// and want to get some funky dialog blends using this color, you can use
  /// this surface mode.
  levelSurfacesLowScaffoldVariantDialog,

  /// Decreasing blend level in order scaffold, background & surface.
  ///
  /// The blend level decreases on surfaces in this order:
  ///
  /// * Scaffold (3x)
  /// * Surface, background, dialogs (1/2x)
  ///
  /// Theme colorScheme.primary color is used as blend color, but dialog
  /// background uses theme colorScheme.secondaryContainer as its blend color.
  ///
  /// This modes results in elevation overlay color on all Material types and
  /// background colors in dark theme mode, except dialogs that do NOT get any
  /// elevation overlay color. This happens because Dialogs use the
  /// colorScheme.tertiary color for their blend color which typically
  /// differs from the primary color used on surface color.
  ///
  /// To get elevation overlay color in dark themes on all surfaces used by
  /// [Material], use one of the modes where background and dialog color equals
  /// the blend strength on surface color, like [level],
  /// [levelSurfacesLowScaffold], [highScaffoldLowSurfaces] and
  /// [highScaffoldLowSurfaces]. Other modes will only use
  /// elevation overlay if their background happens to be equal to resulting
  /// colorScheme.surface color. For more information
  /// see issue: https://github.com/flutter/flutter/issues/90353
  ///
  /// The color scheme secondary variant color is a good place in theme colors
  /// to store a custom color you may want to use for special elements on custom
  /// widgets in your application. The secondary variant color is not used
  /// by default by any widget in Flutter SDK, so it can be assigned a color
  /// without affecting any default color behavior of SDK widgets. If you do so
  /// and want to get some funky dialog blends using this color, you can use
  /// this surface mode.
  highScaffoldLowSurfacesVariantDialog,

  /// Use your own custom surface and background blend style.
  ///
  /// Use this option and use the [FlexSchemeSurfaceColors.blend] constructor
  /// to make your custom surface colors using the applied blend levels.
  custom,
}

/// Enum to select the used AppBarTheme style in [FlexColorScheme] based themes
/// when using its `light` and `dark` factories.
enum FlexAppBarStyle {
  /// Use the scheme primary color as the AppBar's themed background color.
  ///
  /// This is the default for light themes.
  primary,

  /// Use Material surface color as the AppBar's themed background color.
  ///
  /// This is the default for dark schemes.
  ///
  /// For a dark scheme this choice will result in a near black app bar. If this
  /// setting is used in a light scheme, it will result in a white app bar, as
  /// the standard Material surface color for light scheme is white.
  material,

  /// Use scheme surface color as the the AppBar's themed background color,
  /// including any blend color it may have.
  surface,

  /// Use scheme background color as the the AppBar's themed background color,
  /// including any blend color it may have.
  background,

  /// Use a custom [AppBar] background color as its themed background color.
  ///
  /// If you provide a color value to [FlexColorScheme.appBarBackground]
  /// color directly, it will be used as the themed [AppBar] background color.
  ///
  /// If it is not defined, then the [appBarColor] defined in passed in
  /// [FlexSchemeColor] property [colors] is used when using the
  /// factories [FlexColorScheme.light] and [FlexColorScheme.dark], as the
  /// custom color for the [AppBar] theme.
  ///
  /// The built-in color schemes have the same color value that is assigned to
  /// [FlexSchemeColor.secondaryContainer] also assigned to
  /// [FlexSchemeColor.appBarColor], so with them, the custom choice always
  /// results in the [FlexSchemeColor.secondaryContainer] color, which is same
  /// as output [ColorScheme.secondaryContainer], being used as the [AppBar]
  /// color when using the [custom] choice with them.
  ///
  /// FlexColorSchemes using custom [FlexSchemeColor] can assign any color
  /// to their [FlexSchemeColor.appBarColor] color. It does not have to be
  /// a part of the colors that exist in the standard [ColorScheme].
  ///
  /// If there is no custom color definition in above paths when using the
  /// [custom] style, the [AppBar] color will be same as with [material] choice.
  custom,
}

/// Enum used to define the [SystemUiOverlayStyle] for the system navigation
/// bar.
///
/// Used with the [FlexColorScheme.themedSystemNavigationBar]
/// helper to select the background style of system navigation bar when using
/// the helper in an [AnnotatedRegion] to style the system navigation bar.
enum FlexSystemNavBarStyle {
  /// Standard Android system style, white in light theme and black in
  /// dark theme.
  system,

  /// The system navigation bar will be the same color as active theme
  /// colorScheme.surface color. If your FlexColorScheme definition is set to
  /// use primary branded surface and background colors, the same primary
  /// color blend that the surface color has received will be used.
  surface,

  /// The system navigation bar will be the same color as active theme
  /// colorScheme.background color. If your FlexColorScheme definition is set
  /// to use primary branded surface and background colors, the same primary
  /// color blend that the background color has received will be used.
  background,

  /// The system navigation bar will be the same color as active theme
  /// scaffoldBackground color. If your FlexColorScheme definition is set
  /// to use primary branded surface and background colors, the same primary
  /// color blend that the scaffoldBackground color has received will be used.
  scaffoldBackground,

  /// Make the system navigation bar fully transparent, showing the background,
  /// while navigation buttons float over the background.
  /// For this to work Android SDK has to be >= 29.
  ///
  /// The fully transparent system navigation bar works well when there is a
  /// bottom navigation bar with some opacity, you can then share the same
  /// background as it has with the system navigation bar, using same color
  /// and opacity as on the bottom navigation bar, creating one shared surface
  /// with same color and opacity on bottom navigation bar and the system
  /// navigation bar. The package readme includes on example of this.
  transparent,
}

/// Enum to select [TabBarTheme] preference in [FlexColorScheme] based themes.
enum FlexTabBarStyle {
  /// Themed to fit with active [FlexAppBarStyle] and [AppBarTheme].
  ///
  /// Indicator, text and icons contrast well with AppBar background color,
  /// regardless of chosen [FlexAppBarStyle].
  ///
  /// This is the default style for FlexColorScheme based themes and typically
  /// the style you want.
  forAppBar,

  /// Themed to fit with current background and surface colors.
  ///
  /// Indicator, text and icons contrast with background and surface colors
  /// via primary color.
  ///
  /// If you intend to use your TabBar's only on surfaces, like Scaffold
  /// or in cards using default theme background color, then use this style.
  /// If you use an AppBar theme that is surface colored in both light and dark
  /// theme, then this style will also work well when the TabBar is used
  /// in the AppBar, as well as on surfaces.
  forBackground,

  /// Make a [TabBarTheme] sub-theme that equals the style you get with
  /// ThemeData.from constructor and Widget default values in Flutter SDK.
  ///
  /// This works well with default primary colored AppBar's in light
  /// theme and dark surface colored AppBars or other dark surfaces in dark
  /// theme. It does not work with all app bar styles supported by
  /// [FlexColorScheme], prefer using [forAppBar] for that.
  flutterDefault,

  /// An experimental [TabBarTheme] mode that works on both primary and
  /// background colors.
  ///
  /// This theme is more low contrast than the themes explicitly designed
  /// for their target surface. Use with caution, with some combinations
  /// the style may have poor contrast and look disabled.
  ///
  /// WARNING: This feature is experimental and its resulting style
  /// might be modified to improve it in future versions. Changes to the
  /// produced style will not be considered breaking, only as a fix.
  ///
  /// Prefer using [forAppBar] or [forBackground] depending on where you
  /// primarily intend to use your tab bars.
  universal,
}

/// Make beautiful Flutter themes using pre-designed color schemes or custom
/// colors. Get the resulting [ThemeData] with the [toTheme] method.
///
/// Flutter's [ThemeData.from] is a good starting point for [ColorScheme] based
/// themes. It has a some gaps leaving some properties in the theme
/// to their defaults from the standard [ThemeData] factory constructor, those
/// default values will end up not matching the used [ColorScheme], especially
/// in dark mode themes. [FlexColorScheme] fixes these gaps and makes it much
/// easier to create themes using the color scheme concept.
///
/// You can create the theme using a standard [ColorScheme], but you can also
/// create a theme by just providing a few selected color values, or
/// no color values at all and get defaults. If you provide both a [ColorScheme]
/// and some individual property values that also exist in a [ColorScheme], the
/// individual property values will override the corresponding ones in your
/// [ColorScheme].
///
/// [FlexColorScheme] does not rely on [ThemeData.from] a [ColorScheme] for
/// its implementation. It uses the [ThemeData] factory directly to create the
/// [ThemeData] object from its [FlexColorScheme] data, that is then returned
/// with the [FlexColorScheme.toTheme] getter.
///
/// A more opinionated theme and style can be returned by passing in a default
/// [FlexSubThemesData] () constructor to [subThemesData].
/// By default the sub-themes take inspiration from the Material 3 (M3) Design
/// guide [specification](https://m3.material.io) and uses its values as
/// defaults when it is possible to do so in Flutter
/// SDK theming, within its current Material 2 (M2) design limitations.
///
/// The component sub-themes can configured further by configuring a large
/// amount of properties in [FlexSubThemesData] that is passed into
/// [FlexColorScheme.subThemesData]. A commonly used feature is
/// to adjust the default corner border radius on all sub-themes for widgets
/// that supports it. The opinionated design is also more flat and features
/// primary tinted hover, focus, highlight and splash colors, among other
/// things.
///
/// It can be verbose to define nice color scheme directly with the default
/// unnamed constructor. [FlexColorScheme] is primarily intended to be used
/// with its two factory constructors [FlexColorScheme.light] and
/// [FlexColorScheme.dark], that create nice schemes using defaults and
/// computed color values. The light and dark schemes also give you access
/// to many predefined color schemes that you can use and easily modify.
///
/// With the light and dark factories you can also create
/// beautiful toned themes from just a single color.
/// [FlexColorScheme] makes it easy to create themes that use color branded
/// surfaces (backgrounds), that use alpha blend to mix in a varying degree
/// of a color, typically the primary color, into surfaces and backgrounds.
///
/// Branded surface are described in the Material design guide, but Flutter
/// offers no out of the box help to make such themes. With [FlexColorScheme]
/// you can use a varying degree of surface and background branding levels for
/// any theme you make, both in light and dark mode.
///
/// [FlexColorScheme] makes it easy to make a theme where the [AppBar]
/// themed background color is not tied to primary color in light theme mode or
/// to surface color in dark theme mode, and it can also follow the branded
/// scheme surface or background color.
///
/// [FlexColorScheme] can automatically adjust the [TabBarTheme] to fit with the
/// active [AppBar] background or to be themed to always fit on
/// background/surface colors, if its primary usage will be in e.g. a [Scaffold]
/// body, or [Material] surface or canvas.
///
/// You can also quickly adjust things like the scrim on the app bar in Android
/// with [transparentStatusBar] and tooltip style with
/// [tooltipsMatchBackground].
///
/// The two factory constructors [FlexColorScheme.light] and
/// [FlexColorScheme.dark] also offer support for more advanced and
/// customizable key color generated [ColorScheme]'s, than what is offered out
/// of the box in Flutter SDK via [ColorScheme.fromSeed].
@immutable
class FlexColorScheme with Diagnosticable {
  /// Default constructor that requires [brightness] and four main color scheme
  /// color properties in order to make a fully defined color scheme for
  /// a [ThemeData] object.
  ///
  /// For more convenient usage of [FlexColorScheme] consider using its two
  /// factory constructors [FlexColorScheme.light] and [FlexColorScheme.dark],
  /// that can create schemes using defaults and computed color values, with
  /// custom overrides as needed.
  ///
  /// The two factories also contain additional properties that can be used to
  /// create color branded surfaces, toggle the [AppBarTheme] between a few
  /// styles, and to make dark themes that use true black backgrounds and
  /// surfaces. As well as using [FlexKeyColors] and [FlexTones] to make and
  /// customize key color seed generated [ColorScheme]s.
  const FlexColorScheme({
    this.colorScheme,
    this.brightness,
    this.primary,
    this.primaryContainer,
    @Deprecated('Replaced with `primaryContainer`, after version 4.2.0, '
        'due to deprecation in Flutter master from 2.10.0')
        this.primaryVariant,
    this.secondary,
    this.secondaryContainer,
    @Deprecated('Replaced with `secondaryContainer`, after version 4.2.0, '
        'due to deprecation in Flutter master from 2.10.0')
        this.secondaryVariant,
    this.tertiary,
    this.tertiaryContainer,
    this.error,
    this.surface,
    this.background,
    this.scaffoldBackground,
    this.dialogBackground,
    this.appBarBackground,
    this.onPrimary,
    this.onPrimaryContainer,
    this.onSecondary,
    this.onSecondaryContainer,
    this.onTertiary,
    this.onTertiaryContainer,
    this.onSurface,
    this.onBackground,
    this.onError,
    this.surfaceTint,
    this.tabBarStyle = FlexTabBarStyle.forAppBar,
    this.appBarElevation = 0,
    this.bottomAppBarElevation = 0,
    this.tooltipsMatchBackground = false,
    this.transparentStatusBar = true,
    this.visualDensity,
    this.textTheme,
    this.primaryTextTheme,
    this.fontFamily,
    this.platform,
    this.typography,
    this.applyElevationOverlayColor = true,
    @Deprecated('This property has no function after 4.2.0. FlexColorScheme '
        'opinionated component sub-themes are added by adding a default '
        'constructor FlexSubThemesData() to subThemesData. This creates '
        'sub-themes using the FlexColorScheme opinionated defaults. You can '
        'modify the sub-themes by changing the FlexSubThemesData properties. '
        'This property will be completely removed in version 6.0.0.')
        this.useSubThemes = false,
    this.subThemesData,
    this.useMaterial3 = false,
    this.extensions,
  })  : assert(appBarElevation >= 0.0, 'AppBar elevation must be >= 0.'),
        assert(bottomAppBarElevation >= 0.0,
            'Bottom AppBar elevation must be >= 0.');

  /// The overall [ColorScheme] based colors for the theme.
  ///
  /// This property provides an alternative way to define custom colors for
  /// [FlexColorScheme] and is available from version 4.2.0. It is useful if
  /// you already have a custom [ColorScheme] based color definition that
  /// you want to use with FlexColorScheme theming and its sub-theming
  /// capabilities. This is useful when using fully custom scheme or using the
  /// Material 3 based design and its seed generated color schemes.
  ///
  /// The factories [FlexColorScheme.light] and [FlexColorScheme.dark] provide
  /// convenience factories for also generating M3 based seeded themes using
  /// the built in [ColorSchemes] as seed colors or custom colors you provide
  /// as seeding colors.
  ///
  /// If you provide both a [ColorScheme] and some individual direct property
  /// values that also exist in a [ColorScheme], the individual property values
  /// will override the corresponding ones in your [ColorScheme].
  ///
  /// If you do not define a [colorScheme], the individual color value
  /// properties and their defaults are used to define your effective
  /// [FlexColorScheme] and its resulting [ColorScheme] and [ThemeData].
  ///
  /// The [FlexColorScheme]'s effective [ColorScheme] can be returned with
  /// [toScheme]. This will always get you a complete color scheme, including
  /// calculated and derived color values, which is particularly useful when
  /// using the [FlexColorScheme.light] and [FlexColorScheme.dark] factories
  /// to compute color scheme branded surface colors for you. The effective
  /// [ColorScheme] for your theme is often needed if you want to create custom
  /// sub-themes that should use the colors from the scheme using none default
  /// color assignments computed from the input colors.
  final ColorScheme? colorScheme;

  /// The overall brightness of this color scheme.
  ///
  /// The [Brightness.light] denotes a theme for light theme mode and
  /// [Brightness.dark] a dark theme mode. The colors you define should match
  /// the used [brightness] value in order for the theme to make visual sense.
  ///
  /// If not defined, and if there is no [colorScheme] defined, it defaults
  /// to [Brightness.light].
  final Brightness? brightness;

  /// The color displayed most frequently across your application’s screens and
  /// components.
  ///
  /// If not defined and if there is no [colorScheme] defined, and [brightness]
  /// is [Brightness.light] it defaults to [FlexColor.materialLightPrimary].
  /// If not defined and if there is no [colorScheme] defined, and [brightness]
  /// is [Brightness.dark] it defaults to [FlexColor.materialDarkPrimary].
  final Color? primary;

  /// A color used for elements needing less emphasis than [primary].
  ///
  /// If not defined, and if there is no [colorScheme] defined, the default
  /// result will be [primary] color.
  final Color? primaryContainer;

  /// (Deprecated) A darker version of the primary color.
  ///
  /// In Flutter SDK the `primaryVariant` color is only used by [SnackBar]
  /// button color in dark theme mode as a part of predefined widget behavior.
  /// If you provide a custom [SnackBarThemeData] where you define
  /// [SnackBarThemeData.actionTextColor] to [primary] or [secondary], this
  /// color property becomes a good property to use if you need a custom color
  /// for custom widgets accessible via your application's ThemeData, that is
  /// not used as default color by any other built-in widgets. This applies
  /// to Flutter 2.8.1 and earlier versions.
  ///
  /// The property is deprecated in Flutter SDK and was replaced
  /// by a new property called [primaryContainer]. It is deprecated from
  /// master v2.6.0-0.0.pre, and in stable (2.10.0).
  /// See https://github.com/flutter/flutter/issues/89852.
  ///
  /// If not defined, and if there is no [colorScheme] defined, it will default
  /// to [primary] color.
  @Deprecated('Replaced with `primaryContainer`, after version 4.2.0, '
      'due to deprecation in Flutter master from 2.10.0')
  final Color? primaryVariant;

  /// An accent color that, when used sparingly, calls attention to parts
  /// of your application.
  ///
  /// If not defined, and if there is no [colorScheme] defined, the default
  /// result will be [primary] color.
  final Color? secondary;

  /// A color used for elements needing less emphasis than [secondary].
  ///
  /// If not defined, and if there is no [colorScheme] defined, it will default
  /// to [secondary] color, and if it is not defined either, then [primary].
  final Color? secondaryContainer;

  /// (Deprecated) A darker version of the secondary color.
  ///
  /// In Flutter SDK the `secondaryVariant` color is not used by in any
  /// built-in widgets default themes or predefined widget behavior.
  /// It is an excellent property to use if you need a custom color for
  /// custom widgets accessible via your application's ThemeData, and that is
  /// not used as default color by any built-in widgets. So you are in
  /// Flutter 2.8.1 and earlier version free to set it to whatever color you
  /// need and not affect any built-in widgets theme based colors.
  ///
  /// The property is deprecated in Flutter SDK and was replaced
  /// by a new property called [secondaryContainer]. It is deprecated from
  /// master v2.6.0-0.0.pre, and in stable (2.10.0).
  /// See https://github.com/flutter/flutter/issues/89852.
  ///
  /// If not defined, and if there is no [colorScheme] defining, scheme result
  /// will be [secondary] color, and if it is not defined either then
  /// [primary] color.
  @Deprecated('Replaced with `secondaryContainer`, after version 4.2.0, '
      'due to deprecation in Flutter master from 2.10.0')
  final Color? secondaryVariant;

  /// A color used as a contrasting accent that can balance [primary]
  /// and [secondary] colors or bring heightened attention to an element,
  /// such as an input field.
  ///
  /// If not defined, and if there is no [colorScheme] defined, it will default
  /// to [secondary] color, and if it is not defined either, then [primary].
  final Color? tertiary;

  /// A color used for elements needing less emphasis than [tertiary].
  ///
  /// If not defined, and if there is no [colorScheme] defined, it will default
  /// to [secondary] color, and if it is not defined either, then [primary].
  final Color? tertiaryContainer;

  /// The color to use for input validation errors, for example on
  /// [InputDecoration.errorText].
  ///
  /// If no value is given, and if there is no [colorScheme] defined, it
  /// defaults to [FlexColor.materialLightError] if brightness is light,
  /// and to [FlexColor.materialDarkError] if brightness is dark.
  final Color? error;

  /// The surface (background) color for widgets like [Card] and
  /// [BottomAppBar].
  ///
  /// The color is applied to [ThemeData.cardColor] and [ColorScheme.surface]
  /// in [ThemeData.colorScheme], it is also used by all [Material] of type
  /// [MaterialType.card].
  ///
  /// If no value is given, and if there is no [colorScheme] defined, it
  /// defaults to [FlexColor.materialLightSurface] if brightness is light,
  /// and to [FlexColor.materialDarkSurface] if brightness is dark.
  final Color? surface;

  /// A color that typically appears behind scrollable content.
  ///
  /// The color is applied to [ThemeData.canvasColor] and
  /// [ThemeData.backgroundColor], it is used eg by menu [Drawer] and by all
  /// [Material] of type [MaterialType.canvas].
  ///
  /// If no value is given, and if there is no [colorScheme] defined, it
  /// defaults to [FlexColor.materialLightBackground] if brightness is light,
  /// and to [FlexColor.materialDarkBackground] if brightness is dark.
  final Color? background;

  /// The color of the [Scaffold] background.
  ///
  /// The color is applied to [ThemeData.scaffoldBackgroundColor].
  ///
  /// This color cannot be controlled separately with Flutter's standard
  /// [ColorScheme] only based themes. FlexColorScheme brings back the
  /// possibility to specify it directly when using color scheme based themes.
  ///
  /// If no color is given, it defaults to [background].
  final Color? scaffoldBackground;

  /// The background color of [Dialog] elements.
  ///
  /// The color is applied to [ThemeData.dialogBackgroundColor]. It cannot be
  /// controlled separately with only a [ThemeData.from] a color scheme.
  ///
  /// If no value is given, it defaults to [surface].
  ///
  /// If you assign a background [SchemeColor] to [dialogBackgroundSchemeColor]
  /// in [FlexSubThemesData] and you have opted in on using component sub themes
  /// with [useSubThemes], then its selected scheme color will override this
  /// value.
  final Color? dialogBackground;

  /// Background theme color for the [AppBar].
  ///
  /// This AppBar theme color cannot be controlled separately with only
  /// standard [ThemeData.from] a [ColorScheme]. [FlexColorScheme] enables you
  /// to specify an AppBar theme color that is independent of the primary color
  /// in light theme and in dark mode of the dark theme's dark surface color.
  ///
  /// When you use it, the correct text and icon contrast color is computed and
  /// set automatically based on provided color.
  ///
  /// This AppBar color will also override any scheme color based selection
  /// in active used sub-themes if you have selected on for the AppBar there.
  final Color? appBarBackground;

  /// A color that is clearly legible when drawn on [primary] color.
  ///
  /// To ensure that an app is accessible, a contrast ratio of 4.5:1 for
  /// [primary] and [onPrimary] is recommended. See
  /// <https://www.w3.org/TR/UNDERSTANDING-WCAG20/visual-audio-contrast-contrast.html>.
  ///
  /// If null, and if [colorScheme.onPrimary] is null, the color is derived
  /// from the brightness of the effective primary color, and will be be black
  /// if it is light and white if it is dark.
  final Color? onPrimary;

  /// A color that's clearly legible when drawn on [primaryContainer].
  ///
  /// To ensure that an app is accessible, a contrast ratio between
  /// [primaryContainer] and [onPrimaryContainer] of at least 4.5:1
  /// is recommended. See
  /// <https://www.w3.org/TR/UNDERSTANDING-WCAG20/visual-audio-contrast-contrast.html>.
  ///
  /// If null, and if [colorScheme.onPrimaryContainer] is null, the color
  /// will via [ColorScheme] default be equal to resulting color scheme
  /// [ColorScheme.onPrimary].
  final Color? onPrimaryContainer;

  /// A color that is clearly legible when drawn on [secondary] color.
  ///
  /// To ensure that an app is accessible, a contrast ratio of 4.5:1 for
  /// [secondary] and [onSecondary] is recommended. See
  /// <https://www.w3.org/TR/UNDERSTANDING-WCAG20/visual-audio-contrast-contrast.html>.
  ///
  /// If null, the on color is derived from the brightness of the [secondary]
  /// color, and will be be black if it is light and white if it is dark.
  final Color? onSecondary;

  /// A color that's clearly legible when drawn on [secondaryContainer].
  ///
  /// To ensure that an app is accessible, a contrast ratio between
  /// [secondaryContainer] and [onSecondaryContainer] of at least 4.5:1
  /// is recommended. See
  /// <https://www.w3.org/TR/UNDERSTANDING-WCAG20/visual-audio-contrast-contrast.html>.
  ///
  /// If null, and if [colorScheme.onSecondaryContainer] is null, the color
  /// will via [ColorScheme] default be equal to resulting color scheme
  /// [ColorScheme.onSecondary].
  final Color? onSecondaryContainer;

  /// A color that's clearly legible when drawn on [tertiary].
  ///
  /// To ensure that an app is accessible, a contrast ratio between
  /// [tertiary] and [onTertiary] of at least 4.5:1 is recommended. See
  /// <https://www.w3.org/TR/UNDERSTANDING-WCAG20/visual-audio-contrast-contrast.html>.
  ///
  /// If null, and if [colorScheme.onTertiary] is null, the color
  /// will via [ColorScheme] default be equal to resulting color scheme
  /// [ColorScheme.onSecondary].
  final Color? onTertiary;

  /// A color that's clearly legible when drawn on [tertiaryContainer].
  ///
  /// To ensure that an app is accessible, a contrast ratio between
  /// [tertiaryContainer] and [onTertiaryContainer] of at least 4.5:1 is
  /// recommended. See
  /// <https://www.w3.org/TR/UNDERSTANDING-WCAG20/visual-audio-contrast-contrast.html>.
  ///
  /// If null, and if [colorScheme.onTertiaryContainer] and [onTertiary) is
  /// null, the color will via [ColorScheme] default be equal to resulting
  /// color scheme [ColorScheme.onSecondary].
  final Color? onTertiaryContainer;

  /// A color that is clearly legible when drawn on [surface] color.
  ///
  /// To ensure that an app is accessible, a contrast ratio of 4.5:1 for
  /// [surface] and [onSurface] is recommended. See
  /// <https://www.w3.org/TR/UNDERSTANDING-WCAG20/visual-audio-contrast-contrast.html>.
  ///
  /// If null, the on color is derived from the brightness of the [surface]
  /// color, and will be be black if it is light and white if it is dark.
  final Color? onSurface;

  /// A color that is clearly legible when drawn on [background] color.
  ///
  /// To ensure that an app is accessible, a contrast ratio of 4.5:1 for
  /// [background] and [onBackground] is recommended. See
  /// <https://www.w3.org/TR/UNDERSTANDING-WCAG20/visual-audio-contrast-contrast.html>.
  ///
  /// If null, the on color is derived from the brightness of the [background]
  /// color, and will be be black if it is light and white if it is dark.
  final Color? onBackground;

  /// A color that is clearly legible when drawn on [error] color.
  ///
  /// To ensure that an app is accessible, a contrast ratio of 4.5:1 for [error]
  /// and [onError] is recommended. See
  /// <https://www.w3.org/TR/UNDERSTANDING-WCAG20/visual-audio-contrast-contrast.html>.
  ///
  /// If null, the on color is derived from the brightness of the [error]
  /// color, and will be be black if it is light and white if it is dark.
  final Color? onError;

  /// A color used as an overlay on a surface color to indicate a component's
  /// elevation.
  ///
  /// You can use this property for convenience if you want to override the
  /// color that this scheme color gets via the factory behavior.
  /// If a [colorScheme] was provided where this corresponding color is
  /// defined, this color property will override the same color in it.
  ///
  /// This color is used by M3 for colored elevation, it is also used as the
  /// blend  color for FlexColorScheme surface blends.
  ///
  /// If undefined it defaults to [primary] color.
  final Color? surfaceTint;

  /// Select preferred style for the default [TabBarTheme].
  ///
  /// By default the TabBarTheme is made to fit with the style of the AppBar,
  /// via default value [FlexTabBarStyle.forAppBar].
  ///
  /// When setting this to [FlexTabBarStyle.forBackground], it will default
  /// to a theme that uses the color scheme and fits on background color,
  /// which typically also on works surface and scaffoldBackground color.
  /// This TabBarTheme style is useful if you primarily intended to use the
  /// TabBar in a Scaffold, Dialog, Drawer or Side panel on their background
  /// colors.
  final FlexTabBarStyle tabBarStyle;

  /// The themed elevation for the [AppBar].
  ///
  /// Defaults to 0, cannot be null.
  ///
  /// The 0 elevation is an iOs style influenced opinionated choice, but it
  /// can easily be adjusted for the theme with this property.
  final double appBarElevation;

  /// The themed elevation for the bottom app bar.
  ///
  /// Defaults to 0, cannot be null.
  ///
  /// The 0 default is so it matches the themed app bar elevation default,
  /// but it can easily be adjusted for the theme with this property.
  final double bottomAppBarElevation;

  /// When `true`, tooltip background color will match the brightness of the
  /// theme's background color.
  ///
  /// By default Flutter's Material tooltips use a theme where the tooltip
  /// background color brightness is inverted in relation to the overall
  /// theme's background color.
  ///
  /// [FlexColorScheme] allows you to use a single toggle to invert this.
  /// Light tooltips on light background is e.g. the default style on
  /// Windows Desktop. You can use this toggle to use this style, or use it as
  /// a means to create a platform adaptive tooltip style, where the
  /// Material and Flutter style is used on devices and Web, but the inverted
  /// scheme is used on desktop platforms.
  ///
  /// Defaults to false, and uses same background style as Material Design guide
  /// and Flutter.
  ///
  /// Regardless of value used on this property, the tooltip theme created by
  /// [FlexColorScheme] does deviate a bit from Flutter's default tooltip theme.
  /// With default Material text theme, it uses a slightly larger font 12dp, for
  /// improved legibility on web and desktop with device pixel ratio 1.0, and
  /// it also uses a padding style suitable for multiline tooltips.
  ///
  /// Default tooltip theme in Flutter Material 2 is currently a bit flawed on
  /// desktop and web, because it defaults to using a very small font (10 dp).
  /// See issue: https:///github.com/flutter/flutter/issues/71429.
  /// Material 3 changes the default tooltip theme size to 11dp.
  final bool tooltipsMatchBackground;

  /// When `true`, the status bar on Android will be the same color as
  /// the rest of the AppBar.
  ///
  /// Defaults to true.
  ///
  /// When true, the AppBar in Android mimics the look of one-toned AppBar's
  /// typically used on iOS. Set it to `false` to revert back and use
  /// Android's default two-toned look. If true the status bar area is also
  /// transparent, then if the app bar is also translucent, content that scrolls
  /// behind it is also visible behind the status bar area.
  final bool transparentStatusBar;

  /// The density value for specifying the compactness of various UI components.
  ///
  /// Consider using [FlexColorScheme.comfortablePlatformDensity].
  /// It is similar to [VisualDensity.adaptivePlatformDensity], but the
  /// density for desktop and Web is less dense in order to offer a bit larger
  /// touch friendly surfaces, but not quite as large as small touch devices.
  ///
  /// This is the same property as in [ThemeData] factory, it is just
  /// passed along to it. Included for convenience to avoid a copyWith if
  /// to change it.
  ///
  /// Density, in the context of a UI, is the vertical and horizontal
  /// "compactness" of the elements in the UI. It is unit less, since it means
  /// different things to different UI elements. For buttons, it affects the
  /// spacing around the centered label of the button. For lists, it affects the
  /// distance between baselines of entries in the list.
  ///
  /// Typically, density values are integral, but any value in range may be
  /// used. The range includes values from [VisualDensity.minimumDensity] (which
  /// is -4), to [VisualDensity.maximumDensity] (which is 4), inclusive, where
  /// negative values indicate a denser, more compact, UI, and positive values
  /// indicate a less dense, more expanded, UI. If a component doesn't support
  /// the value given, it will clamp to the nearest supported value.
  ///
  /// The default for visual densities is zero for both vertical and horizontal
  /// densities, which corresponds to the default visual density of components
  /// in the Material Design specification.
  ///
  /// As a rule of thumb, a change of 1 or -1 in density corresponds to 4
  /// logical pixels. However, this is not a strict relationship since
  /// components interpret the density values appropriately for their needs.
  ///
  /// A larger value translates to a spacing increase (less dense), and a
  /// smaller value translates to a spacing decrease (more dense).
  ///
  /// Defaults to [VisualDensity.adaptivePlatformDensity].
  final VisualDensity? visualDensity;

  /// Text with a color that contrasts with background, surface, card and
  /// canvas colors.
  final TextTheme? textTheme;

  /// A text theme that contrasts with the primary color.
  final TextTheme? primaryTextTheme;

  /// Name of the font family to use as default for the theme.
  final String? fontFamily;

  /// The platform adaptive widgets should adapt to target and mechanics too.
  ///
  /// Same property as in [ThemeData] factory. Included for convenience to
  /// avoid a copyWith to change it.
  ///
  /// Defaults to the current platform, as exposed by [defaultTargetPlatform].
  /// This should be used in order to style UI elements according to platform
  /// conventions.
  ///
  /// Widgets from the material library should use this getter (via [Theme.of])
  /// to determine the current platform for the purpose of emulating the
  /// platform behavior (e.g. scrolling or haptic effects). Widgets and render
  /// objects at lower layers that try to emulate the underlying platform
  /// platform can depend on [defaultTargetPlatform] directly, or may require
  /// that the target platform be provided as an argument. The
  /// [dart.io.Platform] object should only be used directly when it's critical
  /// to actually know the current platform, without any overrides possible (for
  /// example, when a system API is about to be called).
  ///
  /// In a test environment, the platform returned is [TargetPlatform.android]
  /// regardless of the host platform. (Android was chosen because the tests
  /// were originally written assuming Android-like behavior, and we added
  /// platform adaptations for other platforms later). Tests can check behavior
  /// for other platforms by setting the [platform] of the [Theme] explicitly to
  /// another [TargetPlatform] value, or by setting
  /// [debugDefaultTargetPlatformOverride].
  final TargetPlatform? platform;

  /// The color and geometry [TextTheme] values used to configure [textTheme].
  ///
  /// Same property as in [ThemeData] factory. Included for convenience to
  /// avoid a copyWith to change it.
  ///
  /// Included for convenience to avoid a copyWith if it needs to be changed.
  /// Default value deviates from the Flutter standard that uses the old
  /// [Typography.material2014], in favor of newer [Typography.material2018]
  /// as default typography if one is not provided.
  ///
  /// Never mix different [Typography] in light and dark theme mode. If you
  /// do, lerp between dark and light theme mode will fail due Flutter SDK
  /// not being able to handle the use case. See issue:
  /// https://github.com/flutter/flutter/issues/89947
  ///
  /// If you use a default light or
  /// dark Flutter ThemeData() and a FlexColorScheme.toTheme() ThemeData for
  /// the other mode, you must set either the default ThemeData to
  /// [Typography.material2018] OR the [FlexColorScheme.typography] to
  /// [Typography.material2014] to avoid this issue. It is not generally
  /// recommended to create your light and dark theme data with
  /// different methods. If you use FlexColorScheme, DO use it for both the
  /// light and dark theme mode.
  final Typography? typography;

  /// Apply a semi-transparent overlay color on Material surfaces to indicate
  /// elevation for dark themes.
  ///
  /// Same property as in [ThemeData] factory. Included for convenience to
  /// avoid a copyWith to change it.
  ///
  /// In FlexColorScheme it defaults to true. In Flutter [ThemeData.from] it
  /// also default to true, but in [ThemeData] factory it defaults to false.
  ///
  /// Material drop shadows can be difficult to see in a dark theme, so the
  /// elevation of a surface should be portrayed with an "overlay" in addition
  /// to the shadow. As the elevation of the component increases, the
  /// overlay increases in opacity. The [applyElevationOverlayColor] turns the
  /// application of this overlay on or off for dark themes.
  ///
  /// If true and [brightness] is [Brightness.dark], a
  /// semi-transparent version of [ColorScheme.onSurface] will be
  /// applied on top of [Material] widgets that have a [ColorScheme.surface]
  /// color. The level of transparency is based on [Material.elevation] as
  /// per the Material Dark theme specification.
  ///
  /// If false the surface color will be used unmodified.
  ///
  /// Defaults to false in order to maintain backwards compatibility with
  /// apps that were built before the Material Dark theme specification
  /// was published. New apps should set this to true for any themes
  /// where [brightness] is [Brightness.dark].
  ///
  /// See also:
  ///
  ///  * [Material.elevation], which effects the level of transparency of the
  ///    overlay color.
  ///  * [ElevationOverlay.applyOverlay], which is used by [Material] to apply
  ///    the overlay color to its surface color.
  ///  * <https://material.io/design/color/dark-theme.html>, which specifies how
  ///    the overlay should be applied.
  ///
  /// Known limitations:
  ///
  /// Because of how the overlay color application is implemented in Flutter
  /// SDK, you will only get overlay color applied in dark mode when this value
  /// is true, if the [Material] surface color being elevated is equal to
  /// [ThemeData.colorScheme] and its [ColorScheme.surface] color value.
  ///
  /// Thus when using color branded surfaces, if you want all [Material]
  /// surfaces in your theme to get an overlay color in dark mode, you must for
  /// dark themes only use background colors that are equal to the surface
  /// color. Thus when using [FlexColorScheme.dark], use a [FlexSurfaceMode]
  /// that starts with `equal`. That said, if you use heavy color branding,
  /// some surfaces may not need any overlay color, so the
  /// lack of it might not be an issue with other modes in such themes.
  /// For more information about this limitation, see Flutter SDK issue:
  /// https://github.com/flutter/flutter/issues/90353
  final bool applyElevationOverlayColor;

  /// This property has no function after 4.2.0. Prior to version 5 this
  /// property was used to activate the opinionated component sub-themes.
  /// Starting with version 5 they are now enabled by adding a default
  /// constructor `FlexSubThemesData()` to [subThemesData].
  ///
  /// Defaults to false.
  ///
  /// This property will be completely removed in version 6.0.0.
  @Deprecated('This property has no function after 4.2.0. FlexColorScheme '
      'opinionated component sub-themes are added by adding a default '
      'constructor FlexSubThemesData() to subThemesData. This creates '
      'sub-themes using the FlexColorScheme opinionated defaults. You can '
      'modify the sub-themes by changing the FlexSubThemesData properties. '
      'This property will be completely removed in version 6.0.0.')
  final bool useSubThemes;

  /// Activate using FlexColorScheme opinionated component sub-themes by
  /// passing in a default `FlexSubThemesData()`.
  ///
  /// To further configure the sub-themes, change the simple flat value
  /// properties as desired in `FlexSubThemesData()`.
  ///
  /// By default [FlexThemeData.light], [FlexThemeData.dark] and
  /// [FlexColorScheme.toTheme], do as little as they need to just
  /// provide a consistent Material 2 color schemed theme. The additions they
  /// do are described in [FlexColorScheme.toTheme].
  ///
  /// The original purpose of the opinionated sub-themes was to make it easy
  /// to add themed corner radius to all Widgets that support it, and to
  /// provide a consistent look on all buttons, including [ToggleButtons].
  ///
  /// Therefore the sub themes are a convenient way to opt-in on customized
  /// corner radius on Widgets using above themes. By opting in you can set
  /// corner radius for all covered Widgets to same corner radius in one go.
  /// There are also properties to override the global default for each widget
  /// to set different rounding per widget if so desired.
  ///
  /// By default, if a `defaultRadius` is not specified, each widgets corner
  /// radius and some other styling take inspiration from the Material 3 (M3)
  /// specification https://m3.material.io/ and uses its specifications as
  /// defaults when it is possible to do so in Flutter SDK theming, within
  /// its current Material 2 (M2) design limitations.
  ///
  /// In version 5, by opting in via a default [subThemesData] you
  /// get an extensive set of widget component sub themes applied.
  /// They can be customized via the [subThemesData] property, that has
  /// quick and flat sub theme configuration values in the data class
  /// [FlexSubThemesData].
  ///
  /// Opinionated sub themes are provided for:
  ///
  /// * [TextButton]
  /// * [ElevatedButton]
  /// * [OutlinedButton]
  /// * Older buttons using [ButtonThemeData]
  /// * [ToggleButtons]
  /// * [Switch]
  /// * [Checkbox]
  /// * [Radio]
  /// * [InputDecoration]
  /// * [FloatingActionButton]
  /// * [Chip]
  /// * [Card]
  /// * [PopupMenuButton]
  /// * [Dialog]
  /// * [TimePickerDialog]
  /// * [SnackBar]
  /// * [Tooltip]
  /// * [BottomSheet]
  /// * [BottomNavigationBar]
  /// * [NavigationBar]
  /// * [NavigationRail]
  ///
  /// * The custom [ButtonTextTheme] even still provides matching styling to
  ///   for the deprecated legacy buttons if they are used.
  ///
  /// Defaults to null, resulting in FlexColorScheme not using any extra
  /// sub-theming in addition to those described in [FlexColorScheme.toTheme].
  final FlexSubThemesData? subThemesData;

  /// A temporary flag used to opt-in to new SDK Material 3 features.
  ///
  /// Flutter SDK 3.0.5 [useMaterial3] documentation:
  /// -----------------------------------------------
  /// If true, then components that have been migrated to Material 3 will
  /// use new colors, typography and other features of Material 3.
  /// If false, they will use the Material 2 look and feel.
  ///
  /// If a [ThemeData] is constructed with [useMaterial3] set to true, then
  /// some properties will get special defaults. However, just copying a
  /// [ThemeData] with [useMaterial3] set to true will not change any of
  /// these properties in the
  /// resulting [ThemeData]. These properties are:
  /// <style>table,td,th { border-collapse: collapse; padding: 0.45em; }
  /// td { border: 1px solid }</style>
  ///
  /// | Property        | Material 3 default           | Fallback default  |
  /// | :-------------- | :--------------------------- | :---------------- |
  /// | [typography] | [Typography.material2021] | [Typography.material2014] |
  /// | [splashFactory] | [InkSparkle]* or [InkRipple] | [InkSplash]       |
  ///
  /// \* if and only if the target platform is Android and the app is not
  /// running on the web, otherwise it will fallback to [InkRipple].
  ///
  /// During the migration to Material 3, turning this on may yield
  /// inconsistent look and feel in your app. Some components will be migrated
  /// before others and typography changes will be coming in stages.
  ///
  /// [useMaterial3] defaults to false. After all the migrated components
  /// have landed on stable, we will change this to be true by default. After
  /// that change has landed on stable, we will deprecate this flag and remove
  /// all uses of it. Everything will use the Material 3 look and feel at
  /// that point.
  ///
  /// Components that have been migrated to Material 3 are:
  ///
  ///   * [AlertDialog]
  ///   * [AppBar]
  ///   * [Card]
  ///   * [Dialog]
  ///   * [ElevatedButton]
  ///   * [FloatingActionButton]
  ///   * [Material]
  ///   * [NavigationBar]
  ///   * [NavigationRail]
  ///   * [OutlinedButton]
  ///   * [StretchingOverscrollIndicator], replacing the
  ///     [GlowingOverscrollIndicator]
  ///   * [TextButton]
  ///
  /// See also:
  ///
  ///   * [Material Design 3](https://m3.material.io).
  ///
  /// While the migration of Flutter SDK to the Material 3 design spec is
  /// in progress, setting [useSubThemes] in [FlexColorScheme] to true,
  /// will also produce widget sub-themes using current Flutter Material 2
  /// theming limitations. By default these opinionated sub-themes also
  /// implement the Material 3 design and look when it is possible within
  /// current SDK limits. During SDK transition to full M3 support, keeping
  /// useMaterial3 false and just using the FlexColorScheme sub-theming, may
  /// be preferred since it has fewer transitional issues.
  final bool useMaterial3;

