1128 lines
31 KiB
JavaScript
1128 lines
31 KiB
JavaScript
/* This Source Code Form is subject to the terms of the Mozilla Public
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* License, v. 2.0. If a copy of the MPL was not distributed with this
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* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
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"use strict";
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const Services = require("Services");
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const {CSS_ANGLEUNIT} = require("devtools/shared/css/properties-db");
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const {getAngleValueInDegrees} = require("devtools/shared/css/parsing-utils");
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const {getCSSLexer} = require("devtools/shared/css/lexer");
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const {cssColors} = require("devtools/shared/css/color-db");
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const COLOR_UNIT_PREF = "devtools.defaultColorUnit";
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const SPECIALVALUES = new Set([
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"currentcolor",
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"initial",
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"inherit",
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"transparent",
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"unset"
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]);
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/**
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* This module is used to convert between various color types.
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*
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* Usage:
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* let {colorUtils} = require("devtools/shared/css/color");
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* let color = new colorUtils.CssColor("red");
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* // In order to support css-color-4 color function, pass true to the
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* // second argument.
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* // e.g.
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* // let color = new colorUtils.CssColor("red", true);
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*
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* color.authored === "red"
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* color.hasAlpha === false
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* color.valid === true
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* color.transparent === false // transparent has a special status.
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* color.name === "red" // returns hex when no name available.
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* color.hex === "#f00" // returns shortHex when available else returns
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* longHex. If alpha channel is present then we
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* return this.alphaHex if available,
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* or this.longAlphaHex if not.
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* color.alphaHex === "#f00f" // returns short alpha hex when available
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* else returns longAlphaHex.
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* color.longHex === "#ff0000" // If alpha channel is present then we return
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* this.longAlphaHex.
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* color.longAlphaHex === "#ff0000ff"
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* color.rgb === "rgb(255, 0, 0)" // If alpha channel is present
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* // then we return this.rgba.
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* color.rgba === "rgba(255, 0, 0, 1)"
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* color.hsl === "hsl(0, 100%, 50%)"
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* color.hsla === "hsla(0, 100%, 50%, 1)" // If alpha channel is present
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* then we return this.rgba.
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*
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* color.toString() === "#f00"; // Outputs the color type determined in the
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* COLOR_UNIT_PREF constant (above).
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* // Color objects can be reused
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* color.newColor("green") === "#0f0"; // true
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*
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* Valid values for COLOR_UNIT_PREF are contained in CssColor.COLORUNIT.
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*/
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function CssColor(colorValue, supportsCssColor4ColorFunction = false) {
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this.newColor(colorValue);
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this.cssColor4 = supportsCssColor4ColorFunction;
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}
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module.exports.colorUtils = {
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CssColor: CssColor,
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rgbToHsl: rgbToHsl,
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setAlpha: setAlpha,
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classifyColor: classifyColor,
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rgbToColorName: rgbToColorName,
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colorToRGBA: colorToRGBA,
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isValidCSSColor: isValidCSSColor,
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};
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/**
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* Values used in COLOR_UNIT_PREF
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*/
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CssColor.COLORUNIT = {
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"authored": "authored",
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"hex": "hex",
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"name": "name",
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"rgb": "rgb",
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"hsl": "hsl"
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};
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CssColor.prototype = {
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_colorUnit: null,
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_colorUnitUppercase: false,
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// The value as-authored.
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authored: null,
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// A lower-cased copy of |authored|.
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lowerCased: null,
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// Whether the value should be parsed using css-color-4 rules.
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cssColor4: false,
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_setColorUnitUppercase: function (color) {
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// Specifically exclude the case where the color is
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// case-insensitive. This makes it so that "#000" isn't
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// considered "upper case" for the purposes of color cycling.
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this._colorUnitUppercase = (color === color.toUpperCase()) &&
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(color !== color.toLowerCase());
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},
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get colorUnit() {
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if (this._colorUnit === null) {
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let defaultUnit = Services.prefs.getCharPref(COLOR_UNIT_PREF);
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this._colorUnit = CssColor.COLORUNIT[defaultUnit];
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this._setColorUnitUppercase(this.authored);
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}
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return this._colorUnit;
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},
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set colorUnit(unit) {
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this._colorUnit = unit;
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},
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/**
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* If the current color unit pref is "authored", then set the
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* default color unit from the given color. Otherwise, leave the
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* color unit untouched.
