color.js

import define, {extend} from "./define.js";

export function Color() {}

export var darker = 0.7;
export var brighter = 1 / darker;

var reI = "\\s*([+-]?\\d+)\\s*",
    reN = "\\s*([+-]?\\d*\\.?\\d+(?:[eE][+-]?\\d+)?)\\s*",
    reP = "\\s*([+-]?\\d*\\.?\\d+(?:[eE][+-]?\\d+)?)%\\s*",
    reHex3 = /^#([0-9a-f]{3})$/,
    reHex4 = /^#([0-9a-f]{4})$/,
    reHex6 = /^#([0-9a-f]{6})$/,
    reHex8 = /^#([0-9a-f]{8})$/,
    reRgbInteger = new RegExp("^rgb\\(" + [reI, reI, reI] + "\\)$"),
    reRgbPercent = new RegExp("^rgb\\(" + [reP, reP, reP] + "\\)$"),
    reRgbaInteger = new RegExp("^rgba\\(" + [reI, reI, reI, reN] + "\\)$"),
    reRgbaPercent = new RegExp("^rgba\\(" + [reP, reP, reP, reN] + "\\)$"),
    reHslPercent = new RegExp("^hsl\\(" + [reN, reP, reP] + "\\)$"),
    reHslaPercent = new RegExp("^hsla\\(" + [reN, reP, reP, reN] + "\\)$");