  /// Arbitrary additions to this theme.
  ///
  /// This is the same property as [extensions] in ThemeData, it is provided
  /// as a convenience pass-through to ThemeData.
  ///
  /// To define extensions, pass an [Iterable] containing one or more
  /// [ThemeExtension] subclasses to [ThemeData.new] or [copyWith].
  ///
  /// To obtain an extension, use ThemeData.of(context).extension.
  final Iterable<ThemeExtension<dynamic>>? extensions;

  //****************************************************************************
  //
  // LIGHT COLOR SCHEME AND THEME DEFINITIONS
  //
  // Factory FlexColorScheme.light
  //
  //****************************************************************************

  /// Creates a [FlexColorScheme] for light theme mode.
  ///
  /// The factory has no required [FlexSchemeColor] properties, but typically
  /// a [FlexScheme] enum [scheme] value would be provided to use a pre-defined
  /// color scheme.
  ///
  /// As a second alternative the [FlexSchemeColor] class [colors] property
  /// can be used to define custom scheme colors, that can be created with just
  /// one color property by using the factory [FlexSchemeColor.from].
  ///
  /// As a third option you can provide a complete [ColorScheme] in
  /// [colorScheme] and the custom colors for the theme will be based on that
  /// scheme. Since this is the light theme factory the brightness value in used
  /// [colorScheme] is ignored and resulting effective theme and color scheme
  /// will always be light. Make sure you use colors in your color scheme that
  /// are actually colors for a light theme.
  ///
  /// The factory can produce blended surface colors, and also has other
  /// parameters that may impact the effective color scheme used by final theme,
  /// even when a [colorScheme] are provided. The [FlexColorScheme.toScheme]
  /// will give you the effective color scheme that will also be used
  /// when producing [ThemeData] from [FlexColorScheme] and its factories
  /// with [FlexColorScheme.toTheme].
  ///
  /// The factory contains a large number of other properties that can be used
  /// to create beautiful themes by just adjusting a few behavior properties.
  ///
  /// To activate using opinionated sub themes that further refines the produced
  /// theme, set [useSubThemes] to true and optionally pass in a
  /// [FlexSubThemesData] to [subThemesData] to use short cut properties to
  /// setup additional features in the sub-themes.
  ///
  /// Material 3 guide introduces a new color system with key colors and tonal
  /// palettes, see
  /// https://m3.material.io/styles/color/the-color-system/key-colors-tones.
  ///
  /// You can opt-in on using this new M3 color system by creating your tonal
  /// theme colors using the effective [primary], [secondary] and [tertiary]
  /// colors in the factory, as key colors to create tonal palettes for
  /// these main Material 3 color palettes.
  /// Colors from these key color seed generated palettes will then be used as
  /// color tones for the produce [ColorScheme], as defined by the Material 3
  /// design guide. By studying the Flutter SDK [ColorScheme.from] factory you
  /// can see which color tone from what key color is used where.
  /// [FlexColorScheme] uses the same assignments for the tones to the
  /// generated [ColorScheme] when you opt in using Material 3 tonal palettes.
  ///
  /// The [FlexColorScheme] light and dark factory offer more control over the
  /// seed generation setup. With [ColorScheme.from] you can only generate the
  /// [ColorScheme] from one key color, the primary color. With
  /// [FlexColorScheme] factories  you can use separate key colors for
  /// [secondary] and [tertiary] from the [primary] color, to make their
  /// tonal palettes. The effective colors in your [FlexColorScheme] for these
  /// color properties are used as key color inputs when you provide a
  /// [FlexKeyColors] via [keyColors] and enable it by setting
  /// [FlexKeyColors.useKeyColors] to true, which it is in its default
  /// constructor, so to enable it you can just pass in a default
  /// FlexKeyColors() to [keyColors].
  ///
  /// By setting [FlexKeyColors.useSecondary] or
  /// [FlexKeyColors.useTertiary] to false, the corresponding effective colors
  /// in [FlexColorScheme] will not be used as keys for corresponding
  /// [TonalPalette]. If one is off, its tonal palette will instead be based on
  /// the primary color as key. If both are false, the [FlexColorScheme.light]
  /// seeding algorithm becomes the same as using [ColorScheme.from]. The
  /// primary color is always used as seed color when key color seeding is
  /// enabled with [FlexKeyColors.useKeyColors] set to true.
  ///
  /// You can also opt to keep selected effective main colors, primary,
  /// secondary, tertiary and their containers, in your [FlexColorScheme] as
  /// their effective color, even when you enable key color based
  /// seeded tonal palette based ColorScheme output. You do this by
  /// setting [FlexKeyColors.keepPrimary], [FlexKeyColors.keepSecondary] etc to
  /// true, for each color property where you want to keep its exact color value
  /// as defined, but otherwise may be OK with using key seeded color values.
  ///
  /// You can use this feature if you for example want to use an exact
  /// predefined primary brand color in light mode, but are OK with all other
  /// colors using tones derived from its Material 3 tonal palette.
  ///
  /// When you use key color based seeded theme generation, the used key inputs
  /// for primary, secondary and tertiary are only used to set and generate the
  /// tone of the palette used for each colors tonal palette. You will rarely
  /// see the same color on that actual, primary, secondary and tertiary color
  /// in the produced [ColorScheme], unless you lock them down with the "keep"
  /// properties.
  ///
  /// The same tonal palette should typically be used for both
  /// light and dark mode colors. Under the hood [FlexColorScheme] selects the
  /// right color tone from the tonal palette, which is different for light and
  /// dark mode. For a matched light and dark theme, you should use the same
  /// input key color. When you use [FlexColorScheme.light] and
  /// [FlexColorScheme.dark] and the [FlexScheme] enum based [scheme] property,
  /// to use a built-in color scheme, it automatically uses also its
  /// predefined light theme mode defined colors as the key colors for
  /// primary, secondary and tertiary in dark mode, to ensure that the produced
  /// [ColorScheme] is using same tonal palette, but only different tones from
  /// it  for light and dark mode.
  ///
  /// When you use [colors], [colorScheme] or direct override color properties
  /// [primary], [secondary] or [tertiary] in the factories, these effective
  /// colors are used directly as key color inputs. It is then up to
  /// you to decide and design if you use the same key color for tonal palette
  /// generation in light and dark mode.
  ///
  /// If you use [colorScheme] or pass in [primary], [secondary] or
  /// [tertiary], and enable using [keyColors] the generated scheme will first
  /// use color from passed in direct color properties [primary], [secondary]
  /// or [tertiary], as key colors, then the same ones from the passed in
  /// [colorScheme] when it generates the output [ColorScheme] using the active
  /// [FlexKeyColors] setup.
  ///
  /// The generated [ColorScheme]'s properties will override all color
  /// properties that were passed in  via a [colorScheme], except those locked
  /// via the `keep` properties in [FlexKeyColors].
  ///
  /// If you assign override colors via direct color properties for the main
  /// colors [primary], [secondary] or [tertiary] and their containers, they
  /// will also only override the generated resulting [ColorScheme] if the
  /// the `keep` properties are set in [FlexKeyColors]. Other color properties
  /// that exist as both direct color properties and as a color in the
  /// generated resulting [ColorScheme], will always override the generated
  /// color property if they are assigned.
  ///
  /// Normally if you provide an entire [colorScheme] to [FlexColorScheme] it
  /// is typically because you already have a scheme that you want to use as is,
  /// then don't enable [keyColors] or any blends. It is however possible to
  /// apply both blends to passed in [colorScheme] surfaces or to just use
  /// the [primary], [secondary] or [tertiary] colors in passed in [colorScheme]
  /// as [keyColors] to generate an entirely new [ColorScheme] from the passed
  /// in colors, using [primary], [secondary] or [tertiary] as keys.
  factory FlexColorScheme.light({
    /// The [FlexSchemeColor] that will be used to create the light
    /// [FlexColorScheme].
    ///
    /// You can use predefined [FlexSchemeColor] values from [FlexColor] or
    /// [FlexColor.schemes] map or define your own colors with
    /// [FlexSchemeColor] or [FlexSchemeColor.from].
    ///
    /// For using built-in color schemes, the convenience shortcut to select
    /// it with the [scheme] property is recommended and leaving [colors]
    /// undefined. If both are specified the scheme colors defined by [colors]
    /// are used. If both are null then [scheme] defaults to
    /// [FlexScheme.material], thus defining the resulting scheme.
    final FlexSchemeColor? colors,

    /// Use one of the built-in color schemes defined by enum [FlexScheme].
    ///
    /// Give it one of the enum values to use the scheme, like eg.
    /// [FlexScheme.mandyRed].
    ///
    /// To create custom color schemes use the [colors] property. If both
    /// [colors] and [scheme] are specified, the scheme defined by
    /// [colors] is used. If both are null, then [scheme] defaults to
    /// [FlexScheme.material].
    final FlexScheme? scheme,

    /// The overall [ColorScheme] based colors for the theme.
    ///
    /// This property provides a new way to define custom colors for
    /// [FlexColorScheme] and is available from version 4.2.0. It is useful if
    /// you already have a custom [ColorScheme] based color definition that
    /// you want to use with FlexColorScheme theming and its sub-theming
    /// capabilities.
    ///
    /// If you provide both a [ColorScheme] and some individual direct property
    /// values that also exist in a [ColorScheme], the individual property
    /// values will override the corresponding ones in your [ColorScheme].
    ///
    /// If you do not define a [colorScheme], the used colors will be determined
    /// by the [colors] and [scheme] properties. However, when a [colorScheme]
    /// is defined it takes precedence. The [brightness] in the provided
    /// [colorScheme] is always ignored and set to [Brightness.light] since this
    /// is the light theme mode factory. Make sure the colors used in your color
    /// scheme are intended for a light theme.
    ///
    /// If you define a [surfaceMode] and set [blendLevel] > 0, then [surface]
    /// and [background] colors in the provided [colorScheme] will be overridden
    /// by the computed color branded surfaces. If your [colorScheme] already
    /// contains branded surface colors, then keep [blendLevel] = 0 to continue
    /// using them.
    ///
    /// If you use [lightIsWhite] factory feature, it will also override your
    /// [colorScheme] based [surface] and [background] properties and make them
    /// 8% lighter.
    ///
    /// If you opt in on using sub themes with [useSubThemes] and have set
    /// [subThemesData.blendOnColors] to true and have defined [surfaceMode]
    /// and set [blendLevel] > 0, then the effective color scheme based on
    /// colors onPrimary, onSecondary, onError, onSurface and onBackground will
    /// be changed accordingly too.
    ///
    /// The [colorScheme] colors are also included and affected by factory
    /// properties [usedColors] and [swapColors] and included in their behavior.
    ///
    /// The [FlexColorScheme]'s effective [ColorScheme] can be returned with
    /// [toScheme]. This will always get you a complete color scheme, including
    /// calculated and derived color values, which is particularly useful when
    /// using the [FlexColorScheme.light] and [FlexColorScheme.dark] factories
    /// to compute color scheme branded surface colors for you. The effective
    /// [ColorScheme] for your theme is often needed if you want to create
    /// custom sub-themes that should use the colors from the scheme using none
    /// default color assignments from the color scheme.
    final ColorScheme? colorScheme,

    /// The number of the six main scheme colors to be used when creating
    /// effective [ColorScheme].
    ///
    /// This is a convenience property that allows you to vary which colors to
    /// use of the primary, secondary and tertiary colors and their container
    /// colors when FlexSchemeColor creates its effective [ColorScheme] from
    /// the input colors. The integer number corresponds to using:
    ///
    /// * 1 = Only the primary color
    /// * 2 = Primary & Secondary colors
    /// * 3 = Primary + container & Secondary colors
    /// * 4 = Primary + container & Secondary + container
    /// * 5 = Primary + container & Secondary + container & tertiary colors
    /// * 6 = Primary + container & Secondary + container & tertiary + container
    ///
    /// By default the value is 6 and all main scheme colors in
    /// `FlexSchemeColor` are used.
    ///
    /// When the value is 1, the result is the same as if we would have
    /// created the colors with [FlexSchemeColor.from] by only giving it the
    /// required primary color. With 2, it is equivalent to as if we would have
    /// given it only the primary and secondary colors, and so on.
    /// This property makes it possible to simulate and change the resulting
    /// [FlexColorScheme] to as if you would have specified 1, 2, 3 ... 6 of
    /// the colors. If your used [FlexColorScheme] `colors` was actually created
    /// with [FlexSchemeColor.from] with only the primary color defined, then
    /// changing the value from 6 ... 3, 2 or 1, will all produce the same
    /// effective scheme as the computed values will be the same as the
    /// [FlexSchemeColor.from] is using to compute any main missing scheme
    /// color values.
    final int usedColors = 6,

    /// Blends theme colors into surfaces and backgrounds.
    ///
    /// If defined, used mode overrides the older [surfaceStyle]
    /// property setting. Prefer using [surfaceMode] over [surfaceStyle],
    /// it offers more color branded surface modes and separate control over
    /// the used branding level via the separate [blendLevel] property.
    ///
    /// The mode [FlexSurfaceMode.highBackgroundLowScaffold] can be used to
    /// replace the style that was produced when using old and removed
    /// `FlexColorScheme.surfaceStyle` enum property `FlexSurface` in
    /// [FlexColorScheme.light] and [FlexColorScheme.dark] before version 4.
    ///
    /// The mode [FlexSurfaceMode.highBackgroundLowScaffold] uses the same
    /// design concept as the only style offered via removed `FlexSurface`
    /// in `FlexColorScheme.surfaceStyle` that was in use before version 4,
    /// and deprecated in version 4.2 and removed in version 5.0.0.
    ///
    /// By adjusting the [FlexColorScheme.blendLevel] property and using this
    /// style, you can find a similar visual effect when using
    /// [FlexSurfaceMode.highBackgroundLowScaffold] with the following values
    /// when matching match most prominent blended [ColorScheme.background]
    /// color.
    ///
    /// In light theme mode:
    ///
    /// * [FlexSurface.material] 0% : blendLevel = 0
    /// * [FlexSurface.light]    2% : blendLevel = 3...4
    /// * [FlexSurface.medium]   4% : blendLevel = 7
    /// * [FlexSurface.strong]   6% : blendLevel = 10
    /// * [FlexSurface.heavy]    8% : blendLevel = 13...14
    ///
    /// In dark theme mode:
    ///
    /// * [FlexSurface.material] 0% : blendLevel = 0
    /// * [FlexSurface.light]    5% : blendLevel = 8
    /// * [FlexSurface.medium]   8% : blendLevel = 13...14
    /// * [FlexSurface.strong]  11% : blendLevel = 19
    /// * [FlexSurface.heavy]   14% : blendLevel = 23
    ///
    /// Since there it is not the same relationship between background and
    /// surface, when using the older [FlexSurface] based style, that uses
    /// individually tuned relationships. The old and new designs do never
    /// align exactly at any blendLevel. The above values produce visually
    /// similar results for the most prominent background color blend.
    ///
    /// To get elevation overlay color in dark themes on all surfaces used by
    /// [Material], use one of the modes where background and dialog color
    /// equals the blend strength on surface color, like [level],
    /// [levelSurfacesLowScaffold], [highScaffoldLowSurfaces] and
    /// [highScaffoldLowSurfaces]. Other modes will only use
    /// elevation overlay if their background happens to be equal to resulting
    /// colorScheme.surface color. For more information
    /// see issue: https://github.com/flutter/flutter/issues/90353
    ///
    /// When using very strong surface branding in dark mode, having an overlay
    /// elevation color in dark mode is less critical, since the elevation
    /// becomes partially visible via shadows and the surface may even have
    /// another color tint if using e.g. [levelSurfacesLowScaffoldVariantDialog]
    /// or [highScaffoldLowSurfacesVariantDialog].
    ///
    /// If values for the properties [surface], [background],
    /// [dialogBackground] or [scaffoldBackground] are given,
    /// they are used instead of values that would be assigned based
    /// on used [FlexSurfaceMode] via [surfaceMode] or [FlexSurface] in
    /// this [surfaceMode].
    ///
    /// Defaults to using [FlexSurfaceMode.highScaffoldLowSurfaces] when
    /// [blendLevel] > 0.
    final FlexSurfaceMode? surfaceMode,

    /// Sets the blend level strength used by the surface mode.
    ///
    /// The blend level is the integer decimal value of the alpha value
    /// used in the alpha blend function. It mixes one color with another
    /// by using alpha opacity value in the color of a surface put on top of
    /// another surface with opaque color and returns the result as one opaque
    /// color.
    ///
    /// Defaults to 0.
    final int blendLevel = 0,

    /// Style used to define the themed color of the AppBar background color.
    ///
    /// Defaults to [FlexAppBarStyle.primary] which produces the same results
    /// as a Flutter standard light [ThemeData.from] by tying the app bar color
    /// to the primary color.
    final FlexAppBarStyle appBarStyle = FlexAppBarStyle.primary,

    /// Themed [AppBar] opacity.
    ///
    /// The opacity is applied to the effective AppBar color, which may be from
    /// used [appBarStyle], that gets its color selection from used [scheme]
    /// or [colors]. Or that color may have been overridden by AppBar sub-theme
    /// and there selected [SchemeColor] based color.
    /// Lastly and with highest priority it may be from here directly supplied
    /// [appBarBackground] color.
    ///
    /// A useful opacity range is from 0.85 to 0.95 when using the [Scaffold]
    /// property [extendBodyBehindAppBar] set to true, to partially show
    /// scrolling content behind the app bar. To use more opacity, in a way
    /// that the AppBar does not become too transparent, you also need to blur
    /// the background to create a frosted glass effect. This cannot
    /// be made with only theming, you need a custom AppBar Widget for that.
    /// Frosted glass UI effect is thus beyond the scope of what
    /// FlexColorScheme can do alone as it only affects ThemeData.
    ///
    /// Defaults to 1, fully opaque, no transparency. Must be from 0 to 1.
    final double appBarOpacity = 1,

    /// When set to `true`, it makes the status bar on Android the same color as
    /// the rest of the AppBar.
    ///
    /// Defaults to true.
    ///
    /// When true, the AppBar in Android mimics the look of one-toned AppBar's
    /// typically used on iOS. Set to `false`, to revert back and use
    /// Android's default two-toned look. If true the status bar area is
    /// actually also transparent so that if the app bar is also translucent,
    /// content that scrolls behind it, is also visible behind the status
    /// bar area.
    final bool transparentStatusBar = true,

    /// The themed elevation for the app bar.
    ///
    /// Default to 0. The 0 elevation is an iOs style
    /// influenced opinionated choice, but it can easily be adjusted for the
    /// theme with this property.
    final double appBarElevation = 0,

    /// The themed elevation for the bottom app bar.
    ///
    /// If null, defaults to the value given to the `appBarElevation` elevation.
    final double? bottomAppBarElevation,

    /// Select preferred themed style for the [TabBarTheme].
    ///
    /// By default the [TabBarTheme] is made to fit with the style of the
    /// [AppBar], via default value [FlexTabBarStyle.forAppBar].
    ///
    /// When setting this to [FlexTabBarStyle.forBackground], it will default
    /// to a theme that uses the color scheme and fits on background color,
    /// which typically also on works surface and scaffoldBackground color.
    /// This TabBarTheme style is useful if you primarily intended to use the
    /// TabBar in a Scaffold, Dialog, Drawer or Side panel on their background
    /// colors.
    final FlexTabBarStyle tabBarStyle = FlexTabBarStyle.forAppBar,

    /// The color displayed most frequently across your app’s screens and
    /// components.
    ///
    /// When using the factory this is an override color for the color that
    /// would be used based on the corresponding color property defined in
    /// [FlexSchemeColor] [colors] or for this color defined when using a
    /// pre-defined color scheme based on [FlexScheme] [scheme] property, or
    /// if a [colorScheme] was provided it will override the same color in it
    /// as well.
    ///
    /// You can use this property for convenience if you want to override the
    /// color that this scheme color gets via the factory behavior.
    ///
    /// This override color is included and affected by factory
    /// properties [usedColors] and [swapColors] and included in their behavior.
    ///
    /// Defaults to null.
    final Color? primary,

    /// A color used for elements needing less emphasis than [primary].
    ///
    /// When using the factory this is an override color for the color that
    /// would be used based on the corresponding color property defined in
    /// [FlexSchemeColor] [colors] or for this color defined when using a
    /// pre-defined color scheme based on [FlexScheme] [scheme] property, or
    /// if a [colorScheme] was provided it will override the same color in it
    /// as well.
    ///
    /// You can use this property for convenience if you want to override the
    /// color that this scheme color gets via the factory behavior.
    ///
    /// The override color is included and affected by factory
    /// properties [usedColors] and [swapColors] and included in their behavior.
    ///
    /// Defaults to null.
    final Color? primaryContainer,

    /// A darker version of the primary color.
    ///
    /// In Flutter SDK the `primaryVariant` color is only used by [SnackBar]
    /// button color in dark theme mode as a part of predefined widget behavior.
    /// If you provide a custom [SnackBarThemeData] where you define
    /// [SnackBarThemeData.actionTextColor] to [primary] or [secondary], this
    /// color property becomes a good property to use if you need a custom color
    /// for custom widgets accessible via your application's ThemeData, that is
    /// not used as default color by any other built-in widgets. This applies
    /// to Flutter 2.8.1 and earlier versions.
    ///
    /// The property is deprecated in Flutter SDK and was replaced
    /// by a new property called [primaryContainer]. It is deprecated from
    /// master v2.6.0-0.0.pre, and in stable (2.10.0).
    /// See https://github.com/flutter/flutter/issues/89852.
    ///
    /// When using the factory this is an override color for the color that
    /// would be used based on the corresponding color property defined in
    /// [FlexSchemeColor] [colors] or for this color defined when using a
    /// pre-defined color scheme based on [FlexScheme] [scheme] property, or
    /// if a [colorScheme] was provided it will override the same color in it
    /// as well.
    ///
    /// You can use this property for convenience if you want to override the
    /// color that this scheme color gets via the factory behavior.
    ///
    /// The override color is included and affected by factory
    /// properties [usedColors] and [swapColors] and included in their behavior.
    ///
    /// Defaults to null.
    @Deprecated('Replaced with `primaryContainer`, after version 4.2.0, '
        'due to deprecation in Flutter master from 2.10.0')
        final Color? primaryVariant,

    /// An accent color that, when used sparingly, calls attention to parts
    /// of your app.
    ///
    /// When using the factory this is an override color for the color that
    /// would be used based on the corresponding color property defined in
    /// [FlexSchemeColor] [colors] or for this color defined when using a
    /// pre-defined color scheme based on [FlexScheme] [scheme] property, or
    /// if a [colorScheme] was provided it will override the same color in it
    /// as well.
    ///
    /// You can use this property for convenience if you want to override the
    /// color that this scheme color gets via the factory behavior.
    ///
    /// The override color is included and affected by factory properties
    /// [usedColors] and [swapColors] and included in their behavior.
    ///
    /// Defaults to null.
    final Color? secondary,

    /// A color used for elements needing less emphasis than [secondary].
    ///
    /// When using the factory this is an override color for the color that
    /// would be used based on the corresponding color property defined in
    /// [FlexSchemeColor] [colors] or for this color defined when using a
    /// pre-defined color scheme based on [FlexScheme] [scheme] property, or
    /// if a [colorScheme] was provided it will override the same color in it
    /// as well.
    ///
    /// You can use this property for convenience if you want to override the
    /// color that this scheme color gets via the factory behavior.
    ///
    /// The override color is included and affected by factory properties
    /// [usedColors] and [swapColors] and included in their behavior.
    ///
    /// Defaults to null.
    final Color? secondaryContainer,

    /// A darker version of the secondary color.
    ///
    /// In Flutter SDK the `secondaryVariant` color is not used by in any
    /// built-in widgets default themes or predefined widget behavior.
    /// It is an excellent property to use if you need a custom color for
    /// custom widgets accessible via your application's ThemeData, and that is
    /// not used as default color by any built-in widgets. So you are in
    /// Flutter 2.8.1 and earlier version free to set it to whatever color you
    /// need and not affect any built-in widgets theme based colors.
    ///
    /// The property is deprecated in Flutter SDK and was replaced
    /// by a new property called [secondaryContainer]. It is deprecated from
    /// master v2.6.0-0.0.pre, and in stable (2.10.0).
    /// See https://github.com/flutter/flutter/issues/89852.
    ///
    /// When using the factory this is an override color for the color that
    /// would be used based on the corresponding color property defined in
    /// [FlexSchemeColor] [colors] or for this color defined when using a
    /// pre-defined color scheme based on [FlexScheme] [scheme] property, or
    /// if a [colorScheme] was provided it will override the same color in it
    /// as well.
    ///
    /// You can use this property for convenience if you want to override the
    /// color that this scheme color gets via the factory behavior.
    ///
    /// The override color is included and affected by factory properties
    /// [usedColors] and [swapColors] and included in their behavior.
    ///
    /// Defaults to null.
    @Deprecated('Replaced with `secondaryContainer`, after version 4.2.0, '
        'due to deprecation in Flutter master from 2.10.0')
        final Color? secondaryVariant,

    /// A color used as a contrasting accent that can balance [primary]
    /// and [secondary] colors or bring heightened attention to an element,
    /// such as an input field.
    ///
    /// When using the factory this is an override color for the color that
    /// would be used based on the corresponding color property defined in
    /// [FlexSchemeColor] [colors] or for this color defined when using a
    /// pre-defined color scheme based on [FlexScheme] [scheme] property, or
    /// if a [colorScheme] was provided it will override the same color in it
    /// as well.
    ///
    /// You can use this property for convenience if you want to override the
    /// color that this scheme color gets via the factory behavior.
    ///
    /// The override color is included and affected by factory properties
    /// [usedColors] and [swapColors] and included in their behavior.
    ///
    /// Defaults to null.
    final Color? tertiary,

    /// A color used for elements needing less emphasis than [tertiary].
    ///
    /// When using the factory this is an override color for the color that
    /// would be used based on the corresponding color property defined in
    /// [FlexSchemeColor] [colors] or for this color defined when using a
    /// pre-defined color scheme based on [FlexScheme] [scheme] property, or
    /// if a [colorScheme] was provided it will override the same color in it
    /// as well.
    ///
    /// You can use this property for convenience if you want to override the
    /// color that this scheme color gets via the factory behavior.
    ///
    /// The override color is included and affected by factory properties
    /// [usedColors] and [swapColors] and included in their behavior.
    ///
    /// Defaults to null.
    final Color? tertiaryContainer,

    /// The color to use for input validation errors, e.g. for
    /// [InputDecoration.errorText].
    ///
    /// When using the factory this is an override color for the color that
    /// would be used based on the corresponding color property defined in
    /// [FlexSchemeColor] [colors] or for this color defined when using a
    /// pre-defined color scheme based on [FlexScheme] [scheme] property, or
    /// if a [colorScheme] was provided it will override the same color in it
    /// as well.
    ///
    /// You can use this property for convenience if you want to override the
    /// color that this scheme color gets via the factory behavior.
    final Color? error,

    /// The surface (background) color for widgets like [Card] and
    /// [BottomAppBar].
    ///
    /// The color is applied to [ThemeData.cardColor] and
    /// [ColorScheme.surface] in [ThemeData.colorScheme], it is also used
    /// by all [Material] of type [MaterialType.card].
    ///
    /// When using the factory this is an override color for the color that
    /// would be used based on mode defined by property
    /// [surfaceMode] [FlexSurfaceMode] enum or [surfaceStyle] enum
    /// [FlexSurface], or if a [colorScheme] was provided it will override the
    /// same color in it as well.
    ///
    /// Defaults to null.
    final Color? surface,

    /// A color that typically appears behind scrollable content.
    ///
    /// The color is applied to [ThemeData.canvasColor] and
    /// [ThemeData.backgroundColor], it is used eg by menu [Drawer] and by all
    /// [Material] of type [MaterialType.canvas].
    ///
    /// When using the factory this is an override color for the color that
    /// would be used based on mode defined by property
    /// [surfaceMode] [FlexSurfaceMode] enum or [surfaceStyle] enum
    /// [FlexSurface], or if a [colorScheme] was provided it will override the
    /// same color in it as well.
    ///
    /// Defaults to null.
    final Color? background,

    /// The color of the [Scaffold] background.
    ///
    /// The color is applied to [ThemeData.scaffoldBackgroundColor].
    ///
    /// When using the factory this is an override color for the color that
    /// would be used based on mode defined by property
    /// [surfaceMode] [FlexSurfaceMode] enum or [surfaceStyle] enum
    /// [FlexSurface].
    ///
    /// Defaults to null.
    final Color? scaffoldBackground,

    /// The background color of [Dialog] elements.
    ///
    /// The color is applied to [ThemeData.dialogBackgroundColor].
    ///
    /// When using the factory this is an override color for the color that
    /// would be used based on mode defined by property
    /// [surfaceMode] [FlexSurfaceMode] enum or [surfaceStyle] enum
    /// [FlexSurface].
    ///
    /// If you assign a background [SchemeColor] to [dialogBackgroundColor] in
    /// [FlexSubThemesData] and you have opted in on using component sub themes
    /// with [useSubThemes], then its selected scheme color will override this
    /// value.
    ///
    /// Defaults to null.
    final Color? dialogBackground,

    /// Background theme color for the [AppBar].
    ///
    /// When using the factory this is an override color for the color that
    /// would be used based on the corresponding color property defined in
    /// [FlexSchemeColor] [colors] or for this color defined when using a
    /// pre-defined color scheme based on [FlexScheme] `scheme` property and
    /// the [FlexAppBarStyle] [appBarStyle] property.
    ///
    /// Thus custom color will also override any scheme color based selection
    /// for the [AppBAr] in active used sub-themes.
    final Color? appBarBackground,

    /// A color that is clearly legible when drawn on [primary] color.
    ///
    /// To ensure that an app is accessible, a contrast ratio of 4.5:1 for
    /// [primary] and [onPrimary] is recommended. See
    /// <https://www.w3.org/TR/UNDERSTANDING-WCAG20/visual-audio-contrast-contrast.html>.
    ///
    /// When using this factory, this is an override color for the color that
    /// would be used based on the corresponding color property defined in
    /// [FlexSchemeColor] [colors] property or when using pre-defined color
    /// scheme based [FlexScheme] and its [scheme] property, including any
    /// used blend logic. If a [colorScheme] was provided with this
    /// corresponding color defined, this color property will override the
    /// same color in it as well.
    ///
    /// You can use this property for convenience if you want to override the
    /// color that this scheme color gets via the factory behavior.
    final Color? onPrimary,

    /// A color that's clearly legible when drawn on `primaryVariant`.
    ///
    /// To ensure that an app is accessible, a contrast ratio between
    /// `primaryVariant` and [onPrimaryContainer] of at least 4.5:1
    /// is recommended. See
    /// <https://www.w3.org/TR/UNDERSTANDING-WCAG20/visual-audio-contrast-contrast.html>.
    ///
    /// When using this factory, this is an override color for the color that
    /// would be used based on the corresponding color property defined in
    /// [FlexSchemeColor] [colors] property or when using pre-defined color
    /// scheme based [FlexScheme] and its [scheme] property, including any
    /// used blend logic. If a [colorScheme] was provided with this
    /// corresponding color defined, this color property will override the
    /// same color in it as well.
    ///
    /// You can use this property for convenience if you want to override the
    /// color that this scheme color gets via the factory behavior.
    final Color? onPrimaryContainer,

    /// A color that is clearly legible when drawn on [secondary] color.
    ///
    /// To ensure that an app is accessible, a contrast ratio of 4.5:1 for
    /// [secondary] and [onSecondary] is recommended. See
    /// <https://www.w3.org/TR/UNDERSTANDING-WCAG20/visual-audio-contrast-contrast.html>.
    ///
    /// When using this factory, this is an override color for the color that
    /// would be used based on the corresponding color property defined in
    /// [FlexSchemeColor] [colors] property or when using pre-defined color
    /// scheme based [FlexScheme] and its [scheme] property, including any
    /// used blend logic. If a [colorScheme] was provided with this
    /// corresponding color defined, this color property will override the
    /// same color in it as well.
    ///
    /// You can use this property for convenience if you want to override the
    /// color that this scheme color gets via the factory behavior.
    final Color? onSecondary,

    /// A color that's clearly legible when drawn on [secondaryContainer].
    ///
    /// To ensure that an app is accessible, a contrast ratio between
    /// [secondaryContainer] and [onSecondaryContainer] of at least 4.5:1
    /// is recommended. See
    /// <https://www.w3.org/TR/UNDERSTANDING-WCAG20/visual-audio-contrast-contrast.html>.
    ///
    /// When using this factory, this is an override color for the color that
    /// would be used based on the corresponding color property defined in
    /// [FlexSchemeColor] [colors] property or when using pre-defined color
    /// scheme based [FlexScheme] and its [scheme] property, including any
    /// used blend logic. If a [colorScheme] was provided with this
    /// corresponding color defined, this color property will override the
    /// same color in it as well.
    ///
    /// You can use this property for convenience if you want to override the
    /// color that this scheme color gets via the factory behavior.
    final Color? onSecondaryContainer,

    /// A color that's clearly legible when drawn on [tertiary].
    ///
    /// To ensure that an app is accessible, a contrast ratio of 4.5:1 for
    /// [secondary] and [onSecondary] is recommended. See
    /// <https://www.w3.org/TR/UNDERSTANDING-WCAG20/visual-audio-contrast-contrast.html>.
    ///
    /// When using this factory, this is an override color for the color that
    /// would be used based on the corresponding color property defined in
    /// [FlexSchemeColor] [colors] property or when using pre-defined color
    /// scheme based [FlexScheme] and its [scheme] property, including any
    /// used blend logic. If a [colorScheme] was provided with this
    /// corresponding color defined, this color property will override the
    /// same color in it as well.
    ///
    /// You can use this property for convenience if you want to override the
    /// color that this scheme color gets via the factory behavior.
    final Color? onTertiary,

    /// A color that's clearly legible when drawn on [tertiaryContainer].
    ///
    /// To ensure that an app is accessible, a contrast ratio between
    /// [secondaryContainer] and [onSecondaryContainer] of at least 4.5:1
    /// is recommended. See
    /// <https://www.w3.org/TR/UNDERSTANDING-WCAG20/visual-audio-contrast-contrast.html>.
    ///
    /// When using this factory, this is an override color for the color that
    /// would be used based on the corresponding color property defined in
    /// [FlexSchemeColor] [colors] property or when using pre-defined color
    /// scheme based [FlexScheme] and its [scheme] property, including any
    /// used blend logic. If a [colorScheme] was provided with this
    /// corresponding color defined, this color property will override the
    /// same color in it as well.
    ///
    /// You can use this property for convenience if you want to override the
    /// color that this scheme color gets via the factory behavior.
    final Color? onTertiaryContainer,

    /// A color that is clearly legible when drawn on [surface] color.
    ///
    /// To ensure that an app is accessible, a contrast ratio of 4.5:1 for
    /// [surface] and [onSurface] is recommended. See
    /// <https://www.w3.org/TR/UNDERSTANDING-WCAG20/visual-audio-contrast-contrast.html>.
    ///
    /// When using this factory, this is an override color for the color that
    /// would be used based on the corresponding color property defined in
    /// [FlexSchemeColor] [colors] property or when using pre-defined color
    /// scheme based [FlexScheme] and its [scheme] property, including any
    /// used blend logic. If a [colorScheme] was provided with this
    /// corresponding color defined, this color property will override the
    /// same color in it as well.
    ///
    /// You can use this property for convenience if you want to override the
    /// color that this scheme color gets via the factory behavior.
    final Color? onSurface,

    /// A color that is clearly legible when drawn on [background] color.
    ///
    /// To ensure that an app is accessible, a contrast ratio of 4.5:1 for
    /// [background] and [onBackground] is recommended. See
    /// <https://www.w3.org/TR/UNDERSTANDING-WCAG20/visual-audio-contrast-contrast.html>.
    ///
    /// When using this factory, this is an override color for the color that
    /// would be used based on the corresponding color property defined in
    /// [FlexSchemeColor] [colors] property or when using pre-defined color
    /// scheme based [FlexScheme] and its [scheme] property, including any
    /// used blend logic. If a [colorScheme] was provided with this
    /// corresponding color defined, this color property will override the
    /// same color in it as well.
    ///
    /// You can use this property for convenience if you want to override the
    /// color that this scheme color gets via the factory behavior.
    final Color? onBackground,

    /// A color that is clearly legible when drawn on [error] color.
    ///
    /// To ensure that an app is accessible, a contrast ratio of 4.5:1 for
    /// [error] and [onError] is recommended. See
    /// <https://www.w3.org/TR/UNDERSTANDING-WCAG20/visual-audio-contrast-contrast.html>.
    ///
    /// When using this factory, this is an override color for the color that
    /// would be used based on the corresponding color property defined in
    /// [FlexSchemeColor] [colors] property or when using pre-defined color
    /// scheme based [FlexScheme] and its [scheme] property, including any
    /// used blend logic. If a [colorScheme] was provided with this
    /// corresponding color defined, this color property will override the
    /// same color in it as well.
    ///
    /// You can use this property for convenience if you want to override the
    /// color that this scheme color gets via the factory behavior.
    final Color? onError,

    /// A color used as an overlay on a surface color to indicate a component's
    /// elevation.
    ///
    /// You can use this property for convenience if you want to override the
    /// color that this scheme color gets via the factory behavior.
    /// If a [colorScheme] was provided where this corresponding color is
    /// defined, this color property will override the same color in it.
    ///
    /// This color is used by M3 for colored elevation, it is also used as the
    /// blend color for FlexColorScheme surface blends.
    ///
    /// If undefined it defaults to [primary] color.
    final Color? surfaceTint,

    /// Makes the light theme backgrounds lighter or even white.
    ///
    /// Scaffold background will become white, and other surfaces also get
    /// lighter (8%), if using low blend levels they may become fully white too.
    final bool lightIsWhite = false,

    /// When true, the primary and primaryVariant colors will be swapped with
    /// their secondary counter parts.
    ///
    /// Set this flag to true if you want to make a theme where
    /// your primary and secondary colors are swapped, compared to how they
    /// are defined in the passed in color properties or used pre-defined
    /// color scheme.
    ///
    /// This is useful if you want to do this with the pre-defined
    /// schemes. If you are explicitly defining all your theme colors you can
    /// of course define them in any desired config. Even if you do
    /// that, this feature will still swap whatever colors you defined
    /// for primary and secondary. You can offer this feature as an easy end
    /// user modifiable theme option if you like. One usage possibility is to
    /// set `swapColors` to true only for the dark modem and use your color
    /// scheme the other way around only in dark mode.
    final bool swapColors = false,

    /// When `true`, tooltip background color will match the brightness of the
    /// theme's background color.
    ///
    /// By default Flutter's Material tooltips use a theme where the tooltip
    /// background color brightness is inverted in relation to the overall
    /// theme's background color.
    ///
    /// FlexColorScheme allows you to use a single
    /// toggle to invert this. Light tooltips on light background is e.g. the
    /// default style on Windows Desktop. You can use this toggle to use this
    /// style, or as a means to create a platform adaptive
    /// tooltip style, where the Material/Flutter style is used on devices and
    /// Web, but the inverted scheme is used on desktop platforms.
    ///
    /// Defaults to false, and uses same background style as Material Design
    /// guide and Flutter.
    ///
    /// Regardless of value used on this property, the tooltip theme created by
    /// [FlexColorScheme] does however deviate a bit from the Flutter default
    /// theme, it has slightly larger font for improved legibility on web and
    /// desktop with device pixel ratio 1.0 and also use a padding style also
    /// suitable for multiline tooltips.
    final bool tooltipsMatchBackground = false,

    /// This property has no function after 4.2.0. Prior to version 5 this
    /// property was used to activate the opinionated component sub-themes.
    /// Starting with version 5 they are now enabled by adding a default
    /// constructor `FlexSubThemesData()` to [subThemesData].
    ///
    /// Defaults to false.
    @Deprecated('This property has no function after 4.2.0. FlexColorScheme '
        'opinionated component sub-themes are added by adding a default '
        'constructor FlexSubThemesData() to subThemesData. This creates '
        'sub-themes using the FlexColorScheme opinionated defaults. You can '
        'modify the sub-themes by changing the FlexSubThemesData properties.')
        final bool useSubThemes = false,

    /// Activate using FlexColorScheme opinionated component sub-themes by
    /// passing in a default `FlexSubThemesData()`.
    ///
    /// To further configure the sub-themes, change the simple flat value
    /// properties as desired in `FlexSubThemesData()`.
    ///
    /// By default [FlexThemeData.light], [FlexThemeData.dark] and
    /// [FlexColorScheme.toTheme], do as little as they need to just
    /// provide a consistent Material 2 color schemed theme. The additions they
    /// do are described in [FlexColorScheme.toTheme].
    ///
    /// The original purpose of the opinionated sub-themes was to make it easy
    /// to add themed corner radius to all Widgets that support it, and to
    /// provide a consistent look on all buttons, including [ToggleButtons].
    ///
    /// Therefore the sub themes are a convenient way to opt-in on customized
    /// corner radius on Widgets using above themes. By opting in you can set
    /// corner radius for all covered Widgets to same corner radius in one go.
    /// There are also properties to override the global default for each widget
    /// to set different rounding per widget if so desired.
    ///
    /// By default, if a `defaultRadius` is not specified, each widgets corner
    /// radius and some other styling take inspiration from the Material 3 (M3)
    /// specification https://m3.material.io/ and uses its specifications as
    /// defaults when it is possible to do so in Flutter SDK theming, within
    /// its current Material 2 (M2) design limitations.
    ///
    /// In version 5, by opting in via a default [subThemesData] you
    /// get an extensive set of widget component sub themes applied.
    /// They can be customized via the [subThemesData] property, that has
    /// quick and flat sub theme configuration values in the data class
    /// [FlexSubThemesData].
    ///
    /// These component themes are available:
    ///
    /// * [ButtonThemeData] for old deprecated buttons, via [buttonTheme].
    /// * [BottomNavigationBarThemeData] for [BottomNavigationBar] via
    ///   [bottomNavigationBar].
    /// * [BottomSheetThemeData] for [BottomSheet] via [bottomSheetTheme].
    /// * [CardTheme] for [Card] via [cardTheme].
    /// * [CheckboxThemeData] for [Checkbox] via [checkboxTheme].
    /// * [ChipThemeData] for [Chip] via [chipTheme].
    /// * [DialogTheme] for [Dialog] via [dialogTheme].
    /// * [ElevatedButtonThemeData] for [ElevatedButton] via
    ///   [elevatedButtonTheme].
    /// * [FloatingActionButtonThemeData] for [FloatingActionButton] via
    ///   [floatingActionButtonTheme].
    /// * [InputDecorationTheme] for [InputDecoration] via
    ///   [inputDecorationTheme].
    /// * [NavigationBarThemeData] for [NavigationBar] via [navigationBarTheme].
    /// * [NavigationRailThemeData] for [NavigationRail] via
    ///   [navigationRailTheme].
    /// * [OutlinedButtonThemeData] for [OutlinedButton] via
    ///   [outlinedButtonTheme].
    /// * [PopupMenuThemeData] for [PopupMenuButton] via [popupMenuTheme].
    /// * [RadioThemeData] for [Radio] via [radioTheme].
    /// * [SnackBarThemeData] for [SnackBar] via [snackBarTheme].
    /// * [SwitchThemeData] for [Switch] via [switchTheme].
    /// * [TextButtonThemeData] for [TextButton] via [textButtonTheme].
    /// * [TimePickerThemeData] for [TimePickerDialog] via [timePickerTheme].
    /// * [ToggleButtonsThemeData] for [ToggleButtons] via [toggleButtonsTheme].
    ///
    /// The custom [ButtonThemeData] still provides matching styling
    /// for the deprecated legacy buttons if they are used.
    /// Please consider phasing out the legacy buttons, as they are deprecated
    /// and will be removed from the Flutter SDK in next stable release. Their
    /// theme [ButtonThemeData] will also soon be deprecated and later removed.
    ///
    /// Defaults to null, resulting in FlexColorScheme not using any extra
    /// sub-theming in addition to those described in [FlexColorScheme.toTheme].
    final FlexSubThemesData? subThemesData,