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*
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* @param {String} color The color to use
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*/
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setAuthoredUnitFromColor: function (color) {
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if (Services.prefs.getCharPref(COLOR_UNIT_PREF) ===
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CssColor.COLORUNIT.authored) {
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this._colorUnit = classifyColor(color);
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this._setColorUnitUppercase(color);
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}
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},
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get hasAlpha() {
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if (!this.valid) {
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return false;
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}
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return this._getRGBATuple().a !== 1;
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},
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get valid() {
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return isValidCSSColor(this.authored, this.cssColor4);
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},
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/**
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* Return true for all transparent values e.g. rgba(0, 0, 0, 0).
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*/
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get transparent() {
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try {
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let tuple = this._getRGBATuple();
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return !(tuple.r || tuple.g || tuple.b || tuple.a);
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} catch (e) {
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return false;
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}
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},
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get specialValue() {
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return SPECIALVALUES.has(this.lowerCased) ? this.authored : null;
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},
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get name() {
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let invalidOrSpecialValue = this._getInvalidOrSpecialValue();
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if (invalidOrSpecialValue !== false) {
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return invalidOrSpecialValue;
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}
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try {
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let tuple = this._getRGBATuple();
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if (tuple.a !== 1) {
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return this.hex;
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}
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let {r, g, b} = tuple;
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return rgbToColorName(r, g, b);
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} catch (e) {
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return this.hex;
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}
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},
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get hex() {
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let invalidOrSpecialValue = this._getInvalidOrSpecialValue();
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if (invalidOrSpecialValue !== false) {
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return invalidOrSpecialValue;
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}
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if (this.hasAlpha) {
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return this.alphaHex;
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}
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let hex = this.longHex;
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if (hex.charAt(1) == hex.charAt(2) &&
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hex.charAt(3) == hex.charAt(4) &&
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hex.charAt(5) == hex.charAt(6)) {
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hex = "#" + hex.charAt(1) + hex.charAt(3) + hex.charAt(5);
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}
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return hex;
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},
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get alphaHex() {
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let invalidOrSpecialValue = this._getInvalidOrSpecialValue();
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if (invalidOrSpecialValue !== false) {
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return invalidOrSpecialValue;
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}
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let alphaHex = this.longAlphaHex;
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if (alphaHex.charAt(1) == alphaHex.charAt(2) &&
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alphaHex.charAt(3) == alphaHex.charAt(4) &&
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alphaHex.charAt(5) == alphaHex.charAt(6) &&
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alphaHex.charAt(7) == alphaHex.charAt(8)) {
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alphaHex = "#" + alphaHex.charAt(1) + alphaHex.charAt(3) +
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alphaHex.charAt(5) + alphaHex.charAt(7);
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}
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return alphaHex;
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},
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get longHex() {
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let invalidOrSpecialValue = this._getInvalidOrSpecialValue();
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if (invalidOrSpecialValue !== false) {
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return invalidOrSpecialValue;
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}
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if (this.hasAlpha) {
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return this.longAlphaHex;
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}
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let tuple = this._getRGBATuple();
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return "#" + ((1 << 24) + (tuple.r << 16) + (tuple.g << 8) +
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(tuple.b << 0)).toString(16).substr(-6);
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},
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get longAlphaHex() {
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let invalidOrSpecialValue = this._getInvalidOrSpecialValue();
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if (invalidOrSpecialValue !== false) {
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return invalidOrSpecialValue;
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}
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let tuple = this._getRGBATuple();
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return "#" + ((1 << 24) + (tuple.r << 16) + (tuple.g << 8) +
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(tuple.b << 0)).toString(16).substr(-6) +
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Math.round(tuple.a * 255).toString(16).padEnd(2, "0");
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},
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get rgb() {
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let invalidOrSpecialValue = this._getInvalidOrSpecialValue();
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if (invalidOrSpecialValue !== false) {
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return invalidOrSpecialValue;
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}
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if (!this.hasAlpha) {
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if (this.lowerCased.startsWith("rgb(")) {
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// The color is valid and begins with rgb(.
