duotone.php

<?php
/**
 * Duotone block support flag.
 *
 * @package gutenberg
 */

/**
 * Direct port of tinycolor's bound01 function, lightly simplified to maintain
 * consistency with tinycolor.
 *
 * @see https://github.com/bgrins/TinyColor
 *
 * @param  mixed $n   Number of unknown type.
 * @param  int   $max Upper value of the range to bound to.
 * @return float      Value in the range [0,1].
 */
function gutenberg_tinycolor_bound01( $n, $max ) {
	if ( 'string' === gettype( $n ) && false !== strpos( $n, '.' ) && 1 === (float) $n ) {
		$n = '100%';
	}

	$n = min( $max, max( 0, (float) $n ) );

	// Automatically convert percentage into number.
	if ( 'string' === gettype( $n ) && false !== strpos( $n, '%' ) ) {
		$n = (int) ( $n * $max ) / 100;
	}

	// Handle floating point rounding errors.
	if ( ( abs( $n - $max ) < 0.000001 ) ) {
		return 1.0;
	}

	// Convert into [0, 1] range if it isn't already.
	return ( $n % $max ) / (float) $max;
}

/**
 * Direct port of tinycolor's boundAlpha function to maintain consistency with
 * how tinycolor works.
 *
 * @see https://github.com/bgrins/TinyColor
 *
 * @param  mixed $n   Number of unknown type.
 * @return float      Value in the range [0,1].
 */
function gutenberg_tinycolor_bound_alpha( $n ) {
	if ( is_numeric( $n ) ) {
		$n = (float) $n;
		if ( $n >= 0 && $n <= 1 ) {
			return $n;
		}
	}
	return 1;
}

/**
 * Round and convert values of an RGB object.
 *
 * @see https://github.com/bgrins/TinyColor
 *
 * @param  array $rgb_color RGB object.
 * @return array            Rounded and converted RGB object.
 */
function gutenberg_tinycolor_rgb_to_rgb( $rgb_color ) {
	return array(
		'r' => gutenberg_tinycolor_bound01( $rgb_color['r'], 255 ) * 255,
		'g' => gutenberg_tinycolor_bound01( $rgb_color['g'], 255 ) * 255,
		'b' => gutenberg_tinycolor_bound01( $rgb_color['b'], 255 ) * 255,
	);
}

/**
 * Helper function for hsl to rgb conversion.
 *
 * @see https://github.com/bgrins/TinyColor
 *
 * @param  float $p first component.
 * @param  float $q second component.
 * @param  float $t third component.
 * @return float    R, G, or B component.
 */
function gutenberg_tinycolor_hue_to_rgb( $p, $q, $t ) {
	if ( $t < 0 ) {
		$t += 1;
	}
	if ( $t > 1 ) {
		$t -= 1;
	}
	if ( $t < 1 / 6 ) {
		return $p + ( $q - $p ) * 6 * $t;
	}
	if ( $t < 1 / 2 ) {
		return $q;
	}
	if ( $t < 2 / 3 ) {
		return $p + ( $q - $p ) * ( 2 / 3 - $t ) * 6;
	}
	return $p;
}

/**
 * Convert an HSL object to an RGB object with converted and rounded values.
 *
 * @see https://github.com/bgrins/TinyColor
 *
 * @param  array $hsl_color HSL object.
 * @return array            Rounded and converted RGB object.
 */
function gutenberg_tinycolor_hsl_to_rgb( $hsl_color ) {
	$h = gutenberg_tinycolor_bound01( $hsl_color['h'], 360 );
	$s = gutenberg_tinycolor_bound01( $hsl_color['s'], 100 );
	$l = gutenberg_tinycolor_bound01( $hsl_color['l'], 100 );

	if ( 0 === $s ) {
		// Achromatic.
		$r = $l;
		$g = $l;
		$b = $l;
	} else {
		$q = $l < 0.5 ? $l * ( 1 + $s ) : $l + $s - $l * $s;
		$p = 2 * $l - $q;
		$r = gutenberg_tinycolor_hue_to_rgb( $p, $q, $h + 1 / 3 );
		$g = gutenberg_tinycolor_hue_to_rgb( $p, $q, $h );
		$b = gutenberg_tinycolor_hue_to_rgb( $p, $q, $h - 1 / 3 );
	}