    /// To use and activate Material 3 color system based [ColorScheme]
    /// defined via key colors for primary, secondary and tertiary colors and
    /// the [TonalPalette] generated by these key color values, pass
    /// in a [FlexKeyColors] to [keyColors].
    ///
    /// By default it is not defined (null), and a traditional manually
    /// configured color scheme will be created based on input property values
    /// or the passed in [colorScheme].
    ///
    /// If a [FlexKeyColors] instance is passed in, the key color seeding
    /// behavior depends on properties defined in the [FlexKeyColors]
    /// instance. The default constructor makes one where
    /// [FlexKyColors.useKeyColors] is true, it will automatically enable usage
    /// of key colors and from them generated color scheme.
    ///
    /// For more information on Material 3 color system and usage of key colors
    /// to generate tonal palettes and tones, see:
    /// https://m3.material.io/styles/color/the-color-system/key-colors-tones
    final FlexKeyColors? keyColors,

    /// Set to true, to use the new Material 3 error colors.
    ///
    /// If [useMaterial3ErrorColors] is false, the generated [ColorScheme]
    /// and [ThemeData] will use Material 2 default error colors or
    /// error colors as defined by the built in color schemes. Thus using same
    /// error colors as in FlexColorScheme versions before version 5.
    ///
    /// If [useMaterial3ErrorColors] is true, the resulting [ColorScheme]
    /// and [ThemeData] will use the Material 3 design guide error colors.
    ///
    /// Key color seed generated [ColorScheme]s always use the Material 3
    /// design guide error colors, or error colors from its customized
    /// [TonalPalette] generation setup.
    final bool useMaterial3ErrorColors = false,

    /// An advanced configuration class enabling complete customization of
    /// used chroma for [TonalPalette] generation for the used seed [keyColors],
    /// as well as changing which tone in the tonal palettes is used
    /// for which [ColorScheme] color.
    ///
    /// If null [FlexTones.light] will be used, resulting in a default
    /// Material Design 3 based usage of tones and CAM16 chroma for the
    /// seed generated light [ColorScheme].
    final FlexTones? tones,

    /// The density value for specifying the compactness of various UI
    /// components.
    ///
    /// Consider using [FlexColorScheme.comfortablePlatformDensity],
    /// it is similar to [VisualDensity.adaptivePlatformDensity], but the
    /// density for desktop and Web is less dense in order to offer a bit larger
    /// touch friendly surfaces, but not quite as large as small touch devices.
    ///
    /// This is the same property as in [ThemeData] factory, it is just
    /// passed along to it. Included for convenience to avoid a copyWith if
    /// to change it.
    ///
    /// Density, in the context of a UI, is the vertical and horizontal
    /// "compactness" of the elements in the UI. It is unit less, since it means
    /// different things to different UI elements. For buttons, it affects the
    /// spacing around the centered label of the button. For lists, it affects
    /// the distance between baselines of entries in the list.
    ///
    /// Typically, density values are integral, but any value in range may be
    /// used. The range includes values from [VisualDensity.minimumDensity]
    /// (which is -4), to [VisualDensity.maximumDensity] (which is 4),
    /// inclusive, where negative values indicate a denser, more compact, UI,
    /// and positive values indicate a less dense, more expanded, UI. If a
    /// component doesn't support the value given, it will clamp to the nearest
    /// supported value.
    ///
    /// The default for visual densities is zero for both vertical and
    /// horizontal densities, which corresponds to the default visual density of
    /// components in the Material Design specification.
    ///
    /// As a rule of thumb, a change of 1 or -1 in density corresponds to 4
    /// logical pixels. However, this is not a strict relationship since
    /// components interpret the density values appropriately for their needs.
    ///
    /// A larger value translates to a spacing increase (less dense), and a
    /// smaller value translates to a spacing decrease (more dense).
    ///
    /// Defaults to [VisualDensity.adaptivePlatformDensity].
    final VisualDensity? visualDensity,

    /// Text with a color that contrasts with the card and canvas colors.
    final TextTheme? textTheme,

    /// A text theme that contrasts with the primary color.
    final TextTheme? primaryTextTheme,

    /// Same property as in [ThemeData] factory, it is just passed along to it.
    ///
    /// Included for convenience to avoid a copyWith if it needs to be changed.
    final String? fontFamily,

    /// The platform adaptive widgets should adapt to target and mechanics too.
    ///
    /// Same property as in [ThemeData] factory. Included for convenience to
    /// avoid a copyWith change it.
    ///
    /// Defaults to the current platform, as exposed by [defaultTargetPlatform].
    /// This should be used in order to style UI elements according to platform
    /// conventions.
    ///
    /// Widgets from the material library should use this getter (via
    /// [Theme.of]) to determine the current platform for the purpose of
    /// emulating the platform behavior (e.g. scrolling or haptic effects).
    /// Widgets and render objects at lower layers that try to emulate the
    /// underlying platform platform can depend on [defaultTargetPlatform]
    /// directly, or may require that the target platform be provided as an
    /// argument. The `dart.io.Platform` object should only be used directly
    /// when it's critical to actually know the current platform, without
    /// any overrides possible, e.g. when a system API is about to be called.
    ///
    /// In a test environment, the platform returned is [TargetPlatform.android]
    /// regardless of the host platform. (Android was chosen because the tests
    /// were originally written assuming Android-like behavior, and we added
    /// platform adaptations for other platforms later). Tests can check
    /// behavior for other platforms by setting the [platform] of the [Theme]
    /// explicitly to another [TargetPlatform] value, or by setting
    /// [debugDefaultTargetPlatformOverride].
    final TargetPlatform? platform,

    /// The color and geometry [TextTheme] values use to configure [textTheme].
    ///
    /// Same property as in [ThemeData] factory. Included for convenience to
    /// avoid a copyWith change it.
    ///
    /// Included for convenience to avoid a copyWith if it needs to be changed.
    /// Default value deviates from the Flutter standard that uses the old
    /// [Typography.material2014], in favor of newer [Typography.material2018]
    /// as default typography if one is not provided.
    ///
    /// Never mix different [Typography] in light and dark theme mode. If you
    /// do, lerp between dark and light theme mode will fail due Flutter SDK
    /// not being able to handle the use case. See issue:
    /// https://github.com/flutter/flutter/issues/89947
    ///
    /// If you use a default light or
    /// dark Flutter ThemeData() and a FlexColorScheme.toTheme() ThemeData for
    /// the other mode, you must set either the default ThemeData to
    /// [Typography.material2018] OR the [FlexColorScheme.typography] to
    /// [Typography.material2014] to avoid this issue. It is not generally
    /// recommended to create your light and dark theme data with
    /// different methods. If you use FlexColorScheme, DO use it for both the
    /// light and dark theme mode.
    final Typography? typography,

    /// Apply a semi-transparent overlay color on Material surfaces to indicate
    /// elevation for dark themes.
    ///
    /// Same property as in [ThemeData] factory. Included for convenience to
    /// avoid a copyWith change it.
    ///
    /// In FlexColorScheme it defaults to true. In Flutter [ThemeData.from] it
    /// also default to true, but in [ThemeData] factory it defaults to false.
    ///
    /// Material drop shadows can be difficult to see in a dark theme, so the
    /// elevation of a surface should be portrayed with an "overlay" in addition
    /// to the shadow. As the elevation of the component increases, the
    /// overlay increases in opacity. The [applyElevationOverlayColor] turns the
    /// application of this overlay on or off for dark themes.
    ///
    /// If true and [brightness] is [Brightness.dark], a
    /// semi-transparent version of [ColorScheme.onSurface] will be
    /// applied on top of [Material] widgets that have a [ColorScheme.surface]
    /// color. The level of transparency is based on [Material.elevation] as
    /// per the Material Dark theme specification.
    ///
    /// If false the surface color will be used unmodified.
    ///
    /// Defaults to false in order to maintain backwards compatibility with
    /// apps that were built before the Material Dark theme specification
    /// was published. New apps should set this to true for any themes
    /// where [brightness] is [Brightness.dark].
    ///
    /// See also:
    ///
    ///  * [Material.elevation], which effects the level of transparency of the
    ///    overlay color.
    ///  * [ElevationOverlay.applyOverlay], which is used by [Material] to apply
    ///    the overlay color to its surface color.
    ///  * <https://material.io/design/color/dark-theme.html>, which specifies
    ///    how the overlay should be applied.
    ///
    /// Known limitations:
    ///
    /// Because of how the overlay color application is implemented in Flutter
    /// SDK, you will only get overlay color applied in dark mode when this
    /// value  is true, if the [Material] surface color being elevated is equal
    /// to [ThemeData.colorScheme] and its [ColorScheme.surface] color property.
    ///
    /// Thus when using color branded surfaces, if you want all [Material]
    /// surfaces in your theme to get an overlay color in dark mode, you must
    /// for dark themes only use background colors that are equal to the surface
    /// color. This when using [FlexColorScheme.dark] use a [FlexSurfaceMode]
    /// that starts with `equal`. That said, if using heavy color branding,
    /// some surfaces may not need any overlay color, so the
    /// lack of it might not be an issue with other modes in such themes.
    /// For more information about this limitation see Flutter SDK issue:
    /// https://github.com/flutter/flutter/issues/90353
    final bool applyElevationOverlayColor = true,

    /// A temporary flag used to opt-in to new SDK Material 3 features.
    ///
    /// Flutter SDK 3.0.5 [useMaterial3] documentation:
    /// -----------------------------------------------
    /// If true, then components that have been migrated to Material 3 will
    /// use new colors, typography and other features of Material 3.
    /// If false, they will use the Material 2 look and feel.
    ///
    /// If a [ThemeData] is constructed with [useMaterial3] set to true, then
    /// some properties will get special defaults. However, just copying a
    /// [ThemeData] with [useMaterial3] set to true will not change any of
    /// these properties in the
    /// resulting [ThemeData]. These properties are:
    /// <style>table,td,th { border-collapse: collapse; padding: 0.45em; }
    /// td { border: 1px solid }</style>
    ///
    /// | Property        | Material 3 default           | Fallback default  |
    /// | :-------------- | :--------------------------- | :---------------- |
    /// | [typography] | [Typography.material2021] | [Typography.material2014] |
    /// | [splashFactory] | [InkSparkle]* or [InkRipple] | [InkSplash]       |
    ///
    /// \* if and only if the target platform is Android and the app is not
    /// running on the web, otherwise it will fallback to [InkRipple].
    ///
    /// During the migration to Material 3, turning this on may yield
    /// inconsistent look and feel in your app. Some components will be migrated
    /// before others and typography changes will be coming in stages.
    ///
    /// [useMaterial3] defaults to false. After all the migrated components
    /// have landed on stable, we will change this to be true by default. After
    /// that change has landed on stable, we will deprecate this flag and remove
    /// all uses of it. Everything will use the Material 3 look and feel at
    /// that point.
    ///
    /// Components that have been migrated to Material 3 are:
    ///
    ///   * [AlertDialog]
    ///   * [AppBar]
    ///   * [Card]
    ///   * [Dialog]
    ///   * [ElevatedButton]
    ///   * [FloatingActionButton]
    ///   * [Material]
    ///   * [NavigationBar]
    ///   * [NavigationRail]
    ///   * [OutlinedButton]
    ///   * [StretchingOverscrollIndicator], replacing the
    ///     [GlowingOverscrollIndicator]
    ///   * [TextButton]
    ///
    /// See also:
    ///
    ///   * [Material Design 3](https://m3.material.io).
    ///
    /// While the migration of Flutter SDK to the Material 3 design spec is
    /// in progress, setting [useSubThemes] in [FlexColorScheme] to true,
    /// will also produce widget sub-themes using current Flutter Material 2
    /// theming limitations. By default these opinionated sub-themes also
    /// implement the Material 3 design and look when it is possible within
    /// current SDK limits. During SDK transition to full M3 support, keeping
    /// useMaterial3 false and just using the FlexColorScheme sub-theming, may
    /// be preferred since it has fewer transitional issues.
    final bool useMaterial3 = false,

    /// Arbitrary additions to this theme.
    ///
    /// This is the same property as [extensions] in ThemeData, it is provided
    /// as a convenience pass-through to ThemeData.
    ///
    /// To define extensions, pass an [Iterable] containing one or more
    /// [ThemeExtension] subclasses to [ThemeData.new] or [copyWith].
    ///
    /// To obtain an extension, use ThemeData.of(context).extension.
    final Iterable<ThemeExtension<dynamic>>? extensions,
  }) {
    // LIGHT: Check valid inputs
    assert(usedColors >= 1 && usedColors <= 6, 'usedColors must be 1 to 6');
    assert(appBarOpacity >= 0 && appBarOpacity <= 1,
        'appBarOpacity must be 0 to 1');
    assert(
      blendLevel >= 0 && blendLevel <= 40,
      'Only blend levels from 0 to 40 are allowed. Very high alpha values may '
      'not produce results that are visually very appealing or useful.',
    );
    assert(appBarElevation >= 0.0, 'AppBar elevation must be >= 0.');
    assert(bottomAppBarElevation == null || bottomAppBarElevation >= 0.0,
        'Bottom AppBar elevation must be null or must be >= 0.');
    // If bottomAppBarElevation was null, fallback to appBarElevation.
    final double effectiveBottomAppBarElevation =
        bottomAppBarElevation ?? appBarElevation;
    // Use color seeding based on passed in keyColors or make one where
    // it is not used, if one was not defined, since we want that as default
    // behavior to match past default behavior.
    final FlexKeyColors seed =
        keyColors ?? const FlexKeyColors(useKeyColors: false);
    // Fallback value for scheme is default material scheme.
    final FlexScheme flexScheme = scheme ?? FlexScheme.material;
    // If colors was null, we used the scheme based value.
    final FlexSchemeColor flexColors =
        colors ?? FlexColor.schemes[flexScheme]!.light;

    // If the passed in property values are not null, or there was a colorScheme
    // provided, we will override the colors properties with them. Doing it here
    // gets also correct effective and swap behavior on directly passed in
    // property values or colorScheme based colors too.
    final FlexSchemeColor withPassedColors = flexColors.copyWith(
      primary: primary ?? colorScheme?.primary,
      // Use primaryVariant also as potential passed in override for
      // container, for backwards behavior compatibility.
      // TODO(rydmike): Remove backwards compatibility behavior in v6.0.0.
      primaryContainer:
          primaryContainer ?? primaryVariant ?? colorScheme?.primaryContainer,
      secondary: secondary ?? colorScheme?.secondary,
      // Use old secondaryVariant also as potential passed in override for
      // container, for backwards behavior compatibility.
      secondaryContainer: secondaryContainer ??
          secondaryVariant ??
          colorScheme?.secondaryContainer,
      tertiary: tertiary ?? colorScheme?.tertiary,
      tertiaryContainer: tertiaryContainer ?? colorScheme?.tertiaryContainer,
      error: error ?? colorScheme?.error,
      errorContainer: colorScheme?.errorContainer,
    );
    // First cut of effective FlexSchemeColor depends on colors, usedColors
    // and swap. When we use Brightness.light, we also guarantee that we have
    // colors on effectiveColors.error and errorContainer, they are guaranteed
    // to no longer be null after this call.
    FlexSchemeColor effectiveColors = FlexSchemeColor.effective(
      withPassedColors,
      usedColors,
      swapColors: swapColors,
      brightness: Brightness.light,
    );
    // ColorScheme to hold our seeded scheme colors, it will be kept as null
    // if we do not use M3 key based seeded tonal palette ColorScheme.
    ColorScheme? seedScheme;
    // If keyColor seeds is active, apply seeded colors to effective colors.
    if (seed.useKeyColors) {
      // Create a complete ColorScheme from active and effective seed colors.
      seedScheme = _Scheme.fromSeeds(
        brightness: Brightness.light,
        primaryKey: effectiveColors.primary,
        // If use secondary seed, use it with fromSeeds, otherwise undefined.
        secondaryKey: seed.useSecondary ? effectiveColors.secondary : null,
        // If use tertiary seed, use it with fromSeeds, otherwise undefined.
        tertiaryKey: seed.useTertiary ? effectiveColors.tertiary : null,
        // Use provided tones configuration or default one.
        tones: tones ?? const FlexTones.light(),
        surfaceTint: surfaceTint,
      );
      // Update effective main colors to seed colors, keeping configured
      // effective main color values when so defined.
      effectiveColors = FlexSchemeColor(
        primary:
            seed.keepPrimary ? effectiveColors.primary : seedScheme.primary,
        primaryContainer: seed.keepPrimaryContainer
            ? effectiveColors.primaryContainer
            : seedScheme.primaryContainer,
        secondary: seed.keepSecondary
            ? effectiveColors.secondary
            : seedScheme.secondary,
        secondaryContainer: seed.keepSecondaryContainer
            ? effectiveColors.secondaryContainer
            : seedScheme.secondaryContainer,
        tertiary:
            seed.keepTertiary ? effectiveColors.tertiary : seedScheme.tertiary,
        tertiaryContainer: seed.keepTertiaryContainer
            ? effectiveColors.tertiaryContainer
            : seedScheme.tertiaryContainer,
        appBarColor: effectiveColors.appBarColor,
        error: seedScheme.error,
        errorContainer: seedScheme.errorContainer,
      );
    }
    // Get effective surfaceTint color, also used as blend color for surfaces.
    final Color blendColor =
        surfaceTint ?? colorScheme?.surfaceTint ?? effectiveColors.primary;
    // Compute surface blends, they are also be added to seeded surfaces.
    final FlexSchemeSurfaceColors surfaceSchemeColors =
        FlexSchemeSurfaceColors.blend(
      brightness: Brightness.light,
      surfaceMode: surfaceMode ?? FlexSurfaceMode.highScaffoldLowSurfaces,
      blendLevel: blendLevel,
      surfaceVariantBlendDivide: seed.useKeyColors ? 2 : 1,
      schemeColors: effectiveColors,
      blendColors: FlexSchemeSurfaceColors(
        surface: blendColor,
        surfaceVariant: blendColor,
        inverseSurface: blendColor,
        dialogBackground: blendColor,
        background: blendColor,
        scaffoldBackground: blendColor,
      ),
      surfaceColors: seed.useKeyColors
          // Using seed colors, starting surfaces are given by generated scheme.
          ? FlexSchemeSurfaceColors(
              surface: seedScheme!.surface,
              surfaceVariant: seedScheme.surfaceVariant,
              inverseSurface: seedScheme.inverseSurface,
              dialogBackground: seedScheme.surface,
              background: seedScheme.background,
              scaffoldBackground: seedScheme.background,
            )
          // Default surfaces are used as starting point for blended ones.
          : null,
    );
    // We on purpose shadow deprecated this.useSubThemesData that has
    // been deprecated, and set it it true if a none null subThemesData was
    // provided.
    final bool useSubThemes = subThemesData != null;
    // Use passed in sub-theme config data, or a default one, if none given.
    final FlexSubThemesData subTheme =
        subThemesData ?? const FlexSubThemesData();
    // Effective blend level for the onColors.
    int onBlendLevel = useSubThemes ? subTheme.blendOnLevel : 0;
    assert(
        onBlendLevel >= 0 && onBlendLevel <= 40,
        'Only onBlendLevel:s from 0 to 40 '
        'are allowed. Very high alpha blend levels may not produce results '
        'that are visually very appealing or useful.');
    // If above happens in none debug mode, use 0, no blends.
    if (onBlendLevel < 0 || onBlendLevel > 40) onBlendLevel = 0;

    // Get alpha blend values for used mode, on blend level and brightness,
    // used for onContainers and onSurface and onBackground.
    final _AlphaValues alphaOnValue = useSubThemes
        ? _AlphaValues.getAlphas(
            surfaceMode ?? FlexSurfaceMode.highScaffoldLowSurfaces,
            onBlendLevel)
        : const _AlphaValues();
    // Get alpha blend values for used mode, on blend level and brightness,
    // used for onPrimary, onSecondary, onTertiary and onError.
    final _AlphaValues alphaOnMain = useSubThemes && subTheme.blendOnColors
        ? _AlphaValues.getAlphas(
            surfaceMode ?? FlexSurfaceMode.highScaffoldLowSurfaces,
            onBlendLevel)
        : const _AlphaValues();
    // Determine the input surface and background colors.
    final Color inputSurface = surface ?? surfaceSchemeColors.surface;
    final Color inputBackground = background ?? surfaceSchemeColors.background;
    final FlexSchemeOnColors onColors = FlexSchemeOnColors.from(
      primary: effectiveColors.primary,
      primaryContainer: effectiveColors.primaryContainer,
      secondary: effectiveColors.secondary,
      secondaryContainer: effectiveColors.secondaryContainer,
      tertiary: effectiveColors.tertiary,
      tertiaryContainer: effectiveColors.tertiaryContainer,
      surface: inputSurface,
      surfaceVariant: surfaceSchemeColors.surfaceVariant,
      inverseSurface: surfaceSchemeColors.inverseSurface,
      background: inputBackground,
      error: effectiveColors.error!,
      errorContainer: effectiveColors.errorContainer,
      onPrimary: onPrimary ??
          (seed.useKeyColors && seed.keepPrimary
              ? null
              : seedScheme?.onPrimary) ??
          colorScheme?.onPrimary,
      onPrimaryContainer: onPrimaryContainer ??
          (seed.useKeyColors && seed.keepPrimaryContainer
              ? null
              : seedScheme?.onPrimaryContainer) ??
          colorScheme?.onPrimaryContainer,
      onSecondary: onSecondary ??
          (seed.useKeyColors && seed.keepSecondary
              ? null
              : seedScheme?.onSecondary) ??
          colorScheme?.onSecondary,
      onSecondaryContainer: onSecondaryContainer ??
          (seed.useKeyColors && seed.keepSecondaryContainer
              ? null
              : seedScheme?.onSecondaryContainer) ??
          colorScheme?.onSecondaryContainer,
      onTertiary: onTertiary ??
          (seed.useKeyColors && seed.keepTertiary
              ? null
              : seedScheme?.onTertiary) ??
          colorScheme?.onTertiary,
      onTertiaryContainer: onTertiaryContainer ??
          (seed.useKeyColors && seed.keepTertiaryContainer
              ? null
              : seedScheme?.onTertiaryContainer) ??
          colorScheme?.onTertiaryContainer,
      onSurface: onSurface ?? seedScheme?.onSurface ?? colorScheme?.onSurface,
      onSurfaceVariant:
          seedScheme?.onSurfaceVariant ?? colorScheme?.onSurfaceVariant,
      onInverseSurface:
          seedScheme?.onInverseSurface ?? colorScheme?.onInverseSurface,
      onBackground:
          onBackground ?? seedScheme?.onBackground ?? colorScheme?.onBackground,
      onError: onError ?? seedScheme?.onError ?? colorScheme?.onError,
      onErrorContainer: seedScheme?.onError ?? colorScheme?.onErrorContainer,
      primaryAlpha: alphaOnMain.primaryAlpha,
      primaryContainerAlpha: alphaOnValue.primaryContainerAlpha,
      secondaryAlpha: alphaOnMain.secondaryAlpha,
      secondaryContainerAlpha: alphaOnValue.secondaryContainerAlpha,
      tertiaryAlpha: alphaOnMain.tertiaryAlpha,
      tertiaryContainerAlpha: alphaOnValue.tertiaryContainerAlpha,
      surfaceAlpha: alphaOnValue.surfaceAlpha,
      surfaceVariantAlpha: alphaOnValue.surfaceVariantAlpha,
      inverseSurfaceAlpha: alphaOnValue.inverseSurfaceAlpha,
      backgroundAlpha: alphaOnValue.backgroundAlpha,
      errorAlpha: alphaOnMain.errorAlpha,
      errorContainerAlpha: alphaOnValue.errorContainerAlpha,
    );
    // Determine effective surface color.
    // Surface is used e.g. by Card and bottom appbar.
    // If light is white, we make a lighter than normal surface. If not
    // light is white, we use provided surface color, or computed one.
    final Color effectiveSurfaceColor =
        lightIsWhite ? inputSurface.lighten(5) : inputSurface;
    final Color effectiveSurfaceVariantColor = lightIsWhite
        ? surfaceSchemeColors.surfaceVariant.lighten(5)
        : surfaceSchemeColors.surfaceVariant;
    final Color effectiveInverseSurfaceColor = lightIsWhite
        ? surfaceSchemeColors.inverseSurface.darken(5)
        : surfaceSchemeColors.inverseSurface;
    // Determine effective background color.
    // Used e.g. by drawer, nav rail, side menu and bottom bar.
    // If light is white, we make a lighter than normal background. If not
    // light is white, we use provided background color, or computed one.
    final Color effectiveBackgroundColor =
        lightIsWhite ? inputBackground.lighten(5) : inputBackground;
    // Determine effective dialog background color.
    // If light is white, we use lighter than normal. If not,
    // we use dialog provided background color, or computed one.
    // The provided dialog background color overrides factory surface behavior,
    // but is impacted by true black mode for a darker effect.
    final Color effectiveDialogBackground = lightIsWhite
        ? dialogBackground?.lighten(5) ??
            surfaceSchemeColors.dialogBackground.lighten(5)
        : dialogBackground ?? surfaceSchemeColors.dialogBackground;

    // Compute the effective ColorScheme based on all selection options.
    final ColorScheme effectiveColorScheme = seedScheme?.copyWith(
          // We made a seeded color scheme, we use it as given but set
          // override values for props we have not handled via FCS direct
          // props further below. We don't adjust onColors for
          // surfaceVariant and inverseSurface on purpose.
          surfaceVariant: effectiveSurfaceVariantColor,
          inverseSurface: effectiveInverseSurfaceColor,
          surfaceTint: surfaceTint,
        ) ??
        // We had a colorScheme passed in, we use as passed in, but set
        // override values for props we have not handled via FCS direct
        // props further below.
        colorScheme?.copyWith(
          surfaceVariant: effectiveSurfaceVariantColor,
          onSurfaceVariant: onColors.onSurfaceVariant,
          inverseSurface: effectiveInverseSurfaceColor,
          onInverseSurface: onColors.onInverseSurface,
          surfaceTint: surfaceTint,
        ) ??
        // In order to avoid using a ColorScheme.light that sets
        // some opinionated defaults on deprecated members that we do not
        // want, we make a full one matching the target. Values that
        // exist as direct properties in FlexColorScheme, will actually
        // be used via them further below, but we need this ColorScheme
        // to provide the properties we are not handling via FCS
        // constructor. An alternative would be to add missing ColorScheme
        // properties to FlexColorScheme as direct override properties,
        // might do so later.
        ColorScheme(
          brightness: Brightness.light,
          primary: effectiveColors.primary,
          onPrimary: onColors.onPrimary,
          primaryContainer: effectiveColors.primaryContainer,
          onPrimaryContainer: onColors.onPrimaryContainer,
          secondary: effectiveColors.secondary,
          onSecondary: onColors.onSecondary,
          secondaryContainer: effectiveColors.secondaryContainer,
          onSecondaryContainer: onColors.onSecondaryContainer,
          tertiary: effectiveColors.tertiary,
          onTertiary: onColors.onTertiary,
          tertiaryContainer: effectiveColors.tertiaryContainer,
          onTertiaryContainer: onColors.onTertiaryContainer,
          error: useMaterial3ErrorColors && !seed.useKeyColors
              ? FlexColor.material3LightError
              : effectiveColors.error!,
          onError: useMaterial3ErrorColors && !seed.useKeyColors
              ? FlexColor.material3LightOnError
              : onColors.onError,
          errorContainer: useMaterial3ErrorColors && !seed.useKeyColors
              ? FlexColor.material3LightErrorContainer
              : effectiveColors.errorContainer!,
          onErrorContainer: useMaterial3ErrorColors && !seed.useKeyColors
              ? FlexColor.material3LightOnErrorContainer
              : onColors.onErrorContainer,
          background: effectiveBackgroundColor,
          onBackground: onColors.onBackground,
          surface: effectiveSurfaceColor,
          onSurface: onColors.onSurface,
          surfaceVariant: effectiveSurfaceVariantColor,
          onSurfaceVariant: onColors.onSurfaceVariant,
          inverseSurface: effectiveInverseSurfaceColor,
          onInverseSurface: onColors.onInverseSurface,
          inversePrimary: _inversePrimary(
              Brightness.light, effectiveColors.primary, effectiveSurfaceColor),
          shadow: Colors.black,
          outline: _outlineColor(Brightness.light, onColors.onBackground),
          surfaceTint: surfaceTint ?? effectiveColors.primary,
        );

    // Determine the effective AppBar color:
    // - First priority, passed in color value.
    Color? effectiveAppBarColor = appBarBackground;
    // - Second priority, sub-theme based scheme color.
    effectiveAppBarColor ??=
        useSubThemes && subTheme.appBarBackgroundSchemeColor != null
            ? FlexSubThemes.schemeColor(
                subTheme.appBarBackgroundSchemeColor!, effectiveColorScheme)
            : null;
    // Third priority [appBarStyle] based.
    if (effectiveAppBarColor == null) {
      switch (appBarStyle) {
        case FlexAppBarStyle.primary:
          effectiveAppBarColor = effectiveColors.primary;
          break;
        case FlexAppBarStyle.material:
          effectiveAppBarColor = FlexColor.materialLightSurface;
          break;
        case FlexAppBarStyle.background:
          effectiveAppBarColor = effectiveBackgroundColor;
          break;
        case FlexAppBarStyle.surface:
          effectiveAppBarColor = effectiveSurfaceColor;
          break;
        case FlexAppBarStyle.custom:
          effectiveAppBarColor =
              effectiveColors.appBarColor ?? effectiveColors.primary;
          break;
      }
    }
    // Apply specified opacity on on the resulting color.
    effectiveAppBarColor = effectiveAppBarColor.withOpacity(appBarOpacity);

    return FlexColorScheme(
      colorScheme: effectiveColorScheme,
      // This is the light theme factory so we always set brightness to light.
      brightness: Brightness.light,
      // Primary colors for the application
      primary: effectiveColors.primary,
      primaryContainer: effectiveColors.primaryContainer,
      // The secondary colors for the application.
      secondary: effectiveColors.secondary,
      secondaryContainer: effectiveColors.secondaryContainer,
      // The tertiary colors for the application.
      tertiary: effectiveColors.tertiary,
      tertiaryContainer: effectiveColors.tertiaryContainer,
      // Surface is used e.g. by Card and bottom appbar.
      surface: effectiveSurfaceColor,
      // Background is used e.g. by drawer and bottom nav bar.
      background: effectiveBackgroundColor,
      // Color of the scaffold background.
      scaffoldBackground: scaffoldBackground ??
          (lightIsWhite
              ? Colors.white
              : surfaceSchemeColors.scaffoldBackground),
      // Color of dialog background elements, a passed in dialogBackground
      // color will override the factory style, if provided.
      dialogBackground: effectiveDialogBackground,
      // Set app bar background to effective background color.
      appBarBackground: effectiveAppBarColor,
      // Effective error color and null fallback.
      error: useMaterial3ErrorColors && !seed.useKeyColors
          ? FlexColor.material3LightError
          : effectiveColors.error ?? FlexColor.materialLightError,
      onPrimary: onColors.onPrimary,
      onPrimaryContainer: onColors.onPrimaryContainer,
      onSecondary: onColors.onSecondary,
      onSecondaryContainer: onColors.onSecondaryContainer,
      onTertiary: onColors.onTertiary,
      onTertiaryContainer: onColors.onTertiaryContainer,
      onSurface: onColors.onSurface,
      onBackground: onColors.onBackground,
      onError: useMaterial3ErrorColors && !seed.useKeyColors
          ? FlexColor.material3LightOnError
          : onColors.onError,
      surfaceTint: surfaceTint,
      tabBarStyle: tabBarStyle,
      appBarElevation: appBarElevation,
      bottomAppBarElevation: effectiveBottomAppBarElevation,
      tooltipsMatchBackground: tooltipsMatchBackground,
      transparentStatusBar: transparentStatusBar,
      visualDensity: visualDensity,
      textTheme: textTheme,
      primaryTextTheme: primaryTextTheme,
      fontFamily: fontFamily,
      platform: platform,
      typography: typography,
      applyElevationOverlayColor: applyElevationOverlayColor,
      subThemesData: subThemesData,
      useMaterial3: useMaterial3,
      extensions: extensions,
    );
  }

  //****************************************************************************
  //
  // DARK COLOR SCHEME AND THEME DEFINITIONS
  //
  // Factory FlexColorScheme.dark
  //
  //****************************************************************************

  /// Creates a [FlexColorScheme] for dark theme mode.
  ///
  /// The factory has no required [FlexSchemeColor] properties, but typically
  /// a [FlexScheme] enum [scheme] value would be provided to use a pre-defined
  /// color scheme.
  ///
  /// As a second alternative the [FlexSchemeColor] class [colors] property
  /// can be used to define custom scheme colors, that can be created with just
  /// one color property by using the factory [FlexSchemeColor.from].
  ///
  /// As a third option you can provide a complete [ColorScheme] in
  /// [colorScheme] and the custom colors for the theme will be based on that
  /// scheme. Since this is the light theme factory the brightness value in used
  /// [colorScheme] is ignored and resulting effective theme and color scheme
  /// will always be light. Make sure you use colors in your color scheme that
  /// are actually colors for a light theme.
  ///
  /// The factory can produce blended surface colors, and also has other
  /// parameters that may impact the effective color scheme used by final theme,
  /// even when a [colorScheme] are provided. The [FlexColorScheme.toScheme]
  /// will give you the effective color scheme that will also be used
  /// when producing [ThemeData] from [FlexColorScheme] and its factories
  /// with [FlexColorScheme.toTheme].
  ///
  /// The factory contains a large number of other properties that can be used
  /// to create beautiful themes by just adjusting a few behavior properties.
  ///
  /// To activate using opinionated sub themes that further refines the produced
  /// theme, set [useSubThemes] to true and optionally pass in a
  /// [FlexSubThemesData] to [subThemesData] to use short cut properties to
  /// setup additional features in the sub-themes.
  ///
  /// Material 3 guide introduces a new color system with key colors and tonal
  /// palettes, see
  /// https://m3.material.io/styles/color/the-color-system/key-colors-tones.
  ///
  /// You can opt-in on using this new M3 color system by creating your tonal
  /// theme colors using the effective [primary], [secondary] and [tertiary]
  /// colors in the factory, as key colors to create tonal palettes for
  /// these main Material 3 color palettes.
  /// Colors from these key color seed generated palettes will then be used as
  /// color tones for the produce [ColorScheme], as defined by the Material 3
  /// design guide. By studying the Flutter SDK [ColorScheme.from] factory you
  /// can see which color tone from what key color is used where.
  /// [FlexColorScheme] uses the same assignments for the tones to the
  /// generated [ColorScheme] when you opt in using Material 3 tonal palettes.
  ///
  /// The [FlexColorScheme] light and dark factory offer more control over the
  /// seed generation setup. With [ColorScheme.from] you can only generate the
  /// [ColorScheme] from one key color, the primary color. With
  /// [FlexColorScheme] factories  you can use separate key colors for
  /// [secondary] and [tertiary] from the [primary] color, to make their
  /// tonal palettes. The effective colors in your [FlexColorScheme] for these
  /// color properties are used as key color inputs when you provide a
  /// [FlexKeyColors] via [keyColors] and enable it by setting
  /// [FlexKeyColors.useKeyColors] to true, which it is in its default
  /// constructor, so to enable it you can just pass in a default
  /// FlexKeyColors() to [keyColors].
  ///
  /// By setting [FlexKeyColors.useSecondary] or
  /// [FlexKeyColors.useTertiary] to false, the corresponding effective colors
  /// in [FlexColorScheme] will not be used as keys for corresponding
  /// [TonalPalette]. If one is off, its tonal palette will instead be based on
  /// the primary color as key. If both are false, the [FlexColorScheme.light]
  /// seeding algorithm becomes the same as using [ColorScheme.from]. The
  /// primary color is always used as seed color when key color seeding is
  /// enabled with [FlexKeyColors.useKeyColors] set to true.
  ///
  /// You can also opt to keep selected effective main colors, primary,
  /// secondary, tertiary and their containers, in your [FlexColorScheme] as
  /// their effective color, even when you enable key color based
  /// seeded tonal palette based ColorScheme output. You do this by
  /// setting [FlexKeyColors.keepPrimary], [FlexKeyColors.keepSecondary] etc to
  /// true, for each color property where you want to keep its exact color value
  /// as defined, but otherwise may be OK with using key seeded color values.
  ///
  /// You can use this feature if you for example want to use an exact
  /// predefined primary brand color in light mode, but are OK with all other
  /// colors using tones derived from its Material 3 tonal palette.
  ///
  /// When you use key color based seeded theme generation, the used key inputs
  /// for primary, secondary and tertiary are only used to set and generate the
  /// tone of the palette used for each colors tonal palette. You will rarely
  /// see the same color on that actual, primary, secondary and tertiary color
  /// in the produced [ColorScheme], unless you lock them down with the "keep"
  /// properties.
  ///
  /// The same tonal palette should typically be used for both
  /// light and dark mode colors. Under the hood [FlexColorScheme] selects the
  /// right color tone from the tonal palette, which is different for light and
  /// dark mode. For a matched light and dark theme, you should use the same
  /// input key color. When you use [FlexColorScheme.light] and
  /// [FlexColorScheme.dark] and the [FlexScheme] enum based [scheme] property,
  /// to use a built-in color scheme, it automatically uses also its
  /// predefined light theme mode defined colors as the key colors for
  /// primary, secondary and tertiary in dark mode, to ensure that the produced
  /// [ColorScheme] is using same tonal palette, but only different tones from
  /// it  for light and dark mode.
  ///
  /// When you use [colors], [colorScheme] or direct override color properties
  /// [primary], [secondary] or [tertiary] in the factories, these effective
  /// colors are used directly as key color inputs. It is then up to
  /// you to decide and design if you use the same key color for tonal palette
  /// generation in light and dark mode.
  ///
  /// If you use [colorScheme] or pass in [primary], [secondary] or
  /// [tertiary], and enable using [keyColors] the generated scheme will first
  /// use color from passed in direct color properties [primary], [secondary]
  /// or [tertiary], as key colors, then the same ones from the passed in
  /// [colorScheme] when it generates the output [ColorScheme] using the active
  /// [FlexKeyColors] setup.
  ///
  /// The generated [ColorScheme]'s properties will override all color
  /// properties that were passed in  via a [colorScheme], except those locked
  /// via the `keep` properties in [FlexKeyColors].
  ///
  /// If you assign override colors via direct color properties for the main
  /// colors [primary], [secondary] or [tertiary] and their containers, they
  /// will also only override the generated resulting [ColorScheme] if the
  /// the `keep` properties are set in [FlexKeyColors]. Other color properties
  /// that exist as both direct color properties and as a color in the
  /// generated resulting [ColorScheme], will always override the generated
  /// color property if they are assigned.
  ///
  /// Normally if you provide an entire [colorScheme] to [FlexColorScheme] it
  /// is typically because you already have a scheme that you want to use as is,
  /// then don't enable [keyColors] or any blends. It is however possible to
  /// apply both blends to passed in [colorScheme] surfaces or to just use
  /// the [primary], [secondary] or [tertiary] colors in passed in [colorScheme]
  /// as [keyColors] to generate an entirely new [ColorScheme] from the passed
  /// in colors, using [primary], [secondary] or [tertiary] as keys.
  factory FlexColorScheme.dark({
    /// The [FlexSchemeColor] used to create the dark [FlexColorScheme] from.
    ///
    /// You can use predefined [FlexSchemeColor] values from [FlexColor] or
    /// [FlexColor.schemes] map or define your own colors with
    /// [FlexSchemeColor] or [FlexSchemeColor.from].
    ///
    /// For using built-in color schemes, the convenience shortcut to select
    /// it with the [scheme] property is recommended and leaving [colors]
    /// undefined. If both are specified the scheme colors defined by [colors]
    /// are used. If both are null then [scheme] defaults to
    /// [FlexScheme.material], thus defining the resulting scheme.
    final FlexSchemeColor? colors,

    /// Use one of the built-in color schemes defined by enum [FlexScheme].
    ///
    /// Give it one of the enum values to use the scheme, like eg.
    /// [FlexScheme.mandyRed].
    ///
    /// To create custom color schemes use the [colors] property. If both
    /// [colors] and [scheme] are specified, the scheme defined by
    /// [colors] is used. If both are null, then [scheme] defaults to
    /// [FlexScheme.material].
    final FlexScheme? scheme,

    /// The overall [ColorScheme] based colors for the theme.
    ///
    /// This property provides a new way to define custom colors for
    /// [FlexColorScheme] and is available from version 4.2.0. It is useful if
    /// you already have a custom [ColorScheme] based color definition that
    /// you want to use with FlexColorScheme theming and its sub-theming
    /// capabilities. This will become particularly useful when using Material 3
    /// based design and its seed generated color schemes.
    ///
    /// If you provide both a [ColorScheme] and some individual direct property
    /// values that also exist in a [ColorScheme], the individual property
    /// values will override the corresponding ones in your [ColorScheme].
    ///
    /// If you do not define a [colorScheme], the used colors will be determined
    /// by the [colors] and [scheme] properties. However, when a [colorScheme]
    /// is defined it takes precedence. The [brightness] in the provided
    /// [colorScheme] is always ignored and set to [Brightness.light] since this
    /// is the light theme mode factory. Make sure the colors used in your color
    /// scheme are intended for a light theme.
    ///
    /// If you define a [surfaceMode] and set [blendLevel] > 0, then [surface]
    /// and [background] colors in the provided [colorScheme] will be overridden
    /// by the computed color branded surfaces. If your [colorScheme] already
    /// contains branded surface colors, then keep [blendLevel] = 0 to continue
    /// using them.
    ///
    /// If you use [lightIsWhite] factory feature, it will also override your
    /// [colorScheme] based [surface] and [background] properties and make them
    /// 8% lighter.
    ///
    /// If you opt in on using sub themes with [useSubThemes] and have set
    /// [subThemesData.blendOnColors] to true and have defined [surfaceMode]
    /// and set [blendLevel] > 0, then the effective color scheme based on
    /// colors onPrimary, onSecondary, onError, onSurface and onBackground will
    /// be changed accordingly too.
    ///
    /// The [colorScheme] colors are also included and affected by factory
    /// properties [usedColors] and [swapColors] and included in their behavior.
    ///
    /// The [FlexColorScheme]'s effective [ColorScheme] can be returned with
    /// [toScheme]. This will always get you a complete color scheme, including
    /// calculated and derived color values, which is particularly useful when
    /// using the [FlexColorScheme.light] and [FlexColorScheme.dark] factories
    /// to compute color scheme branded surface colors for you. The effective
    /// [ColorScheme] for your theme is often needed if you want to create
    /// custom sub-themes that should use the colors from the scheme using none
    /// default color assignments from the color scheme.
    final ColorScheme? colorScheme,