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return this.authored;
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}
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let tuple = this._getRGBATuple();
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return "rgb(" + tuple.r + ", " + tuple.g + ", " + tuple.b + ")";
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}
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return this.rgba;
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},
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get rgba() {
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let invalidOrSpecialValue = this._getInvalidOrSpecialValue();
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if (invalidOrSpecialValue !== false) {
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return invalidOrSpecialValue;
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}
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if (this.lowerCased.startsWith("rgba(")) {
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// The color is valid and begins with rgba(.
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return this.authored;
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}
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let components = this._getRGBATuple();
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return "rgba(" + components.r + ", " +
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components.g + ", " +
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components.b + ", " +
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components.a + ")";
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},
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get hsl() {
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let invalidOrSpecialValue = this._getInvalidOrSpecialValue();
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if (invalidOrSpecialValue !== false) {
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return invalidOrSpecialValue;
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}
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if (this.lowerCased.startsWith("hsl(")) {
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// The color is valid and begins with hsl(.
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return this.authored;
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}
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if (this.hasAlpha) {
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return this.hsla;
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}
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return this._hsl();
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},
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get hsla() {
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let invalidOrSpecialValue = this._getInvalidOrSpecialValue();
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if (invalidOrSpecialValue !== false) {
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return invalidOrSpecialValue;
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}
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if (this.lowerCased.startsWith("hsla(")) {
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// The color is valid and begins with hsla(.
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return this.authored;
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}
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if (this.hasAlpha) {
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let a = this._getRGBATuple().a;
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return this._hsl(a);
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}
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return this._hsl(1);
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},
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/**
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* Check whether the current color value is in the special list e.g.
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* transparent or invalid.
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*
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* @return {String|Boolean}
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* - If the current color is a special value e.g. "transparent" then
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* return the color.
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* - If the color is invalid return an empty string.
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* - If the color is a regular color e.g. #F06 so we return false
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* to indicate that the color is neither invalid or special.
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*/
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_getInvalidOrSpecialValue: function () {
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if (this.specialValue) {
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return this.specialValue;
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}
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if (!this.valid) {
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return "";
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}
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return false;
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},
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/**
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* Change color
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*
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* @param {String} color
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* Any valid color string
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*/
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newColor: function (color) {
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// Store a lower-cased version of the color to help with format
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// testing. The original text is kept as well so it can be
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// returned when needed.
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this.lowerCased = color.toLowerCase();
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this.authored = color;
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this._setColorUnitUppercase(color);
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return this;
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},
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nextColorUnit: function () {
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// Reorder the formats array to have the current format at the
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// front so we can cycle through.
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let formats = ["hex", "hsl", "rgb", "name"];
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let currentFormat = classifyColor(this.toString());
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let putOnEnd = formats.splice(0, formats.indexOf(currentFormat));
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formats = formats.concat(putOnEnd);
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let currentDisplayedColor = this[formats[0]];
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for (let format of formats) {
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if (this[format].toLowerCase() !== currentDisplayedColor.toLowerCase()) {
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this.colorUnit = CssColor.COLORUNIT[format];
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break;
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}
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}
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return this.toString();
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},
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/**
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* Return a string representing a color of type defined in COLOR_UNIT_PREF.
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*/
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toString: function () {
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let color;
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switch (this.colorUnit) {
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case CssColor.COLORUNIT.authored:
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color = this.authored;
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break;
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case CssColor.COLORUNIT.hex:
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color = this.hex;
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break;
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case CssColor.COLORUNIT.hsl:
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color = this.hsl;
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break;
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case CssColor.COLORUNIT.name:
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color = this.name;
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break;
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case CssColor.COLORUNIT.rgb:
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color = this.rgb;
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break;
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default:
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color = this.rgb;
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}
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if (this._colorUnitUppercase &&
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this.colorUnit != CssColor.COLORUNIT.authored) {
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color = color.toUpperCase();
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}
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return color;
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},
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/**
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* Returns a RGBA 4-Tuple representation of a color or transparent as
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* appropriate.
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*/
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_getRGBATuple: function () {
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let tuple = colorToRGBA(this.authored, this.cssColor4);
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tuple.a = parseFloat(tuple.a.toFixed(1));
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return tuple;
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},
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_hsl: function (maybeAlpha) {
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if (this.lowerCased.startsWith("hsl(") && maybeAlpha === undefined) {
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// We can use it as-is.