	return array(
		'r' => $r * 255,
		'g' => $g * 255,
		'b' => $b * 255,
	);
}

/**
 * Parses hex, hsl, and rgb CSS strings using the same regex as tinycolor v1.4.2
 * used in the JavaScript. Only colors output from react-color are implemented.
 *
 * @see https://github.com/bgrins/TinyColor
 * @see https://github.com/casesandberg/react-color/
 *
 * @param  string $color_str CSS color string.
 * @return array             RGB object.
 */
function gutenberg_tinycolor_string_to_rgb( $color_str ) {
	$color_str = strtolower( trim( $color_str ) );

	$css_integer = '[-\\+]?\\d+%?';
	$css_number  = '[-\\+]?\\d*\\.\\d+%?';

	$css_unit = '(?:' . $css_number . ')|(?:' . $css_integer . ')';

	$permissive_match3 = '[\\s|\\(]+(' . $css_unit . ')[,|\\s]+(' . $css_unit . ')[,|\\s]+(' . $css_unit . ')\\s*\\)?';
	$permissive_match4 = '[\\s|\\(]+(' . $css_unit . ')[,|\\s]+(' . $css_unit . ')[,|\\s]+(' . $css_unit . ')[,|\\s]+(' . $css_unit . ')\\s*\\)?';

	$rgb_regexp = '/^rgb' . $permissive_match3 . '$/';
	if ( preg_match( $rgb_regexp, $color_str, $match ) ) {
		$rgb = gutenberg_tinycolor_rgb_to_rgb(
			array(
				'r' => $match[1],
				'g' => $match[2],
				'b' => $match[3],
			)
		);

		$rgb['a'] = 1;

		return $rgb;
	}

	$rgba_regexp = '/^rgba' . $permissive_match4 . '$/';
	if ( preg_match( $rgba_regexp, $color_str, $match ) ) {
		$rgb = gutenberg_tinycolor_rgb_to_rgb(
			array(
				'r' => $match[1],
				'g' => $match[2],
				'b' => $match[3],
			)
		);

		$rgb['a'] = gutenberg_tinycolor_bound_alpha( $match[4] );

		return $rgb;
	}

	$hsl_regexp = '/^hsl' . $permissive_match3 . '$/';
	if ( preg_match( $hsl_regexp, $color_str, $match ) ) {
		$rgb = gutenberg_tinycolor_hsl_to_rgb(
			array(
				'h' => $match[1],
				's' => $match[2],
				'l' => $match[3],
			)
		);

		$rgb['a'] = 1;

		return $rgb;
	}

	$hsla_regexp = '/^hsla' . $permissive_match4 . '$/';
	if ( preg_match( $hsla_regexp, $color_str, $match ) ) {
		$rgb = gutenberg_tinycolor_hsl_to_rgb(
			array(
				'h' => $match[1],
				's' => $match[2],
				'l' => $match[3],
			)
		);

		$rgb['a'] = gutenberg_tinycolor_bound_alpha( $match[4] );

		return $rgb;
	}

	$hex8_regexp = '/^#?([0-9a-fA-F]{2})([0-9a-fA-F]{2})([0-9a-fA-F]{2})([0-9a-fA-F]{2})$/';
	if ( preg_match( $hex8_regexp, $color_str, $match ) ) {
		$rgb = gutenberg_tinycolor_rgb_to_rgb(
			array(
				'r' => base_convert( $match[1], 16, 10 ),
				'g' => base_convert( $match[2], 16, 10 ),
				'b' => base_convert( $match[3], 16, 10 ),
			)
		);

		$rgb['a'] = gutenberg_tinycolor_bound_alpha(
			base_convert( $match[4], 16, 10 ) / 255
		);

		return $rgb;
	}

	$hex6_regexp = '/^#?([0-9a-fA-F]{2})([0-9a-fA-F]{2})([0-9a-fA-F]{2})$/';
	if ( preg_match( $hex6_regexp, $color_str, $match ) ) {
		$rgb = gutenberg_tinycolor_rgb_to_rgb(
			array(
				'r' => base_convert( $match[1], 16, 10 ),
				'g' => base_convert( $match[2], 16, 10 ),
				'b' => base_convert( $match[3], 16, 10 ),
			)
		);