var named = {
  aliceblue: 0xf0f8ff,
  antiquewhite: 0xfaebd7,
  aqua: 0x00ffff,
  aquamarine: 0x7fffd4,
  azure: 0xf0ffff,
  beige: 0xf5f5dc,
  bisque: 0xffe4c4,
  black: 0x000000,
  blanchedalmond: 0xffebcd,
  blue: 0x0000ff,
  blueviolet: 0x8a2be2,
  brown: 0xa52a2a,
  burlywood: 0xdeb887,
  cadetblue: 0x5f9ea0,
  chartreuse: 0x7fff00,
  chocolate: 0xd2691e,
  coral: 0xff7f50,
  cornflowerblue: 0x6495ed,
  cornsilk: 0xfff8dc,
  crimson: 0xdc143c,
  cyan: 0x00ffff,
  darkblue: 0x00008b,
  darkcyan: 0x008b8b,
  darkgoldenrod: 0xb8860b,
  darkgray: 0xa9a9a9,
  darkgreen: 0x006400,
  darkgrey: 0xa9a9a9,
  darkkhaki: 0xbdb76b,
  darkmagenta: 0x8b008b,
  darkolivegreen: 0x556b2f,
  darkorange: 0xff8c00,
  darkorchid: 0x9932cc,
  darkred: 0x8b0000,
  darksalmon: 0xe9967a,
  darkseagreen: 0x8fbc8f,
  darkslateblue: 0x483d8b,
  darkslategray: 0x2f4f4f,
  darkslategrey: 0x2f4f4f,
  darkturquoise: 0x00ced1,
  darkviolet: 0x9400d3,
  deeppink: 0xff1493,
  deepskyblue: 0x00bfff,
  dimgray: 0x696969,
  dimgrey: 0x696969,
  dodgerblue: 0x1e90ff,
  firebrick: 0xb22222,
  floralwhite: 0xfffaf0,
  forestgreen: 0x228b22,
  fuchsia: 0xff00ff,
  gainsboro: 0xdcdcdc,
  ghostwhite: 0xf8f8ff,
  gold: 0xffd700,
  goldenrod: 0xdaa520,
  gray: 0x808080,
  green: 0x008000,
  greenyellow: 0xadff2f,
  grey: 0x808080,
  honeydew: 0xf0fff0,
  hotpink: 0xff69b4,
  indianred: 0xcd5c5c,
  indigo: 0x4b0082,
  ivory: 0xfffff0,
  khaki: 0xf0e68c,
  lavender: 0xe6e6fa,
  lavenderblush: 0xfff0f5,
  lawngreen: 0x7cfc00,
  lemonchiffon: 0xfffacd,
  lightblue: 0xadd8e6,
  lightcoral: 0xf08080,
  lightcyan: 0xe0ffff,
  lightgoldenrodyellow: 0xfafad2,
  lightgray: 0xd3d3d3,
  lightgreen: 0x90ee90,
  lightgrey: 0xd3d3d3,
  lightpink: 0xffb6c1,
  lightsalmon: 0xffa07a,
  lightseagreen: 0x20b2aa,
  lightskyblue: 0x87cefa,
  lightslategray: 0x778899,
  lightslategrey: 0x778899,
  lightsteelblue: 0xb0c4de,
  lightyellow: 0xffffe0,
  lime: 0x00ff00,
  limegreen: 0x32cd32,
  linen: 0xfaf0e6,
  magenta: 0xff00ff,
  maroon: 0x800000,
  mediumaquamarine: 0x66cdaa,
  mediumblue: 0x0000cd,
  mediumorchid: 0xba55d3,
  mediumpurple: 0x9370db,
  mediumseagreen: 0x3cb371,
  mediumslateblue: 0x7b68ee,
  mediumspringgreen: 0x00fa9a,
  mediumturquoise: 0x48d1cc,
  mediumvioletred: 0xc71585,
  midnightblue: 0x191970,
  mintcream: 0xf5fffa,
  mistyrose: 0xffe4e1,
  moccasin: 0xffe4b5,
  navajowhite: 0xffdead,
  navy: 0x000080,
  oldlace: 0xfdf5e6,
  olive: 0x808000,
  olivedrab: 0x6b8e23,
  orange: 0xffa500,
  orangered: 0xff4500,
  orchid: 0xda70d6,
  palegoldenrod: 0xeee8aa,
  palegreen: 0x98fb98,
  paleturquoise: 0xafeeee,
  palevioletred: 0xdb7093,
  papayawhip: 0xffefd5,
  peachpuff: 0xffdab9,
  peru: 0xcd853f,
  pink: 0xffc0cb,
  plum: 0xdda0dd,
  powderblue: 0xb0e0e6,
  purple: 0x800080,
  rebeccapurple: 0x663399,
  red: 0xff0000,
  rosybrown: 0xbc8f8f,
  royalblue: 0x4169e1,
  saddlebrown: 0x8b4513,
  salmon: 0xfa8072,
  sandybrown: 0xf4a460,
  seagreen: 0x2e8b57,
  seashell: 0xfff5ee,
  sienna: 0xa0522d,
  silver: 0xc0c0c0,
  skyblue: 0x87ceeb,
  slateblue: 0x6a5acd,
  slategray: 0x708090,
  slategrey: 0x708090,
  snow: 0xfffafa,
  springgreen: 0x00ff7f,
  steelblue: 0x4682b4,
  tan: 0xd2b48c,
  teal: 0x008080,
  thistle: 0xd8bfd8,
  tomato: 0xff6347,
  turquoise: 0x40e0d0,
  violet: 0xee82ee,
  wheat: 0xf5deb3,
  white: 0xffffff,
  whitesmoke: 0xf5f5f5,
  yellow: 0xffff00,
  yellowgreen: 0x9acd32
};

define(Color, color, {
  copy: function(channels) {
    return Object.assign(new this.constructor, this, channels);
  },
  displayable: function() {
    return this.rgb().displayable();
  },
  hex: color_formatHex, // Deprecated! Use color.formatHex.
  formatHex: color_formatHex,
  formatHsl: color_formatHsl,
  formatRgb: color_formatRgb,
  toString: color_formatRgb
});