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return this.authored;
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}
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let {r, g, b} = this._getRGBATuple();
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let [h, s, l] = rgbToHsl([r, g, b]);
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if (maybeAlpha !== undefined) {
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return "hsla(" + h + ", " + s + "%, " + l + "%, " + maybeAlpha + ")";
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}
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return "hsl(" + h + ", " + s + "%, " + l + "%)";
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},
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/**
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* This method allows comparison of CssColor objects using ===.
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*/
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valueOf: function () {
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return this.rgba;
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},
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};
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/**
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* Convert rgb value to hsl
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*
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* @param {array} rgb
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* Array of rgb values
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* @return {array}
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* Array of hsl values.
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*/
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function rgbToHsl([r, g, b]) {
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r = r / 255;
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g = g / 255;
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b = b / 255;
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let max = Math.max(r, g, b);
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let min = Math.min(r, g, b);
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let h;
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let s;
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let l = (max + min) / 2;
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if (max == min) {
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h = s = 0;
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} else {
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let d = max - min;
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s = l > 0.5 ? d / (2 - max - min) : d / (max + min);
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switch (max) {
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case r:
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h = ((g - b) / d) % 6;
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break;
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case g:
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h = (b - r) / d + 2;
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break;
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case b:
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h = (r - g) / d + 4;
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break;
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}
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h *= 60;
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if (h < 0) {
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h += 360;
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}
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}
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return [roundTo(h, 1), roundTo(s * 100, 1), roundTo(l * 100, 1)];
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}
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function roundTo(number, digits) {
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const multiplier = Math.pow(10, digits);
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return Math.round(number * multiplier) / multiplier;
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}
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/**
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* Takes a color value of any type (hex, hsl, hsla, rgb, rgba)
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* and an alpha value to generate an rgba string with the correct
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* alpha value.
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*
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* @param {String} colorValue
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* Color in the form of hex, hsl, hsla, rgb, rgba.
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* @param {Number} alpha
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* Alpha value for the color, between 0 and 1.
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* @param {Boolean} useCssColor4ColorFunction
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* use css-color-4 color function or not.
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* @return {String}
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* Converted color with `alpha` value in rgba form.
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*/
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function setAlpha(colorValue, alpha, useCssColor4ColorFunction = false) {
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let color = new CssColor(colorValue, useCssColor4ColorFunction);
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|
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// Throw if the color supplied is not valid.
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if (!color.valid) {
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throw new Error("Invalid color.");
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}
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|
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// If an invalid alpha valid, just set to 1.
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if (!(alpha >= 0 && alpha <= 1)) {
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alpha = 1;
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}
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let { r, g, b } = color._getRGBATuple();
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return "rgba(" + r + ", " + g + ", " + b + ", " + alpha + ")";
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}
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|
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/**
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* Given a color, classify its type as one of the possible color
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* units, as known by |CssColor.colorUnit|.
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*
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* @param {String} value
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* The color, in any form accepted by CSS.
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* @return {String}
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* The color classification, one of "rgb", "hsl", "hex", or "name".
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*/
|
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function classifyColor(value) {
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value = value.toLowerCase();
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if (value.startsWith("rgb(") || value.startsWith("rgba(")) {
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return CssColor.COLORUNIT.rgb;
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} else if (value.startsWith("hsl(") || value.startsWith("hsla(")) {
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return CssColor.COLORUNIT.hsl;
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} else if (/^#[0-9a-f]+$/.exec(value)) {
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return CssColor.COLORUNIT.hex;
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}
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return CssColor.COLORUNIT.name;
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}
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|
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// This holds a map from colors back to color names for use by
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// rgbToColorName.
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var cssRGBMap;
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|
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/**
|
|
* Given a color, return its name, if it has one. Throws an exception
|
|
* if the color does not have a name.
|
|
*
|
|
* @param {Number} r, g, b The color components.
|
|
* @return {String} the name of the color
|
|
*/
|
|
function rgbToColorName(r, g, b) {
|
|
if (!cssRGBMap) {
|
|
cssRGBMap = {};
|
|
for (let name in cssColors) {
|
|
let key = JSON.stringify(cssColors[name]);
|
|
if (!(key in cssRGBMap)) {
|
|
cssRGBMap[key] = name;
|
|
}
|
|
}
|
|
}
|
|
let value = cssRGBMap[JSON.stringify([r, g, b, 1])];
|
|
if (!value) {
|
|
throw new Error("no such color");
|
|
}
|
|
return value;
|
|
}
|
|
|
|
// Translated from nsColor.cpp.