    /// The number of the six main scheme colors to be used when creating
    /// effective [ColorScheme].
    ///
    /// This is a convenience property that allows you to vary which colors to
    /// use of the primary, secondary and tertiary colors and their container
    /// colors when FlexSchemeColor creates its effective [ColorScheme] from
    /// the input colors. The integer number corresponds to using:
    ///
    /// * 1 = Only the primary color
    /// * 2 = Primary & Secondary colors
    /// * 3 = Primary + container & Secondary colors
    /// * 4 = Primary + container & Secondary + container
    /// * 5 = Primary + container & Secondary + container & tertiary colors
    /// * 6 = Primary + container & Secondary + container & tertiary + container
    ///
    /// By default the value is 6 and all main scheme colors in
    /// `FlexSchemeColor` are used.
    ///
    /// When the value is 1, the result is the same as if we would have
    /// created the colors with [FlexSchemeColor.from] by only giving it the
    /// required primary color. With 2, it is equivalent to as if we would have
    /// given it only the primary and secondary colors, and so on.
    /// This property makes it possible to simulate and change the resulting
    /// [FlexColorScheme] to as if you would have specified 1, 2, 3 ... 6 of
    /// the colors. If your used [FlexColorScheme] `colors` was actually created
    /// with [FlexSchemeColor.from] with only the primary color defined, then
    /// changing the value from 6 ... 3, 2 or 1, will all produce the same
    /// effective scheme as the computed values will be the same as the
    /// [FlexSchemeColor.from] is using to compute any main missing scheme
    /// color values.
    final int usedColors = 6,

    /// Blends theme colors into surfaces and backgrounds.
    ///
    /// If defined, used mode overrides the older [surfaceStyle]
    /// property setting. Prefer using [surfaceMode] over [surfaceStyle],
    /// it offers more color branded surface modes and separate control over
    /// the used branding level via the separate [blendLevel] property.
    ///
    /// The mode [FlexSurfaceMode.highBackgroundLowScaffold] can be used to
    /// replace the style that was produced when using old and removed
    /// `FlexColorScheme.surfaceStyle` enum property `FlexSurface` in
    /// [FlexColorScheme.light] and [FlexColorScheme.dark] before version 4.
    ///
    /// The mode [FlexSurfaceMode.highBackgroundLowScaffold] uses the same
    /// design concept as the only style offered via removed `FlexSurface`
    /// in `FlexColorScheme.surfaceStyle` that was in use before version 4,
    /// and deprecated in version 4.2 and removed in version 5.0.0.
    ///
    /// By adjusting the [FlexColorScheme.blendLevel] property and using this
    /// style, you can find a similar visual effect when using
    /// [FlexSurfaceMode.highBackgroundLowScaffold] with the following values
    /// when matching match most prominent blended [ColorScheme.background]
    /// color.
    ///
    /// In light theme mode:
    ///
    /// * [FlexSurface.material] 0% : blendLevel = 0
    /// * [FlexSurface.light]    2% : blendLevel = 3...4
    /// * [FlexSurface.medium]   4% : blendLevel = 7
    /// * [FlexSurface.strong]   6% : blendLevel = 10
    /// * [FlexSurface.heavy]    8% : blendLevel = 13...14
    ///
    /// In dark theme mode:
    ///
    /// * [FlexSurface.material] 0% : blendLevel = 0
    /// * [FlexSurface.light]    5% : blendLevel = 8
    /// * [FlexSurface.medium]   8% : blendLevel = 13...14
    /// * [FlexSurface.strong]  11% : blendLevel = 19
    /// * [FlexSurface.heavy]   14% : blendLevel = 23
    ///
    /// Since there it is not the same relationship between background and
    /// surface, when using the older [FlexSurface] based style, that uses
    /// individually tuned relationships. The old and new designs do never
    /// align exactly at any blendLevel. The above values produce visually
    /// similar results for the most prominent background color blend.
    ///
    /// To get elevation overlay color in dark themes on all surfaces used by
    /// [Material], use one of the modes where background and dialog color
    /// equals the blend strength on surface color, like [level],
    /// [levelSurfacesLowScaffold], [highScaffoldLowSurfaces] and
    /// [highScaffoldLowSurfaces]. Other modes will only use
    /// elevation overlay if their background happens to be equal to resulting
    /// colorScheme.surface color. For more information
    /// see issue: https://github.com/flutter/flutter/issues/90353
    ///
    /// When using very strong surface branding in dark mode, having an overlay
    /// elevation color in dark mode is less critical, since the elevation
    /// becomes partially visible via shadows and the surface may even have
    /// another color tint if using e.g. [levelSurfacesLowScaffoldVariantDialog]
    /// or [highScaffoldLowSurfacesVariantDialog].
    ///
    /// If values for the properties [surface], [background],
    /// [dialogBackground] or [scaffoldBackground] are given,
    /// they are used instead of values that would be assigned based
    /// on used [FlexSurfaceMode] via [surfaceMode] or [FlexSurface] in
    /// this [surfaceMode].
    ///
    /// Defaults to using [FlexSurfaceMode.highScaffoldLowSurfaces] when
    /// [blendLevel] > 0.
    final FlexSurfaceMode? surfaceMode,

    /// Sets the blend level strength used by the surface mode.
    ///
    /// The blend level is the integer decimal value of the alpha value
    /// used in the alpha blend function. It mixes one color with another
    /// by using alpha opacity value in the color of a surface put on top of
    /// another surface with opaque color and returns the result as one opaque
    /// color.
    ///
    /// Defaults to 0.
    final int blendLevel = 0,

    /// Style used to define the themed color of the [AppBar] background color.
    ///
    /// Defaults to [FlexAppBarStyle.material] which produces the same results
    /// as a Flutter standard dark [ThemeData.from] by tying the app bar color
    /// to the surface color.
    final FlexAppBarStyle appBarStyle = FlexAppBarStyle.material,

    /// Themed [AppBar] opacity.
    ///
    /// The opacity is applied to the effective AppBar color, which may be from
    /// used [appBarStyle], that gets its color selection from used [scheme]
    /// or [colors]. Or that color may have been overridden by AppBar sub-theme
    /// and there selected [SchemeColor] based color.
    /// Lastly and with highest priority it may be from here directly supplied
    /// [appBarBackground] color.
    ///
    /// A useful opacity range is from 0.85 to 0.95 when using the [Scaffold]
    /// property [extendBodyBehindAppBar] set to true, to partially show
    /// scrolling content behind the app bar. To use more opacity, in a way
    /// that the AppBar does not become too transparent, you also need to blur
    /// the background to create a frosted glass effect. This cannot
    /// be made with only theming, you need a custom AppBar Widget for that.
    /// Frosted glass UI effect is thus beyond the scope of what
    /// FlexColorScheme can do alone as it only affects ThemeData.
    ///
    /// Defaults to 1, fully opaque, no transparency. Must be from 0 to 1.
    final double appBarOpacity = 1,

    /// When set to true, it makes the status bar on Android the same color as
    /// the rest of the AppBar.
    ///
    /// Defaults to true.
    ///
    /// When true, the AppBar in Android mimics the look of one-toned AppBar's
    /// typically used on iOS. Set to `false`, to revert back and use
    /// Android's default two-toned look. If true the status bar area is
    /// actually also transparent so that if the app bar is also translucent,
    /// content that scrolls behind it, is also visible behind the status
    /// bar area.
    final bool transparentStatusBar = true,

    /// The themed elevation for the app bar.
    ///
    /// Default to 0. The 0 elevation is an iOs style
    /// influenced opinionated choice, but it can easily be adjusted for the
    /// theme with this property.
    final double appBarElevation = 0,

    /// The themed elevation for the bottom app bar.
    ///
    /// If null, defaults to the value given to the `appBarElevation` elevation.
    final double? bottomAppBarElevation,

    /// Select preferred themed style for the [TabBarTheme].
    ///
    /// By default the [TabBarTheme] is made to fit with the style of the
    /// [AppBar], via default value [FlexTabBarStyle.forAppBar].
    ///
    /// When setting this to [FlexTabBarStyle.forBackground], it will default
    /// to a theme that uses the color scheme and fits on background color,
    /// which typically also on works surface and scaffoldBackground color.
    /// This TabBarTheme style is useful if you primarily intended to use the
    /// TabBar in a Scaffold, Dialog, Drawer or Side panel on their background
    /// colors.
    final FlexTabBarStyle tabBarStyle = FlexTabBarStyle.forAppBar,

    /// The color displayed most frequently across your app’s screens and
    /// components.
    ///
    /// When using the factory this is an override color for the color that
    /// would be used based on the corresponding color property defined in
    /// [FlexSchemeColor] [colors] or for this color defined when using a
    /// pre-defined color scheme based on [FlexScheme] [scheme] property, or
    /// if a [colorScheme] was provided it will override the same color in it
    /// as well.
    ///
    /// You can use this property for convenience if you want to override the
    /// color that this scheme color gets via the factory behavior.
    ///
    /// This override color is included and affected by factory
    /// properties [usedColors] and [swapColors] and included in their behavior.
    ///
    /// Defaults to null.
    final Color? primary,

    /// A color used for elements needing less emphasis than [primary].
    ///
    /// When using the factory this is an override color for the color that
    /// would be used based on the corresponding color property defined in
    /// [FlexSchemeColor] [colors] or for this color defined when using a
    /// pre-defined color scheme based on [FlexScheme] [scheme] property, or
    /// if a [colorScheme] was provided it will override the same color in it
    /// as well.
    ///
    /// You can use this property for convenience if you want to override the
    /// color that this scheme color gets via the factory behavior.
    ///
    /// The override color is included and affected by factory
    /// properties [usedColors] and [swapColors] and included in their behavior.
    ///
    /// Defaults to null.
    final Color? primaryContainer,

    /// A darker version of the primary color.
    ///
    /// In Flutter SDK the `primaryVariant` color is only used by [SnackBar]
    /// button color in dark theme mode as a part of predefined widget behavior.
    /// If you provide a custom [SnackBarThemeData] where you define
    /// [SnackBarThemeData.actionTextColor] to [primary] or [secondary], this
    /// color property becomes a good property to use if you need a custom color
    /// for custom widgets accessible via your application's ThemeData, that is
    /// not used as default color by any other built-in widgets. This applies
    /// to Flutter 2.8.1 and earlier versions.
    ///
    /// The property is deprecated in Flutter SDK and was replaced
    /// by a new property called [primaryContainer]. It is deprecated from
    /// master v2.6.0-0.0.pre, and in stable (2.10.0).
    /// See https://github.com/flutter/flutter/issues/89852.
    ///
    /// When using the factory this is an override color for the color that
    /// would be used based on the corresponding color property defined in
    /// [FlexSchemeColor] [colors] or for this color defined when using a
    /// pre-defined color scheme based on [FlexScheme] [scheme] property, or
    /// if a [colorScheme] was provided it will override the same color in it
    /// as well.
    ///
    /// You can use this property for convenience if you want to override the
    /// color that this scheme color gets via the factory behavior.
    ///
    /// The override color is included and affected by factory
    /// properties [usedColors] and [swapColors] and included in their behavior.
    ///
    /// Defaults to null.
    @Deprecated('Replaced with `primaryContainer`, after version 4.2.0, '
        'due to deprecation in Flutter master from 2.10.0')
        final Color? primaryVariant,

    /// An accent color that, when used sparingly, calls attention to parts
    /// of your app.
    ///
    /// When using the factory this is an override color for the color that
    /// would be used based on the corresponding color property defined in
    /// [FlexSchemeColor] [colors] or for this color defined when using a
    /// pre-defined color scheme based on [FlexScheme] [scheme] property, or
    /// if a [colorScheme] was provided it will override the same color in it
    /// as well.
    ///
    /// You can use this property for convenience if you want to override the
    /// color that this scheme color gets via the factory behavior.
    ///
    /// The override color is included and affected by factory properties
    /// [usedColors] and [swapColors] and included in their behavior.
    ///
    /// Defaults to null.
    final Color? secondary,

    /// A color used for elements needing less emphasis than [secondary].
    ///
    /// When using the factory this is an override color for the color that
    /// would be used based on the corresponding color property defined in
    /// [FlexSchemeColor] [colors] or for this color defined when using a
    /// pre-defined color scheme based on [FlexScheme] [scheme] property, or
    /// if a [colorScheme] was provided it will override the same color in it
    /// as well.
    ///
    /// You can use this property for convenience if you want to override the
    /// color that this scheme color gets via the factory behavior.
    ///
    /// The override color is included and affected by factory properties
    /// [usedColors] and [swapColors] and included in their behavior.
    ///
    /// Defaults to null.
    final Color? secondaryContainer,

    /// A darker version of the secondary color.
    ///
    /// In Flutter SDK the `secondaryVariant` color is not used by in any
    /// built-in widgets default themes or predefined widget behavior.
    /// It is an excellent property to use if you need a custom color for
    /// custom widgets accessible via your application's ThemeData, and that is
    /// not used as default color by any built-in widgets. So you are in
    /// Flutter 2.8.1 and earlier version free to set it to whatever color you
    /// need and not affect any built-in widgets theme based colors.
    ///
    /// The property is deprecated in Flutter SDK and was replaced
    /// by a new property called [secondaryContainer]. It is deprecated from
    /// master v2.6.0-0.0.pre, and in stable (2.10.0).
    /// See https://github.com/flutter/flutter/issues/89852.
    ///
    /// When using the factory this is an override color for the color that
    /// would be used based on the corresponding color property defined in
    /// [FlexSchemeColor] [colors] or for this color defined when using a
    /// pre-defined color scheme based on [FlexScheme] [scheme] property, or
    /// if a [colorScheme] was provided it will override the same color in it
    /// as well.
    ///
    /// You can use this property for convenience if you want to override the
    /// color that this scheme color gets via the factory behavior.
    ///
    /// The override color is included and affected by factory properties
    /// [usedColors] and [swapColors] and included in their behavior.
    ///
    /// Defaults to null.
    @Deprecated('Replaced with `secondaryContainer`, after version 4.2.0, '
        'due to deprecation in Flutter master from 2.10.0')
        final Color? secondaryVariant,

    /// A color used as a contrasting accent that can balance [primary]
    /// and [secondary] colors or bring heightened attention to an element,
    /// such as an input field.
    ///
    /// When using the factory this is an override color for the color that
    /// would be used based on the corresponding color property defined in
    /// [FlexSchemeColor] [colors] or for this color defined when using a
    /// pre-defined color scheme based on [FlexScheme] [scheme] property, or
    /// if a [colorScheme] was provided it will override the same color in it
    /// as well.
    ///
    /// You can use this property for convenience if you want to override the
    /// color that this scheme color gets via the factory behavior.
    ///
    /// The override color is included and affected by factory properties
    /// [usedColors] and [swapColors] and included in their behavior.
    ///
    /// Defaults to null.
    final Color? tertiary,

    /// A color used for elements needing less emphasis than [tertiary].
    ///
    /// When using the factory this is an override color for the color that
    /// would be used based on the corresponding color property defined in
    /// [FlexSchemeColor] [colors] or for this color defined when using a
    /// pre-defined color scheme based on [FlexScheme] [scheme] property, or
    /// if a [colorScheme] was provided it will override the same color in it
    /// as well.
    ///
    /// You can use this property for convenience if you want to override the
    /// color that this scheme color gets via the factory behavior.
    ///
    /// The override color is included and affected by factory properties
    /// [usedColors] and [swapColors] and included in their behavior.
    ///
    /// Defaults to null.
    final Color? tertiaryContainer,

    /// The color to use for input validation errors, e.g. for
    /// [InputDecoration.errorText].
    ///
    /// When using the factory this is an override color for the color that
    /// would be used based on the corresponding color property defined in
    /// [FlexSchemeColor] [colors] or for this color defined when using a
    /// pre-defined color scheme based on [FlexScheme] [scheme] property, or
    /// if a [colorScheme] was provided it will override the same color in it
    /// as well.
    ///
    /// You can use this property for convenience if you want to override the
    /// color that this scheme color gets via the factory behavior.
    final Color? error,

    /// The surface (background) color for widgets like [Card] and
    /// [BottomAppBar].
    ///
    /// The color is applied to [ThemeData.cardColor] and
    /// [ColorScheme.surface] in [ThemeData.colorScheme], it is also used
    /// by all [Material] of type [MaterialType.card].
    ///
    /// When using the factory this is an override color for the color that
    /// would be used based on mode defined by property
    /// [surfaceMode] [FlexSurfaceMode] enum or [surfaceStyle] enum
    /// [FlexSurface], or if a [colorScheme] was provided it will override the
    /// same color in it as well.
    ///
    /// Defaults to null.
    final Color? surface,

    /// A color that typically appears behind scrollable content.
    ///
    /// The color is applied to [ThemeData.canvasColor] and
    /// [ThemeData.backgroundColor], it is used eg by menu [Drawer] and by all
    /// [Material] of type [MaterialType.canvas].
    ///
    /// When using the factory this is an override color for the color that
    /// would be used based on mode defined by property
    /// [surfaceMode] [FlexSurfaceMode] enum or [surfaceStyle] enum
    /// [FlexSurface], or if a [colorScheme] was provided it will override the
    /// same color in it as well.
    ///
    /// Defaults to null.
    final Color? background,

    /// The color of the [Scaffold] background.
    ///
    /// The color is applied to [ThemeData.scaffoldBackgroundColor].
    ///
    /// When using the factory this is an override color for the color that
    /// would be used based on mode defined by property
    /// [surfaceMode] [FlexSurfaceMode] enum or [surfaceStyle] enum
    /// [FlexSurface].
    ///
    /// Defaults to null.
    final Color? scaffoldBackground,

    /// The background color of Dialog elements.
    ///
    /// When using the factory this is an override color for the color that
    /// would be used based on mode defined by property
    /// [surfaceMode] [FlexSurfaceMode] enum or [surfaceStyle] enum
    /// [FlexSurface].
    ///
    /// If you assign a background [SchemeColor] to [dialogBackgroundColor] in
    /// [FlexSubThemesData] and you have opted in on using component sub themes
    /// with [useSubThemes], then its selected scheme color will override this
    /// value.
    ///
    /// Defaults to null.
    final Color? dialogBackground,

    /// Background theme color for the [AppBar].
    ///
    /// When using the factory this is an override color for the color that
    /// would be used based on the corresponding color property defined in
    /// [FlexSchemeColor] [colors] or for this color defined when using a
    /// pre-defined color scheme based on [FlexScheme] `scheme` property and
    /// the [FlexAppBarStyle] [appBarStyle] property.
    ///
    /// Thus custom color will also override any scheme color based selection
    /// for the [AppBAr] in active used sub-themes.
    final Color? appBarBackground,

    /// A color that is clearly legible when drawn on [primary] color.
    ///
    /// To ensure that an app is accessible, a contrast ratio of 4.5:1 for
    /// [primary] and [onPrimary] is recommended. See
    /// <https://www.w3.org/TR/UNDERSTANDING-WCAG20/visual-audio-contrast-contrast.html>.
    ///
    /// When using this factory, this is an override color for the color that
    /// would be used based on the corresponding color property defined in
    /// [FlexSchemeColor] [colors] property or when using pre-defined color
    /// scheme based [FlexScheme] and its [scheme] property, including any
    /// used blend logic. If a [colorScheme] was provided with this
    /// corresponding color defined, this color property will override the
    /// same color in it as well.
    ///
    /// You can use this property for convenience if you want to override the
    /// color that this scheme color gets via the factory behavior.
    final Color? onPrimary,

    /// A color that's clearly legible when drawn on [primaryContainer.
    ///
    /// To ensure that an app is accessible, a contrast ratio between
    /// [primaryContainer] and [onPrimaryContainer] of at least 4.5:1
    /// is recommended. See
    /// <https://www.w3.org/TR/UNDERSTANDING-WCAG20/visual-audio-contrast-contrast.html>.
    ///
    /// When using this factory, this is an override color for the color that
    /// would be used based on the corresponding color property defined in
    /// [FlexSchemeColor] [colors] property or when using pre-defined color
    /// scheme based [FlexScheme] and its [scheme] property, including any
    /// used blend logic. If a [colorScheme] was provided with this
    /// corresponding color defined, this color property will override the
    /// same color in it as well.
    ///
    /// You can use this property for convenience if you want to override the
    /// color that this scheme color gets via the factory behavior.
    final Color? onPrimaryContainer,

    /// A color that is clearly legible when drawn on [secondary] color.
    ///
    /// To ensure that an app is accessible, a contrast ratio of 4.5:1 for
    /// [secondary] and [onSecondary] is recommended. See
    /// <https://www.w3.org/TR/UNDERSTANDING-WCAG20/visual-audio-contrast-contrast.html>.
    ///
    /// When using this factory, this is an override color for the color that
    /// would be used based on the corresponding color property defined in
    /// [FlexSchemeColor] [colors] property or when using pre-defined color
    /// scheme based [FlexScheme] and its [scheme] property, including any
    /// used blend logic. If a [colorScheme] was provided with this
    /// corresponding color defined, this color property will override the
    /// same color in it as well.
    ///
    /// You can use this property for convenience if you want to override the
    /// color that this scheme color gets via the factory behavior.
    final Color? onSecondary,

    /// A color that's clearly legible when drawn on [secondaryContainer].
    ///
    /// To ensure that an app is accessible, a contrast ratio between
    /// [secondaryContainer] and [onSecondaryContainer] of at least 4.5:1
    /// is recommended. See
    /// <https://www.w3.org/TR/UNDERSTANDING-WCAG20/visual-audio-contrast-contrast.html>.
    ///
    /// When using this factory, this is an override color for the color that
    /// would be used based on the corresponding color property defined in
    /// [FlexSchemeColor] [colors] property or when using pre-defined color
    /// scheme based [FlexScheme] and its [scheme] property, including any
    /// used blend logic. If a [colorScheme] was provided with this
    /// corresponding color defined, this color property will override the
    /// same color in it as well.
    ///
    /// You can use this property for convenience if you want to override the
    /// color that this scheme color gets via the factory behavior.
    final Color? onSecondaryContainer,

    /// A color that's clearly legible when drawn on [tertiary].
    ///
    /// To ensure that an app is accessible, a contrast ratio of 4.5:1 for
    /// [secondary] and [onSecondary] is recommended. See
    /// <https://www.w3.org/TR/UNDERSTANDING-WCAG20/visual-audio-contrast-contrast.html>.
    ///
    /// When using this factory, this is an override color for the color that
    /// would be used based on the corresponding color property defined in
    /// [FlexSchemeColor] [colors] property or when using pre-defined color
    /// scheme based [FlexScheme] and its [scheme] property, including any
    /// used blend logic. If a [colorScheme] was provided with this
    /// corresponding color defined, this color property will override the
    /// same color in it as well.
    ///
    /// You can use this property for convenience if you want to override the
    /// color that this scheme color gets via the factory behavior.
    final Color? onTertiary,

    /// A color that's clearly legible when drawn on [tertiaryContainer].
    ///
    /// To ensure that an app is accessible, a contrast ratio between
    /// [secondaryContainer] and [onSecondaryContainer] of at least 4.5:1
    /// is recommended. See
    /// <https://www.w3.org/TR/UNDERSTANDING-WCAG20/visual-audio-contrast-contrast.html>.
    ///
    /// When using this factory, this is an override color for the color that
    /// would be used based on the corresponding color property defined in
    /// [FlexSchemeColor] [colors] property or when using pre-defined color
    /// scheme based [FlexScheme] and its [scheme] property, including any
    /// used blend logic. If a [colorScheme] was provided with this
    /// corresponding color defined, this color property will override the
    /// same color in it as well.
    ///
    /// You can use this property for convenience if you want to override the
    /// color that this scheme color gets via the factory behavior.
    final Color? onTertiaryContainer,

    /// A color that is clearly legible when drawn on [surface] color.
    ///
    /// To ensure that an app is accessible, a contrast ratio of 4.5:1 for
    /// [surface] and [onSurface] is recommended. See
    /// <https://www.w3.org/TR/UNDERSTANDING-WCAG20/visual-audio-contrast-contrast.html>.
    ///
    /// When using this factory, this is an override color for the color that
    /// would be used based on the corresponding color property defined in
    /// [FlexSchemeColor] [colors] property or when using pre-defined color
    /// scheme based [FlexScheme] and its [scheme] property, including any
    /// used blend logic. If a [colorScheme] was provided with this
    /// corresponding color defined, this color property will override the
    /// same color in it as well.
    ///
    /// You can use this property for convenience if you want to override the
    /// color that this scheme color gets via the factory behavior.
    final Color? onSurface,

    /// A color that is clearly legible when drawn on [background] color.
    ///
    /// To ensure that an app is accessible, a contrast ratio of 4.5:1 for
    /// [background] and [onBackground] is recommended. See
    /// <https://www.w3.org/TR/UNDERSTANDING-WCAG20/visual-audio-contrast-contrast.html>.
    ///
    /// When using this factory, this is an override color for the color that
    /// would be used based on the corresponding color property defined in
    /// [FlexSchemeColor] [colors] property or when using pre-defined color
    /// scheme based [FlexScheme] and its [scheme] property, including any
    /// used blend logic. If a [colorScheme] was provided with this
    /// corresponding color defined, this color property will override the
    /// same color in it as well.
    ///
    /// You can use this property for convenience if you want to override the
    /// color that this scheme color gets via the factory behavior.
    final Color? onBackground,

    /// A color that is clearly legible when drawn on [error] color.
    ///
    /// To ensure that an app is accessible, a contrast ratio of 4.5:1 for
    /// [error] and [onError] is recommended. See
    /// <https://www.w3.org/TR/UNDERSTANDING-WCAG20/visual-audio-contrast-contrast.html>.
    ///
    /// When using this factory, this is an override color for the color that
    /// would be used based on the corresponding color property defined in
    /// [FlexSchemeColor] [colors] property or when using pre-defined color
    /// scheme based [FlexScheme] and its [scheme] property, including any
    /// used blend logic. If a [colorScheme] was provided with this
    /// corresponding color defined, this color property will override the
    /// same color in it as well.
    ///
    /// You can use this property for convenience if you want to override the
    /// color that this scheme color gets via the factory behavior.
    final Color? onError,

    /// A color used as an overlay on a surface color to indicate a component's
    /// elevation.
    ///
    /// You can use this property for convenience if you want to override the
    /// color that this scheme color gets via the factory behavior.
    /// If a [colorScheme] was provided where this corresponding color is
    /// defined, this color property will override the same color in it.
    ///
    /// This color is used by M3 for colored elevation, it is also used as the
    /// blend color for FlexColorScheme surface blends.
    ///
    /// If undefined it defaults to [primary] color.
    final Color? surfaceTint,

    /// Makes the dark theme backgrounds darker or even black.
    ///
    /// Scaffold background will become fully black, and other surfaces also get
    /// darker (8%), if using low blend levels they may become fully black too.
    final bool darkIsTrueBlack = false,

    /// When true, the primary and primary container colors will be swapped with
    /// their secondary counter parts.
    ///
    /// Set this flag to true if you want to make a theme where
    /// your primary and secondary colors are swapped, compared to how they
    /// are defined in the passed in color properties or used pre-defined
    /// color scheme.
    ///
    /// This is useful if you want to do this with the pre-defined
    /// schemes. If you are explicitly defining all your theme colors you can
    /// of course define them in any desired config. Even if you do
    /// that, this feature will still swap whatever colors you defined
    /// for primary and secondary. You can offer this feature as an easy end
    /// user modifiable theme option if you like. One usage possibility is to
    /// set `swapColors` to true only for the dark modem and use your color
    /// scheme the other way around only in dark mode.
    final bool swapColors = false,

    /// When true, tooltip background color will match the brightness of the
    /// theme's background color.
    ///
    /// By default Flutter's Material tooltips use a theme where the tooltip
    /// background color brightness is inverted in relation to the overall
    /// theme's background color.
    ///
    /// FlexColorScheme allows you to use a single
    /// toggle to invert this. Light tooltips on light background is e.g. the
    /// default style on Windows Desktop. You can use this toggle to use this
    /// style, or as a means to create a platform adaptive
    /// tooltip style, where the Material/Flutter style is used on devices and
    /// Web, but the inverted scheme is used on desktop platforms.
    ///
    /// Defaults to false, and uses same background style as Material Design
    /// guide and Flutter.
    ///
    /// Regardless of value used on this property, the tooltip theme created by
    /// [FlexColorScheme] does however deviate a bit from the Flutter default
    /// theme, it has slightly larger font for improved legibility on web and
    /// desktop with device pixel ratio 1.0 and also use a padding style also
    /// suitable for multiline tooltips.
    final bool tooltipsMatchBackground = false,

    /// This property has no function after 4.2.0. Prior to version 5 this
    /// property was used to activate the opinionated component sub-themes.
    /// Starting with version 5 they are now enabled by adding a default
    /// constructor `FlexSubThemesData()` to [subThemesData].
    ///
    /// Defaults to false.
    @Deprecated('This property has no function after 4.2.0. FlexColorScheme '
        'opinionated component sub-themes are added by adding a default '
        'constructor FlexSubThemesData() to subThemesData. This creates '
        'sub-themes using the FlexColorScheme opinionated defaults. You can '
        'modify the sub-themes by changing its properties.')
        final bool useSubThemes = false,

    /// Activate using FlexColorScheme opinionated component sub-themes by
    /// passing in a default `FlexSubThemesData()`.
    ///
    /// To further configure the sub-themes, change the simple flat value
    /// properties as desired in `FlexSubThemesData()`.
    ///
    /// By default [FlexThemeData.light], [FlexThemeData.dark] and
    /// [FlexColorScheme.toTheme], do as little as they need to just
    /// provide a consistent Material 2 color schemed theme. The additions they
    /// do are described in [FlexColorScheme.toTheme].
    ///
    /// The original purpose of the opinionated sub-themes was to make it easy
    /// to add themed corner radius to all Widgets that support it, and to
    /// provide a consistent look on all buttons, including [ToggleButtons].
    ///
    /// Therefore the sub themes are a convenient way to opt-in on customized
    /// corner radius on Widgets using above themes. By opting in you can set
    /// corner radius for all covered Widgets to same corner radius in one go.
    /// There are also properties to override the global default for each widget
    /// to set different rounding per widget if so desired.
    ///
    /// By default, if a `defaultRadius` is not specified, each widgets corner
    /// radius and some other styling take inspiration from the Material 3 (M3)
    /// specification https://m3.material.io/ and uses its specifications as
    /// defaults when it is possible to do so in Flutter SDK theming, within
    /// its current Material 2 (M2) design limitations.
    ///
    /// In version 5, by opting in via a default [subThemesData] you
    /// get an extensive set of widget component sub themes applied.
    /// They can be customized via the [subThemesData] property, that has
    /// quick and flat sub theme configuration values in the data class
    /// [FlexSubThemesData].
    ///
    /// These component themes are available:
    ///
    /// * [ButtonThemeData] for old deprecated buttons, via [buttonTheme].
    /// * [BottomNavigationBarThemeData] for [BottomNavigationBar] via
    ///   [bottomNavigationBar].
    /// * [BottomSheetThemeData] for [BottomSheet] via [bottomSheetTheme].
    /// * [CardTheme] for [Card] via [cardTheme].
    /// * [CheckboxThemeData] for [Checkbox] via [checkboxTheme].
    /// * [ChipThemeData] for [Chip] via [chipTheme].
    /// * [DialogTheme] for [Dialog] via [dialogTheme].
    /// * [ElevatedButtonThemeData] for [ElevatedButton] via
    ///   [elevatedButtonTheme].
    /// * [FloatingActionButtonThemeData] for [FloatingActionButton] via
    ///   [floatingActionButtonTheme].
    /// * [InputDecorationTheme] for [InputDecoration] via
    ///   [inputDecorationTheme].
    /// * [NavigationBarThemeData] for [NavigationBar] via [navigationBarTheme].
    /// * [NavigationRailThemeData] for [NavigationRail] via
    ///   [navigationRailTheme].
    /// * [OutlinedButtonThemeData] for [OutlinedButton] via
    ///   [outlinedButtonTheme].
    /// * [PopupMenuThemeData] for [PopupMenuButton] via [popupMenuTheme].
    /// * [RadioThemeData] for [Radio] via [radioTheme].
    /// * [SnackBarThemeData] for [SnackBar] via [snackBarTheme].
    /// * [SwitchThemeData] for [Switch] via [switchTheme].
    /// * [TextButtonThemeData] for [TextButton] via [textButtonTheme].
    /// * [TimePickerThemeData] for [TimePickerDialog] via [timePickerTheme].
    /// * [ToggleButtonsThemeData] for [ToggleButtons] via [toggleButtonsTheme].
    ///
    /// The custom [ButtonThemeData] still provides matching styling
    /// for the deprecated legacy buttons if they are used.
    /// Please consider phasing out the legacy buttons, as they are deprecated
    /// and will be removed from the Flutter SDK in next stable release. Their
    /// theme [ButtonThemeData] will also soon be deprecated and later removed.
    ///
    /// Defaults to null, resulting in FlexColorScheme not using any extra
    /// sub-theming in addition to those described in [FlexColorScheme.toTheme].
    final FlexSubThemesData? subThemesData,

    /// To use and activate Material 3 color system based [ColorScheme]
    /// defined via key colors for primary, secondary and tertiary colors and
    /// the [TonalPalette] generated by these key color values, pass
    /// in a [FlexKeyColors] to [keyColors].
    ///
    /// By default it is not defined (null), and a traditional manually
    /// configured color scheme will be created based on input property values
    /// or the passed in [colorScheme].
    ///
    /// If a [FlexKeyColors] instance is passed in, the key color seeding
    /// behavior depends on properties defined in the [FlexKeyColors]
    /// instance. The default constructor makes one where
    /// [FlexKyColors.useKeyColors] is true, it will automatically enable usage
    /// of key colors and from them generated color scheme.
    ///
    /// For more information on Material 3 color system and usage of key colors
    /// to generate tonal palettes and tones, see:
    /// https://m3.material.io/styles/color/the-color-system/key-colors-tones
    final FlexKeyColors? keyColors,

    /// Set to true, to use the new Material 3 error colors.
    ///
    /// If [useMaterial3ErrorColors] is false, the generated [ColorScheme]
    /// and [ThemeData] will use Material 2 default error colors or
    /// error colors as defined by the built in color schemes. Thus using same
    /// error colors as in FlexColorScheme versions before version 5.
    ///
    /// If [useMaterial3ErrorColors] is true, the resulting [ColorScheme]
    /// and [ThemeData] will use the Material 3 design guide error colors.
    ///
    /// Key color seed generated [ColorScheme]s always use the Material 3
    /// design guide error colors, or error colors from its customized
    /// [TonalPalette] generation setup.
    final bool useMaterial3ErrorColors = false,

    /// An advanced configuration class enabling complete customization of
    /// used chroma for [TonalPalette] generation for the used seed [keyColors],
    /// as well as changing which tone in the tonal palettes is used
    /// for which [ColorScheme] color.
    ///
    /// If null [FlexTones.dark] will be used, resulting in a default
    /// Material Design 3 based usage of tones and CAM16 chroma for the
    /// seed generated dark [ColorScheme].
    final FlexTones? tones,

    /// The density value for specifying the compactness of various UI
    /// components.
    ///
    /// Consider using [FlexColorScheme.comfortablePlatformDensity],
    /// it is similar to [VisualDensity.adaptivePlatformDensity], but the
    /// density for desktop and Web is less dense in order to offer a bit larger
    /// touch friendly surfaces, but not quite as large as small touch devices.
    ///
    /// This is the same property as in [ThemeData] factory, it is just
    /// passed along to it. Included for convenience to avoid a copyWith if
    /// to change it.
    ///
    /// Density, in the context of a UI, is the vertical and horizontal
    /// "compactness" of the elements in the UI. It is unit less, since it means
    /// different things to different UI elements. For buttons, it affects the
    /// spacing around the centered label of the button. For lists, it affects
    /// the distance between baselines of entries in the list.
    ///
    /// Typically, density values are integral, but any value in range may be
    /// used. The range includes values from [VisualDensity.minimumDensity]
    /// (which is -4), to [VisualDensity.maximumDensity] (which is 4),
    /// inclusive, where negative values indicate a denser, more compact, UI,
    /// and positive values indicate a less dense, more expanded, UI. If a
    /// component doesn't support the value given, it will clamp to the nearest
    /// supported value.
    ///
    /// The default for visual densities is zero for both vertical and
    /// horizontal densities, which corresponds to the default visual density of
    /// components in the Material Design specification.
    ///
    /// As a rule of thumb, a change of 1 or -1 in density corresponds to 4
    /// logical pixels. However, this is not a strict relationship since
    /// components interpret the density values appropriately for their needs.
    ///
    /// A larger value translates to a spacing increase (less dense), and a
    /// smaller value translates to a spacing decrease (more dense).
    ///
    /// Defaults to [VisualDensity.adaptivePlatformDensity].
    final VisualDensity? visualDensity,

    /// Text with a color that contrasts with the card and canvas colors.
    final TextTheme? textTheme,

    /// A text theme that contrasts with the primary color.
    final TextTheme? primaryTextTheme,

    /// Same property as in [ThemeData] factory, it is just passed along to it.
    ///
    /// Included for convenience to avoid a copyWith if it needs to be changed.
    final String? fontFamily,

    /// The platform adaptive widgets should adapt to target and mechanics too.
    ///
    /// Same property as in [ThemeData] factory. Included for convenience to
    /// avoid a copyWith change it.
    ///
    /// Defaults to the current platform, as exposed by [defaultTargetPlatform].
    /// This should be used in order to style UI elements according to platform
    /// conventions.
    ///
    /// Widgets from the material library should use this getter (via
    /// [Theme.of]) to determine the current platform for the purpose of
    /// emulating the platform behavior (e.g. scrolling or haptic effects).
    /// Widgets and render objects at lower layers that try to emulate the
    /// underlying platform platform can depend on [defaultTargetPlatform]
    /// directly, or may require that the target platform be provided as an
    /// argument. The `dart.io.Platform` object should only be used directly
    /// when it's critical to actually know the current platform, without any
    /// overrides possible, e.g. when a system API is about to be called.
    ///
    /// In a test environment, the platform returned is [TargetPlatform.android]
    /// regardless of the host platform. (Android was chosen because the tests
    /// were originally written assuming Android-like behavior, and we added
    /// platform adaptations for other platforms later). Tests can check
    /// behavior for other platforms by setting the [platform] of the [Theme]
    /// explicitly to another [TargetPlatform] value, or by setting
    /// [debugDefaultTargetPlatformOverride].
    final TargetPlatform? platform,

    /// The color and geometry [TextTheme] values use to configure [textTheme].
    ///
    /// Same property as in [ThemeData] factory. Included for convenience to
    /// avoid a copyWith change it.
    ///
    /// Included for convenience to avoid a copyWith if it needs to be changed.
    /// Default value deviates from the Flutter standard that uses the old
    /// [Typography.material2014], in favor of newer [Typography.material2018]
    /// as default typography if one is not provided.
    ///
    /// Never mix different [Typography] in light and dark theme mode. If you
    /// do, lerp between dark and light theme mode will fail due Flutter SDK
    /// not being able to handle the use case. See issue:
    /// https://github.com/flutter/flutter/issues/89947
    ///
    /// If you use a default light or
    /// dark Flutter ThemeData() and a FlexColorScheme.toTheme() ThemeData for
    /// the other mode, you must set either the default ThemeData to
    /// [Typography.material2018] OR the [FlexColorScheme.typography] to
    /// [Typography.material2014] to avoid this issue. It is not generally
    /// recommended to create your light and dark theme data with
    /// different methods. If you use FlexColorScheme, DO use it for both the
    /// light and dark theme mode.
    final Typography? typography,

    /// Apply a semi-transparent overlay color on Material surfaces to indicate
    /// elevation for dark themes.
    ///
    /// Same property as in [ThemeData] factory. Included for convenience to
    /// avoid a copyWith change it.
    ///
    /// In FlexColorScheme it defaults to true. In Flutter [ThemeData.from] it
    /// also default to true, but in [ThemeData] factory it defaults to false.
    ///
    /// Material drop shadows can be difficult to see in a dark theme, so the
    /// elevation of a surface should be portrayed with an "overlay" in addition
    /// to the shadow. As the elevation of the component increases, the
    /// overlay increases in opacity. The [applyElevationOverlayColor] turns the
    /// application of this overlay on or off for dark themes.
    ///
    /// If true and [brightness] is [Brightness.dark], a
    /// semi-transparent version of [ColorScheme.onSurface] will be
    /// applied on top of [Material] widgets that have a [ColorScheme.surface]
    /// color. The level of transparency is based on [Material.elevation] as
    /// per the Material Dark theme specification.
    ///
    /// If false the surface color will be used unmodified.
    ///
    /// Defaults to false in order to maintain backwards compatibility with
    /// apps that were built before the Material Dark theme specification
    /// was published. New apps should set this to true for any themes
    /// where [brightness] is [Brightness.dark].
    ///
    /// See also:
    ///
    ///  * [Material.elevation], which effects the level of transparency of the
    ///    overlay color.
    ///  * [ElevationOverlay.applyOverlay], which is used by [Material] to apply
    ///    the overlay color to its surface color.
    ///  * <https://material.io/design/color/dark-theme.html>, which specifies
    ///    how the overlay should be applied.
    ///
    /// Known limitations:
    ///
    /// Because of how the overlay color application is implemented in Flutter
    /// SDK, you will only get overlay color applied in dark mode when this
    /// value  is true, if the [Material] surface color being elevated is equal
    /// to [ThemeData.colorScheme] and its [ColorScheme.surface] color property.
    ///
    /// Thus when using color branded surfaces, if you want all [Material]
    /// surfaces in your theme to get an overlay color in dark mode, you must
    /// for dark themes only use background colors that are equal to the surface
    /// color. This when using [FlexColorScheme.dark] use a [FlexSurfaceMode]
    /// that starts with `equal`. That said, if using heavy color branding,
    /// some surfaces may not need any overlay color, so the
    /// lack of it might not be an issue with other modes in such themes.
    /// For more information about this limitation see Flutter SDK issue:
    /// https://github.com/flutter/flutter/issues/90353
    final bool applyElevationOverlayColor = true,