		$rgb['a'] = 1;

		return $rgb;
	}

	$hex4_regexp = '/^#?([0-9a-fA-F]{1})([0-9a-fA-F]{1})([0-9a-fA-F]{1})([0-9a-fA-F]{1})$/';
	if ( preg_match( $hex4_regexp, $color_str, $match ) ) {
		$rgb = gutenberg_tinycolor_rgb_to_rgb(
			array(
				'r' => base_convert( $match[1] . $match[1], 16, 10 ),
				'g' => base_convert( $match[2] . $match[2], 16, 10 ),
				'b' => base_convert( $match[3] . $match[3], 16, 10 ),
			)
		);

		$rgb['a'] = gutenberg_tinycolor_bound_alpha(
			base_convert( $match[4] . $match[4], 16, 10 ) / 255
		);

		return $rgb;
	}

	$hex3_regexp = '/^#?([0-9a-fA-F]{1})([0-9a-fA-F]{1})([0-9a-fA-F]{1})$/';
	if ( preg_match( $hex3_regexp, $color_str, $match ) ) {
		$rgb = gutenberg_tinycolor_rgb_to_rgb(
			array(
				'r' => base_convert( $match[1] . $match[1], 16, 10 ),
				'g' => base_convert( $match[2] . $match[2], 16, 10 ),
				'b' => base_convert( $match[3] . $match[3], 16, 10 ),
			)
		);

		$rgb['a'] = 1;

		return $rgb;
	}

	// The JS color picker considers the string "transparent" to be a hex value,
	// so we need to handle it here as a special case.
	if ( 'transparent' === $color_str ) {
		return array(
			'r' => 0,
			'g' => 0,
			'b' => 0,
			'a' => 0,
		);
	}
}


/**
 * Registers the style and colors block attributes for block types that support it.
 *
 * @param WP_Block_Type $block_type Block Type.
 */
function gutenberg_register_duotone_support( $block_type ) {
	$has_duotone_support = false;
	if ( property_exists( $block_type, 'supports' ) ) {
		$has_duotone_support = _wp_array_get( $block_type->supports, array( 'color', '__experimentalDuotone' ), false );
	}

	if ( $has_duotone_support ) {
		if ( ! $block_type->attributes ) {
			$block_type->attributes = array();
		}

		if ( ! array_key_exists( 'style', $block_type->attributes ) ) {
			$block_type->attributes['style'] = array(
				'type' => 'object',
			);
		}
	}
}

/**
 * Renders the duotone filter SVG and returns the CSS filter property to
 * reference the rendered SVG.
 *
 * @param array $preset Duotone preset value as seen in theme.json.
 *
 * @return string Duotone CSS filter property.
 */
function gutenberg_render_duotone_filter_preset( $preset ) {
	$duotone_id     = $preset['slug'];
	$duotone_colors = $preset['colors'];
	$filter_id      = 'wp-duotone-' . $duotone_id;
	$duotone_values = array(
		'r' => array(),
		'g' => array(),
		'b' => array(),
		'a' => array(),
	);
	foreach ( $duotone_colors as $color_str ) {
		$color = gutenberg_tinycolor_string_to_rgb( $color_str );

		$duotone_values['r'][] = $color['r'] / 255;
		$duotone_values['g'][] = $color['g'] / 255;
		$duotone_values['b'][] = $color['b'] / 255;
		$duotone_values['a'][] = $color['a'];
	}

	ob_start();