|
|
function _hslValue(m1, m2, h) {
|
|
if (h < 0.0) {
|
|
h += 1.0;
|
|
}
|
|
if (h > 1.0) {
|
|
h -= 1.0;
|
|
}
|
|
if (h < 1.0 / 6.0) {
|
|
return m1 + (m2 - m1) * h * 6.0;
|
|
}
|
|
if (h < 1.0 / 2.0) {
|
|
return m2;
|
|
}
|
|
if (h < 2.0 / 3.0) {
|
|
return m1 + (m2 - m1) * (2.0 / 3.0 - h) * 6.0;
|
|
}
|
|
return m1;
|
|
}
|
|
|
|
// Translated from nsColor.cpp. All three values are expected to be
|
|
// in the range 0-1.
|
|
function hslToRGB([h, s, l]) {
|
|
let r, g, b;
|
|
let m1, m2;
|
|
if (l <= 0.5) {
|
|
m2 = l * (s + 1);
|
|
} else {
|
|
m2 = l + s - l * s;
|
|
}
|
|
m1 = l * 2 - m2;
|
|
r = Math.round(255 * _hslValue(m1, m2, h + 1.0 / 3.0));
|
|
g = Math.round(255 * _hslValue(m1, m2, h));
|
|
b = Math.round(255 * _hslValue(m1, m2, h - 1.0 / 3.0));
|
|
return [r, g, b];
|
|
}
|
|
|
|
/**
|
|
* A helper function to convert a hex string like "F0C" or "F0C8" to a color.
|
|
*
|
|
* @param {String} name the color string
|
|
* @return {Object} an object of the form {r, g, b, a}; or null if the
|
|
* name was not a valid color
|
|
*/
|
|
function hexToRGBA(name) {
|
|
let r, g, b, a = 1;
|
|
|
|
if (name.length === 3) {
|
|
// short hex string (e.g. F0C)
|
|
r = parseInt(name.charAt(0) + name.charAt(0), 16);
|
|
g = parseInt(name.charAt(1) + name.charAt(1), 16);
|
|
b = parseInt(name.charAt(2) + name.charAt(2), 16);
|
|
} else if (name.length === 4) {
|
|
// short alpha hex string (e.g. F0CA)
|
|
r = parseInt(name.charAt(0) + name.charAt(0), 16);
|
|
g = parseInt(name.charAt(1) + name.charAt(1), 16);
|
|
b = parseInt(name.charAt(2) + name.charAt(2), 16);
|
|
a = parseInt(name.charAt(3) + name.charAt(3), 16) / 255;
|
|
} else if (name.length === 6) {
|
|
// hex string (e.g. FD01CD)
|
|
r = parseInt(name.charAt(0) + name.charAt(1), 16);
|
|
g = parseInt(name.charAt(2) + name.charAt(3), 16);
|
|
b = parseInt(name.charAt(4) + name.charAt(5), 16);
|
|
} else if (name.length === 8) {
|
|
// alpha hex string (e.g. FD01CDAB)
|
|
r = parseInt(name.charAt(0) + name.charAt(1), 16);
|
|
g = parseInt(name.charAt(2) + name.charAt(3), 16);
|
|
b = parseInt(name.charAt(4) + name.charAt(5), 16);
|
|
a = parseInt(name.charAt(6) + name.charAt(7), 16) / 255;
|
|
} else {
|
|
return null;
|
|
}
|
|
a = Math.round(a * 10) / 10;
|
|
return {r, g, b, a};
|
|
}
|
|
|
|
/**
|
|
* A helper function to clamp a value.
|
|
*
|
|
* @param {Number} value The value to clamp
|
|
* @param {Number} min The minimum value
|
|
* @param {Number} max The maximum value
|
|
* @return {Number} A value between min and max
|
|
*/
|
|
function clamp(value, min, max) {
|
|
if (value < min) {
|
|
value = min;
|
|
}
|
|
if (value > max) {
|
|
value = max;
|
|
}
|
|
return value;
|
|
}
|
|
|
|
/**
|
|
* A helper function to get a token from a lexer, skipping comments
|
|
* and whitespace.