    /// A temporary flag used to opt-in to new SDK Material 3 features.
    ///
    /// Flutter SDK 3.0.5 [useMaterial3] documentation:
    /// -----------------------------------------------
    /// If true, then components that have been migrated to Material 3 will
    /// use new colors, typography and other features of Material 3.
    /// If false, they will use the Material 2 look and feel.
    ///
    /// If a [ThemeData] is constructed with [useMaterial3] set to true, then
    /// some properties will get special defaults. However, just copying a
    /// [ThemeData] with [useMaterial3] set to true will not change any of
    /// these properties in the
    /// resulting [ThemeData]. These properties are:
    /// <style>table,td,th { border-collapse: collapse; padding: 0.45em; }
    /// td { border: 1px solid }</style>
    ///
    /// | Property        | Material 3 default           | Fallback default  |
    /// | :-------------- | :--------------------------- | :---------------- |
    /// | [typography] | [Typography.material2021] | [Typography.material2014] |
    /// | [splashFactory] | [InkSparkle]* or [InkRipple] | [InkSplash]       |
    ///
    /// \* if and only if the target platform is Android and the app is not
    /// running on the web, otherwise it will fallback to [InkRipple].
    ///
    /// During the migration to Material 3, turning this on may yield
    /// inconsistent look and feel in your app. Some components will be migrated
    /// before others and typography changes will be coming in stages.
    ///
    /// [useMaterial3] defaults to false. After all the migrated components
    /// have landed on stable, we will change this to be true by default. After
    /// that change has landed on stable, we will deprecate this flag and remove
    /// all uses of it. Everything will use the Material 3 look and feel at
    /// that point.
    ///
    /// Components that have been migrated to Material 3 are:
    ///
    ///   * [AlertDialog]
    ///   * [AppBar]
    ///   * [Card]
    ///   * [Dialog]
    ///   * [ElevatedButton]
    ///   * [FloatingActionButton]
    ///   * [Material]
    ///   * [NavigationBar]
    ///   * [NavigationRail]
    ///   * [OutlinedButton]
    ///   * [StretchingOverscrollIndicator], replacing the
    ///     [GlowingOverscrollIndicator]
    ///   * [TextButton]
    ///
    /// See also:
    ///
    ///   * [Material Design 3](https://m3.material.io).
    ///
    /// While the migration of Flutter SDK to the Material 3 design spec is
    /// in progress, setting [useSubThemes] in [FlexColorScheme] to true,
    /// will also produce widget sub-themes using current Flutter Material 2
    /// theming limitations. By default these opinionated sub-themes also
    /// implement the Material 3 design and look when it is possible within
    /// current SDK limits. During SDK transition to full M3 support, keeping
    /// useMaterial3 false and just using the FlexColorScheme sub-theming, may
    /// be preferred since it has fewer transitional issues.
    final bool useMaterial3 = false,

    /// Arbitrary additions to this theme.
    ///
    /// This is the same property as [extensions] in ThemeData, it is provided
    /// as a convenience pass-through to ThemeData.
    ///
    /// To define extensions, pass an [Iterable] containing one or more
    /// [ThemeExtension] subclasses to [ThemeData.new] or [copyWith].
    ///
    /// To obtain an extension, use ThemeData.of(context).extension.
    final Iterable<ThemeExtension<dynamic>>? extensions,
  }) {
    // DARK: Check valid inputs
    assert(usedColors >= 1 && usedColors <= 6, 'usedColors must be 1 to 6.');
    assert(appBarOpacity >= 0 && appBarOpacity <= 1,
        'appBarOpacity must be 0 to 1');
    assert(
      blendLevel >= 0 && blendLevel <= 40,
      'Only blend levels from 0 to 40 are allowed. Very high alpha values may '
      'not produce results that are visually very appealing or useful.',
    );
    assert(appBarElevation >= 0.0, 'AppBar elevation must be >= 0.');
    assert(bottomAppBarElevation == null || bottomAppBarElevation >= 0.0,
        'Bottom AppBar elevation must be null or must be >= 0.');
    // If bottomAppBarElevation is null, fallback to appBarElevation.
    final double effectiveBottomAppBarElevation =
        bottomAppBarElevation ?? appBarElevation;
    // Use color seeding based on passed in keyColors or make one where
    // it is not used, if one was not defined, since we want that as default
    // behavior to match past default behavior.
    final FlexKeyColors seed =
        keyColors ?? const FlexKeyColors(useKeyColors: false);
    // Fallback value for scheme is default material scheme.
    final FlexScheme flexScheme = scheme ?? FlexScheme.material;
    // If colors was null, we used the scheme based value.
    final FlexSchemeColor flexColors =
        colors ?? FlexColor.schemesWithCustom[flexScheme]!.dark;

    // If the passed in property values are not null, or there was a colorScheme
    // provided, we will override the colors properties with them. Doing it here
    // gets also correct effective and swap behavior on directly passed in
    // property values or colorScheme based colors too.
    final FlexSchemeColor withPassedColors = flexColors.copyWith(
      primary: primary ?? colorScheme?.primary,
      // Use primaryVariant also as potential passed in override for
      // container, for backwards behavior compatibility.
      // TODO(rydmike): Remove backwards compatibility behavior in v6.0.0.
      primaryContainer:
          primaryContainer ?? primaryVariant ?? colorScheme?.primaryContainer,
      secondary: secondary ?? colorScheme?.secondary,
      // Use old secondaryVariant as potential passed in override for
      // container, for backwards behavior compatibility.
      secondaryContainer: secondaryContainer ??
          secondaryVariant ??
          colorScheme?.secondaryContainer,
      tertiary: tertiary ?? colorScheme?.tertiary,
      tertiaryContainer: tertiaryContainer ?? colorScheme?.tertiaryContainer,
      error: error ?? colorScheme?.error,
      errorContainer: colorScheme?.errorContainer,
    );
    // First cut of effective FlexSchemeColor depends on colors, usedColors
    // and swap. When we use Brightness.dark, we also guarantee that we have
    // colors on effectiveColors.error and errorContainer, they are guaranteed
    // to no longer be null after this call.
    FlexSchemeColor effectiveColors = FlexSchemeColor.effective(
      withPassedColors,
      usedColors,
      swapColors: swapColors,
      brightness: Brightness.dark,
    );
    // ColorScheme to hold our seeded scheme colors, it will be kept as null
    // if we do not use M3 key based seeded tonal palette ColorScheme.
    ColorScheme? seedScheme;
    // If keyColor seeds is active, apply seeded colors to effective colors.
    if (seed.useKeyColors) {
      // Build effective input key seed colors as we built the normal colors.
      // We will need the scheme enum light color as input, for dark tonal when
      // we use seed with built in schemes in dark mode.
      final FlexSchemeColor flexKeyColors =
          colors ?? FlexColor.schemesWithCustom[flexScheme]!.light;
      // Get effective light color with same rules as the dark colors.
      final FlexSchemeColor withPassedColors = flexKeyColors.copyWith(
        primary: primary ?? colorScheme?.primary,
        primaryContainer:
            primaryContainer ?? primaryVariant ?? colorScheme?.primaryContainer,
        secondary: secondary ?? colorScheme?.secondary,
        secondaryContainer: secondaryContainer ??
            secondaryVariant ??
            colorScheme?.secondaryContainer,
        tertiary: tertiary ?? colorScheme?.tertiary,
        tertiaryContainer: tertiaryContainer ?? colorScheme?.tertiaryContainer,
      );
      final FlexSchemeColor effectiveKeyColors = FlexSchemeColor.effective(
        withPassedColors,
        usedColors,
        swapColors: swapColors,
        brightness: Brightness.dark,
      );
      // Create a ColorScheme from active and effective seed key colors.
      seedScheme = _Scheme.fromSeeds(
        brightness: Brightness.dark,
        primaryKey: effectiveKeyColors.primary,
        // If use secondary seed, use it with fromSeeds, otherwise undefined.
        secondaryKey: seed.useSecondary ? effectiveKeyColors.secondary : null,
        // If use tertiary seed, use it with fromSeeds, otherwise undefined.
        tertiaryKey: seed.useTertiary ? effectiveKeyColors.tertiary : null,
        // Use provided tones configuration or the default one, which uses
        // defaults that can produce same results as Flutter SDK,
        // ColorScheme.fromSeed(color), when only primary color is used as key.
        tones: tones ?? const FlexTones.dark(),
        surfaceTint: surfaceTint,
      );
      // Update effective main colors to seed colors, keeping configured
      // effective main color values when so defined. The main colors to keep
      // are the ones from the effective normal dark scheme, not the key colors.
      effectiveColors = FlexSchemeColor(
        primary:
            seed.keepPrimary ? effectiveColors.primary : seedScheme.primary,
        primaryContainer: seed.keepPrimaryContainer
            ? effectiveColors.primaryContainer
            : seedScheme.primaryContainer,
        secondary: seed.keepSecondary
            ? effectiveColors.secondary
            : seedScheme.secondary,
        secondaryContainer: seed.keepSecondaryContainer
            ? effectiveColors.secondaryContainer
            : seedScheme.secondaryContainer,
        tertiary:
            seed.keepTertiary ? effectiveColors.tertiary : seedScheme.tertiary,
        tertiaryContainer: seed.keepTertiaryContainer
            ? effectiveColors.tertiaryContainer
            : seedScheme.tertiaryContainer,
        appBarColor: effectiveColors.appBarColor,
        error: seedScheme.error,
        errorContainer: seedScheme.errorContainer,
      );
    }
    // Get effective surfaceTint color, also used as blend color for surfaces.
    final Color blendColor =
        surfaceTint ?? colorScheme?.surfaceTint ?? effectiveColors.primary;
    // Compute surface blends, they may also be added on seeded surfaces.
    final FlexSchemeSurfaceColors surfaceSchemeColors =
        FlexSchemeSurfaceColors.blend(
      brightness: Brightness.dark,
      surfaceMode: surfaceMode ?? FlexSurfaceMode.highScaffoldLowSurfaces,
      blendLevel: blendLevel,
      surfaceVariantBlendDivide: seed.useKeyColors ? 2 : 1,
      schemeColors: effectiveColors,
      blendColors: FlexSchemeSurfaceColors(
        surface: blendColor,
        surfaceVariant: blendColor,
        inverseSurface: blendColor,
        dialogBackground: blendColor,
        background: blendColor,
        scaffoldBackground: blendColor,
      ),
      surfaceColors: seed.useKeyColors
          // Using seed colors, starting surfaces are given by generated scheme.
          ? FlexSchemeSurfaceColors(
              surface: seedScheme!.surface,
              surfaceVariant: seedScheme.surfaceVariant,
              inverseSurface: seedScheme.inverseSurface,
              dialogBackground: seedScheme.surface,
              background: seedScheme.background,
              scaffoldBackground: seedScheme.background,
            )
          // Default surfaces are used as starting point for blended ones.
          : null,
    );
    // We on purpose shadow deprecated this.useSubThemesData that has
    // been deprecated, and set it it true if a none null subThemesData was
    // provided.
    final bool useSubThemes = subThemesData != null;
    // Use passed in sub-theme config data, or a default one, if none given.
    final FlexSubThemesData subTheme =
        subThemesData ?? const FlexSubThemesData();
    // Effective blend level for the onColors.
    int onBlendLevel = useSubThemes ? subTheme.blendOnLevel : 0;
    assert(
        onBlendLevel >= 0 && onBlendLevel <= 40,
        'Only onBlendLevel:s from 0 to 40 '
        'are allowed. Very high alpha blend levels may not produce results '
        'that are visually very appealing or useful.');
    // If above happens in none debug mode, use 0, no blends.
    if (onBlendLevel < 0 || onBlendLevel > 40) onBlendLevel = 0;

    // Get alpha blend values for used mode, on blend level and brightness,
    // used for onContainers and onSurface and onBackground.
    final _AlphaValues alphaOnValue = useSubThemes
        ? _AlphaValues.getAlphas(
            surfaceMode ?? FlexSurfaceMode.highScaffoldLowSurfaces,
            onBlendLevel)
        : const _AlphaValues();
    // Get alpha blend values for used mode, on blend level and brightness,
    // used for onPrimary, onSecondary, onTertiary and onError.
    final _AlphaValues alphaOnMain = useSubThemes && subTheme.blendOnColors
        ? _AlphaValues.getAlphas(
            surfaceMode ?? FlexSurfaceMode.highScaffoldLowSurfaces,
            onBlendLevel)
        : const _AlphaValues();
    // Determine the input surface and background colors.
    final Color inputSurface = surface ?? surfaceSchemeColors.surface;
    final Color inputBackground = background ?? surfaceSchemeColors.background;

    final FlexSchemeOnColors onColors = FlexSchemeOnColors.from(
      primary: effectiveColors.primary,
      primaryContainer: effectiveColors.primaryContainer,
      secondary: effectiveColors.secondary,
      secondaryContainer: effectiveColors.secondaryContainer,
      tertiary: effectiveColors.tertiary,
      tertiaryContainer: effectiveColors.tertiaryContainer,
      surface: inputSurface,
      surfaceVariant: surfaceSchemeColors.surfaceVariant,
      inverseSurface: surfaceSchemeColors.inverseSurface,
      background: inputBackground,
      error: effectiveColors.error!,
      errorContainer: effectiveColors.errorContainer,
      onPrimary: onPrimary ??
          (seed.useKeyColors && seed.keepPrimary
              ? null
              : seedScheme?.onPrimary) ??
          colorScheme?.onPrimary,
      onPrimaryContainer: onPrimaryContainer ??
          (seed.useKeyColors && seed.keepPrimaryContainer
              ? null
              : seedScheme?.onPrimaryContainer) ??
          colorScheme?.onPrimaryContainer,
      onSecondary: onSecondary ??
          (seed.useKeyColors && seed.keepSecondary
              ? null
              : seedScheme?.onSecondary) ??
          colorScheme?.onSecondary,
      onSecondaryContainer: onSecondaryContainer ??
          (seed.useKeyColors && seed.keepSecondaryContainer
              ? null
              : seedScheme?.onSecondaryContainer) ??
          colorScheme?.onSecondaryContainer,
      onTertiary: onTertiary ??
          (seed.useKeyColors && seed.keepTertiary
              ? null
              : seedScheme?.onTertiary) ??
          colorScheme?.onTertiary,
      onTertiaryContainer: onTertiaryContainer ??
          (seed.useKeyColors && seed.keepTertiaryContainer
              ? null
              : seedScheme?.onTertiaryContainer) ??
          colorScheme?.onTertiaryContainer,
      onSurface: onSurface ?? seedScheme?.onSurface ?? colorScheme?.onSurface,
      onSurfaceVariant:
          seedScheme?.onSurfaceVariant ?? colorScheme?.onSurfaceVariant,
      onInverseSurface:
          seedScheme?.onInverseSurface ?? colorScheme?.onInverseSurface,
      onBackground:
          onBackground ?? seedScheme?.onBackground ?? colorScheme?.onBackground,
      onError: onError ?? seedScheme?.onError ?? colorScheme?.onError,
      onErrorContainer: seedScheme?.onError ?? colorScheme?.onErrorContainer,
      primaryAlpha: alphaOnMain.primaryAlpha,
      primaryContainerAlpha: alphaOnValue.primaryContainerAlpha,
      secondaryAlpha: alphaOnMain.secondaryAlpha,
      secondaryContainerAlpha: alphaOnValue.secondaryContainerAlpha,
      tertiaryAlpha: alphaOnMain.tertiaryAlpha,
      tertiaryContainerAlpha: alphaOnValue.tertiaryContainerAlpha,
      surfaceAlpha: alphaOnValue.surfaceAlpha,
      surfaceVariantAlpha: alphaOnValue.surfaceVariantAlpha,
      inverseSurfaceAlpha: alphaOnValue.inverseSurfaceAlpha,
      backgroundAlpha: alphaOnValue.backgroundAlpha,
      errorAlpha: alphaOnMain.errorAlpha,
      errorContainerAlpha: alphaOnValue.errorContainerAlpha,
    );
    // Determine effective surface color.
    // Surface is used e.g. by Card and bottom appbar.
    // If true black, we make a darker than normal surface. If not
    // true black, we use provided surface color, or computed one.
    final Color effectiveSurfaceColor =
        darkIsTrueBlack ? inputSurface.darken(5) : inputSurface;
    final Color effectiveSurfaceVariantColor = darkIsTrueBlack
        ? surfaceSchemeColors.surfaceVariant.darken(5)
        : surfaceSchemeColors.surfaceVariant;
    final Color effectiveInverseSurfaceColor = darkIsTrueBlack
        ? surfaceSchemeColors.inverseSurface.lighten(5)
        : surfaceSchemeColors.inverseSurface;
    // Determine effective background color.
    // Used e.g. by drawer, nav rail, side menu and bottom bar.
    // If true black, we use darker then normal background. If not true black,
    // we use provided background color, or computed one.
    final Color effectiveBackgroundColor =
        darkIsTrueBlack ? inputBackground.darken(5) : inputBackground;
    // Determine effective dialog background color.
    // If true black, we use darker than normal. If not true black,
    // we use dialog provided background color, or computed one.
    // The provided dialog background color overrides factory surface behavior,
    // but is impacted by true black mode for a darker effect.
    final Color effectiveDialogBackground = darkIsTrueBlack
        ? dialogBackground?.darken(5) ??
            surfaceSchemeColors.dialogBackground.darken(5)
        : dialogBackground ?? surfaceSchemeColors.dialogBackground;
    // Compute the effective ColorScheme based on all selection options.
    final ColorScheme effectiveColorScheme = seedScheme?.copyWith(
          // We made a seeded color scheme, we use it as given but set
          // override values for props we have not handled via FCS direct
          // props further below. We don't adjust onColors for
          // surfaceVariant and inverseSurface on purpose.
          surfaceVariant: effectiveSurfaceVariantColor,
          inverseSurface: effectiveInverseSurfaceColor,
          surfaceTint: surfaceTint,
        ) ??
        // We had a colorScheme passed in, we use as passed in, but set
        // override values for props we have not handled via FCS direct
        // props further below.
        colorScheme?.copyWith(
          surfaceVariant: effectiveSurfaceVariantColor,
          onSurfaceVariant: onColors.onSurfaceVariant,
          inverseSurface: effectiveInverseSurfaceColor,
          onInverseSurface: onColors.onInverseSurface,
          surfaceTint: surfaceTint,
        ) ??
        // In order to avoid using a ColorScheme.dark that sets
        // some opinionated defaults on deprecated members that we do not
        // want, we make a full one matching the target. Values that
        // exist as direct properties in FlexColorScheme, will actually
        // be used via them further below, but we need this ColorScheme
        // to provide the properties we are not handling via FCS
        // constructor. An alternative would be to add missing ColorScheme
        // properties to FlexColorScheme as direct override properties,
        // might do so later.
        ColorScheme(
          brightness: Brightness.dark,
          primary: effectiveColors.primary,
          onPrimary: onColors.onPrimary,
          primaryContainer: effectiveColors.primaryContainer,
          onPrimaryContainer: onColors.onPrimaryContainer,
          secondary: effectiveColors.secondary,
          onSecondary: onColors.onSecondary,
          secondaryContainer: effectiveColors.secondaryContainer,
          onSecondaryContainer: onColors.onSecondaryContainer,
          tertiary: effectiveColors.tertiary,
          onTertiary: onColors.onTertiary,
          tertiaryContainer: effectiveColors.tertiaryContainer,
          onTertiaryContainer: onColors.onTertiaryContainer,
          error: useMaterial3ErrorColors && !seed.useKeyColors
              ? FlexColor.material3DarkError
              : effectiveColors.error ?? FlexColor.materialDarkError,
          onError: useMaterial3ErrorColors && !seed.useKeyColors
              ? FlexColor.material3DarkOnError
              : onColors.onError,
          errorContainer: useMaterial3ErrorColors && !seed.useKeyColors
              ? FlexColor.material3DarkErrorContainer
              : effectiveColors.errorContainer!,
          onErrorContainer: useMaterial3ErrorColors && !seed.useKeyColors
              ? FlexColor.material3DarkOnErrorContainer
              : onColors.onErrorContainer,
          background: effectiveBackgroundColor,
          onBackground: onColors.onBackground,
          surface: effectiveSurfaceColor,
          onSurface: onColors.onSurface,
          surfaceVariant: effectiveSurfaceVariantColor,
          onSurfaceVariant: onColors.onSurfaceVariant,
          inverseSurface: effectiveInverseSurfaceColor,
          onInverseSurface: onColors.onInverseSurface,
          inversePrimary: _inversePrimary(
              Brightness.dark, effectiveColors.primary, effectiveSurfaceColor),
          shadow: Colors.black,
          outline: _outlineColor(Brightness.dark, onColors.onBackground),
          surfaceTint: surfaceTint ?? effectiveColors.primary,
        );

    // Determine the effective AppBar color:
    // - First priority, passed in color value.
    Color? effectiveAppBarColor = appBarBackground;
    // - Second priority, sub-theme based scheme color.
    effectiveAppBarColor ??=
        useSubThemes && subTheme.appBarBackgroundSchemeColor != null
            ? FlexSubThemes.schemeColor(
                subTheme.appBarBackgroundSchemeColor!, effectiveColorScheme)
            : null;
    // Third priority [appBarStyle] based.
    if (effectiveAppBarColor == null) {
      switch (appBarStyle) {
        case FlexAppBarStyle.primary:
          effectiveAppBarColor = effectiveColors.primary;
          break;
        case FlexAppBarStyle.material:
          effectiveAppBarColor = FlexColor.materialDarkSurface;
          break;
        case FlexAppBarStyle.background:
          effectiveAppBarColor = effectiveBackgroundColor;
          break;
        case FlexAppBarStyle.surface:
          effectiveAppBarColor = effectiveSurfaceColor;
          break;
        case FlexAppBarStyle.custom:
          effectiveAppBarColor =
              effectiveColors.appBarColor ?? effectiveColors.primary;
          break;
      }
    }
    // Apply specified opacity on on the resulting color.
    effectiveAppBarColor = effectiveAppBarColor.withOpacity(appBarOpacity);

    return FlexColorScheme(
      colorScheme: effectiveColorScheme,
      // This is the dark theme factory so we always set brightness to dark.
      brightness: Brightness.dark,
      // Primary colors for the application
      primary: effectiveColors.primary,
      primaryContainer: effectiveColors.primaryContainer,
      // The secondary colors for the application.
      secondary: effectiveColors.secondary,
      secondaryContainer: effectiveColors.secondaryContainer,
      // Tertiary colors for the application.
      tertiary: effectiveColors.tertiary,
      tertiaryContainer: effectiveColors.tertiaryContainer,
      // Surface is used e.g. by Card and bottom appbar and in this
      // implementation also by dialogs.
      surface: effectiveSurfaceColor,
      // Used e.g. by drawer, nav rail, side menu and bottom bar.
      background: effectiveBackgroundColor,
      // If darkIsTrueBlack is set, we use black as default scaffold background,
      // otherwise provided value or if null effective scheme background.
      scaffoldBackground: scaffoldBackground ??
          (darkIsTrueBlack
              ? Colors.black
              : surfaceSchemeColors.scaffoldBackground),
      // Color of dialog background elements, a passed in dialogBackground
      // color will override the factory style, if provided.
      dialogBackground: effectiveDialogBackground,
      // Set app bar background to effective background color, but a passed
      // in appBarBackground will override it if provided.
      appBarBackground: effectiveAppBarColor,
      // Effective error color and null fallback.
      error: useMaterial3ErrorColors && !seed.useKeyColors
          ? FlexColor.material3DarkError
          : effectiveColors.error ?? FlexColor.materialDarkError,
      onPrimary: onColors.onPrimary,
      onPrimaryContainer: onColors.onPrimaryContainer,
      onSecondary: onColors.onSecondary,
      onSecondaryContainer: onColors.onSecondaryContainer,
      onTertiary: onColors.onTertiary,
      onTertiaryContainer: onColors.onTertiaryContainer,
      onSurface: onColors.onSurface,
      onBackground: onColors.onBackground,
      onError: useMaterial3ErrorColors && !seed.useKeyColors
          ? FlexColor.material3DarkOnError
          : onColors.onError,
      surfaceTint: surfaceTint,
      tabBarStyle: tabBarStyle,
      appBarElevation: appBarElevation,
      bottomAppBarElevation: effectiveBottomAppBarElevation,
      tooltipsMatchBackground: tooltipsMatchBackground,
      transparentStatusBar: transparentStatusBar,
      visualDensity: visualDensity,
      textTheme: textTheme,
      primaryTextTheme: primaryTextTheme,
      fontFamily: fontFamily,
      platform: platform,
      typography: typography,
      applyElevationOverlayColor: applyElevationOverlayColor,
      subThemesData: subThemesData,
      useMaterial3: useMaterial3,
      extensions: extensions,
    );
  }

  //****************************************************************************
  //
  // STATIC HELPER FUNCTIONS AND CONSTANTS
  //
  //  * m3TextTheme - A static const M3 like text theme, font size wise.
  //  * comfortablePlatformDensity
  //  * themedSystemNavigationBar
  //  * createPrimarySwatch
  //
  //****************************************************************************

  /// DEPRECATED: A Material 3 (M3) like and inspired [TextTheme].
  ///
  /// This property was deprecated in version 6.0.0. With release of Flutter
  /// 3.0.0, it is no longer needed in FlexColorScheme. It will be removed in
  /// FCS version 7.0.0.
  ///
  /// This text theme was used in versions before FCS 6.0.0 when the sub-themes
  /// text theme opt-in toggle was used, to make a TextTheme that matched the
  /// Material 3 text theme specification before it existed in Flutter stable
  /// channel. After release of Flutter 3.0.0, where this landed:
  /// https://github.com/flutter/flutter/pull/97829. The custom FCS M3 TextTheme
  /// is no longer need or used. Instead FlexColorScheme uses the in Flutter SDK
  /// built-in M3 TextTheme Typography when setting
  /// [FlexColorScheme.useMaterial3] to true **or**
  /// property [FlexSubThemesData.useTextTheme] in a
  /// [FlexSubThemesData] passed to [FlexColorScheme.subThemesData] is true.
  ///
  /// In a FlexSubThemesData() default constructor the
  /// [FlexSubThemesData.useTextTheme] property defaults to true, as its
  /// opinionated choice.
  ///
  /// The geometry of the used M3 styles were made based on this:
  /// https://github.com/flutter/flutter/issues/89853
  ///
  /// M3 has 2 more text styles than M3, those are [headlineLarge] and
  /// [labelMedium]. Starting from Flutter stable 2.10.0 the new TextStyle names
  /// in M3 are included in Flutter and can be used. Same TextTheme can however
  /// not mix the two name spaces. When creating a [TextTheme] with either
  /// M2 or M3 [TextStyle] names, the names are automatically mapped by Flutter
  /// to the other names.
  ///
  /// The [m3TextTheme] creates a TextTheme using the new M3 [TextStyle] names
  /// and assigns the EnglishLike2021 new Typography (Geometry) to it.
  /// This M3 based Typography and geometry is not available in Flutter
  /// stable (2.10.x). These new M3 text style names are mapped to old M2 names
  /// automatically by Flutter SDK from version 2.10.0.
  @Deprecated('The m3TextTheme was deprecated in version 6.0.0. With release '
      'of Flutter 3.0.0, it is no longer needed. It will be removed in version '
      'FlexColorScheme version 7.0.0.')
  static const TextTheme m3TextTheme = TextTheme(
    // M3 displayLarge, M2 headline1. Material2018 Typography: 96, w300, -1.5
    displayLarge: TextStyle(
        debugLabel: 'englishLike displayLarge 2021',
        fontSize: 57.0,
        fontWeight: FontWeight.w400,
        letterSpacing: -0.25,
        height: 1.12,
        textBaseline: TextBaseline.alphabetic,
        leadingDistribution: TextLeadingDistribution.even),
    // M3 displayMedium, M2 headline2. In 2018 Typography: 60, w300, -0.5
    displayMedium: TextStyle(
        debugLabel: 'englishLike displayMedium 2021',
        fontSize: 45.0,
        fontWeight: FontWeight.w400,
        letterSpacing: 0.0,
        height: 1.16,
        textBaseline: TextBaseline.alphabetic,
        leadingDistribution: TextLeadingDistribution.even),
    // M3 displaySmall, M2 headline2. In Material2018 Typography: 48, w400, 0
    displaySmall: TextStyle(
        debugLabel: 'englishLike displaySmall 2021',
        fontSize: 36.0,
        fontWeight: FontWeight.w400,
        letterSpacing: 0.0,
        height: 1.22,
        textBaseline: TextBaseline.alphabetic,
        leadingDistribution: TextLeadingDistribution.even),
    // M3 headlineLarge, M2 <none>. In Material2018 no equivalent exists.
    headlineLarge: TextStyle(
        debugLabel: 'englishLike headlineLarge 2021',
        fontSize: 32.0,
        fontWeight: FontWeight.w400,
        letterSpacing: 0.0,
        height: 1.25,
        textBaseline: TextBaseline.alphabetic,
        leadingDistribution: TextLeadingDistribution.even),
    // M3 headlineMedium, M2 headline4. In 2018 Typography: 34, w400, 0.25
    headlineMedium: TextStyle(
        debugLabel: 'englishLike headlineMedium 2021',
        fontSize: 28.0,
        fontWeight: FontWeight.w400,
        letterSpacing: 0.0,
        height: 1.29,
        textBaseline: TextBaseline.alphabetic,
        leadingDistribution: TextLeadingDistribution.even),
    // M3 headlineSmall, M2 headline5. In Material2018 Typography: 24, w400, 0
    headlineSmall: TextStyle(
        debugLabel: 'englishLike headlineSmall 2021',
        fontSize: 24.0,
        fontWeight: FontWeight.w400,
        letterSpacing: 0.0,
        height: 1.33,
        textBaseline: TextBaseline.alphabetic,
        leadingDistribution: TextLeadingDistribution.even),
    // M3 titleLarge, M2 headline6. In Material2018 Typography: 20, w500, 0.15
    titleLarge: TextStyle(
        debugLabel: 'englishLike titleLarge 2021',
        fontSize: 22.0,
        fontWeight: FontWeight.w400,
        letterSpacing: 0.0,
        height: 1.27,
        textBaseline: TextBaseline.alphabetic,
        leadingDistribution: TextLeadingDistribution.even),
    // M3 titleMedium, M2 subtitle1. In Material2018 Typography: 16, w400, 0.15
    titleMedium: TextStyle(
        debugLabel: 'englishLike titleMedium 2021',
        fontSize: 16.0,
        fontWeight: FontWeight.w500,
        letterSpacing: 0.15,
        height: 1.50,
        textBaseline: TextBaseline.alphabetic,
        leadingDistribution: TextLeadingDistribution.even),
    // M3 titleSmall, M2 subtitle2. In Material2018 Typography: 14, w500, 0.1
    titleSmall: TextStyle(
        debugLabel: 'englishLike titleSmall 2021',
        fontSize: 14.0,
        fontWeight: FontWeight.w500,
        letterSpacing: 0.1,
        height: 1.43,
        textBaseline: TextBaseline.alphabetic,
        leadingDistribution: TextLeadingDistribution.even),
    // M3 labelLarge, M2 button. In Material2018 Typography: 14, w500, 1.25
    labelLarge: TextStyle(
        debugLabel: 'englishLike labelLarge 2021',
        fontSize: 14.0,
        fontWeight: FontWeight.w500,
        letterSpacing: 0.1,
        height: 1.43,
        textBaseline: TextBaseline.alphabetic,
        leadingDistribution: TextLeadingDistribution.even),
    // M3 labelMedium, M2 <none>. In Material2018 no equivalent exists.
    labelMedium: TextStyle(
        debugLabel: 'englishLike labelMedium 2021',
        fontSize: 12.0,
        fontWeight: FontWeight.w500,
        letterSpacing: 0.5,
        height: 1.33,
        textBaseline: TextBaseline.alphabetic,
        leadingDistribution: TextLeadingDistribution.even),
    // M3 labelSmall, M2 overline. In Material2018 Typography: 10, w400, 1.5
    labelSmall: TextStyle(
        debugLabel: 'englishLike labelSmall 2021',
        fontSize: 11.0,
        fontWeight: FontWeight.w500,
        letterSpacing: 0.5,
        height: 1.45,
        textBaseline: TextBaseline.alphabetic,
        leadingDistribution: TextLeadingDistribution.even),
    // M3 bodyLarge, M2 bodyText1. In Material2018 Typography: 16, w400, 0.5
    bodyLarge: TextStyle(
        debugLabel: 'englishLike bodyLarge 2021',
        fontSize: 16.0,
        fontWeight: FontWeight.w400,
        // M3 Guide said 0.15: https://m3.material.io/styles/typography/tokens
        // Table here said 0.5: https://github.com/flutter/flutter/issues/89853
        // Used Guide value first, turned out M3 WEB spec was wrong based on:
        // https://github.com/flutter/flutter/issues/102121
        // Changed to 0.5 in fix version 5.0.1
        letterSpacing: 0.5,
        height: 1.50,
        textBaseline: TextBaseline.alphabetic,
        leadingDistribution: TextLeadingDistribution.even),
    // M3 bodyMedium, M2 bodyText2. In Material2018 Typography: 14, w400, 0.25
    bodyMedium: TextStyle(
        debugLabel: 'englishLike bodyMedium 2021',
        fontSize: 14.0,
        fontWeight: FontWeight.w400,
        letterSpacing: 0.25,
        height: 1.43,
        textBaseline: TextBaseline.alphabetic,
        leadingDistribution: TextLeadingDistribution.even),
    // M3 bodySmall, M2 caption. In Material2018 Typography: 12, w400, 0.4
    bodySmall: TextStyle(
        debugLabel: 'englishLike bodySmall 2021',
        fontSize: 12.0,
        fontWeight: FontWeight.w400,
        letterSpacing: 0.4,
        height: 1.33,
        textBaseline: TextBaseline.alphabetic,
        leadingDistribution: TextLeadingDistribution.even),
  );

  /// Returns a [VisualDensity] that is [defaultTargetPlatform] adaptive to
  /// [VisualDensity.comfortable] instead of to [VisualDensity.compact].
  ///
  /// For desktop platforms, this returns [VisualDensity.comfortable], and
  /// for other platforms, it returns the default [VisualDensity.standard].
  ///
  /// This is a variant of the [VisualDensity.adaptivePlatformDensity] that
  /// returns [VisualDensity.compact] for desktop platforms.
  ///
  /// The comfortable visual density is useful on desktop and desktop web
  /// laptops that have touch screens, as it keeps touch targets a bit larger
  /// than when using compact.
  static VisualDensity get comfortablePlatformDensity {
    switch (defaultTargetPlatform) {
      case TargetPlatform.android:
      case TargetPlatform.iOS:
      case TargetPlatform.fuchsia:
        break;
      case TargetPlatform.linux:
      case TargetPlatform.macOS:
      case TargetPlatform.windows:
        return VisualDensity.comfortable;
    }
    return VisualDensity.standard;
  }

  /// Returns a [SystemUiOverlayStyle] that by default has a system navigation
  /// bar style that matches the current theme.
  ///
  /// For its default behavior it requires a build context with access to the
  /// inherited theme. This static function is a convenience wrapper for making
  /// a [SystemUiOverlayStyle] that follows current theme. For very customized
  /// styles consider using [SystemUiOverlayStyle] directly.
  ///
  /// By default when calling [themedSystemNavigationBar] with context, it
  /// creates a [SystemUiOverlayStyle] where the system navigator bar uses
  /// current theme's ´colorScheme.background´ as its background color and
  /// icon colors that match this background, without any divider.
  ///
  /// The background color can be modified with [systemNavBarStyle] that
  /// can use: system, surface, background, scaffoldBackground or transparent
  /// options as background color options. It defaults to background.
  /// See [FlexSystemNavBarStyle] for more info.
  ///
  /// In standard Flutter themes, the surface, background, scaffoldBackground
  /// and in light theme, even system are all the same color. For such themes
  /// this convenience property does not make so much sense. However, if you use
  /// FlexColorScheme and its primary color surface branding, these colors are
  /// not the same. This then offers a convenient way to switch the
  /// background color of your system navigation bar in a way that matches
  /// your theme's surface branded background color and to choose which one
  /// to use.
  ///
  /// The always sets `systemNavigationBarContrastEnforced: false` to try to
  /// avoid the system scrim on Android version where it is supported. This
  /// is done because the selected background color is the scrim itself when
  /// used with the opacity parameter and we never want an extra scrim. If we
  /// set opacity very low and loose contrast due to that, it is because it is
  /// our intent.
  ///
  /// An optional divider on the navigation bar is also available.
  /// Based on Flutter SDK docs, the divider on the navigation bar, is on
  /// respected on Android P (= Pie = SDK API 28 = Android 9) or higher. But
  /// based on our findings it does not work until Android 10 (SDK29 or
  /// higher. The divider can be turned on by setting [useDivider] to true.
  /// This produces a divider on top of the system navigation bar that in
  /// light theme mode uses color 0xFF2C2C2C and in dark mode and 0xFFDDDDDD.
  ///
  /// You can modify the default color of the divider with the optional
  /// [systemNavigationBarDividerColor]. The call to set and use the divider
  /// color is only made once a none null or true value has been given to
  /// [useDivider].
  /// Android SDK < 29 does not respect provided alpha value on the color of
  /// the divider color, and calling it with null again will not remove it.
  ///
  /// Be aware that once you have enabled the divider by setting it to true that
  /// there is no convenient way to get rid of it. You can set the value
  /// to false, but that will just make the divider same color as your current
  /// nav bar background color to make it invisible, it is still there, but
  /// still this implementation trick works well.
  ///
  /// Important: The divider is actually a layer behind the system navigation
  /// bar background, that is 1dp higher. When using colors with opacity on
  /// the background and the divider, one have to consider the sum of the
  /// opacity for both colors to get the effective translucent color.
  ///
  /// Use and support for the [opacity] value on the system navigation bar
  /// is supported starting from Flutter 2.5. This PR once it lands in
  /// stable will also for more predictable and consistent behavior limit its
  /// functionality to SDK >= 29: https://github.com/flutter/engine/pull/28616
  ///
  /// By default [themedSystemNavigationBar] does not set any system overlay
  /// for the status bar. In Flutter SDK the top status bar has its own built in
  /// [SystemUiOverlayStyle] as a part of [AppBar] and [AppBarTheme].
  /// [FlexColorScheme] also manages the [SystemUiOverlayStyle] for the status
  /// bar via it. However, if your screen has no [AppBar] you can use the
  /// property [noAppBar] and [invertStatusIcons] to affect the look of the
  /// status icons when there is no [AppBar] present on the page, this is
  /// useful e.g. for splash and intro screens.
  static SystemUiOverlayStyle themedSystemNavigationBar(
    BuildContext? context, {

    /// Use a divider line on the top edge of the system navigation bar.
    ///
    /// On Android 11 (SDK30) there is an issue when using the system
    /// divider, see: https://github.com/flutter/flutter/issues/100027
    /// Recommend avoiding trying to remove or enable the system navbar
    /// divider with this feature until this issue is solved.
    /// When you use fully transparent system navigation bar the divider is
    /// removed, so at least that works OK.
    ///
    /// Based on Flutter SDK docs, the divider on the navigation bar, is on
    /// respected on Android P (= Pie = SDK API 28 = Android 9) or higher. But
    /// based on our findings it does not work until Android 10 (SDK29 or
    /// higher.
    ///
    /// Important: The divider is actually a layer behind the system navigation
    /// bar background, that is 1dp higher. When using colors with opacity on
    /// the background and the divider, one have to consider the sum of the
    /// opacity for both colors to get the effective translucent color.
    ///
    /// Defaults to null.
    ///
    /// Keeping it null, by omission or passing null, always  omits the call
    /// to set any divider color in the created [SystemUiOverlayStyle].
    final bool? useDivider,

    /// Opacity value for the system navigation bar.
    ///
    /// The opacity value is applied to the provided `systemNavigationBarColor`
    /// or if it is null, to the color determined by `systemNavBarStyle`.
    ///
    /// Defaults to 1, fully opaque.
    ///
    /// This feature is supported starting from Flutter 2.5.
    /// Be aware that it only works on Android SDK >= 29. There may be
    /// some issues on Android SDK < 29 until this PR lands in stable:
    /// https://github.com/flutter/engine/pull/28616
    ///
    /// This issue is a good source for more information on current state
    /// of transparent navigation bars in Flutter on Android:
    /// https://github.com/flutter/flutter/issues/90098.
    final double opacity = 1,

    /// Set this to true if you do not use a Material AppBar and want
    /// a uniform background where the status bar's icon region is.
    ///
    /// If you page does not have an [AppBar] you can also use this
    /// [AnnotatedRegion] helper remove the top status bar scrim color
    /// on the top icon status bar. set this to true to do soe.
    ///
    /// A typical use case would be pages like splash screens and intro
    /// screens that don't use an AppBar. The Material AppBar uses its own
    /// `SystemUiOverlayStyle` so don't use this with an AppBar, set the style
    /// on the AppBar theme instead. However, if you don't have an [AppBar] this
    /// is a convenient way of to remove the top system icon scrim for a more
    /// clean full screen look on Android.
    final bool noAppBar = false,

    /// Set to true to invert top status bar icons like, battery, network,
    /// wifi icons etc. in relation to their normal theme brightness related
    /// color.
    ///
    /// Defaults to false.
    ///
    /// This setting works well together with the `noAppBar` flag to make an
    /// even cleaner looking splash screen by making the
    /// top status bar icons less visible or even invisible.
    ///
    /// On a white background the status icons will be invisible, and if a
    /// fully black background is used in dark mode, they will be invisible
    /// in dark mode too. This can be used to create clean screen with no
    /// app bar and no status icons.
    ///
    /// For no status bar and and system navigation bar, you can also try using:
    /// `SystemChrome.setEnabledSystemUIOverlays(<SystemUiOverlay>[]);` to
    /// remove the top status bar and bottom navigation bar completely. When
    /// using that method there are however issues with them showing up again
    /// on navigation and when keyboard becomes visible, or app is restored
    /// from being in the background while using another app. You
    /// also have to manage putting the overlays back yourself manually with
    /// `SystemChrome.setEnabledSystemUIOverlays(SystemUiOverlay.values)` when
    /// moving away from the screen that had removed them. Using an
    /// `AnnotatedRegion` with `themedSystemNavigationBar` and both `noAppBar`
    /// and `invertStatusIcons` set to true, you can avoid these issues. You are
    /// however limited to using background white, in light mode and black in
    /// dark mode, if you want the status bar to be totally invisible and
    /// navigation bar to blend in with the background completely.
    final bool invertStatusIcons = false,

    /// The [FlexSystemNavBarStyle] used to determine the background color
    /// for the system navigation bar. Used when systemNavigationBarColor
    /// is null and context is not null, so theme colors corresponding to it
    /// can be used for the background color.
    ///
    /// Defaults to [FlexSystemNavBarStyle.background].
    final FlexSystemNavBarStyle systemNavBarStyle =
        FlexSystemNavBarStyle.background,

    /// Background color of the system navigation bar. If null the theme of
    /// context `colorScheme.background` will be used as background color.
    ///
    /// The point with this static helper is to give you a background color
    /// themed system navigation bar automatically. If you for some reason
    /// want a different color you can still override it this property.
    ///
    /// If `context` is null, `nullContextBrightness` will be used as brightness
    /// value and it will determine if the background is white (for
    /// Brightness.light) or black (for Brightness.dark) if this property is
    /// also null. The null context is mostly used for simple unit testing
    /// with no context, but can also be used to make a `SystemUiOverlayStyle`
    /// with this helper without having a context.
    final Color? systemNavigationBarColor,

    /// Optional color for the system navigation bar divider. A divider will
    /// only be present if `useDivider` is true and in this color if a
    /// value was given to it.
    ///
    /// If a color is not given the `Color(0xFF2C2C2C)` will be used in
    /// dark mode and the color `Color(0xFFDDDDDD)` will be used in light mode,
    /// as the divider color for the system navigation bar.
    ///
    /// Based on Flutter SDK docs, the divider on the navigation bar, is on
    /// respected on Android P (= Pie = SDK API 28 = Android 9) or higher. But
    /// based on our findings it does not work until Android 10 (SDK29 or
    /// higher.
    ///
    /// Important: The divider is actually a layer behind the system navigation
    /// bar background, that is 1dp higher. When using colors with opacity on
    /// the background and the divider, one have to consider the sum of the
    /// opacity for both colors to get the effective translucent color.
    final Color? systemNavigationBarDividerColor,