function color_formatHex() {
  return this.rgb().formatHex();
}

function color_formatHsl() {
  return hslConvert(this).formatHsl();
}

function color_formatRgb() {
  return this.rgb().formatRgb();
}

export default function color(format) {
  var m;
  format = (format + "").trim().toLowerCase();
  return (m = reHex3.exec(format)) ? (m = parseInt(m[1], 16), new Rgb((m >> 8 & 0xf) | (m >> 4 & 0xf0), (m >> 4 & 0xf) | (m & 0xf0), ((m & 0xf) << 4) | (m & 0xf), 1)) // #f00
      : (m = reHex4.exec(format)) ? (m = parseInt(m[1], 16), new Rgb((m >> 12 & 0xf) | (m >> 8 & 0xf0), (m >> 8 & 0xf) | (m >> 4 & 0xf0), (m >> 4 & 0xf) | (m & 0xf0), (((m & 0xf) << 4) | (m & 0xf)) / 0xff)) // #f000
      : (m = reHex6.exec(format)) ? rgbn(parseInt(m[1], 16)) // #ff0000
      : (m = reHex8.exec(format)) ? rgbn8(parseInt(m[1], 16)) // #ff000000
      : (m = reRgbInteger.exec(format)) ? new Rgb(m[1], m[2], m[3], 1) // rgb(255, 0, 0)
      : (m = reRgbPercent.exec(format)) ? new Rgb(m[1] * 255 / 100, m[2] * 255 / 100, m[3] * 255 / 100, 1) // rgb(100%, 0%, 0%)
      : (m = reRgbaInteger.exec(format)) ? rgba(m[1], m[2], m[3], m[4]) // rgba(255, 0, 0, 1)
      : (m = reRgbaPercent.exec(format)) ? rgba(m[1] * 255 / 100, m[2] * 255 / 100, m[3] * 255 / 100, m[4]) // rgb(100%, 0%, 0%, 1)
      : (m = reHslPercent.exec(format)) ? hsla(m[1], m[2] / 100, m[3] / 100, 1) // hsl(120, 50%, 50%)
      : (m = reHslaPercent.exec(format)) ? hsla(m[1], m[2] / 100, m[3] / 100, m[4]) // hsla(120, 50%, 50%, 1)
      : named.hasOwnProperty(format) ? rgbn(named[format]) // eslint-disable-line no-prototype-builtins
      : format === "transparent" ? new Rgb(NaN, NaN, NaN, 0)
      : null;
}

function rgbn(n) {
  return new Rgb(n >> 16 & 0xff, n >> 8 & 0xff, n & 0xff, 1);
}

function rgbn8(n) {
  return new Rgb(n >> 24 & 0xff, n >> 16 & 0xff, n >> 8 & 0xff, (n & 0xff) / 0xff);
}

function rgba(r, g, b, a) {
  if (a <= 0) r = g = b = NaN;
  return new Rgb(r, g, b, a);
}

export function rgbConvert(o) {
  if (!(o instanceof Color)) o = color(o);
  if (!o) return new Rgb;
  o = o.rgb();
  return new Rgb(o.r, o.g, o.b, o.opacity);
}

export function rgb(r, g, b, opacity) {
  return arguments.length === 1 ? rgbConvert(r) : new Rgb(r, g, b, opacity == null ? 1 : opacity);
}

export function Rgb(r, g, b, opacity) {
  this.r = +r;
  this.g = +g;
  this.b = +b;
  this.opacity = +opacity;
}

define(Rgb, rgb, extend(Color, {
  brighter: function(k) {
    k = k == null ? brighter : Math.pow(brighter, k);
    return new Rgb(this.r * k, this.g * k, this.b * k, this.opacity);
  },
  darker: function(k) {
    k = k == null ? darker : Math.pow(darker, k);
    return new Rgb(this.r * k, this.g * k, this.b * k, this.opacity);
  },
  rgb: function() {
    return this;
  },
  displayable: function() {
    return (-0.5 <= this.r && this.r < 255.5)
        && (-0.5 <= this.g && this.g < 255.5)
        && (-0.5 <= this.b && this.b < 255.5)
        && (0 <= this.opacity && this.opacity <= 1);
  },
  hex: rgb_formatHex, // Deprecated! Use color.formatHex.
  formatHex: rgb_formatHex,
  formatRgb: rgb_formatRgb,
  toString: rgb_formatRgb
}));

function rgb_formatHex() {
  return "#" + hex(this.r) + hex(this.g) + hex(this.b);
}