|
|
*
|
|
* @param {CSSLexer} lexer The lexer
|
|
* @return {CSSToken} The next non-whitespace, non-comment token; or
|
|
* null at EOF.
|
|
*/
|
|
function getToken(lexer) {
|
|
if (lexer._hasPushBackToken) {
|
|
lexer._hasPushBackToken = false;
|
|
return lexer._currentToken;
|
|
}
|
|
|
|
while (true) {
|
|
let token = lexer.nextToken();
|
|
if (!token || (token.tokenType !== "comment" &&
|
|
token.tokenType !== "whitespace")) {
|
|
lexer._currentToken = token;
|
|
return token;
|
|
}
|
|
}
|
|
}
|
|
|
|
/**
|
|
* A helper function to put a token back to lexer for the next call of
|
|
* getToken().
|
|
*
|
|
* @param {CSSLexer} lexer The lexer
|
|
*/
|
|
function unGetToken(lexer) {
|
|
if (lexer._hasPushBackToken) {
|
|
throw new Error("Double pushback.");
|
|
}
|
|
lexer._hasPushBackToken = true;
|
|
}
|
|
|
|
/**
|
|
* A helper function that checks if the next token matches symbol.
|
|
* If so, reads the token and returns true. If not, pushes the
|
|
* token back and returns false.
|
|
*
|
|
* @param {CSSLexer} lexer The lexer.
|
|
* @param {String} symbol The symbol.
|
|
* @return {Boolean} The expect symbol is parsed or not.
|
|
*/
|
|
function expectSymbol(lexer, symbol) {
|
|
let token = getToken(lexer);
|
|
if (!token) {
|
|
return false;
|
|
}
|
|
|
|
if (token.tokenType !== "symbol" || token.text !== symbol) {
|
|
unGetToken(lexer);
|
|
return false;
|
|
}
|
|
|
|
return true;
|
|
}
|
|
|
|
const COLOR_COMPONENT_TYPE = {
|
|
"integer": "integer",
|
|
"number": "number",
|
|
"percentage": "percentage",
|
|
};
|
|
|
|
/**
|
|
* Parse a <integer> or a <number> or a <percentage> color component. If
|
|
* |separator| is provided (not an empty string ""), this function will also
|
|
* attempt to parse that character after parsing the color component. The range
|
|
* of output component value is [0, 1] if the component type is percentage.
|
|
* Otherwise, the range is [0, 255].
|
|
*
|
|
* @param {CSSLexer} lexer The lexer.
|
|
* @param {COLOR_COMPONENT_TYPE} type The color component type.
|
|
* @param {String} separator The separator.
|
|
* @param {Array} colorArray [out] The parsed color component will push into this array.
|
|
* @return {Boolean} Return false on error.
|
|
*/
|
|
function parseColorComponent(lexer, type, separator, colorArray) {
|
|
let token = getToken(lexer);
|
|
|
|
if (!token) {
|
|
return false;
|
|
}
|
|
|
|
switch (type) {
|
|
case COLOR_COMPONENT_TYPE.integer:
|
|
if (token.tokenType !== "number" || !token.isInteger) {
|
|
return false;
|
|
}
|
|
break;
|
|
case COLOR_COMPONENT_TYPE.number:
|
|
if (token.tokenType !== "number") {
|
|
return false;
|
|
}
|
|
break;
|
|
case COLOR_COMPONENT_TYPE.percentage:
|
|
if (token.tokenType !== "percentage") {
|
|
return false;
|
|
}
|
|
break;
|
|
default:
|
|
throw new Error("Invalid color component type.");
|
|
}
|
|
|
|
let colorComponent = 0;
|
|
if (type === COLOR_COMPONENT_TYPE.percentage) {
|
|
colorComponent = clamp(token.number, 0, 1);
|
|
} else {
|
|
colorComponent = clamp(token.number, 0, 255);
|
|
}
|
|
|
|
if (separator !== "" && !expectSymbol(lexer, separator)) {
|
|
return false;
|
|
}
|
|
|
|
colorArray.push(colorComponent);
|
|
|
|
return true;
|
|
}
|
|
|
|
/**
|
|
* Parse an optional [ separator <alpha-value> ] expression, followed by a
|
|
* close-parenthesis, at the end of a css color function (e.g. rgba() or hsla()).