    /// Brightness used if context is null, mostly used for simple unit testing,
    /// with no context present. However, it can also be used to make a
    /// `SystemUiOverlayStyle` without having a context.
    ///
    /// Defaults to Brightness.light.
    final Brightness nullContextBrightness = Brightness.light,

    /// Deprecated property, use systemNavigationBarColor instead.
    @Deprecated('This property is deprecated use systemNavigationBarColor '
        'instead. Deprecated in v2.0.0.')
        Color? nullContextBackground,
  }) {
    double usedOpacity = opacity;
    if (usedOpacity < 0) usedOpacity = 0;
    if (usedOpacity > 1) usedOpacity = 1;
    // If the systemNavBarStyle is FlexSystemNavBarStyle.transparent
    // set opacity to fully transparent.
    if (systemNavBarStyle == FlexSystemNavBarStyle.transparent) {
      usedOpacity = 0.0;
    }
    // If opacity is specified, we need to enable SystemUiMode.edgeToEdge to
    // be able to see content scrolling behind the transparent bar. We only do
    // so when we have any opacity specified.
    if (usedOpacity < 1) {
      SystemChrome.setEnabledSystemUIMode(SystemUiMode.edgeToEdge);
    }
    // Background color logic.
    //
    // If systemNavigationBarColor is null, we assign nullContextBackground
    // to it, that may also be null. This is done for backwards compatibility.
    final Color? navigationBarColor =
        systemNavigationBarColor ?? nullContextBackground;
    // If context was null, use nullContextBrightness as brightness value.
    final bool isDark = context != null
        ? Theme.of(context).brightness == Brightness.dark
        : nullContextBrightness == Brightness.dark;
    // Get the defined effective background color for the used style.
    // This is not pretty, but wanted a final for the flexBackground.
    final Color flexBackground = (context != null)
        ? systemNavBarStyle == FlexSystemNavBarStyle.system
            ? (isDark ? Colors.black : Colors.white)
            : systemNavBarStyle == FlexSystemNavBarStyle.background
                ? Theme.of(context).colorScheme.background
                : systemNavBarStyle == FlexSystemNavBarStyle.surface
                    ? Theme.of(context).colorScheme.surface
                    : systemNavBarStyle ==
                            FlexSystemNavBarStyle.scaffoldBackground
                        ? Theme.of(context).scaffoldBackgroundColor
                        : Theme.of(context).scaffoldBackgroundColor
        : (isDark ? Colors.black : Colors.white);
    // If a systemNavigationBarColor color is given, it will always be used,
    // If it is not given, we use above flexBackground.
    final Color background = navigationBarColor ?? flexBackground;

    // TODO(rydmike): Remove SysNavBar workaround when issue #100027 solved.
    // See issue: https://github.com/flutter/flutter/issues/100027
    // Remove the workaround below when the solution to the issue has landed in
    // in Flutter stable channel.
    //
    // A divider will be applied if `useDivider` is true and it will
    // use provided `systemNavigationBarDividerColor` if a value was given,
    // or fallback to suitable theme mode default divider colors if no
    // color was given.
    //
    // The logic below is intended to keep the `dividerColor` used in the
    // [SystemUiOverlayStyle] as null as long as `useDivider` is null. As soon
    // as it is not, it will set a Divider color, also with `false` value. With
    // false it will be set to resulting background color in order to hide the
    // divider by making it background colored. This is a way to remove
    // the divider if it has been enabled earlier, since you cannot remove it
    // with a null color value after it has been enabled with any known
    // `SystemUiOverlayStyle` and `SystemChrome` call. The false value then
    // provide means to at least hide it again, but it will still be there.
    //
    // Worth noticing is also that the opacity does not have any effect on
    // divider color in SDK<29 of Android. We apply some opacity anyway because
    // if you are using transparent system navigation bar on Android API30 or
    // higher it does work, and it looks nicer when it has some transparency
    // if the navbar is also transparent.
    //
    // Also some of the crazy hoops are designed to work around this issue for
    // Android 11: https://github.com/flutter/flutter/issues/100027
    Color? dividerColor;
    // If we have opacity on the navbar, we should have some on the divider too
    // when we have a divider, we use some, but not a lot, we do want to keep
    // visible and not fade a way with background opacity, since a divider was
    // requested.
    final double dividerOpacity = usedOpacity < 1 ? 0.5 : 1;
    if (useDivider == null || !useDivider) {
      // The dividerColor is already null from declaration above with no value,
      // here we are just being explicit that this is the case where we want a
      // null color value for the divider as well in order to not include it
      // in the `SystemUiOverlayStyle` at all.
      dividerColor = Colors.transparent; //background.withAlpha(1);
    } else {
      // We should have a divider, but have no given color, use defaults.
      if (systemNavigationBarDividerColor == null) {
        dividerColor = isDark
            ? const Color(0xFF2C2C2C).withOpacity(dividerOpacity)
            : const Color(0xFFDDDDDD).withOpacity(dividerOpacity);
      } // We should have a divider, with a given color.
      else {
        dividerColor =
            systemNavigationBarDividerColor.withOpacity(dividerOpacity);
      }
    }

    // Need to determine effective AppBar background color, so we can compute
    // its brightness need for status icons. Used partially for workarounds to
    // https://github.com/flutter/flutter/issues/100027
    late Color appBarColor;
    if (context == null) {
      // This is for testing we set it to same as navbar.
      appBarColor = background;
    } else {
      final ThemeData theme = Theme.of(context);
      final ColorScheme colorScheme = theme.colorScheme;
      final AppBarTheme appBarTheme = AppBarTheme.of(context);
      appBarColor = appBarTheme.backgroundColor ??
          (colorScheme.brightness == Brightness.dark
              ? colorScheme.surface
              : colorScheme.primary);
    }
    final Brightness appBarBrightness =
        ThemeData.estimateBrightnessForColor(appBarColor);

    // First make finals for each property, so we can modify the logic just
    // once when needed. Used this to experiment with work around for:
    // https://github.com/flutter/flutter/issues/100027
    // Nothing worked satisfactory, Android 11 will just have to wait for fix!
    final Color? statusBarColor =
        noAppBar ? Colors.transparent : null; //const Color(0x40000000);
    final Brightness? statusBarBrightness =
        noAppBar ? (isDark ? Brightness.dark : Brightness.light) : null;
    final Brightness? statusBarIconBrightness = noAppBar
        ? invertStatusIcons
            ? (isDark ? Brightness.dark : Brightness.light)
            : (isDark ? Brightness.light : Brightness.dark)
        : invertStatusIcons
            ? appBarBrightness
            : null;
    final Color sysNavigationBarColor = background.withOpacity(usedOpacity);
    final Color sysNavigationBarDividerColor =
        invertStatusIcons ? Colors.transparent : dividerColor;
    final Brightness systemNavigationBarIconBrightness = invertStatusIcons
        ? (isDark ? Brightness.dark : Brightness.light)
        : (isDark ? Brightness.light : Brightness.dark);

    // Tried work around for A11 issue, including calling SystemUiOverlayStyle
    // with different styles, but nothing worked OK, this
    // double SystemUiOverlayStyle call is the best option for now.
    SystemUiOverlayStyle(
      // The top status bar settings.
      systemStatusBarContrastEnforced: false,
      statusBarColor: statusBarColor,
      statusBarBrightness: statusBarBrightness,
      statusBarIconBrightness: statusBarIconBrightness,
      // The bottom navigation bar settings.
      systemNavigationBarContrastEnforced: false,
      systemNavigationBarColor: sysNavigationBarColor,
      systemNavigationBarDividerColor: sysNavigationBarDividerColor,
      systemNavigationBarIconBrightness: systemNavigationBarIconBrightness,
    );
    //
    return SystemUiOverlayStyle(
      // The top status bar settings.
      systemStatusBarContrastEnforced: false,
      statusBarColor: statusBarColor,
      statusBarBrightness: statusBarBrightness,
      statusBarIconBrightness: statusBarIconBrightness,
      // The bottom navigation bar settings.
      systemNavigationBarContrastEnforced: false,
      systemNavigationBarColor: sysNavigationBarColor,
      // Important for the workaround that this is removed in 2nd call.
      // systemNavigationBarDividerColor: sysNavigationBarDividerColor,
      systemNavigationBarIconBrightness: systemNavigationBarIconBrightness,
    );
  }

  /// Create a primary Material color swatch from a given [color].
  ///
  /// This function is since version 5.0.0 no longer used by FlexColorScheme.
  /// In previous version it was used by [FlexColorScheme.toTheme] to provide
  /// [ColorScheme.primary] matching colors for [ThemeData.primaryColorLight],
  /// [ThemeData.primaryColorDark] and [ThemeData.secondaryHeaderColor].
  ///
  /// Since algorithm does not produce a correct [MaterialColor], it did not
  /// work so well if the provided color was not of roughly a mid point 500
  /// index equivalent. So it worked well for light theme mode, but not so well
  /// for dark theme mode themes were [ColorScheme.primary] is typically much
  /// lighter than then [MaterialColor] 500 index. FlexColorScheme moved to just
  /// using lighten and darken to provide primary color matching colors to
  /// above mentioned colors. Since the colors are very rarely used and on a
  /// deprecation path in Flutter SDK they are not so critical.
  ///
  /// Since this function is no longer need by this library, it may be
  /// deprecated and removed. Deprecation could e.g. happen in FlexColorScheme
  /// version 6, and removal in version 7.
  ///
  /// There reason why it is not deprecated already is because I would like to
  /// replace it with the correct Material 2 [MaterialColor] algorithm, which
  /// is not available in Dart.
  /// There are reversed engineered JS versions of the official Material Color
  /// algorithm made from the Material Guide web tools. If anybody has the
  /// energy to make a Dart version of it, that would be fabulous.
  /// SO discussion here:
  /// https://stackoverflow.com/questions/32942503/material-design-color-palette
  ///
  /// Starting points here:
  /// - https://github.com/mbitson/mcg/issues/19
  /// - Good candidate: https://github.com/eugeneford/material-palette-generator
  /// - https://github.com/edelstone/material-palette-generator
  ///
  /// Old documentation for using [createPrimarySwatch].
  ///
  /// The provided [color] is used as the Material swatch default color 500
  /// in the returned swatch, with lighter hues for lower indexes and darker
  /// shades for higher index values.
  ///
  /// If you give this function a standard Material color index 500 value,
  /// eg `Colors.red[500]` it will not return the same swatch as `Colors.red`.
  /// This function is an approximation and gives an automated way of creating
  /// a Material like primary swatch.
  ///
  /// The used algorithm is identical to the same named function
  /// found in ColorTools in FlexColorPicker at
  /// https://pub.dev/packages/flex_color_picker.
  static MaterialColor createPrimarySwatch(final Color? color) {
    // Null default fallback is default material primary light color.
    final Color usedColor = color ?? FlexColor.materialLightPrimary;
    const List<double> strengths = <double> //
        [0.05, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9];
    final Map<int, Color> swatch = <int, Color>{};
    final int r = usedColor.red;
    final int g = usedColor.green;
    final int b = usedColor.blue;
    for (final double strength in strengths) {
      final double ds = 0.5 - strength;
      swatch[(strength * 1000).round()] = Color.fromRGBO(
        r + ((ds < 0 ? r : (255 - r)) * ds).round(),
        g + ((ds < 0 ? g : (255 - g)) * ds).round(),
        b + ((ds < 0 ? b : (255 - b)) * ds).round(),
        1,
      );
    }
    // The above gives a starting point, this tunes it a bit better, still far
    // from the real algorithm.
    swatch[50] = swatch[50]!.lighten(18);
    swatch[100] = swatch[100]!.lighten(16);
    swatch[200] = swatch[200]!.lighten(14);
    swatch[300] = swatch[300]!.lighten(10);
    swatch[400] = swatch[400]!.lighten(6);
    swatch[700] = swatch[700]!.darken(2);
    swatch[800] = swatch[800]!.darken(3);
    swatch[900] = swatch[900]!.darken(4);
    return MaterialColor(usedColor.value, swatch);
  }

  //****************************************************************************
  //
  // MAKE THE THEME
  //
  // Getter: toTheme
  //
  //****************************************************************************

  /// Returns the [ThemeData] object defined by [FlexColorScheme] properties
  /// and its theming logic.
  ///
  /// After you have defined your scheme with [FlexColorScheme] or one of its
  /// factories [FlexColorScheme.light], [FlexColorScheme.dark], use
  /// [toTheme] to get the resulting [ThemeData] object defined by
  /// your [FlexColorScheme] definition.
  ///
  /// The returned [ThemeData] contains some opinionated modifications and dark
  /// theme corrections, compared to what you get if you would just use the
  /// standard [ThemeData.from] a [ColorScheme]. You can always override these
  /// with your own theme modifications by using the [ThemeData.copyWith]
  /// method on the resulting theme.
  ///
  /// The differences from the standard [ThemeData.from] factory are:
  ///
  /// * `ScaffoldBackgroundColor` has its own color property in FlexColorScheme
  ///   and can if so desired differ from the `ColorScheme.background` color.
  ///   When using primary color blended surfaces and backgrounds, it is
  ///   important to be able to vary the very prominent ScaffoldBackgroundColor
  ///   separately from other surfaces and backgrounds.
  ///
  /// * The `dialogBackgroundColor` uses the `ColorScheme.surface` color
  ///   instead of the default `ColorScheme.background`. In order to preserve
  ///   the `elevationOverlayColor` in dark mode when `ColorScheme.surface` and
  ///   `ColorScheme.background` differs due to different surface blends, the
  ///   `ColorScheme.surface` was used to ensure dialogs that are always
  ///   elevated gets the overlay color applied in dark theme mode. For more
  ///   info see:
  ///   [issue #90353](https://github.com/flutter/flutter/issues/90353).
  ///
  ///  * The `indicatorColor` is same as `effectiveTabColor` which uses a
  ///    function with logic to determine its color based on if a TabBarTheme
  ///    was selected that should work on current AppBar background color,
  ///    or on surface/background colors.
  ///
  ///  * For `toggleableActiveColor` the `ColorScheme.secondary` color is used.
  ///    The Flutter default just uses the default `ThemeData` colors and
  ///    not the actual colors you define in the `ColorScheme` you create your
  ///    theme from. Perhaps an oversight in Flutter?
  ///    See issue: https:///github.com/flutter/flutter/issues/65782.
  ///    This color property will be deprecated in Flutter, see issue
  ///    [91772](https://github.com/flutter/flutter/issues/91772).
  ///
  ///  * Flutter themes created with `ThemeData.from` does not define any color
  ///    scheme related color for the `primaryColorDark` color, this method
  ///    does.  See issue: https:///github.com/flutter/flutter/issues/65782.
  ///    The `ThemeData.from` leaves this color at `ThemeData` factory default,
  ///    this may not match your scheme. Widgets seldom use this color, so the
  ///    issue is rarely seen.
  ///    This color property will be deprecated in Flutter, see issue
  ///    [91772](https://github.com/flutter/flutter/issues/91772).
  ///
  ///  * Flutter themes created with `ThemeData.from` does not define any color
  ///    scheme based color for the `primaryColorLight` color, this method does.
  ///    See issue: https:///github.com/flutter/flutter/issues/65782.
  ///    The `ThemeData.from` leaves this color at `ThemeData` factory default
  ///    this may not match your scheme. Widgets seldom use this color, so the
  ///    issue is rarely seen.
  ///    This color property will be deprecated in Flutter, see issue
  ///    [91772](https://github.com/flutter/flutter/issues/91772).
  ///
  ///  * Flutter themes created with `ThemeData.from` does not define any color
  ///    scheme based color for the `secondaryHeaderColor` color, this method
  ///    does. See issue: https:///github.com/flutter/flutter/issues/65782.
  ///    `ThemeData.from` leaves this color at `ThemeData` factory default this
  ///    may not match your scheme. Widgets seldom use this color, so the issue
  ///    is rarely seen.
  ///    This color property will be deprecated in Flutter, see issue
  ///    [91772](https://github.com/flutter/flutter/issues/91772).
  ///
  ///  * Background color for `AppBarTheme` can use a custom color theme
  ///    in both light and dark themes, that is not dependent on theme
  ///    primary or surface color.
  ///    In the versions prior to Flutter 2.0.0 doing this was difficult to do.
  ///    As presented in https://github.com/flutter/flutter/issues/50606
  ///    A new feature in Flutter 2.0.0 implemented via:
  ///    https://github.com/flutter/flutter/pull/71184 makes this easy and
  ///    better. FlexColorScheme's implementation has been changed to use this
  ///    new AppBarTheme feature starting with version 2.0.0-nullsafety.2.
  ///
  ///  * The `AppBarTheme` elevation defaults to 0, an iOs style influenced
  ///    opinionated choice. It can easily be adjusted directly in the
  ///    `FlexColorScheme` definition with property value `appBarElevation`
  ///    without creating a sub theme or using `copyWith`.
  ///    For the main less used constructor of `FlexColorScheme` it is required
  ///    and cannot be null. The `FlexColorScheme` `light` and `dark` factories
  ///    can be null but it will default to 0 if null.
  ///
  ///  * The `bottomAppBarColor` uses color scheme background color to match the
  ///    background color of the drawer, bottom navigation bar, possible side
  ///    menu and system navigation bar on android (if theming of it is used).
  ///    This is a slight change from the ColorScheme default that uses
  ///    surface color.
  ///
  ///  * The `BottomAppBarTheme` elevation defaults to `appBarElevation` or 0 if
  ///    it is null. It can easily be adjusted directly in the
  ///    `FlexColorScheme` definition with property
  ///    value `bottomAppBarElevation` without creating a sub theme or
  ///    using `copyWith`.
  ///
  ///  * In `TextSelectionThemeData`, the standard for `selectionColor` is
  ///    `colorScheme.primary` with opacity value `0.4` for dark-mode and `0.12`
  ///    for light mode. Here primary with `0.5` for dark-mode and `0.3` for
  ///    light mode is used. The standard for `selectionHandleColor` is
  ///    `colorScheme.primary`, here we use the slightly darker shade
  ///    `primaryColorDark` instead, which does not have a proper color
  ///    scheme color value in Flutter standard `ColorScheme` based themes.
  ///
  ///  * A predefined slightly opinionated [InputDecorationTheme] is used. It
  ///    sets `filled` to `true` and fill color to color scheme primary color
  ///    with opacity `0.035` in light mode and opacity `0.06` in dark-mode.
  ///
  ///  * The property `fixTextFieldOutlineLabel` is set to `true` by default,
  ///    it looks better. The only reason why it is not the default in Flutter,
  ///    is for default backwards legacy design compatibility.
  ///
  ///  * For [ThemeData.buttonTheme] the entire color scheme is passed to its
  ///    `colorScheme` property and it uses `textTheme` set to
  ///    `ButtonTextTheme.primary`, plus minor changes to padding and tap target
  ///    size. These modifications make the old buttons almost match the
  ///    default design and look of their corresponding newer buttons.
  ///    Thus the `RaisedButton` looks very similar to `ElevatedButton`,
  ///    `OutlineButton` to `OutlinedButton` and `FlatButton` to `TextButton`.
  ///    There are some differences in margins and looks, especially in
  ///    dark-mode, but they are very similar.
  ///
  ///  * The default theme for Chips contain a design bug that makes the
  ///    selected `ChoiceChip()` widget look disabled in dark-mode, regardless
  ///    if was created with `ThemeData` or `ThemeData.from` factory.
  ///    See issue: https:///github.com/flutter/flutter/issues/65663
  ///    The [ChipThemeData] modification used here fixes the issue.
  ///
  /// * For [TabBarTheme], the Flutter standard selected tab and indicator
  ///   color is onSurface in dark mode and on Primary in light mode, which is
  ///   designed to fit an AppBar colored TabBar. This is kept, and the default
  ///   via [FlexTabBarStyle.forAppBar] style, with a minor modification. If
  ///   AppBar is "light", then black87 is used, not black, it is the same as
  ///   the textTheme on AppBar in light app bar brightness.
  ///   If the [FlexTabBarStyle.forBackground] style was used, the
  ///   selected  color is always color scheme primary color, which works well
  ///   on surface, background and scaffold background colors.
  ///
  ///   The unselected TabBar color when [FlexTabBarStyle.forBackground] style
  ///   is used, is always the onSurface color with 60% opacity. This is also
  ///   the color if the AppBar background color brightness is light AND its
  ///   color is white, surface or background colored.
  ///   Otherwise when the style [FlexTabBarStyle.forAppBar] is used, the
  ///   unselected tab bar color is the selected tab color with 70% opacity.
  ///   This opacity value is the same  as Flutter default for the default
  ///   theme that is also designed for AppBar usage.
  ///
  /// * The [BottomNavigationBarThemeData] uses color scheme primary color for
  ///   the selected item in both light and dark theme. Flutter SDK defaults
  ///   to secondary color in dark mode. Using only primary color
  ///   is a design used on iOS by default for the bottom navigation bar. We
  ///   agree and think it looks better as the default choice for apps also
  ///   in dark mode.
  ///
  /// * Default tooltip theme in Flutter is currently a bit flawed on desktop
  ///   and web, because it defaults to using a very small font (10 dp).
  ///   See issue: https:///github.com/flutter/flutter/issues/71429
  ///
  ///   The default theming also does not handle multiline tooltips very well.
  ///   The here used [TooltipThemeData] theme design corrects both these
  ///   issues. It uses 12 dp font on desktop and web instead of 10 dp,
  ///   and some padding instead of a height constraint to ensure that
  ///   multiline tooltips look nice too.
  ///
  ///   FlexColorScheme also includes a new boolean property
  ///   [tooltipsMatchBackground], that can be toggled to not used Flutter's
  ///   Material default that has a theme mode
  ///   inverted background. Tooltips using light background in light theme
  ///   and dark in dark, are commonly used on the Windows desktop platform.
  ///   You can tie the extra property to used platform to make an automatic
  ///   platform adaptation of the tooltip style if you like, or give users
  ///   a preference toggle the tooltip style to their liking.
  ///
  /// * The property [transparentStatusBar] is set to true by default and
  ///   used to make to the AppBar one-toned on Android device like on iOS.
  ///   Set it to `false` to restore default Android design.
  ///
  ///   > It would be nice if we could also make the system navigation button
  ///   > area on Android transparent via a theme, but it does not work.
  ///   > The style is doable, but requires modifying Android config files, not
  ///   > possible from Flutter only (as per current information).
  ///   > Related issue: https:///github.com/flutter/flutter/issues/69999.
  ///   >
  ///   > FlexColorScheme offers a static helper [themedSystemNavigationBar]
  ///   > that allows us to easily create an annotated region for the system
  ///   > navigation bar that uses the active color scheme and theme mode to
  ///   > make it at least use a correctly colored theme colored background
  ///   > for the active theme.
  ///   > See example 5 for a demo on how to use this.
  ThemeData get toTheme {
    // We on purpose shadow deprecated this.useSubThemesData that has
    // been deprecated, and set it it true if a none null subThemesData was
    // provided.
    final bool useSubThemes = subThemesData != null;
    // If we did not have any sub-theme data, we make one instead that cannot
    // be null. It makes the logic easier to deal with when we create
    // sub-themes, when it cannot be nullable.
    final FlexSubThemesData subTheme =
        subThemesData ?? const FlexSubThemesData();

    // Get the effective standard Flutter ColorScheme from the provided
    // brightness and provided or computed or default colors.
    final ColorScheme colorScheme = toScheme;

    // A convenience bool to check if this theme is for light or dark mode
    final bool isDark = colorScheme.brightness == Brightness.dark;

    // Use passed in target platform, else actual host platform.
    final TargetPlatform effectivePlatform = platform ?? defaultTargetPlatform;

    // Used Typography deviates from the Flutter standard that _still_ uses the
    // old Typography.material2014 in favor of the newer Typography.material2018
    // as default, if one is not provided. We use the Material 2 correct 2018
    // as the default when not using M3. If using M3 or opting-in
    // via sub-themes on using M3 TextTheme geometry, the new 2021 Typography
    // is used that was released in Flutter 3.0.0.
    final Typography effectiveTypography = typography ??
        (((useSubThemes && subTheme.useTextTheme) || useMaterial3)
            ? Typography.material2021(platform: effectivePlatform)
            : Typography.material2018(platform: effectivePlatform));

    // We need the text themes locally for the theming, so we must form them
    // fully using the same process that the ThemeData() factory uses.
    TextTheme defText =
        isDark ? effectiveTypography.white : effectiveTypography.black;
    final bool primaryIsDark =
        ThemeData.estimateBrightnessForColor(colorScheme.primary) ==
            Brightness.dark;
    TextTheme defPrimaryText =
        primaryIsDark ? effectiveTypography.white : effectiveTypography.black;

    if (fontFamily != null) {
      // ThemeData uses this to apply a font from fontFamily. It works OK, but
      // it resets all typography and it uses regular style and weight
      // for all styles in the text theme. Consider defining the text theme
      // explicitly via textTheme and primaryTextTheme with the custom
      // font applied, at least if you want to use custom fonts and keep the
      // standard typography, or supply your own complete typography with your
      // custom text theme.
      defText = defText.apply(fontFamily: fontFamily);
      defPrimaryText = defPrimaryText.apply(fontFamily: fontFamily);
    }
    // We are using sub themes and blend colors on text themes. If surfaces and
    // background are not set to use blends, the effect will be slightly
    // different, a bit less colorful, but only very marginally.
    if (useSubThemes && subTheme.blendTextTheme) {
      // Use the on color for surface or background that gives us better
      // contrast. Finding the right one by comparing red values seemed
      // to work well enough.
      final Color onColor = isDark
          ? (colorScheme.onBackground.red < colorScheme.onSurface.red)
              ? colorScheme.onSurface
              : colorScheme.onBackground
          : (colorScheme.onBackground.red > colorScheme.onSurface.red)
              ? colorScheme.onSurface
              : colorScheme.onBackground;
      // Calculate colors for the different TextStyles, these are just best
      // approximations, color blend strength is a bit inline with opacities on
      // the 2018 typography, but that might not match what is will be used for
      // color and opacity on Typography in Material 3. Could not find
      // definitions for it in the Material 3 guide. They might also be
      // just flat one color tone for all sizes. That would be simpler, but
      // even that color is not know yet.
      final Color headerColor = isDark
          ? onColor.blend(colorScheme.primary, 40)
          : onColor.blend(colorScheme.primary, 50);
      final Color mediumColor = isDark
          ? onColor.blend(colorScheme.primary, 22)
          : onColor.blend(colorScheme.primary, 40);
      final Color smallColor = isDark
          ? onColor.blend(colorScheme.primary, 20)
          : onColor.blend(colorScheme.primary, 30);
      // Apply the computed colors. Most fonts have no opacity when using this
      // type of styling, they are computed with a color matching their
      // background. This does not work so well if you need to put text on
      // a completely different colored container than the background color.
      // Which is why this feature can be opted out of.
      // M3 has separate on colors for all colorscheme colors that can also
      // be used for color matched text on each color. However, this slightly
      // primary colored default text works very well for the slight primary
      // colored M3 "neutral" surface colors with a primary hint too.
      defText = defText.copyWith(
        displayLarge: defText.displayLarge!.copyWith(color: headerColor),
        displayMedium: defText.displayMedium!.copyWith(color: headerColor),
        displaySmall: defText.displaySmall!.copyWith(color: headerColor),
        headlineLarge: defText.headlineLarge!.copyWith(color: headerColor),
        headlineMedium: defText.headlineMedium!.copyWith(color: headerColor),
        headlineSmall: defText.headlineSmall!.copyWith(color: mediumColor),
        titleLarge: defText.titleLarge!.copyWith(color: mediumColor),
        titleMedium: defText.titleMedium!.copyWith(color: mediumColor),
        titleSmall: defText.titleSmall!.copyWith(color: smallColor),
        bodyLarge: defText.bodyLarge!.copyWith(color: mediumColor),
        bodyMedium: defText.bodyMedium!.copyWith(color: mediumColor),
        // Caption in English2018 has heading level opacity in Material2.
        // I noticed it still needs some, eg ListTile uses the color from
        // caption, with its opacity, to make the subtitles more muted, this
        // is an important design effect that we get automatically if we give
        // it some opacity, just not going to give it as much, since we also
        // have colors and it is imo a bit too low contrast in M2 anyway.
        bodySmall: defText.bodySmall!.copyWith(
            color: mediumColor.withAlpha(isDark ? 0xCC : 0xBF)), // 80% & 75%
        labelLarge: defText.labelLarge!.copyWith(color: mediumColor),
        labelMedium: defText.labelMedium!.copyWith(color: smallColor),
        labelSmall: defText.labelSmall!.copyWith(color: smallColor),
      );
      // Equivalent color blend calculations for primary text theme.
      final Color headerPrimary = primaryIsDark
          ? colorScheme.onPrimary.blend(colorScheme.primary, 16)
          : colorScheme.onPrimary.blend(colorScheme.primary, 10);
      final Color mediumPrimary = primaryIsDark
          ? colorScheme.onPrimary.blend(colorScheme.primary, 8)
          : colorScheme.onPrimary.blend(colorScheme.primary, 5);
      final Color smallPrimary = primaryIsDark
          ? colorScheme.onPrimary.blend(colorScheme.primary, 7)
          : colorScheme.onPrimary.blend(colorScheme.primary, 4);
      defPrimaryText = defPrimaryText.copyWith(
        displayLarge:
            defPrimaryText.displayLarge!.copyWith(color: headerPrimary),
        displayMedium:
            defPrimaryText.displayMedium!.copyWith(color: headerPrimary),
        displaySmall:
            defPrimaryText.displaySmall!.copyWith(color: headerPrimary),
        headlineLarge:
            defPrimaryText.headlineLarge!.copyWith(color: headerPrimary),
        headlineMedium:
            defPrimaryText.headlineMedium!.copyWith(color: mediumPrimary),
        headlineSmall:
            defPrimaryText.headlineSmall!.copyWith(color: mediumPrimary),
        titleLarge: defPrimaryText.titleLarge!.copyWith(color: mediumPrimary),
        titleMedium: defPrimaryText.titleMedium!.copyWith(color: mediumPrimary),
        titleSmall: defPrimaryText.titleSmall!.copyWith(color: smallPrimary),
        bodyLarge: defPrimaryText.bodyLarge!.copyWith(color: mediumPrimary),
        bodyMedium: defPrimaryText.bodyMedium!.copyWith(color: mediumPrimary),
        bodySmall: defPrimaryText.bodySmall!.copyWith(
            color:
                mediumPrimary.withAlpha(primaryIsDark ? 0xD8 : 0xCC)), //85,70%)
        labelLarge: defPrimaryText.labelLarge!.copyWith(color: mediumPrimary),
        labelMedium: defPrimaryText.labelMedium!.copyWith(color: smallPrimary),
        labelSmall: defPrimaryText.labelSmall!.copyWith(color: smallPrimary),
      );
    }
    // Make our final complete TextTheme, by also merging in the two TextThemes
    // passed in via the constructor, adding any custom text theme definitions.
    final TextTheme effectiveTextTheme = defText.merge(textTheme);
    final TextTheme effectivePrimaryTextTheme =
        defPrimaryText.merge(primaryTextTheme);

    // Custom computed shades from primary color using alpha blends works well
    // for these rarely used colors that are on deprecation path in Flutter SDK.
    // https://github.com/flutter/flutter/issues/91772
    final Color primaryColorDark = isDark
        ? colorScheme.primary.blend(Colors.black, 45)
        : colorScheme.primary.blend(Colors.black, 40);
    final Color primaryColorLight = isDark
        ? colorScheme.primary.blend(Colors.white, 35)
        : colorScheme.primary.blend(Colors.white, 40);
    final Color secondaryHeaderColor = isDark
        ? colorScheme.primary.blend(Colors.black, 60)
        : colorScheme.primary.blend(Colors.white, 80);
    // AppBar background color:
    // - If a color is passed in, that is used first.
    // - If we use sub-themes, we use its scheme based color.
    // - If neither was given we use the surface color in dark mode and
    //   primary color in light mode, the same logic that Flutter SDK
    //   ThemeData.from factory sets the AppBar background color to.
    final Color effectiveAppBarColor = appBarBackground ??
        (useSubThemes && subTheme.appBarBackgroundSchemeColor != null
            ? FlexSubThemes.schemeColor(
                subTheme.appBarBackgroundSchemeColor!, colorScheme)
            : isDark
                ? colorScheme.surface
                : colorScheme.primary);
    final Brightness appBarBrightness =
        ThemeData.estimateBrightnessForColor(effectiveAppBarColor);
    Color appBarForeground =
        appBarBrightness == Brightness.dark ? Colors.white : Colors.black;
    // Icons are slightly black  transparent in light mode! This per SDK.
    Color appBarIconColor =
        appBarBrightness == Brightness.dark ? Colors.white : Colors.black87;
    // If we are using subThemes and blend text, use it for the AppBar text too.
    if (useSubThemes && subTheme.blendTextTheme) {
      if (appBarBrightness == Brightness.dark) {
        appBarForeground =
            FlexColor.lightSurface.blend(effectiveAppBarColor, 12);
      } else {
        appBarForeground =
            FlexColor.darkSurface.blend(effectiveAppBarColor, 12);
      }
      appBarIconColor = appBarForeground;
    }
    // Selected TabBar color is based on FlexTabBarStyle tabBarStyle.
    // The `flutterDefault` sets values corresponding to SDK Default behavior,
    // it can be used, but is not as useful as the `forAppBar` version which
    // is the default here.
    Color selectedTabColor() {
      switch (tabBarStyle) {
        case FlexTabBarStyle.flutterDefault:
          return isDark ? Colors.white : colorScheme.onPrimary;
        case FlexTabBarStyle.forBackground:
          return colorScheme.primary;
        case FlexTabBarStyle.forAppBar:
          return appBarBrightness == Brightness.light
              ? Colors.black87
              : Colors.white;
        case FlexTabBarStyle.universal:
          // TODO(rydmike): Need better FlexTabBarStyle.universal algo some day.
          return isDark
              ? colorScheme.primary.blendAlpha(Colors.white, 0xE6) // 90%
              : colorScheme.primary.blendAlpha(Colors.white, 0xB2); // 50%
      }
    }

    // Unselected TabBar color is based on FexTabBarStyle tabBarStyle.
    // The `flutterDefault` sets values corresponding to SDK Default behavior.
    Color unselectedTabColor() {
      switch (tabBarStyle) {
        case FlexTabBarStyle.flutterDefault:
          return selectedTabColor().withAlpha(0xB2); // 70%
        case FlexTabBarStyle.forBackground:
          return useSubThemes
              ? colorScheme.onSurface
                  .blendAlpha(colorScheme.primary,
                      kUnselectedBackgroundPrimaryAlphaBlend)
                  .withAlpha(kUnselectedAlphaBlend)
              : colorScheme.onSurface.withAlpha(0x99); // 60%
        case FlexTabBarStyle.forAppBar:
          return (appBarBrightness == Brightness.light &&
                  (effectiveAppBarColor == Colors.white ||
                      effectiveAppBarColor == colorScheme.surface ||
                      effectiveAppBarColor == colorScheme.background))
              ? colorScheme.onSurface.withAlpha(0x99) // 60%
              : selectedTabColor().withAlpha(0xB2); // 70% alpha
        case FlexTabBarStyle.universal:
          return isDark
              ? colorScheme.primary
                  .blendAlpha(Colors.white, 0xE6) // 90%
                  .withAlpha(0xB2) // 70% alpha
              : colorScheme.primary
                  .blendAlpha(Colors.white, 0x7F)
                  .withAlpha(0x7F); // 50%a
      }
    }

    // The current default theme for Material themed Tooltips are not ideal
    // choices for desktop https://material.io/components/tooltips#specs.
    // See issue: https://github.com/flutter/flutter/issues/71429
    // The font size of 10 dp is too small for desktops with pixel density
    // 1.0 so here we use 12 dp on desktop/Web and 14 dp on devices.
    double tooltipFontSize() {
      switch (effectivePlatform) {
        case TargetPlatform.macOS:
        case TargetPlatform.linux:
        case TargetPlatform.windows:
          return 12;
        case TargetPlatform.iOS:
        case TargetPlatform.fuchsia:
        case TargetPlatform.android:
          return 14;
      }
    }

    // This padding on tooltips fixes that default tooltips do not work well if
    // multi-row tooltips are used with the default fixed sized behavior.
    EdgeInsets tooltipPadding() {
      switch (effectivePlatform) {
        case TargetPlatform.macOS:
        case TargetPlatform.linux:
        case TargetPlatform.windows:
          return const EdgeInsets.fromLTRB(8, 3, 8, 4);
        case TargetPlatform.iOS:
        case TargetPlatform.fuchsia:
        case TargetPlatform.android:
          return const EdgeInsets.symmetric(horizontal: 16, vertical: 8);
      }
    }

    // TODO(rydmike): Monitor Flutter SDK deprecation of dividerColor.
    // Same as in ThemeData.from, but defined for use in the tooltip sub-theme.
    // If our onSurface is primary tinted it has an effect on this divider too.
    final Color dividerColor = colorScheme.onSurface.withAlpha(0x1E); // 12%
    // Make the effective input decoration theme, by using FCS sub themes
    // if opted in, otherwise use pre v4 version as before. This decoration
    // theme is also passed into the TimePickerTheme, so we get the same
    // style used there too.
    final InputDecorationTheme effectiveInputDecorationTheme = useSubThemes
        // V4 and later sub-theme based input decorator used.
        ? FlexSubThemes.inputDecorationTheme(
            colorScheme: colorScheme,
            baseSchemeColor: subTheme.inputDecoratorSchemeColor,
            radius: subTheme.inputDecoratorRadius ??
                subTheme.defaultRadius ??
                kButtonRadius,
            borderType: subTheme.inputDecoratorBorderType,
            filled: subTheme.inputDecoratorIsFilled,
            fillColor: subTheme.inputDecoratorFillColor,
            focusedBorderWidth: subTheme.thickBorderWidth,
            unfocusedBorderWidth: subTheme.thinBorderWidth,
            unfocusedHasBorder: subTheme.inputDecoratorUnfocusedHasBorder,
            unfocusedBorderIsColored:
                subTheme.inputDecoratorUnfocusedBorderIsColored)
        // Default one is also a bit opinionated, this is the FCS standard
        // in all previous versions before version 4.0.0. Kept for
        // backwards defaults compatibility.
        : InputDecorationTheme(
            // Extend filled property to previous always filled ones, defaults
            // to filled as before, but can now also be unfilled even if not
            // opted in on sub themes, by setting the property for it in
            // FlexSubThemesData.
            filled: subTheme.inputDecoratorIsFilled,
            fillColor: isDark
                ? colorScheme.primary.withAlpha(0x0F) // 6%
                : colorScheme.primary.withAlpha(0x09), // 3.5%
          );

    // Use themed interaction effects on hover, focus, highlight and splash?
    final bool themedEffects = useSubThemes && subTheme.interactionEffects;

    // Return the ThemeData object defined by the FlexColorScheme
    // properties and the designed opinionated theme design choices.
    return ThemeData(
      // These properties we just pass along to the standard ThemeData factory.
      // They are included in FlexColorScheme (FCS) so we do not have to
      // apply them via ThemeData copyWith separately for cases when we want
      // to use them in a FlexColorSchemes, which might often be the case. Some
      // of the values may be null and get defaults via the ThemeData() factory.
      fontFamily: fontFamily,
      visualDensity: visualDensity,
      useMaterial3: useMaterial3,
      extensions: extensions,
      // TextTheme properties use the same logic as in ThemeData, allowing us
      // to optionally define them. AccentTextTheme is omitted since it has
      // been deprecated in Flutter 2.5.0.
      textTheme: effectiveTextTheme,
      primaryTextTheme: effectivePrimaryTextTheme,
      // Pass along custom typography and platform.
      typography: effectiveTypography,
      platform: effectivePlatform,
      // Most definitions below are very close to the ones used by the Flutter
      // factory ThemeData.from() for creating a theme from a color scheme and
      // text theme.
      brightness: colorScheme.brightness,
      primaryColor: colorScheme.primary,
      canvasColor: colorScheme.background,
      // TODO(rydmike): Monitor Flutter SDK deprecation of scaffoldBackground.
      // See: https://github.com/flutter/flutter/issues/91772
      // Flutter standard for scaffoldBackgroundColor is colorScheme.background.
      // Here it is replaced with a separate color for the scaffold background,
      // so we can use a configuration with a separate scaffold background
      // color from scheme background and surface. Flutter's ThemeData.from
      // a ColorScheme cannot do this. The good old ThemeData factory can of
      // course, but color scheme based themes in Flutter cannot specify it
      // separately alone. We want to do so in order to make elegantly nuanced
      // primary color branded themes.
      scaffoldBackgroundColor: scaffoldBackground ?? colorScheme.background,
      // Card, divider and background colors are same as in ThemeData.from.
      cardColor: colorScheme.surface,
      dividerColor: dividerColor,
      backgroundColor: colorScheme.background,
      // Disabled color uses a different style when using themed interaction
      // effects, if not opted in same as before v4.0.0, use ThemeData default.
      disabledColor: themedEffects
          ? colorScheme.primary
              .blendAlpha(colorScheme.onSurface, kDisabledAlphaBlend)
              .withAlpha(kDisabledBackgroundAlpha)
          : isDark
              ? Colors.white38
              : Colors.black38,

      // Same as ThemeData SDK.
      // hintColor is only used by DropdownButton and InputDecorator in SDK.
      hintColor: isDark ? Colors.white60 : Colors.black.withAlpha(0x99), // 60%
      // TODO(rydmike): Monitor Flutter SDK deprecation of interaction colors.
      // See: https://github.com/flutter/flutter/issues/91772
      // Special theming on hover, focus, highlight and splash, if opting in on
      // themedEffects, otherwise use ThemeData defaults by passing in null
      // and letting it assign its values.
      hoverColor: themedEffects
          ? colorScheme.primary
              .blendAlpha(Colors.white, kHoverAlphaBlend)
              .withAlpha(kHoverAlpha)
          : null,
      focusColor: themedEffects
          ? colorScheme.primary
              .blendAlpha(Colors.white, kFocusAlphaBlend)
              .withAlpha(kFocusAlpha)
          : null,
      highlightColor: themedEffects
          ? colorScheme.primary
              .blendAlpha(Colors.white, kHighlightAlphaBlend)
              .withAlpha(kHighlightAlpha)
          : null,
      splashColor: themedEffects
          ? colorScheme.primary
              .blendAlpha(Colors.white, kSplashAlphaBlend)
              .withAlpha(kSplashAlpha)
          : null,
      // TODO(rydmike): Monitor Flutter SDK deprecation of dialogBackgroundColor
      // Flutter standard dialogBackgroundColor for color scheme based themes
      // uses colorScheme.background.
      // The FlexColorScheme.from() factory constructor uses passed in dialog
      // background color that is same as surface color if not defined, but
      // may also be any other other color.
      // If using surface blends that are not equal for all Material surface
      // backgrounds colors. There will be no elevation overlay color in dark
      // mode, even if so configured.
      // Use dialogs with background color that equals theme
      // colorScheme.surface to ensure it gets elevation overlay color applied
      // in dark mode. See : https://github.com/flutter/flutter/issues/90353
      // The dialogBackgroundColor in ThemeData is going to be deprecated.
      dialogBackgroundColor: dialogBackground ?? colorScheme.surface,
      // Define errorColor via color scheme error color.
      errorColor: colorScheme.error,
      // TODO(rydmike): Monitor Flutter SDK deprecation of indicatorColor.
      // Use TabBar style dependent function for selected Tab as indicatorColor
      // if no color scheme selection for it is made.
      indicatorColor: subTheme.tabBarIndicatorSchemeColor == null
          ? selectedTabColor()
          : FlexSubThemes.schemeColor(
              subTheme.tabBarIndicatorSchemeColor!, colorScheme),
      // Elevation overlay on dark material elevation is used on dark themes
      // on surfaces when so requested, applyElevationOverlayColor defaults
      // to true in FlexColorScheme themes, but you can turn it off.
      // Flutter ThemeData.from ColorScheme based
      // themes also uses this by default, but older ThemeData factories do not.
      applyElevationOverlayColor: isDark && applyElevationOverlayColor,
      // Pass the from FlexColorScheme defined colorScheme to ThemeData
      // colorScheme. Newer standard Flutter sub themes use the colorScheme
      // for their theming, and all sub themes will eventually be converted to
      // be based on the defined color scheme colors. FlexColorScheme passes
      // the scheme it has created to the colorScheme property in ThemeData.
      // More info here: https://flutter.dev/go/material-theme-system-updates
      colorScheme: colorScheme,