function rgb_formatRgb() {
  var a = this.opacity; a = isNaN(a) ? 1 : Math.max(0, Math.min(1, a));
  return (a === 1 ? "rgb(" : "rgba(")
      + Math.max(0, Math.min(255, Math.round(this.r) || 0)) + ", "
      + Math.max(0, Math.min(255, Math.round(this.g) || 0)) + ", "
      + Math.max(0, Math.min(255, Math.round(this.b) || 0))
      + (a === 1 ? ")" : ", " + a + ")");
}

function hex(value) {
  value = Math.max(0, Math.min(255, Math.round(value) || 0));
  return (value < 16 ? "0" : "") + value.toString(16);
}

function hsla(h, s, l, a) {
  if (a <= 0) h = s = l = NaN;
  else if (l <= 0 || l >= 1) h = s = NaN;
  else if (s <= 0) h = NaN;
  return new Hsl(h, s, l, a);
}

export function hslConvert(o) {
  if (o instanceof Hsl) return new Hsl(o.h, o.s, o.l, o.opacity);
  if (!(o instanceof Color)) o = color(o);
  if (!o) return new Hsl;
  if (o instanceof Hsl) return o;
  o = o.rgb();
  var r = o.r / 255,
      g = o.g / 255,
      b = o.b / 255,
      min = Math.min(r, g, b),
      max = Math.max(r, g, b),
      h = NaN,
      s = max - min,
      l = (max + min) / 2;
  if (s) {
    if (r === max) h = (g - b) / s + (g < b) * 6;
    else if (g === max) h = (b - r) / s + 2;
    else h = (r - g) / s + 4;
    s /= l < 0.5 ? max + min : 2 - max - min;
    h *= 60;
  } else {
    s = l > 0 && l < 1 ? 0 : h;
  }
  return new Hsl(h, s, l, o.opacity);
}

export function hsl(h, s, l, opacity) {
  return arguments.length === 1 ? hslConvert(h) : new Hsl(h, s, l, opacity == null ? 1 : opacity);
}

function Hsl(h, s, l, opacity) {
  this.h = +h;
  this.s = +s;
  this.l = +l;
  this.opacity = +opacity;
}

define(Hsl, hsl, extend(Color, {
  brighter: function(k) {
    k = k == null ? brighter : Math.pow(brighter, k);
    return new Hsl(this.h, this.s, this.l * k, this.opacity);
  },
  darker: function(k) {
    k = k == null ? darker : Math.pow(darker, k);
    return new Hsl(this.h, this.s, this.l * k, this.opacity);
  },
  rgb: function() {
    var h = this.h % 360 + (this.h < 0) * 360,
        s = isNaN(h) || isNaN(this.s) ? 0 : this.s,
        l = this.l,
        m2 = l + (l < 0.5 ? l : 1 - l) * s,
        m1 = 2 * l - m2;
    return new Rgb(
      hsl2rgb(h >= 240 ? h - 240 : h + 120, m1, m2),
      hsl2rgb(h, m1, m2),
      hsl2rgb(h < 120 ? h + 240 : h - 120, m1, m2),
      this.opacity
    );
  },
  displayable: function() {
    return (0 <= this.s && this.s <= 1 || isNaN(this.s))
        && (0 <= this.l && this.l <= 1)
        && (0 <= this.opacity && this.opacity <= 1);
  },
  formatHsl: function() {
    var a = this.opacity; a = isNaN(a) ? 1 : Math.max(0, Math.min(1, a));
    return (a === 1 ? "hsl(" : "hsla(")
        + (this.h || 0) + ", "
        + (this.s || 0) * 100 + "%, "
        + (this.l || 0) * 100 + "%"
        + (a === 1 ? ")" : ", " + a + ")");
  }
}));

/* From FvD 13.37, CSS Color Module Level 3 */
function hsl2rgb(h, m1, m2) {
  return (h < 60 ? m1 + (m2 - m1) * h / 60
      : h < 180 ? m2
      : h < 240 ? m1 + (m2 - m1) * (240 - h) / 60
      : m1) * 255;
}