|
|
* If this function simply encounters a close-parenthesis (without the
|
|
* [ separator <alpha-value> ]), it will still succeed. Then put a fully-opaque
|
|
* alpha value into the colorArray. The range of output alpha value is [0, 1].
|
|
*
|
|
* @param {CSSLexer} lexer The lexer
|
|
* @param {String} separator The separator.
|
|
* @param {Array} colorArray [out] The parsed color component will push into this array.
|
|
* @return {Boolean} Return false on error.
|
|
*/
|
|
function parseColorOpacityAndCloseParen(lexer, separator, colorArray) {
|
|
// The optional [separator <alpha-value>] was omitted, so set the opacity
|
|
// to a fully-opaque value '1.0' and return success.
|
|
if (expectSymbol(lexer, ")")) {
|
|
colorArray.push(1);
|
|
return true;
|
|
}
|
|
|
|
if (!expectSymbol(lexer, separator)) {
|
|
return false;
|
|
}
|
|
|
|
let token = getToken(lexer);
|
|
if (!token) {
|
|
return false;
|
|
}
|
|
|
|
// <number> or <percentage>
|
|
if (token.tokenType !== "number" && token.tokenType !== "percentage") {
|
|
return false;
|
|
}
|
|
|
|
if (!expectSymbol(lexer, ")")) {
|
|
return false;
|
|
}
|
|
|
|
colorArray.push(clamp(token.number, 0, 1));
|
|
|
|
return true;
|
|
}
|
|
|
|
/**
|
|
* Parse a hue value.
|
|
* <hue> = <number> | <angle>
|
|
*
|
|
* @param {CSSLexer} lexer The lexer
|
|
* @param {Array} colorArray [out] The parsed color component will push into this array.
|
|
* @return {Boolean} Return false on error.
|
|
*/
|
|
function parseHue(lexer, colorArray) {
|
|
let token = getToken(lexer);
|
|
|
|
if (!token) {
|
|
return false;
|
|
}
|
|
|
|
let val = 0;
|
|
if (token.tokenType === "number") {
|
|
val = token.number;
|
|
} else if (token.tokenType === "dimension" && token.text in CSS_ANGLEUNIT) {
|
|
val = getAngleValueInDegrees(token.number, token.text);
|
|
} else {
|
|
return false;
|
|
}
|
|
|
|
val = val / 360.0;
|
|
colorArray.push(val - Math.floor(val));
|
|
|
|
return true;
|
|
}
|
|
|
|
/**
|
|
* A helper function to parse the color components of hsl()/hsla() function.
|
|
* hsl() and hsla() are now aliases.
|
|
*
|
|
* @param {CSSLexer} lexer The lexer
|
|
* @return {Array} An array of the form [r,g,b,a]; or null on error.
|
|
*/
|
|
function parseHsl(lexer) {
|
|
// comma-less expression:
|
|
// hsl() = hsl( <hue> <saturation> <lightness> [ / <alpha-value> ]? )
|
|
// the expression with comma:
|
|
// hsl() = hsl( <hue>, <saturation>, <lightness>, <alpha-value>? )
|
|
//
|
|
// <hue> = <number> | <angle>
|
|
// <alpha-value> = <number> | <percentage>
|
|
|
|
const commaSeparator = ",";
|
|
let hsl = [];
|
|
let a = [];
|
|
|
|
// Parse hue.
|
|
if (!parseHue(lexer, hsl)) {
|
|
return null;
|
|
}
|
|
|
|
// Look for a comma separator after "hue" component to determine if the
|
|
// expression is comma-less or not.
|
|
let hasComma = expectSymbol(lexer, commaSeparator);
|
|
|
|
// Parse saturation, lightness and opacity.
|
|
// The saturation and lightness are <percentage>, so reuse the <percentage>
|
|
// version of parseColorComponent function for them. No need to check the
|
|
// separator after 'lightness'. It will be checked in opacity value parsing.
|
|
let separatorBeforeAlpha = hasComma ? commaSeparator : "/";
|
|
if (parseColorComponent(lexer, COLOR_COMPONENT_TYPE.percentage,
|
|
hasComma ? commaSeparator : "", hsl) &&
|
|
parseColorComponent(lexer, COLOR_COMPONENT_TYPE.percentage, "", hsl) &&
|
|
parseColorOpacityAndCloseParen(lexer, separatorBeforeAlpha, a)) {
|
|
return [...hslToRGB(hsl), ...a];
|
|
}
|
|
|
|
return null;
|
|
}
|
|
|
|
/**
|
|
* A helper function to parse the color arguments of old style hsl()/hsla()
|
|
* function.