      // ----------------------------------------------------------------------
      // The theme settings below are corrective additions to the Flutter
      // standard Theme.from(colorScheme) factory. They are needed because it
      // omits some definitions that will not be aligned with the ColorScheme
      // theme if they are not added to it manually.
      //
      // This document relates to the on going transition:
      // https://flutter.dev/go/material-theme-system-updates
      // This issue explains and demos some of the current gaps:
      // https://github.com/flutter/flutter/issues/65782
      // Some of the gaps will probably be solved as Flutter's theme
      // migration progresses. We monitor the development and will remove no
      // longer needed corrections or remove totally deprecated
      // ThemeData properties when it is appropriate and timely to do so.
      // ----------------------------------------------------------------------
      // TODO(rydmike): Monitor Flutter SDK deprecation of toggleableActive.
      // See: https://github.com/flutter/flutter/pull/95870
      // This color is still important, if it is not set we get a teal color for
      // it in dark mode, and not actually the secondary color that we want for
      // our color scheme based theme. The Flutter color scheme based theme
      // does not include this, in our opinion for correct application of the
      // color scheme based theme, it should really do the same as below.
      // See issue: https://github.com/flutter/flutter/issues/65782
      // When using sub-themes, or Material 3 style, we use primary color
      // instead, because it is the best match for M3 ColorDesign for the M2
      // components using M3 Colors.
      toggleableActiveColor: useSubThemes || useMaterial3
          ? colorScheme.primary
          : colorScheme.secondary,
      // TODO(rydmike): Monitor Flutter SDK deprecation of primaryColorDark.
      // See: https://github.com/flutter/flutter/issues/91772
      // The primary dark color no longer exists in ColorScheme themes, but
      // it still needs to be set to match the ColorScheme theme, otherwise we
      // get a default dark blue theme color for it coming from default
      // primarySwatch. This will not look good if your theme uses any primary
      // color that is not a blue hue. To fix this we use the [700] value from
      // the calculated primary swatch for dark mode and [800] for light mode.
      // This property is used by `CircleAvatar` and `Slider`.
      // See issue: https://github.com/flutter/flutter/issues/65782
      primaryColorDark: primaryColorDark,
      // TODO(rydmike): Monitor Flutter SDK deprecation of primaryColorLight.
      // See: https://github.com/flutter/flutter/issues/91772
      // The light primary color no longer exists in ColorScheme themes, but it
      // still needs to be set to match the ColorScheme theme, otherwise we
      // get a default blue color for it coming from the default primarySwatch.
      // We use the [100] value from the calculated primary swatch.
      // This property is used by `CircleAvatar` and `Slider`.
      // See issue: https://github.com/flutter/flutter/issues/65782
      primaryColorLight: primaryColorLight,
      // TODO(rydmike): Monitor Flutter SDK deprecation of secondaryHeaderColor
      // See: https://github.com/flutter/flutter/issues/91772
      // Define a secondary header color, this property is only used in Flutter
      // SDK by `PaginatedDataTable`. It gets a super light [50] hue of the
      // primary color from default theme.light factory. Here we use the [50]
      // value from the calculated primary swatch.
      // See issue: https://github.com/flutter/flutter/issues/65782
      secondaryHeaderColor: secondaryHeaderColor,
      // TODO(rydmike): Tech debt: Move AppBar theme opt-in to FlexSubThemes.
      // The app bar theme allows us to use a custom colored appbar theme
      // in both light and dark themes that is not dependent on theme primary
      // or surface color, and still gets a correct working text and icon theme.
      // In the versions prior to Flutter 2.0.0 doing this was very difficult,
      // as presented in https://github.com/flutter/flutter/issues/50606 doing
      // this was a tricky. A new feature in Flutter 2.0.0 implemented via:
      // https://github.com/flutter/flutter/pull/71184 makes this setup easy.
      // The FlexColorScheme implementation below has been changed to
      // use these new AppBarTheme features in version 2.0.0.
      appBarTheme: AppBarTheme(
        backgroundColor: effectiveAppBarColor,
        foregroundColor: appBarForeground,
        iconTheme: IconThemeData(color: appBarIconColor),
        actionsIconTheme: IconThemeData(color: appBarIconColor),
        elevation: appBarElevation,
        systemOverlayStyle: SystemUiOverlayStyle(
          systemStatusBarContrastEnforced: false,
          // AppBar overlay style.
          statusBarColor: transparentStatusBar
              ? Colors.transparent
              // This is the actual scrim color used by Android by default,
              // here we just re-apply if false or if it had been removed
              // earlier, using `null` does not restore it, we need to re-apply
              // the used scrim color by Android to restore if it has been
              // removed earlier.
              : const Color(0x40000000),
          statusBarBrightness: appBarBrightness,
          statusBarIconBrightness: appBarBrightness == Brightness.dark
              ? Brightness.light
              : Brightness.dark,
          // TODO(rydmike): Raise sys-nav AppBar systemOverlayStyle SDK issue.
          //   Would be useful it could set system navbar properties too and not
          //   only status bar properties. While it might be odd to do so, it
          //   seems even more odd that a part of the SystemUiOverlayStyle has
          //   no effect when used here.
          // The systemNavigationBarColor used by default AppBar in SDK is
          // always black, like so:
          // systemNavigationBarColor: const Color(0xFF000000),
          // We try to set it to scheme background instead in AppBar theme,
          // does not do anything, result will be black anyway.
          systemNavigationBarColor: colorScheme.background,
          // The systemNavigationBarIconBrightness used by the AppBar in SDK, is
          // always light, for the black background it get, like so:
          // systemNavigationBarIconBrightness: Brightness.light,
          // We try to match it to the color of our scheme background, but we
          // always get the light ones anyway, which is fine, as long as the
          // system navbar remains black anyway.
          systemNavigationBarIconBrightness:
              isDark ? Brightness.light : Brightness.dark,
          // Keeping the above system navbar changes, even if they up to at
          // least Flutter 2.10.3 did not do anything, maybe they start to
          // work one day, then we do not not need an AnnotatedRegion for it
          // anymore but can get it via AppBar theme, the way it should work.
          // The systemNavigationBarDividerColor used by default AppBar in SDK:
          systemNavigationBarDividerColor: null,
          systemNavigationBarContrastEnforced: false,
        ),
      ),

      // The bottom app bar uses color scheme background color to match the
      // background color of the drawer, bottom navigation bar, possible side
      // menu and system navigation bar on android (if theming of it is used).
      // This is a slight change from the ColorScheme default that uses
      // surface color.
      bottomAppBarColor: colorScheme.background,
      bottomAppBarTheme: BottomAppBarTheme(
        color: colorScheme.background,
        elevation: bottomAppBarElevation,
      ),
      // In TextSelectionThemeData, the standard for selectionColor is
      // colorScheme.primary with opacity value 0.4 for dark and 0.12 light
      // mode. Here we use primary with 0.5 for dark mode and 0.3 for light
      // mode. The standard selectionHandleColor is colorScheme.primary,
      // here we use the slightly darker shade primaryColorDark instead.
      textSelectionTheme: TextSelectionThemeData(
        selectionColor: isDark
            ? colorScheme.primary.withAlpha(0xB2) // 50%
            : colorScheme.primary.withAlpha(0x4C), // 30%
        selectionHandleColor: primaryColorDark,
      ),
      // TODO(rydmike): Tech debt: Move TabBar theme opt-in to a FlexSubThemes.
      // Defines the TabBar theme that will fit nicely in an AppBar
      // (default) or on background color for use eg in a Scaffold, the choice
      // depends on tabBarStyle `FlexTabBarStyle`, that defaults to
      // `FlexTabBarStyle.forAppBar`. Using different theme styles for intended
      // target usage avoids this challenge:
      // https://github.com/flutter/flutter/pull/68171#pullrequestreview-517753917
      // That still has some issue related to it, is using default is used, we
      // pass in `null` and let ThemeData use default sub-theme for TabBarTheme.
      tabBarTheme: TabBarTheme(
          indicatorSize: TabBarIndicatorSize.tab,
          labelStyle: effectiveTextTheme.bodyText1,
          labelColor: subTheme.tabBarItemSchemeColor == null
              ? selectedTabColor()
              : FlexSubThemes.schemeColor(
                  subTheme.tabBarItemSchemeColor!, colorScheme),
          unselectedLabelStyle: effectiveTextTheme.bodyText1,
          unselectedLabelColor: subTheme.tabBarItemSchemeColor == null
              ? unselectedTabColor()
              : FlexSubThemes.schemeColor(
                      subTheme.tabBarItemSchemeColor!, colorScheme)
                  .withAlpha(0x99) // 60%,
          ),
      // Set colors for for icons in opted in sub themes.
      iconTheme: useSubThemes
          ? IconThemeData(color: effectiveTextTheme.headline6!.color)
          : null,
      primaryIconTheme: useSubThemes
          ? IconThemeData(color: effectivePrimaryTextTheme.headline6!.color)
          : null,
      // TODO(rydmike): Tech debt: Move tooltip theme opt-in to FlexSubThemes.
      // TODO(rydmike): Offer more tooltip theming options, like tip delays.
      // Opinionated theming of Tooltips, the default theme for Material
      // themed Tooltips are not ideal design choices on desktop and web
      // https://material.io/components/tooltips#specs.
      // The theming below is an opinionated alternative design, with an option
      // to also invert the tooltip background color.
      // See issue: https://github.com/flutter/flutter/issues/71429
      tooltipTheme: TooltipThemeData(
        // Do not use the min height, the custom padding handles it instead.
        padding: tooltipPadding(),
        margin: const EdgeInsets.symmetric(horizontal: 12, vertical: 6),
        textStyle: effectiveTextTheme.bodyText2!.copyWith(
          inherit: false,
          color: tooltipsMatchBackground
              ? isDark
                  ? Colors.white
                  : Colors.black
              : isDark
                  ? Colors.black
                  : Colors.white,
          fontSize: tooltipFontSize(),
        ),
        decoration: useSubThemes
            // Opted in on sub-themes, we make a more fitting tooltip too.
            ? tooltipsMatchBackground
                ? BoxDecoration(
                    color: isDark
                        ? FlexColor.darkSurface
                            .blendAlpha(colorScheme.primary, 0x28) // 16%
                            .withAlpha(0xF2) // 95%
                        : FlexColor.lightSurface
                            .blendAlpha(colorScheme.primary, 0x0A) // 4%
                            .withAlpha(0xF2), // 95%
                    borderRadius: const BorderRadius.all(Radius.circular(8)),
                    border: Border.all(color: dividerColor),
                  )
                : BoxDecoration(
                    color: isDark
                        ? FlexColor.lightSurface
                            .blendAlpha(colorScheme.primary, 0x63) // 39%
                            .withAlpha(0xF2) // 95%
                        : FlexColor.darkSurface
                            .blendAlpha(colorScheme.primary, 0x72) // 45%
                            .withAlpha(0xF2), // 95%
                    borderRadius: const BorderRadius.all(Radius.circular(8)),
                    border: Border.all(color: dividerColor),
                  )
            // Not opted in on sub themes, use the before v4 style.
            : tooltipsMatchBackground
                ? BoxDecoration(
                    color: isDark
                        ? const Color(0xED444444)
                        : const Color(0xF0FCFCFC),
                    borderRadius: const BorderRadius.all(Radius.circular(4)),
                    border: Border.all(color: dividerColor),
                  )
                : null,
      ),
      textButtonTheme: useSubThemes
          ? FlexSubThemes.textButtonTheme(
              colorScheme: colorScheme,
              baseSchemeColor: subTheme.textButtonSchemeColor,
              radius: subTheme.textButtonRadius ?? subTheme.defaultRadius,
              padding: subTheme.buttonPadding,
              minButtonSize: subTheme.buttonMinSize,
            )
          : null,
      elevatedButtonTheme: useSubThemes
          ? FlexSubThemes.elevatedButtonTheme(
              colorScheme: colorScheme,
              baseSchemeColor: subTheme.elevatedButtonSchemeColor,
              radius: subTheme.elevatedButtonRadius ?? subTheme.defaultRadius,
              elevation: subTheme.elevatedButtonElevation,
              padding: subTheme.buttonPadding,
              minButtonSize: subTheme.buttonMinSize,
            )
          : null,
      outlinedButtonTheme: useSubThemes
          ? FlexSubThemes.outlinedButtonTheme(
              colorScheme: colorScheme,
              baseSchemeColor: subTheme.outlinedButtonSchemeColor,
              radius: subTheme.outlinedButtonRadius ?? subTheme.defaultRadius,
              pressedOutlineWidth: subTheme.thickBorderWidth,
              outlineWidth: subTheme.thinBorderWidth,
              padding: subTheme.buttonPadding,
              minButtonSize: subTheme.buttonMinSize,
            )
          : null,
      // Since the old buttons have been deprecated in Flutter 2.0.0
      // they are no longer presented or used in the code in FlexColorScheme.
      // The button theming below still makes the old buttons almost
      // look like the defaults for the new ElevatedButton, TextButton and
      // OutlinedButton.
      // This buttonTheme setup, makes the old legacy Material buttons
      // [RaisedButton], [OutlineButton] and [FlatButton] very similar in
      // style to the default color scheme based style used for the
      // newer Material buttons [ElevatedButton], [OutlinedButton] and
      // [TextButton]. There are some differences in margin
      // and outline color and the elevation behavior on the raised button.
      // A useSubThemes was added in version 4.0.0 to also still support
      // the old buttons.
      // The legacy buttons will be completely removed in Flutter stable
      // version after 2.10.x. The [ButtonThemeData] this helper uses will
      // however remain available after that, because widgets
      // [ButtonBar] and [DropdownButton], plus [MaterialButton] (marked as
      // obsolete in SDK docs though) still use this theme. It is thus kept
      // around in FlexColorScheme package as long as it might have some use.
      // Be aware that the buttonTheme will be removed from
      // FlexColorScheme when/if ButtonThemeData becomes deprecated Flutter SDK.
      buttonTheme: useSubThemes
          ? FlexSubThemes.buttonTheme(
              colorScheme: colorScheme,
              baseSchemeColor: subTheme.materialButtonSchemeColor,
              radius: subTheme.textButtonRadius ?? subTheme.defaultRadius,
              padding: subTheme.buttonPadding,
              minButtonSize: subTheme.buttonMinSize,
            )
          : ButtonThemeData(
              colorScheme: colorScheme,
              textTheme: ButtonTextTheme.primary,
              materialTapTargetSize: MaterialTapTargetSize.shrinkWrap,
              padding: const EdgeInsets.symmetric(horizontal: 16),
            ),
      // Toggle buttons have limited theming capability and cannot match new
      // buttons fully, this is an approximation.
      toggleButtonsTheme: useSubThemes
          ? FlexSubThemes.toggleButtonsTheme(
              colorScheme: colorScheme,
              baseSchemeColor: subTheme.toggleButtonsSchemeColor,
              borderWidth: subTheme.thinBorderWidth,
              radius: subTheme.toggleButtonsRadius ?? subTheme.defaultRadius,
              minButtonSize: subTheme.buttonMinSize,
              visualDensity: visualDensity,
            )
          : null,
      // Switch theme.
      switchTheme: useSubThemes
          ? FlexSubThemes.switchTheme(
              colorScheme: colorScheme,
              baseSchemeColor: subTheme.switchSchemeColor,
              unselectedIsColored: subTheme.unselectedToggleIsColored,
            )
          : null,
      // Checkbox theme.
      checkboxTheme: useSubThemes
          ? FlexSubThemes.checkboxTheme(
              colorScheme: colorScheme,
              baseSchemeColor: subTheme.checkboxSchemeColor,
              unselectedIsColored: subTheme.unselectedToggleIsColored,
            )
          : null,
      // Radio theme.
      radioTheme: useSubThemes
          ? FlexSubThemes.radioTheme(
              colorScheme: colorScheme,
              baseSchemeColor: subTheme.radioSchemeColor,
              unselectedIsColored: subTheme.unselectedToggleIsColored,
            )
          : null,
      // Input decorator theme.
      inputDecorationTheme: effectiveInputDecorationTheme,
      // FAB, floating action button theme.
      floatingActionButtonTheme: useSubThemes
          ? FlexSubThemes.floatingActionButtonTheme(
              colorScheme: colorScheme,
              backgroundSchemeColor: subTheme.fabSchemeColor,
              radius: subTheme.fabRadius ?? subTheme.defaultRadius,
              useShape: subTheme.fabUseShape,
            )
          : null,
      // The default chip theme in Flutter does not work correctly with dark
      // themes. See issue: https://github.com/flutter/flutter/issues/65663
      // The chip theme below fixes it by using the colorScheme.primary color.
      // The option when useSubThemes is true uses even more elaborate theming
      // of chips. It is possible that there will be new Chips entirely for
      // Material 3. This theme brings the look closer to M3 look, but cannot
      // reach all the way.
      chipTheme: useSubThemes
          ? FlexSubThemes.chipTheme(
              colorScheme: colorScheme,
              baseSchemeColor: subTheme.chipSchemeColor,
              labelStyle: effectiveTextTheme.button!,
              radius: subTheme.chipRadius ?? subTheme.defaultRadius,
            )
          : ChipThemeData.fromDefaults(
              secondaryColor: colorScheme.primary,
              brightness: colorScheme.brightness,
              labelStyle: effectiveTextTheme.bodyText1!,
            ),
      cardTheme: useSubThemes
          ? FlexSubThemes.cardTheme(
              radius: subTheme.cardRadius ?? subTheme.defaultRadius,
              elevation: subTheme.cardElevation,
            )
          : null,
      popupMenuTheme: useSubThemes
          ? FlexSubThemes.popupMenuTheme(
              radius: subTheme.popupMenuRadius ??
                  (subTheme.defaultRadius == null
                      ? null
                      : math.min(subTheme.defaultRadius!, 10.0)),
              elevation: subTheme.popupMenuElevation,
              color: subTheme.popupMenuOpacity == null
                  ? null
                  : colorScheme.surface.withOpacity(subTheme.popupMenuOpacity!),
            )
          : null,
      dialogTheme: useSubThemes
          ? FlexSubThemes.dialogTheme(
              backgroundColor: dialogBackground,
              colorScheme: colorScheme,
              backgroundSchemeColor: subTheme.dialogBackgroundSchemeColor,
              radius: subTheme.dialogRadius ?? subTheme.defaultRadius,
              elevation: subTheme.dialogElevation,
            )
          : null,
      timePickerTheme: useSubThemes
          ? FlexSubThemes.timePickerTheme(
              backgroundColor: dialogBackground,
              colorScheme: colorScheme,
              backgroundSchemeColor: subTheme.dialogBackgroundSchemeColor,
              radius: subTheme.timePickerDialogRadius ?? subTheme.defaultRadius,
              elementRadius: subTheme.cardRadius ?? subTheme.defaultRadius,
              inputDecorationTheme: effectiveInputDecorationTheme)
          : null,
      snackBarTheme: useSubThemes
          ? FlexSubThemes.snackBarTheme(
              elevation: subTheme.snackBarElevation,
              colorScheme: colorScheme,
              backgroundSchemeColor: subTheme.snackBarBackgroundSchemeColor,
              backgroundColor: isDark
                  ? colorScheme.onSurface
                      .blendAlpha(colorScheme.primary, 0x63) // 39%
                      .withAlpha(0xF2) // 95%
                  : colorScheme.onSurface
                      .blendAlpha(colorScheme.primary, 0x72) // 45%
                      .withAlpha(0xED) // 93%
              )
          : null,
      bottomSheetTheme: useSubThemes
          ? FlexSubThemes.bottomSheetTheme(
              radius: subTheme.bottomSheetRadius ?? subTheme.defaultRadius,
              elevation: subTheme.bottomSheetElevation,
              modalElevation: subTheme.bottomSheetModalElevation,
            )
          : null,
      // Opinionated default theming for the bottom navigation bar: Use primary
      // color for selected item. Flutter defaults to using secondary color in
      // dark mode, we want primary in dark mode too, like it is in light
      // mode. Primary color is an iOS influenced style for the bottom nav.
      // Above was default in version < 4, version 4 can also use sub-theme.
      bottomNavigationBarTheme: useSubThemes
          ? FlexSubThemes.bottomNavigationBar(
              colorScheme: colorScheme,
              labelTextStyle: subTheme.bottomNavigationBarLabelTextStyle ??
                  (subTheme.useFlutterDefaults
                      ? null
                      : effectiveTextTheme.bodyMedium),
              selectedLabelSize: subTheme.bottomNavigationBarSelectedLabelSize,
              unselectedLabelSize:
                  subTheme.bottomNavigationBarUnselectedLabelSize,
              selectedLabelSchemeColor:
                  subTheme.bottomNavigationBarSelectedLabelSchemeColor,
              unselectedLabelSchemeColor:
                  subTheme.bottomNavigationBarUnselectedLabelSchemeColor,
              mutedUnselectedLabel:
                  subTheme.bottomNavigationBarMutedUnselectedLabel,
              selectedIconSize: subTheme.bottomNavigationBarSelectedIconSize,
              unselectedIconSize:
                  subTheme.bottomNavigationBarUnselectedIconSize,
              selectedIconSchemeColor:
                  subTheme.bottomNavigationBarSelectedIconSchemeColor,
              unselectedIconSchemeColor:
                  subTheme.bottomNavigationBarUnselectedIconSchemeColor,
              mutedUnselectedIcon:
                  subTheme.bottomNavigationBarMutedUnselectedIcon,
              backgroundSchemeColor:
                  subTheme.bottomNavigationBarBackgroundSchemeColor,
              opacity: subTheme.bottomNavigationBarOpacity,
              elevation: subTheme.bottomNavigationBarElevation,
              type: subTheme.bottomNavigationBarType,
              showSelectedLabels:
                  subTheme.bottomNavigationBarShowSelectedLabels,
              showUnselectedLabels:
                  subTheme.bottomNavigationBarShowUnselectedLabels,
              landscapeLayout: subTheme.bottomNavigationBarLandscapeLayout,
              unselectedAlphaBlend: kUnselectedBackgroundPrimaryAlphaBlend,
              unselectedAlpha: kUnselectedAlphaBlend,
              useFlutterDefaults: subTheme.useFlutterDefaults,
            )
          : BottomNavigationBarThemeData(
              selectedIconTheme: IconThemeData(
                color: colorScheme.primary,
              ),
              selectedItemColor: colorScheme.primary,
            ),
      // Opinionated sub theme for Material 3 based Navigation Bar
      navigationBarTheme: useSubThemes
          ? FlexSubThemes.navigationBarTheme(
              colorScheme: colorScheme,
              labelTextStyle: subTheme.navigationBarLabelTextStyle ??
                  (subTheme.useFlutterDefaults
                      ? null
                      : effectiveTextTheme.labelMedium),
              selectedLabelSize: subTheme.navigationBarSelectedLabelSize,
              unselectedLabelSize: subTheme.navigationBarUnselectedLabelSize,
              selectedLabelSchemeColor:
                  subTheme.navigationBarSelectedLabelSchemeColor,
              unselectedLabelSchemeColor:
                  subTheme.navigationBarUnselectedLabelSchemeColor,
              mutedUnselectedLabel: subTheme.navigationBarMutedUnselectedLabel,
              selectedIconSize: subTheme.navigationBarSelectedIconSize,
              unselectedIconSize: subTheme.navigationBarUnselectedIconSize,
              selectedIconSchemeColor:
                  subTheme.navigationBarSelectedIconSchemeColor,
              unselectedIconSchemeColor:
                  subTheme.navigationBarUnselectedIconSchemeColor,
              mutedUnselectedIcon: subTheme.navigationBarMutedUnselectedIcon,
              indicatorSchemeColor: subTheme.navigationBarIndicatorSchemeColor,
              backgroundSchemeColor:
                  subTheme.navigationBarBackgroundSchemeColor,
              opacity: subTheme.navigationBarOpacity,
              height: subTheme.navigationBarHeight,
              labelBehavior: subTheme.navigationBarLabelBehavior,
              indicatorAlpha: subTheme.navigationBarIndicatorOpacity != null
                  ? Color.getAlphaFromOpacity(
                      subTheme.navigationBarIndicatorOpacity!)
                  : null,
              unselectedAlphaBlend: kUnselectedBackgroundPrimaryAlphaBlend,
              unselectedAlpha: kUnselectedAlphaBlend,
              useMaterial3: useMaterial3,
              useFlutterDefaults: subTheme.useFlutterDefaults,
            )
          : null,
      // Opinionated sub theme for Material 3 based Navigation Bar
      navigationRailTheme: useSubThemes
          ? FlexSubThemes.navigationRailTheme(
              colorScheme: colorScheme,
              labelTextStyle: subTheme.navigationRailLabelTextStyle ??
                  (subTheme.useFlutterDefaults
                      ? null
                      : effectiveTextTheme.labelMedium),
              selectedLabelSize: subTheme.navigationRailSelectedLabelSize,
              unselectedLabelSize: subTheme.navigationRailUnselectedLabelSize,
              selectedLabelSchemeColor:
                  subTheme.navigationRailSelectedLabelSchemeColor,
              unselectedLabelSchemeColor:
                  subTheme.navigationRailUnselectedLabelSchemeColor,
              mutedUnselectedLabel: subTheme.navigationRailMutedUnselectedLabel,
              selectedIconSize: subTheme.navigationRailSelectedIconSize,
              unselectedIconSize: subTheme.navigationRailUnselectedIconSize,
              selectedIconSchemeColor:
                  subTheme.navigationRailSelectedIconSchemeColor,
              unselectedIconSchemeColor:
                  subTheme.navigationRailUnselectedIconSchemeColor,
              mutedUnselectedIcon: subTheme.navigationRailMutedUnselectedIcon,
              useIndicator: subTheme.navigationRailUseIndicator,
              indicatorSchemeColor: subTheme.navigationRailIndicatorSchemeColor,
              backgroundSchemeColor:
                  subTheme.navigationRailBackgroundSchemeColor,
              opacity: subTheme.navigationRailOpacity,
              elevation: subTheme.navigationRailElevation,
              labelType: subTheme.navigationRailLabelType,
              groupAlignment: subTheme.navigationRailGroupAlignment,
              indicatorAlpha: subTheme.navigationRailIndicatorOpacity != null
                  ? Color.getAlphaFromOpacity(
                      subTheme.navigationRailIndicatorOpacity!)
                  : null,
              unselectedAlphaBlend: kUnselectedBackgroundPrimaryAlphaBlend,
              unselectedAlpha: kUnselectedAlphaBlend,
              useMaterial3: useMaterial3,
              useFlutterDefaults: subTheme.useFlutterDefaults,
            )
          : null,
    );
  }

  /// Returns the effective [ColorScheme] defined by your [FlexColorScheme].
  ///
  /// After you have defined your Flex scheme with [FlexColorScheme] or one of
  /// its recommended factories [FlexColorScheme.light], [FlexColorScheme.dark],
  /// you can use the [toScheme] method to get the effective standard Flutter
  /// [ColorScheme] object defined by your [FlexColorScheme] definition.
  ///
  /// While you can use use this returned color scheme in a standard
  /// [ThemeData.from] color scheme based theme factory to create a theme from
  /// [FlexColorScheme], this is NOT the recommended way to make a
  /// fully [FlexColorScheme] based theme. Normally you want to use
  /// [FlexColorScheme.toTheme] to make your ThemeData when using
  /// FlexColorScheme. The [FlexColorScheme.toTheme] method uses
  /// [FlexColorScheme.toScheme] internally when it creates its [ThemeData]
  /// object as well. It does however also apply a number of additional
  /// theme properties, that you loose if you extract the [ColorScheme]
  /// with [toScheme] and use it in a [ThemeData.from] from factory.
  ///
  /// The main usage of this method is to get the effective resulting
  /// [ColorScheme] from [FlexColorScheme] and use it when making sub-themes
  /// that need access to the resulting color definitions, so you can use
  /// them in custom sub-themes in order to use the same color scheme for their
  /// definitions.
  ///
  /// If you use [ThemeData.from] and the [ColorScheme] returned by
  /// [FlexColorScheme.toScheme] to create your theme, this will work and
  /// result in a theme that is based on the color scheme defined in
  /// [FlexColorScheme], including the surface and
  /// background color branding, and e.g. true black for dark mode, if those
  /// were used in its creation via the light and dark factories. The big
  /// difference will be that Flutter's [ThemeData.from] theme creation
  /// from this scheme will not include any of the theme improvements included
  /// in the [FlexColorScheme.toTheme] method. The AppBar theme options
  /// will also not be available and scaffoldBackground
  /// will be equal to background, which might not be the design you intended.
  ///
  /// The sub-theming is of course also not available, unless you apply them
  /// all with `copyWith` to the produced ThemeData.
  ColorScheme get toScheme {
    // Get effective scheme brightness. Passed in as a property value, or from
    // passed in colorScheme, if neither given, light is default fallback.
    final Brightness usedBrightness =
        brightness ?? colorScheme?.brightness ?? Brightness.light;
    final bool isDark = usedBrightness == Brightness.dark;
    // Get effective primary color. Passed in a as property, if not, then maybe
    // from colorScheme, if neither given, fallback color is light or dark mode
    // Material 2 guide default light and dark primary color.
    final Color usedPrimary = primary ??
        colorScheme?.primary ??
        (isDark
            ? FlexColor.materialDarkPrimary
            : FlexColor.materialLightPrimary);

    // Get default fallback error color.
    final Color errorFallback =
        isDark ? FlexColor.materialDarkError : FlexColor.materialLightError;
    final Color errorContainerFallback = isDark
        ? FlexColor.darkErrorContainer(FlexColor.materialDarkError)
        : FlexColor.lightErrorContainer(FlexColor.materialLightError);

    // Determine effective primary, secondary and tertiary colors, depending
    // on passed in properties as highest priority, then colorScheme values.
    // Containers fall back via none container values, tertiary via secondary.
    // All falls back to primary, if nothing else is available before that.
    final FlexSchemeColor colors = FlexSchemeColor.from(
      primary: usedPrimary,
      // TODO(rydmike): Remove backwards compatibility behavior in v6.0.0.
      //   The fallthrough via internally deprecated primaryVariant is for
      //   backwards compatibility with FlexColorScheme before version 5.
      primaryContainer: primaryContainer ??
          primaryVariant ??
          colorScheme?.primaryContainer ??
          usedPrimary,
      secondary: secondary ?? colorScheme?.secondary ?? usedPrimary,
      // TODO(rydmike): Remove backwards compatibility behavior in v6.0.0.
      //   The fallthrough via internally deprecated primaryVariant is for
      //   backwards compatibility with FlexColorScheme before version 5.
      secondaryContainer: secondaryContainer ??
          secondaryVariant ??
          colorScheme?.secondaryContainer ??
          secondary ??
          colorScheme?.secondary ??
          usedPrimary,
      tertiary: tertiary ??
          colorScheme?.tertiary ??
          secondary ??
          colorScheme?.secondary ??
          usedPrimary,
      tertiaryContainer: tertiaryContainer ??
          colorScheme?.tertiaryContainer ??
          tertiary ??
          colorScheme?.tertiary ??
          secondary ??
          colorScheme?.secondary ??
          usedPrimary,
      error: error ?? colorScheme?.error ?? errorFallback,
      errorContainer: colorScheme?.errorContainer ?? errorContainerFallback,
    );
    // Determine effective surface surface and background.
    final Color effectiveSurfaceColor = surface ??
        colorScheme?.surface ??
        (isDark
            ? FlexColor.materialDarkSurface
            : FlexColor.materialLightSurface);
    final Color effectiveSurfaceVariantColor = colorScheme?.surfaceVariant ??
        (isDark
            ? FlexColor.materialDarkSurface
            : FlexColor.materialLightSurface);

    final Color effectiveInverseSurfaceColor = colorScheme?.inverseSurface ??
        (isDark
            ? FlexColor.materialLightSurface
            : FlexColor.materialDarkSurface);

    final Color effectiveBackgroundColor = background ??
        colorScheme?.background ??
        (isDark
            ? FlexColor.materialDarkBackground
            : FlexColor.materialLightBackground);

    // Check brightness of primary, secondary, error, surface and background
    // colors, and returns appropriate computed colors for their onColors if an
    // onColor for it was was not passed in, or no colorScheme with them were
    // passed in. If they were, the passed in direct values have highest
    // priority, then the values in a given colorScheme, and lastly a value
    // computed from its main color pair is used.
    final FlexSchemeOnColors onColors = FlexSchemeOnColors.from(
      primary: colors.primary,
      primaryContainer: colors.primaryContainer,
      secondary: colors.secondary,
      secondaryContainer: colors.secondaryContainer,
      tertiary: colors.tertiary,
      tertiaryContainer: colors.tertiaryContainer,
      surface: effectiveSurfaceColor,
      surfaceVariant: effectiveSurfaceVariantColor,
      inverseSurface: effectiveInverseSurfaceColor,
      background: effectiveBackgroundColor,
      error: colors.error ?? errorFallback,
      errorContainer: colors.errorContainer ?? errorContainerFallback,
      onPrimary: onPrimary ?? colorScheme?.onPrimary,
      onPrimaryContainer: onPrimaryContainer ?? colorScheme?.onPrimaryContainer,
      onSecondary: onSecondary ?? colorScheme?.onSecondary,
      onSecondaryContainer:
          onSecondaryContainer ?? colorScheme?.onSecondaryContainer,
      onTertiary: onTertiary ?? colorScheme?.onTertiary,
      onTertiaryContainer:
          onTertiaryContainer ?? colorScheme?.onTertiaryContainer,
      onSurface: onSurface ?? colorScheme?.onSurface,
      onSurfaceVariant: colorScheme?.onSurfaceVariant,
      onInverseSurface: colorScheme?.onInverseSurface,
      onBackground: onBackground ?? colorScheme?.onBackground,
      onError: onError ?? colorScheme?.onError,
      onErrorContainer: colorScheme?.onErrorContainer,
    );
    // Return the ColorScheme as a copyWith on original passed in colorScheme
    // if one was passed in, with all the effective properties overriding its
    // corresponding properties. This will keep color properties not included in
    // FlexColorScheme as direct properties as they were in any given
    // colorScheme, in the returned ColorScheme as well.
    // If there was no colorScheme passed in, we create one with the effective
    // override properties, plus FlexColorScheme ColorScheme defaults.
    //
    // The factories FlexColorScheme.light and FlexColorScheme.dark have their
    // own logic for making the ColorScheme and set a colorScheme as well as
    // all override properties to define their target ColorScheme when the
    // toScheme methods is called.
    //
    // The toScheme method is used internally by the toTheme method to get
    // the effective ColorScheme for the the defined FlexColorScheme instance.
    return colorScheme?.copyWith(
          brightness: usedBrightness,
          primary: colors.primary,
          onPrimary: onColors.onPrimary,
          primaryContainer: colors.primaryContainer,
          onPrimaryContainer: onColors.onPrimaryContainer,
          secondary: colors.secondary,
          onSecondary: onColors.onSecondary,
          secondaryContainer: colors.secondaryContainer,
          onSecondaryContainer: onColors.onSecondaryContainer,
          tertiary: colors.tertiary,
          onTertiary: onColors.onTertiary,
          tertiaryContainer: colors.tertiaryContainer,
          onTertiaryContainer: onColors.onTertiaryContainer,
          error: colors.error ?? errorFallback,
          onError: onColors.onError,
          errorContainer: colors.errorContainer ?? errorContainerFallback,
          onErrorContainer: onColors.onErrorContainer,
          background: effectiveBackgroundColor,
          onBackground: onColors.onBackground,
          surface: effectiveSurfaceColor,
          onSurface: onColors.onSurface,
          surfaceVariant: effectiveSurfaceVariantColor,
          onSurfaceVariant: onColors.onSurfaceVariant,
          inverseSurface: effectiveInverseSurfaceColor,
          onInverseSurface: onColors.onInverseSurface,
          inversePrimary: colorScheme?.inversePrimary,
          shadow: colorScheme?.shadow,
          outline: colorScheme?.outline,
          surfaceTint:
              surfaceTint ?? colorScheme?.surfaceTint ?? colors.primary,
        ) ??
        // No passed in ColorScheme, we create one with the effective
        // override properties, plus FlexColorScheme ColorScheme defaults.
        ColorScheme(
          brightness: usedBrightness,
          primary: usedPrimary,
          onPrimary: onColors.onPrimary,
          primaryContainer: colors.primaryContainer,
          onPrimaryContainer: onColors.onPrimaryContainer,
          secondary: colors.secondary,
          onSecondary: onColors.onSecondary,
          secondaryContainer: colors.secondaryContainer,
          onSecondaryContainer: onColors.onSecondaryContainer,
          tertiary: colors.tertiary,
          onTertiary: onColors.onTertiary,
          tertiaryContainer: colors.tertiaryContainer,
          onTertiaryContainer: onColors.onTertiaryContainer,
          error: colors.error ?? errorFallback,
          onError: onColors.onError,
          errorContainer: colors.errorContainer ?? errorContainerFallback,
          onErrorContainer: onColors.onErrorContainer,
          background: effectiveBackgroundColor,
          onBackground: onColors.onBackground,
          surface: effectiveSurfaceColor,
          onSurface: onColors.onSurface,
          surfaceVariant: effectiveSurfaceVariantColor,
          onSurfaceVariant: onColors.onSurfaceVariant,
          inverseSurface: effectiveInverseSurfaceColor,
          onInverseSurface: onColors.onInverseSurface,
          inversePrimary: _inversePrimary(
              usedBrightness, colors.primary, effectiveSurfaceColor),
          shadow: Colors.black,
          outline: _outlineColor(usedBrightness, onColors.onBackground),
          surfaceTint: surfaceTint ?? usedPrimary,
        );
  }

  // TODO(rydmike): Consider improving FCS inversePrimary algorithm.
  /// FlexColorScheme default for inversePrimary color, when not using seeds.
  ///
  /// When using real M3 ColorScheme's that are seeded, this color is not used.
  ///
  /// Not the best algo in the world, but simple and works fairly well for light
  /// Brightness, but should be better for dark.
  static Color _inversePrimary(
      Brightness brightness, Color primary, Color surface) {
    if (brightness == Brightness.light) {
      return primary.brighten(40).lighten(10);
    } else {
      return primary.brighten(5).blendAlpha(surface, 0x99);
    }
  }

  /// FlexColorScheme default for outline color, when not using seeds.
  static Color _outlineColor(Brightness brightness, Color onBackground) {
    if (brightness == Brightness.light) {
      return onBackground.lighten(30);
    } else {
      return onBackground.darken(30);
    }
  }

  /// Copy the object with one or more provided properties changed.
  FlexColorScheme copyWith({
    ColorScheme? colorScheme,
    Brightness? brightness,
    Color? primary,
    Color? primaryContainer,
    Color? primaryVariant,
    Color? secondary,
    Color? secondaryContainer,
    Color? secondaryVariant,
    Color? tertiary,
    Color? tertiaryContainer,
    Color? error,
    Color? surface,
    Color? background,
    Color? scaffoldBackground,
    Color? dialogBackground,
    Color? appBarBackground,
    Color? onPrimary,
    Color? onPrimaryContainer,
    Color? onSecondary,
    Color? onSecondaryContainer,
    Color? onTertiary,
    Color? onTertiaryContainer,
    Color? onSurface,
    Color? onBackground,
    Color? onError,
    Color? surfaceTint,
    FlexTabBarStyle? tabBarStyle,
    double? appBarElevation,
    double? bottomAppBarElevation,
    bool? tooltipsMatchBackground,
    bool? transparentStatusBar,
    VisualDensity? visualDensity,
    TextTheme? textTheme,
    TextTheme? primaryTextTheme,
    String? fontFamily,
    TargetPlatform? platform,
    Typography? typography,
    bool? applyElevationOverlayColor,
    FlexSubThemesData? subThemesData,
    bool? useMaterial3,
    Iterable<ThemeExtension<dynamic>>? extensions,
  }) {
    return FlexColorScheme(
      colorScheme: colorScheme ?? this.colorScheme,
      brightness: brightness ?? this.brightness,
      primary: primary ?? this.primary,
      primaryContainer: primaryContainer ?? this.primaryContainer,
      primaryVariant: primaryVariant ?? this.primaryVariant,
      secondary: secondary ?? this.secondary,
      secondaryContainer: secondaryContainer ?? this.secondaryContainer,
      tertiary: tertiary ?? this.tertiary,
      tertiaryContainer: tertiaryContainer ?? this.tertiaryContainer,
      secondaryVariant: secondaryVariant ?? this.secondaryVariant,
      error: error ?? this.error,
      surface: surface ?? this.surface,
      background: background ?? this.background,
      scaffoldBackground: scaffoldBackground ?? this.scaffoldBackground,
      appBarBackground: appBarBackground ?? this.appBarBackground,
      dialogBackground: dialogBackground ?? this.dialogBackground,
      onPrimary: onPrimary ?? this.onPrimary,
      onPrimaryContainer: onPrimaryContainer ?? this.onPrimaryContainer,
      onSecondary: onSecondary ?? this.onSecondary,
      onSecondaryContainer: onSecondaryContainer ?? this.onSecondaryContainer,
      onTertiary: onTertiary ?? this.onTertiary,
      onTertiaryContainer: onTertiaryContainer ?? this.onTertiaryContainer,
      onSurface: onSurface ?? this.onSurface,
      onBackground: onBackground ?? this.onBackground,
      onError: onError ?? this.onError,
      surfaceTint: surfaceTint ?? this.surfaceTint,
      tabBarStyle: tabBarStyle ?? this.tabBarStyle,
      appBarElevation: appBarElevation ?? this.appBarElevation,
      bottomAppBarElevation:
          bottomAppBarElevation ?? this.bottomAppBarElevation,
      tooltipsMatchBackground:
          tooltipsMatchBackground ?? this.tooltipsMatchBackground,
      transparentStatusBar: transparentStatusBar ?? this.transparentStatusBar,
      visualDensity: visualDensity ?? this.visualDensity,
      textTheme: textTheme ?? this.textTheme,
      primaryTextTheme: primaryTextTheme ?? this.primaryTextTheme,
      fontFamily: fontFamily ?? this.fontFamily,
      platform: platform ?? this.platform,
      typography: typography ?? this.typography,
      applyElevationOverlayColor:
          applyElevationOverlayColor ?? this.applyElevationOverlayColor,
      subThemesData: subThemesData ?? this.subThemesData,
      useMaterial3: useMaterial3 ?? this.useMaterial3,
      extensions: extensions ?? this.extensions,
    );
  }