	?>

	<svg
		xmlns="http://www.w3.org/2000/svg"
		viewBox="0 0 0 0"
		width="0"
		height="0"
		focusable="false"
		role="none"
		style="visibility: hidden; position: absolute; left: -9999px; overflow: hidden;"
	>
		<defs>
			<filter id="<?php echo esc_attr( $filter_id ); ?>">
				<feColorMatrix
					color-interpolation-filters="sRGB"
					type="matrix"
					values="
						.299 .587 .114 0 0
						.299 .587 .114 0 0
						.299 .587 .114 0 0
						.299 .587 .114 0 0
					"
				/>
				<feComponentTransfer color-interpolation-filters="sRGB" >
					<feFuncR type="table" tableValues="<?php echo esc_attr( implode( ' ', $duotone_values['r'] ) ); ?>" />
					<feFuncG type="table" tableValues="<?php echo esc_attr( implode( ' ', $duotone_values['g'] ) ); ?>" />
					<feFuncB type="table" tableValues="<?php echo esc_attr( implode( ' ', $duotone_values['b'] ) ); ?>" />
					<feFuncA type="table" tableValues="<?php echo esc_attr( implode( ' ', $duotone_values['a'] ) ); ?>" />
				</feComponentTransfer>
				<feComposite in2="SourceGraphic" operator="in" />
			</filter>
		</defs>
	</svg>

	<?php

	$svg = ob_get_clean();

	if ( ! defined( 'SCRIPT_DEBUG' ) || ! SCRIPT_DEBUG ) {
		// Clean up the whitespace.
		$svg = preg_replace( "/[\r\n\t ]+/", ' ', $svg );
		$svg = preg_replace( '/> </', '><', $svg );
		$svg = trim( $svg );
	}

	add_action(
		// SVG filters won't render at all in the head of a document and
		// Safari incorrectly renders SVG filters in the footer, so the
		// beginning of the body seems to be the safest place to render.
		'wp_body_open',
		function () use ( $svg ) {
			echo $svg;
		}
	);

	return "url('#" . $filter_id . "')";
}

/**
 * Render out the duotone stylesheet and SVG.
 *
 * @param  string $block_content Rendered block content.
 * @param  array  $block         Block object.
 * @return string                Filtered block content.
 */
function gutenberg_render_duotone_support( $block_content, $block ) {
	$block_type = WP_Block_Type_Registry::get_instance()->get_registered( $block['blockName'] );

	$duotone_support = false;
	if ( $block_type && property_exists( $block_type, 'supports' ) ) {
		$duotone_support = _wp_array_get( $block_type->supports, array( 'color', '__experimentalDuotone' ), false );
	}

	$has_duotone_attribute = isset( $block['attrs']['style']['color']['duotone'] );

	if (
		! $duotone_support ||
		! $has_duotone_attribute
	) {
		return $block_content;
	}

	$filter_preset   = array(
		'slug'   => uniqid(),
		'colors' => $block['attrs']['style']['color']['duotone'],
	);
	$filter_property = gutenberg_render_duotone_filter_preset( $filter_preset );
	$filter_id       = 'wp-duotone-' . $filter_preset['slug'];

	$scope     = '.' . $filter_id;
	$selectors = explode( ',', $duotone_support );
	$scoped    = array();
	foreach ( $selectors as $sel ) {
		$scoped[] = $scope . ' ' . trim( $sel );
	}
	$selector = implode( ', ', $scoped );

	// !important is needed because these styles render before global styles,
	// and they should be overriding the duotone filters set by global styles.
	$filter_style = defined( 'SCRIPT_DEBUG' ) && SCRIPT_DEBUG
		? $selector . " {\n\tfilter: " . $filter_property . " !important;\n}\n"
		: $selector . '{filter:' . $filter_property . ' !important;}';

	wp_register_style( $filter_id, false, array(), true, true );
	wp_add_inline_style( $filter_id, $filter_style );
	wp_enqueue_style( $filter_id );

	// Like the layout hook, this assumes the hook only applies to blocks with a single wrapper.
	return preg_replace(
		'/' . preg_quote( 'class="', '/' ) . '/',
		'class="' . $filter_id . ' ',
		$block_content,
		1
	);
}

// Register the block support.
WP_Block_Supports::get_instance()->register(
	'duotone',
	array(
		'register_attribute' => 'gutenberg_register_duotone_support',
	)
);

// Remove WordPress core filter to avoid rendering duplicate support elements.
remove_filter( 'render_block', 'wp_render_duotone_support', 10, 2 );
add_filter( 'render_block', 'gutenberg_render_duotone_support', 10, 2 );