  /// Override the equality operator.
  @override
  bool operator ==(Object other) {
    if (identical(this, other)) return true;
    if (other.runtimeType != runtimeType) return false;
    return other is FlexColorScheme &&
        other.colorScheme == colorScheme &&
        other.brightness == brightness &&
        other.primary == primary &&
        other.primaryContainer == primaryContainer &&
        other.primaryVariant == primaryVariant &&
        other.secondary == secondary &&
        other.secondaryContainer == secondaryContainer &&
        other.secondaryVariant == secondaryVariant &&
        other.tertiary == tertiary &&
        other.tertiaryContainer == tertiaryContainer &&
        other.error == error &&
        other.surface == surface &&
        other.background == background &&
        other.scaffoldBackground == scaffoldBackground &&
        other.dialogBackground == dialogBackground &&
        other.appBarBackground == appBarBackground &&
        other.onPrimary == onPrimary &&
        other.onPrimaryContainer == onPrimaryContainer &&
        other.onSecondary == onSecondary &&
        other.onSecondaryContainer == onSecondaryContainer &&
        other.onTertiary == onTertiary &&
        other.onTertiaryContainer == onTertiaryContainer &&
        other.onSurface == onSurface &&
        other.onBackground == onBackground &&
        other.onError == onError &&
        other.surfaceTint == surfaceTint &&
        other.tabBarStyle == tabBarStyle &&
        other.appBarElevation == appBarElevation &&
        other.bottomAppBarElevation == bottomAppBarElevation &&
        other.tooltipsMatchBackground == tooltipsMatchBackground &&
        other.transparentStatusBar == transparentStatusBar &&
        other.visualDensity == visualDensity &&
        other.textTheme == textTheme &&
        other.primaryTextTheme == primaryTextTheme &&
        other.fontFamily == fontFamily &&
        other.platform == platform &&
        other.typography == typography &&
        other.applyElevationOverlayColor == applyElevationOverlayColor &&
        other.subThemesData == subThemesData &&
        other.useMaterial3 == useMaterial3 &&
        other.extensions == extensions;
  }

  /// Override for hashcode, dart.ui Jenkins based.
  @override
  int get hashCode => hashList(<Object?>[
        colorScheme,
        brightness,
        primary,
        primaryContainer,
        primaryVariant,
        secondary,
        secondaryContainer,
        secondaryVariant,
        tertiary,
        tertiaryContainer,
        error,
        surface,
        background,
        scaffoldBackground,
        dialogBackground,
        appBarBackground,
        onPrimary,
        onPrimaryContainer,
        onSecondary,
        onSecondaryContainer,
        onTertiary,
        onTertiaryContainer,
        onSurface,
        onBackground,
        onError,
        surfaceTint,
        tabBarStyle,
        appBarElevation,
        bottomAppBarElevation,
        tooltipsMatchBackground,
        transparentStatusBar,
        visualDensity,
        textTheme,
        primaryTextTheme,
        fontFamily,
        platform,
        typography,
        applyElevationOverlayColor,
        subThemesData,
        useMaterial3,
        extensions,
      ]);

  /// Flutter debug properties override, includes toString.
  @override
  void debugFillProperties(DiagnosticPropertiesBuilder properties) {
    super.debugFillProperties(properties);
    properties
        .add(DiagnosticsProperty<ColorScheme>('colorScheme', colorScheme));
    properties.add(EnumProperty<Brightness>('brightness', brightness));
    properties.add(ColorProperty('primary', primary));
    properties.add(ColorProperty('primaryContainer', primaryContainer));
    properties.add(ColorProperty('primaryVariant', primaryVariant));
    properties.add(ColorProperty('secondary', secondary));
    properties.add(ColorProperty('secondaryContainer', secondaryContainer));
    properties.add(ColorProperty('secondaryVariant', secondaryVariant));
    properties.add(ColorProperty('tertiary', tertiary));
    properties.add(ColorProperty('tertiaryContainer', tertiaryContainer));
    properties.add(ColorProperty('error', error));
    properties.add(ColorProperty('surface', surface));
    properties.add(ColorProperty('background', background));
    properties.add(ColorProperty('scaffoldBackground', scaffoldBackground));
    properties.add(ColorProperty('appBarBackground', appBarBackground));
    properties.add(ColorProperty('dialogBackground', dialogBackground));
    properties.add(ColorProperty('onPrimary', onPrimary));
    properties.add(ColorProperty('onPrimaryContainer', onPrimaryContainer));
    properties.add(ColorProperty('onSecondary', onSecondary));
    properties.add(ColorProperty('onSecondaryContainer', onSecondaryContainer));
    properties.add(ColorProperty('onTertiary', onTertiary));
    properties.add(ColorProperty('onTertiaryContainer', onTertiaryContainer));
    properties.add(ColorProperty('onSurface', onSurface));
    properties.add(ColorProperty('onBackground', onBackground));
    properties.add(ColorProperty('onError', onError));
    properties.add(ColorProperty('surfaceTint', surfaceTint));
    properties.add(EnumProperty<FlexTabBarStyle>('tabBarStyle', tabBarStyle));
    properties
        .add(DiagnosticsProperty<double>('appBarElevation', appBarElevation));
    properties.add(DiagnosticsProperty<double>(
        'bottomAppBarElevation', bottomAppBarElevation));
    properties.add(DiagnosticsProperty<bool>(
        'tooltipsMatchBackground', tooltipsMatchBackground));
    properties.add(DiagnosticsProperty<bool>(
        'transparentStatusBar', transparentStatusBar));
    properties.add(EnumProperty<VisualDensity>('visualDensity', visualDensity));
    properties.add(DiagnosticsProperty<TextTheme>('textTheme', textTheme));
    properties.add(
        DiagnosticsProperty<TextTheme>('primaryTextTheme', primaryTextTheme));
    properties.add(DiagnosticsProperty<String>('fontFamily', fontFamily));
    properties.add(EnumProperty<TargetPlatform>('platform', platform));
    properties.add(DiagnosticsProperty<Typography>('typography', typography));
    properties.add(DiagnosticsProperty<bool>(
        'applyElevationOverlayColor', applyElevationOverlayColor));
    properties.add(
        DiagnosticsProperty<FlexSubThemesData>('subThemesData', subThemesData));
    properties.add(DiagnosticsProperty<bool>('useMaterial3', useMaterial3));
    properties.add(
        IterableProperty<ThemeExtension<dynamic>>('extensions', extensions));
  }
}

/// Immutable data class used to make the six different surface colors in a
/// [FlexColorScheme].
///
/// [FlexSchemeSurfaceColors] is used primarily via the
/// [FlexSchemeSurfaceColors.blend] factory. Before version 4.0 the
/// [FlexSchemeSurfaceColors.from] factory was used.
///
/// Included colors are [surface], [surfaceVariant], [inverseSurface] and
/// [background], plus blended surface colors
/// for [scaffoldBackground] and [dialogBackground], which are not a part
/// of Flutter's standard [ColorScheme].
///
/// This class, and its factory are only used by the
/// [FlexColorScheme.light] and [FlexColorScheme.dark] factories. You normally
/// do not have to use it, unless you are making a customized version
/// of [FlexColorScheme] or similar feature, or if you want to, you can use it
/// for getting surface colors for a standard [ColorScheme].
@immutable
class FlexSchemeSurfaceColors with Diagnosticable {
  /// Default constructor. [FlexSchemeSurfaceColors] is usually created with
  /// the [FlexSchemeSurfaceColors.from] factory.
  const FlexSchemeSurfaceColors({
    required this.surface,
    Color? surfaceVariant,
    Color? inverseSurface,
    required this.dialogBackground,
    required this.background,
    required this.scaffoldBackground,
  })  : _surfaceVariant = surfaceVariant,
        _inverseSurface = inverseSurface;

  /// The background color for widgets like [Card] and [Dialog].
  ///
  /// The default background color of [Material] of type card.
  final Color surface;

  /// A color variant of [surface] that can be used for differentiation
  /// against a component using [surface]. Local variable with initializer used
  /// in order to not break past const interface, with past required props.
  final Color? _surfaceVariant;

  /// A color variant of [surface] that can be used for differentiation against
  /// a component using [surface]. Defaults to [surface] as fallback.
  Color get surfaceVariant => _surfaceVariant ?? surface;

  /// A surface color used for displaying the reverse of what’s seen in the
  /// surrounding UI, for example in a SnackBar to bring attention to
  /// an alert. Local variable with initializer used in order to not break
  /// past const interface, with past required props.
  final Color? _inverseSurface;

  /// A surface color used for displaying the reverse of what’s seen in the
  /// surrounding UI, for example in a SnackBar to bring attention to
  /// an alert.  Defaults to [surface] as fallback.
  Color get inverseSurface => _inverseSurface ?? surface;

  /// The color of dialog background.
  ///
  /// Typically same as the surface color.
  final Color dialogBackground;

  /// A color that typically appears behind scrollable content.
  ///
  /// The default background color of [Material] of type canvas.
  final Color background;

  /// The color of the [Scaffold] background.
  final Color scaffoldBackground;

  /// Create nuanced surface colors using pre-defined behavior via enum
  /// [FlexSurfaceMode] property `surfaceMode` or make totally custom color
  /// blended surfaces.
  ///
  /// [FlexSchemeSurfaceColors] were in versions before 4.0 created with
  /// the [FlexSchemeSurfaceColors.from] factory. Version 4.0 and later
  /// recommends using the [FlexSchemeSurfaceColors.blend] factory for even
  /// more nuanced surface color branding options and control.
  ///
  /// This kind of surface branding is based on the Material guide found
  /// under "Accessibility and contrast"
  /// https://material.io/design/color/dark-theme.html#properties
  /// for branded surfaces.
  ///
  /// The [brightness] controls if we are creating surface colors for light or
  /// dark surfaces.
  ///
  /// To get elevation overlay color in dark themes on all surfaces used by
  /// [Material], use a [FlexSurfaceMode] `surfaceMode` that start with
  /// `equal` in its name.
  /// Other modes will only use elevation overlay if their background happens to
  /// be equal to resulting colorScheme.surface color. For more information
  /// see issue: https://github.com/flutter/flutter/issues/90353
  ///
  /// The surface colors returned by this factory can also be used to make
  /// branded surface colors for Flutter's standard [ColorScheme], it does
  /// not have to be used exclusively by [FlexColorScheme].
  factory FlexSchemeSurfaceColors.blend({
    /// Controls if we create surface colors for light or dark surfaces.
    final Brightness brightness = Brightness.light,

    /// The used surface mode to create different surface color blends.
    ///
    /// Defaults to highBackground.
    final FlexSurfaceMode surfaceMode =
        FlexSurfaceMode.highBackgroundLowScaffold,

    /// The the blend level strength used for the mode.
    final int blendLevel = 0,

    /// An int divisor for surfaceVariant used to reduce it blend strength.
    ///
    /// Used when seedSchemes are used to lessen the blend on surfaceVariant
    /// so it does not get too much, since it already has a strong start blend.
    /// FlexColorScheme passes in 2, to half the blend value when seeded schemes
    /// are used.
    final int surfaceVariantBlendDivide = 1,

    /// The colors used to blend into surfaces when using `surfaceMode` mode
    /// based styles and modes.
    ///
    /// If null, default material light or dark scheme colors will be used as
    /// fallback, depending on if we are making light or dark surfaces.
    ///
    /// If a blend color for a surface is provided in `blendColors`, that color
    /// color always overrides used color from `schemeColor` selected based on
    /// `surfaceMode`.
    FlexSchemeColor? schemeColors,

    /// Custom colors to be blended into each surface color.
    ///
    /// If provided, these colors will be blended into each equivalent surface
    /// color.
    ///
    /// If it is null, then `schemeColors.primary` will be assigned to all
    /// surfaces. The used `surfaceMode` does in some modes override this and
    /// also uses other color from `schemeColors` to be blended into some
    /// surfaces.
    FlexSchemeSurfaceColors? blendColors,

    /// The surface colors that we will mix the blend colors into.
    ///
    /// If null, then Material default surface colors will be used for all
    /// surfaces, that we then mix in the `blendColors` into, unless the
    /// `surfaceMode` defines surface starting colors otherwise.
    ///
    /// In some modes the `surfaceMode` defines and overwrites `surfaceColors`
    /// with its own mode based starting surface colors for each surface.
    /// To ensure that the passed in `surfaceColors` are kept when using
    /// custom surface colors, use the mode [FlexSurfaceMode.custom]
    /// to construct surface colors with custom base surface colors.
    FlexSchemeSurfaceColors? surfaceColors,
  }) {
    assert(
        blendLevel >= 0 && blendLevel <= 40,
        'Only blend levels from 0 to 40 '
        'are allowed. Very high alpha blend levels may not produce results '
        'that are visually very appealing or useful.');
    int usedBlendLevel = blendLevel;
    // If above happens in none debug mode, use 0, no blends.
    if (blendLevel < 0 || blendLevel > 40) usedBlendLevel = 0;

    final bool isLight = brightness == Brightness.light;

    // We get scheme default blend in colors via brightness and Material
    // default colors for the theme mode, if it was not provided. It is
    // typically provided when making branded surfaces, but Material default
    // colors are used as fallback colors.
    final FlexSchemeColor scheme = schemeColors ??
        (isLight ? FlexColor.material.light : FlexColor.material.dark);
    // The color that should be blended into each surface, defaults to primary
    // color for all surfaces.
    FlexSchemeSurfaceColors blendColor = blendColors ??
        FlexSchemeSurfaceColors(
          surface: scheme.primary,
          surfaceVariant: scheme.primary,
          inverseSurface: scheme.primary,
          dialogBackground: scheme.primary,
          background: scheme.primary,
          scaffoldBackground: scheme.primary,
        );
    // Set dialog blend colors to secondary variant color for modes using it.
    if (surfaceMode == FlexSurfaceMode.levelSurfacesLowScaffoldVariantDialog ||
        surfaceMode == FlexSurfaceMode.highScaffoldLowSurfacesVariantDialog) {
      blendColor = blendColor.copyWith(dialogBackground: scheme.tertiary);
    }
    // We get surface starting default colors via brightness and Material
    // default colors if it was not provided. It is normally provided when
    // making branded surfaces, but Material default colors are used as
    // fallback colors.
    FlexSchemeSurfaceColors surface = surfaceColors ??
        (isLight
            ? const FlexSchemeSurfaceColors(
                surface: FlexColor.materialLightSurface,
                surfaceVariant: FlexColor.materialLightSurface,
                inverseSurface: FlexColor.materialDarkSurface,
                background: FlexColor.materialLightBackground,
                scaffoldBackground: FlexColor.materialLightScaffoldBackground,
                dialogBackground: FlexColor.materialLightSurface,
              )
            : const FlexSchemeSurfaceColors(
                surface: FlexColor.materialDarkSurface,
                surfaceVariant: FlexColor.materialDarkSurface,
                inverseSurface: FlexColor.materialLightSurface,
                background: FlexColor.materialDarkBackground,
                scaffoldBackground: FlexColor.materialDarkScaffoldBackground,
                dialogBackground: FlexColor.materialDarkSurface,
              ));
    // Below, when blendLevel is zero, we use Material default surfaces. We do
    // that for all cases so that blend level 0 matches Material 2 default
    // on level 0 for all surfaces modes, for higher than 0 the modes use
    // different starting points for their surfaces that may be darker than
    // Material 2 in dark mode, and a bit off white in white mode.
    // Doing so improves the color blends.
    //
    // If using `highBackgroundLowScaffold` or `highSurfaceLowScaffold` or
    // `highScaffoldLevelSurface` and `_blendLevel` we use the same mix of
    // starting surfaces as used in versions before 4.0 when using
    // `surfaceStyle` based surfaces and no blends via `FlexSurface.material`.
    if (surfaceMode == FlexSurfaceMode.highBackgroundLowScaffold ||
        surfaceMode == FlexSurfaceMode.highSurfaceLowScaffold ||
        surfaceMode == FlexSurfaceMode.highScaffoldLevelSurface) {
      if (usedBlendLevel == 0) {
        if (isLight) {
          surface = surfaceColors ??
              const FlexSchemeSurfaceColors(
                surface: FlexColor.materialLightSurface,
                surfaceVariant: FlexColor.materialLightSurface,
                inverseSurface: FlexColor.materialDarkSurface,
                background: FlexColor.materialLightBackground,
                scaffoldBackground: FlexColor.materialLightScaffoldBackground,
                dialogBackground: FlexColor.materialLightSurface,
              );
        } else {
          surface = surfaceColors ??
              const FlexSchemeSurfaceColors(
                surface: FlexColor.materialDarkSurface,
                surfaceVariant: FlexColor.materialDarkSurface,
                inverseSurface: FlexColor.materialLightSurface,
                background: FlexColor.materialDarkBackground,
                scaffoldBackground: FlexColor.materialDarkScaffoldBackground,
                dialogBackground: FlexColor.materialDarkSurface,
              );
        }
      } else {
        // For `blendLevel` > 0 we use the surface color defined by [FlexColor]
        // surfaces. They differ slightly
        // from Material starting colors to provide better blend effects.
        // White is slightly off-white for background and in dark mode
        // surface is slightly darker and background even darker, while
        // scaffold background matches the Material design background.
        if (isLight) {
          surface = surfaceColors ??
              const FlexSchemeSurfaceColors(
                surface: FlexColor.lightSurface,
                surfaceVariant: FlexColor.lightSurface,
                inverseSurface: FlexColor.darkSurface,
                background: FlexColor.lightBackground,
                scaffoldBackground: FlexColor.lightScaffoldBackground,
                dialogBackground: FlexColor.lightSurface,
              );
        } else {
          surface = surfaceColors ??
              const FlexSchemeSurfaceColors(
                surface: FlexColor.darkSurface,
                surfaceVariant: FlexColor.darkSurface,
                inverseSurface: FlexColor.lightSurface,
                background: FlexColor.darkBackground,
                scaffoldBackground: FlexColor.darkScaffoldBackground,
                dialogBackground: FlexColor.darkSurface,
              );
        }
      }
    }
    // In these modes we use FlexColor default surface color on all surfaces,
    // when blend level is > 0.
    if (surfaceMode == FlexSurfaceMode.level ||
        surfaceMode == FlexSurfaceMode.highScaffoldLowSurface ||
        surfaceMode == FlexSurfaceMode.levelSurfacesLowScaffold ||
        surfaceMode == FlexSurfaceMode.levelSurfacesLowScaffoldVariantDialog) {
      if (usedBlendLevel == 0) {
        if (isLight) {
          surface = surfaceColors ??
              const FlexSchemeSurfaceColors(
                surface: FlexColor.materialLightSurface,
                surfaceVariant: FlexColor.materialLightSurface,
                inverseSurface: FlexColor.materialDarkSurface,
                background: FlexColor.materialLightBackground,
                scaffoldBackground: FlexColor.materialLightScaffoldBackground,
                dialogBackground: FlexColor.materialLightSurface,
              );
        } else {
          surface = surfaceColors ??
              const FlexSchemeSurfaceColors(
                surface: FlexColor.materialDarkSurface,
                surfaceVariant: FlexColor.materialDarkSurface,
                inverseSurface: FlexColor.materialLightSurface,
                background: FlexColor.materialDarkBackground,
                scaffoldBackground: FlexColor.materialDarkScaffoldBackground,
                dialogBackground: FlexColor.materialDarkSurface,
              );
        }
      } else {
        if (isLight) {
          surface = surfaceColors ??
              const FlexSchemeSurfaceColors(
                surface: FlexColor.lightSurface,
                surfaceVariant: FlexColor.lightSurface,
                inverseSurface: FlexColor.darkSurface,
                background: FlexColor.lightSurface,
                scaffoldBackground: FlexColor.lightSurface,
                dialogBackground: FlexColor.lightSurface,
              );
        } else {
          surface = surfaceColors ??
              const FlexSchemeSurfaceColors(
                surface: FlexColor.darkSurface,
                surfaceVariant: FlexColor.darkSurface,
                inverseSurface: FlexColor.lightSurface,
                background: FlexColor.darkSurface,
                scaffoldBackground: FlexColor.darkSurface,
                dialogBackground: FlexColor.darkSurface,
              );
        }
      }
    }
    // In mode `highScaffoldLowSurfaces` and
    // `highScaffoldLowSurfacesVariantDialog`, we use FlexColor
    // default background color on all surfaces. The FlexColor background color
    // is slightly darker in dark mode and a bit off white in light mode,
    // as compared to FlexColor.lightSurface and dark surface.
    if (surfaceMode == FlexSurfaceMode.highScaffoldLowSurfaces ||
        surfaceMode == FlexSurfaceMode.highScaffoldLowSurfacesVariantDialog) {
      if (usedBlendLevel == 0) {
        if (isLight) {
          surface = surfaceColors ??
              const FlexSchemeSurfaceColors(
                surface: FlexColor.materialLightSurface,
                surfaceVariant: FlexColor.materialLightSurface,
                inverseSurface: FlexColor.materialDarkSurface,
                background: FlexColor.materialLightBackground,
                scaffoldBackground: FlexColor.materialLightScaffoldBackground,
                dialogBackground: FlexColor.materialLightSurface,
              );
        } else {
          surface = surfaceColors ??
              const FlexSchemeSurfaceColors(
                surface: FlexColor.materialDarkSurface,
                surfaceVariant: FlexColor.materialDarkSurface,
                inverseSurface: FlexColor.materialLightSurface,
                background: FlexColor.materialDarkBackground,
                scaffoldBackground: FlexColor.materialDarkScaffoldBackground,
                dialogBackground: FlexColor.materialDarkSurface,
              );
        }
      } else {
        if (isLight) {
          surface = surfaceColors ??
              const FlexSchemeSurfaceColors(
                surface: FlexColor.lightBackground,
                surfaceVariant: FlexColor.lightBackground,
                inverseSurface: FlexColor.darkBackground,
                background: FlexColor.lightBackground,
                scaffoldBackground: FlexColor.lightBackground,
                dialogBackground: FlexColor.lightBackground,
              );
        } else {
          surface = surfaceColors ??
              const FlexSchemeSurfaceColors(
                surface: FlexColor.darkBackground,
                surfaceVariant: FlexColor.darkBackground,
                inverseSurface: FlexColor.lightBackground,
                background: FlexColor.darkBackground,
                scaffoldBackground: FlexColor.darkBackground,
                dialogBackground: FlexColor.darkBackground,
              );
        }
      }
    }
    // Get alpha blend values corresponding to used mode, level and brightness.
    final _AlphaValues alphaValue =
        _AlphaValues.getAlphas(surfaceMode, usedBlendLevel);
    // Return the computed and resulting surface colors.
    return FlexSchemeSurfaceColors(
      surface: surface.surface
          .blendAlpha(blendColor.surface, alphaValue.surfaceAlpha),
      surfaceVariant: surface.surfaceVariant.blendAlpha(
          blendColor.surfaceVariant,
          alphaValue.surfaceVariantAlpha ~/ surfaceVariantBlendDivide),
      inverseSurface: surface.inverseSurface.blendAlpha(
          blendColor.inverseSurface, alphaValue.inverseSurfaceAlpha),
      dialogBackground: surface.dialogBackground
          .blendAlpha(blendColor.dialogBackground, alphaValue.dialogAlpha),
      background: surface.background
          .blendAlpha(blendColor.background, alphaValue.backgroundAlpha),
      scaffoldBackground: surface.scaffoldBackground
          .blendAlpha(blendColor.scaffoldBackground, alphaValue.scaffoldAlpha),
    );
  }

  /// Copy the object with one or more provided properties changed.
  FlexSchemeSurfaceColors copyWith({
    Color? surface,
    Color? surfaceVariant,
    Color? inverseSurface,
    Color? background,
    Color? scaffoldBackground,
    Color? dialogBackground,
  }) {
    return FlexSchemeSurfaceColors(
      surface: surface ?? this.surface,
      surfaceVariant: surfaceVariant ?? this.surfaceVariant,
      inverseSurface: inverseSurface ?? this.inverseSurface,
      background: background ?? this.background,
      scaffoldBackground: scaffoldBackground ?? this.scaffoldBackground,
      dialogBackground: dialogBackground ?? this.dialogBackground,
    );
  }

  /// Override the equality operator.
  @override
  bool operator ==(Object other) {
    if (identical(this, other)) return true;
    if (other.runtimeType != runtimeType) return false;
    return other is FlexSchemeSurfaceColors &&
        other.surface == surface &&
        other.surfaceVariant == surfaceVariant &&
        other.inverseSurface == inverseSurface &&
        other.background == background &&
        other.scaffoldBackground == scaffoldBackground &&
        other.dialogBackground == dialogBackground;
  }

  /// Override for hashcode, dart.ui Jenkins based.
  @override
  int get hashCode => hashValues(
        surface,
        surfaceVariant,
        inverseSurface,
        background,
        scaffoldBackground,
        dialogBackground,
      );

  /// Flutter debug properties override, includes toString.
  @override
  void debugFillProperties(DiagnosticPropertiesBuilder properties) {
    super.debugFillProperties(properties);
    properties.add(ColorProperty('surface', surface));
    properties.add(ColorProperty('surfaceVariant', surfaceVariant));
    properties.add(ColorProperty('inverseSurface', inverseSurface));
    properties.add(ColorProperty('background', background));
    properties.add(ColorProperty('scaffoldBackground', scaffoldBackground));
    properties.add(ColorProperty('dialogBackground', dialogBackground));
  }
}

// Private class to hold alpha values for a given FlexSurfaceMode blend mode
// and blend level and static helper to compute the alpha blend values.
@immutable
class _AlphaValues {
  const _AlphaValues({
    this.primaryAlpha = 0,
    this.primaryContainerAlpha = 0,
    this.secondaryAlpha = 0,
    this.secondaryContainerAlpha = 0,
    this.tertiaryAlpha = 0,
    this.tertiaryContainerAlpha = 0,
    this.errorAlpha = 0,
    this.errorContainerAlpha = 0,
    this.surfaceAlpha = 0,
    this.surfaceVariantAlpha = 0,
    this.inverseSurfaceAlpha = 0,
    this.dialogAlpha = 0,
    this.backgroundAlpha = 0,
    this.scaffoldAlpha = 0,
  });

  /// Alpha blend value for primary color.
  final int primaryAlpha;

  /// Alpha blend value for primaryContainer color.
  final int primaryContainerAlpha;

  /// Alpha blend value for secondary color.
  final int secondaryAlpha;

  /// Alpha blend value for secondaryContainer color.
  final int secondaryContainerAlpha;

  /// Alpha blend value for tertiary color.
  final int tertiaryAlpha;

  /// Alpha blend value for tertiaryContainer color.
  final int tertiaryContainerAlpha;

  /// Alpha blend value for error color.
  final int errorAlpha;

  /// Alpha blend value for error container color.
  final int errorContainerAlpha;

  /// Alpha blend value for surface color.
  final int surfaceAlpha;

  /// Alpha blend value for surfaceVariant color.
  final int surfaceVariantAlpha;

  /// Alpha blend value for inverseSurface color.
  final int inverseSurfaceAlpha;

  /// Alpha blend value for dialog color.
  final int dialogAlpha;

  /// Alpha blend value for background color.
  final int backgroundAlpha;

  /// Alpha blend value for scaffold background color.
  final int scaffoldAlpha;

  // Returns alpha values for a given blend level and blend mode and brightness.
  static _AlphaValues getAlphas(
      final FlexSurfaceMode mode, final int blendLevel) {
    switch (mode) {
      case FlexSurfaceMode.level:
      case FlexSurfaceMode.custom:
        // Result: Background (1x) Surface (1x) Scaffold (1x),
        // surfaceVariant (Surface*2)
        return _AlphaValues(
          primaryAlpha: blendLevel,
          primaryContainerAlpha: blendLevel * 2,
          secondaryAlpha: blendLevel,
          secondaryContainerAlpha: blendLevel * 2,
          tertiaryAlpha: blendLevel,
          tertiaryContainerAlpha: blendLevel * 2,
          errorAlpha: blendLevel,
          errorContainerAlpha: blendLevel * 2,
          surfaceAlpha: blendLevel,
          surfaceVariantAlpha: blendLevel * 2,
          inverseSurfaceAlpha: blendLevel,
          dialogAlpha: blendLevel,
          backgroundAlpha: blendLevel,
          scaffoldAlpha: blendLevel,
        );
      // Result: Background (3/2x) Surface & (1x) Scaffold (1/2x).
      // surfaceVariant (Surface*2)
      case FlexSurfaceMode.highBackgroundLowScaffold:
        return _AlphaValues(
          primaryAlpha: blendLevel,
          primaryContainerAlpha: blendLevel * 2,
          secondaryAlpha: blendLevel,
          secondaryContainerAlpha: blendLevel * 2,
          tertiaryAlpha: blendLevel,
          tertiaryContainerAlpha: blendLevel * 2,
          errorAlpha: blendLevel,
          errorContainerAlpha: blendLevel * 2,
          surfaceAlpha: blendLevel,
          surfaceVariantAlpha: blendLevel * 2,
          inverseSurfaceAlpha: blendLevel,
          dialogAlpha: blendLevel,
          backgroundAlpha: blendLevel * 3 ~/ 2,
          scaffoldAlpha: blendLevel ~/ 2,
        );
      // Result: Surface (3/2x) Background (1x) Scaffold (1/2x).
      // surfaceVariant (Surface*3/2)
      case FlexSurfaceMode.highSurfaceLowScaffold:
        return _AlphaValues(
          primaryAlpha: blendLevel,
          primaryContainerAlpha: blendLevel * 2,
          secondaryAlpha: blendLevel,
          secondaryContainerAlpha: blendLevel * 2,
          tertiaryAlpha: blendLevel,
          tertiaryContainerAlpha: blendLevel * 2,
          errorAlpha: blendLevel,
          errorContainerAlpha: blendLevel * 2,
          surfaceAlpha: blendLevel * 3 ~/ 2,
          surfaceVariantAlpha: blendLevel * 3 ~/ 2 * 3 ~/ 2,
          inverseSurfaceAlpha: blendLevel * 3 ~/ 2,
          dialogAlpha: blendLevel * 3 ~/ 2,
          backgroundAlpha: blendLevel,
          scaffoldAlpha: blendLevel ~/ 2,
        );
      // Result: Scaffold (3x) Background (1x) Surface (1/2x).
      // surfaceVariant (Surface*2)
      case FlexSurfaceMode.highScaffoldLowSurface:
        return _AlphaValues(
          primaryAlpha: blendLevel,
          primaryContainerAlpha: blendLevel * 2,
          secondaryAlpha: blendLevel,
          secondaryContainerAlpha: blendLevel * 2,
          tertiaryAlpha: blendLevel,
          tertiaryContainerAlpha: blendLevel * 2,
          errorAlpha: blendLevel,
          errorContainerAlpha: blendLevel * 2,
          surfaceAlpha: blendLevel ~/ 2,
          surfaceVariantAlpha: blendLevel ~/ 2 * 2,
          inverseSurfaceAlpha: blendLevel ~/ 2,
          dialogAlpha: blendLevel ~/ 2,
          backgroundAlpha: blendLevel,
          scaffoldAlpha: blendLevel * 3,
        );
      // Result: Scaffold (3x) background (3/2x) surface (1x).
      // surfaceVariant (Surface*2)
      case FlexSurfaceMode.highScaffoldLevelSurface:
        return _AlphaValues(
          primaryAlpha: blendLevel,
          primaryContainerAlpha: blendLevel * 2,
          secondaryAlpha: blendLevel,
          secondaryContainerAlpha: blendLevel * 2,
          tertiaryAlpha: blendLevel,
          tertiaryContainerAlpha: blendLevel * 2,
          errorAlpha: blendLevel,
          errorContainerAlpha: blendLevel * 2,
          surfaceAlpha: blendLevel,
          surfaceVariantAlpha: blendLevel * 2,
          inverseSurfaceAlpha: blendLevel,
          dialogAlpha: blendLevel,
          backgroundAlpha: blendLevel * 3 ~/ 2,
          scaffoldAlpha: blendLevel * 3,
        );
      // Result: (1x) Surface and Background (1x) Scaffold (1/2x).
      // surfaceVariant (Surface*2)
      case FlexSurfaceMode.levelSurfacesLowScaffold:
      case FlexSurfaceMode.levelSurfacesLowScaffoldVariantDialog:
        return _AlphaValues(
          primaryAlpha: blendLevel,
          primaryContainerAlpha: blendLevel * 2,
          secondaryAlpha: blendLevel,
          secondaryContainerAlpha: blendLevel * 2,
          tertiaryAlpha: blendLevel,
          tertiaryContainerAlpha: blendLevel * 2,
          errorAlpha: blendLevel,
          errorContainerAlpha: blendLevel * 2,
          surfaceAlpha: blendLevel,
          surfaceVariantAlpha: blendLevel * 2,
          inverseSurfaceAlpha: blendLevel,
          dialogAlpha: blendLevel,
          backgroundAlpha: blendLevel,
          scaffoldAlpha: blendLevel ~/ 2,
        );
      // Result: Scaffold (3x) Surface and background (1/2x).
      // surfaceVariant (Surface*2)
      case FlexSurfaceMode.highScaffoldLowSurfaces:
      case FlexSurfaceMode.highScaffoldLowSurfacesVariantDialog:
        return _AlphaValues(
          primaryAlpha: blendLevel,
          primaryContainerAlpha: blendLevel * 2,
          secondaryAlpha: blendLevel,
          secondaryContainerAlpha: blendLevel * 2,
          tertiaryAlpha: blendLevel,
          tertiaryContainerAlpha: blendLevel * 2,
          errorAlpha: blendLevel,
          errorContainerAlpha: blendLevel * 2,
          surfaceAlpha: blendLevel ~/ 2,
          surfaceVariantAlpha: blendLevel ~/ 2 * 2,
          inverseSurfaceAlpha: blendLevel ~/ 2,
          dialogAlpha: blendLevel ~/ 2,
          backgroundAlpha: blendLevel ~/ 2,
          scaffoldAlpha: blendLevel * 3,
        );
    }
  }
}

/// This class is the same concept as Flutter's [ColorScheme] class.
///
/// It is used used to generate a scheme based on a modified version of
/// [CorePalette] found in package material_color_utilities. It is a simple
/// modification of [Scheme] found in same "material_color_utilities" package.
///
/// It uses two changes that makes it more flexible:
///
/// 1) Three seed colors instead of just one.
///
/// Instead of [CorePalette] it uses inherited version called [FlexCorePalette]
/// that enables using 1, 2 or 3 seed colors for more degrees
/// of freedom in seeded ColorScheme, using defined seed colors for
/// primary, secondary and tertiary colors. The extended [FlexCorePalette]
/// version also allows for adjusting chroma usage and levels that are
/// hard coded into M3 design [CorePalette].
///
/// 2) Configurable tone to ColorScheme mapping.
///
/// Which tones to use for what color in the [ColorScheme] is not hard coded
/// like it is in material_color_utilities [Scheme] class. It also
/// accepts an optional [FlexTones] class that can be used to configure
/// all the tone mapping from [TonalPalette] to [ColorScheme], including
/// passing all the extra min chroma and fixed level parameters it should
/// use when it makes the [FlexCorePalette] that is maps color from to
/// the [ColorScheme].
///
/// Keeping this helper class private for now in [FlexColorScheme], if there
/// ever is a request for making it available directly via the library,
/// post an issue and we will consider it.
class _Scheme {
  final int primary;
  final int onPrimary;
  final int primaryContainer;
  final int onPrimaryContainer;
  final int secondary;
  final int onSecondary;
  final int secondaryContainer;
  final int onSecondaryContainer;
  final int tertiary;
  final int onTertiary;
  final int tertiaryContainer;
  final int onTertiaryContainer;
  final int error;
  final int onError;
  final int errorContainer;
  final int onErrorContainer;
  final int background;
  final int onBackground;
  final int surface;
  final int onSurface;
  final int surfaceVariant;
  final int onSurfaceVariant;
  final int outline;
  final int shadow;
  final int inverseSurface;
  final int inverseOnSurface;
  final int inversePrimary;

  const _Scheme({
    required this.primary,
    required this.onPrimary,
    required this.primaryContainer,
    required this.onPrimaryContainer,
    required this.secondary,
    required this.onSecondary,
    required this.secondaryContainer,
    required this.onSecondaryContainer,
    required this.tertiary,
    required this.onTertiary,
    required this.tertiaryContainer,
    required this.onTertiaryContainer,
    required this.error,
    required this.onError,
    required this.errorContainer,
    required this.onErrorContainer,
    required this.background,
    required this.onBackground,
    required this.surface,
    required this.onSurface,
    required this.surfaceVariant,
    required this.onSurfaceVariant,
    required this.outline,
    required this.shadow,
    required this.inverseSurface,
    required this.inverseOnSurface,
    required this.inversePrimary,
  });

  static _Scheme tones({
    required int primaryKey,
    int? secondaryKey,
    int? tertiaryKey,
    required FlexTones tones,
  }) {
    final FlexCorePalette core = FlexCorePalette.fromSeeds(
      primary: primaryKey,
      secondary: secondaryKey,
      tertiary: tertiaryKey,
      primaryChroma: tones.primaryChroma,
      primaryMinChroma: tones.primaryMinChroma,
      secondaryChroma: tones.secondaryChroma,
      secondaryMinChroma: tones.secondaryMinChroma,
      tertiaryChroma: tones.tertiaryChroma,
      tertiaryMinChroma: tones.tertiaryMinChroma,
      neutralChroma: tones.neutralChroma,
      neutralVariantChroma: tones.neutralVariantChroma,
    );
    return _Scheme(
      primary: core.primary.get(tones.primaryTone),
      onPrimary: core.primary.get(tones.onPrimaryTone),
      primaryContainer: core.primary.get(tones.primaryContainerTone),
      onPrimaryContainer: core.primary.get(tones.onPrimaryContainerTone),
      secondary: core.secondary.get(tones.secondaryTone),
      onSecondary: core.secondary.get(tones.onSecondaryTone),
      secondaryContainer: core.secondary.get(tones.secondaryContainerTone),
      onSecondaryContainer: core.secondary.get(tones.onSecondaryContainerTone),
      tertiary: core.tertiary.get(tones.tertiaryTone),
      onTertiary: core.tertiary.get(tones.onTertiaryTone),
      tertiaryContainer: core.tertiary.get(tones.tertiaryContainerTone),
      onTertiaryContainer: core.tertiary.get(tones.onTertiaryContainerTone),
      error: core.error.get(tones.errorTone),
      onError: core.error.get(tones.onErrorTone),
      errorContainer: core.error.get(tones.errorContainerTone),
      onErrorContainer: core.error.get(tones.onErrorContainerTone),
      background: core.neutral.get(tones.backgroundTone),
      onBackground: core.neutral.get(tones.onBackgroundTone),
      surface: core.neutral.get(tones.surfaceTone),
      onSurface: core.neutral.get(tones.onSurfaceTone),
      surfaceVariant: core.neutralVariant.get(tones.surfaceVariantTone),
      onSurfaceVariant: core.neutralVariant.get(tones.onSurfaceVariantTone),
      outline: core.neutralVariant.get(tones.outlineTone),
      shadow: core.neutral.get(tones.shadowTone),
      inverseSurface: core.neutral.get(tones.inverseSurfaceTone),
      inverseOnSurface: core.neutral.get(tones.onInverseSurfaceTone),
      inversePrimary: core.primary.get(tones.inversePrimaryTone),
    );
  }

  static ColorScheme fromSeeds({
    required Color primaryKey,
    Color? secondaryKey,
    Color? tertiaryKey,
    FlexTones? tones,
    Brightness brightness = Brightness.light,
    Color? primary,
    Color? onPrimary,
    Color? primaryContainer,
    Color? onPrimaryContainer,
    Color? secondary,
    Color? onSecondary,
    Color? secondaryContainer,
    Color? onSecondaryContainer,
    Color? tertiary,
    Color? onTertiary,
    Color? tertiaryContainer,
    Color? onTertiaryContainer,
    Color? error,
    Color? onError,
    Color? errorContainer,
    Color? onErrorContainer,
    Color? outline,
    Color? background,
    Color? onBackground,
    Color? surface,
    Color? onSurface,
    Color? surfaceVariant,
    Color? onSurfaceVariant,
    Color? inverseSurface,
    Color? onInverseSurface,
    Color? inversePrimary,
    Color? shadow,
    Color? surfaceTint,
  }) {
    final _Scheme scheme;
    switch (brightness) {
      case Brightness.light:
        scheme = _Scheme.tones(
          primaryKey: primaryKey.value,
          secondaryKey: secondaryKey?.value,
          tertiaryKey: tertiaryKey?.value,
          tones: tones ?? const FlexTones.light(),
        );
        break;
      case Brightness.dark:
        scheme = _Scheme.tones(
          primaryKey: primaryKey.value,
          secondaryKey: secondaryKey?.value,
          tertiaryKey: tertiaryKey?.value,
          tones: tones ?? const FlexTones.dark(),
        );
        break;
    }
    return ColorScheme(
      primary: primary ?? Color(scheme.primary),
      onPrimary: onPrimary ?? Color(scheme.onPrimary),
      primaryContainer: primaryContainer ?? Color(scheme.primaryContainer),
      onPrimaryContainer:
          onPrimaryContainer ?? Color(scheme.onPrimaryContainer),
      secondary: secondary ?? Color(scheme.secondary),
      onSecondary: onSecondary ?? Color(scheme.onSecondary),
      secondaryContainer:
          secondaryContainer ?? Color(scheme.secondaryContainer),
      onSecondaryContainer:
          onSecondaryContainer ?? Color(scheme.onSecondaryContainer),
      tertiary: tertiary ?? Color(scheme.tertiary),
      onTertiary: onTertiary ?? Color(scheme.onTertiary),
      tertiaryContainer: tertiaryContainer ?? Color(scheme.tertiaryContainer),
      onTertiaryContainer:
          onTertiaryContainer ?? Color(scheme.onTertiaryContainer),
      error: error ?? Color(scheme.error),
      onError: onError ?? Color(scheme.onError),
      errorContainer: errorContainer ?? Color(scheme.errorContainer),
      onErrorContainer: onErrorContainer ?? Color(scheme.onErrorContainer),
      outline: outline ?? Color(scheme.outline),
      background: background ?? Color(scheme.background),
      onBackground: onBackground ?? Color(scheme.onBackground),
      surface: surface ?? Color(scheme.surface),
      onSurface: onSurface ?? Color(scheme.onSurface),
      surfaceVariant: surfaceVariant ?? Color(scheme.surfaceVariant),
      onSurfaceVariant: onSurfaceVariant ?? Color(scheme.onSurfaceVariant),
      inverseSurface: inverseSurface ?? Color(scheme.inverseSurface),
      onInverseSurface: onInverseSurface ?? Color(scheme.inverseOnSurface),
      inversePrimary: inversePrimary ?? Color(scheme.inversePrimary),
      shadow: shadow ?? Color(scheme.shadow),
      surfaceTint: surfaceTint ?? Color(scheme.primary),
      brightness: brightness,
    );
  }
}