|
|
*
|
|
* @param {CSSLexer} lexer The lexer.
|
|
* @param {Boolean} hasAlpha The color function has alpha component or not.
|
|
* @return {Array} An array of the form [r,g,b,a]; or null on error.
|
|
*/
|
|
function parseOldStyleHsl(lexer, hasAlpha) {
|
|
// hsla() = hsla( <hue>, <saturation>, <lightness>, <alpha-value> )
|
|
// hsl() = hsl( <hue>, <saturation>, <lightness> )
|
|
//
|
|
// <hue> = <number>
|
|
// <alpha-value> = <number>
|
|
|
|
const commaSeparator = ",";
|
|
const closeParen = ")";
|
|
let hsl = [];
|
|
let a = [];
|
|
|
|
// Parse hue.
|
|
let token = getToken(lexer);
|
|
if (!token || token.tokenType !== "number") {
|
|
return null;
|
|
}
|
|
if (!expectSymbol(lexer, commaSeparator)) {
|
|
return null;
|
|
}
|
|
let val = token.number / 360.0;
|
|
hsl.push(val - Math.floor(val));
|
|
|
|
// Parse saturation, lightness and opacity.
|
|
// The saturation and lightness are <percentage>, so reuse the <percentage>
|
|
// version of parseColorComponent function for them. The opacity is <number>
|
|
if (hasAlpha) {
|
|
if (parseColorComponent(lexer, COLOR_COMPONENT_TYPE.percentage,
|
|
commaSeparator, hsl) &&
|
|
parseColorComponent(lexer, COLOR_COMPONENT_TYPE.percentage,
|
|
commaSeparator, hsl) &&
|
|
parseColorComponent(lexer, COLOR_COMPONENT_TYPE.number,
|
|
closeParen, a)) {
|
|
return [...hslToRGB(hsl), ...a];
|
|
}
|
|
} else if (parseColorComponent(lexer, COLOR_COMPONENT_TYPE.percentage,
|
|
commaSeparator, hsl) &&
|
|
parseColorComponent(lexer, COLOR_COMPONENT_TYPE.percentage,
|
|
closeParen, hsl)) {
|
|
return [...hslToRGB(hsl), 1];
|
|
}
|
|
|
|
return null;
|
|
}
|
|
|
|
/**
|
|
* A helper function to parse the color arguments of rgb()/rgba() function.
|
|
* rgb() and rgba() now are aliases.
|
|
*
|
|
* @param {CSSLexer} lexer The lexer.
|
|
* @return {Array} An array of the form [r,g,b,a]; or null on error.
|
|
*/
|
|
function parseRgb(lexer) {
|
|
// comma-less expression:
|
|
// rgb() = rgb( component{3} [ / <alpha-value> ]? )
|
|
// the expression with comma:
|
|
// rgb() = rgb( component#{3} , <alpha-value>? )
|
|
//
|
|
// component = <number> | <percentage>
|
|
// <alpa-value> = <number> | <percentage>
|
|
|
|
const commaSeparator = ",";
|
|
let rgba = [];
|
|
|
|
let token = getToken(lexer);
|
|
if (token.tokenType !== "percentage" && token.tokenType !== "number") {
|
|
return null;
|
|
}
|
|
unGetToken(lexer);
|
|
let type = (token.tokenType === "percentage") ?
|
|
COLOR_COMPONENT_TYPE.percentage :
|
|
COLOR_COMPONENT_TYPE.number;
|
|
|
|
// Parse R.
|
|
if (!parseColorComponent(lexer, type, "", rgba)) {
|
|
return null;
|
|
}
|
|
let hasComma = expectSymbol(lexer, commaSeparator);
|
|
|
|
// Parse G, B and A.
|
|
// No need to check the separator after 'B'. It will be checked in 'A' values
|
|
// parsing.
|
|
let separatorBeforeAlpha = hasComma ? commaSeparator : "/";
|
|
if (parseColorComponent(lexer, type, hasComma ? commaSeparator : "", rgba) &&
|
|
parseColorComponent(lexer, type, "", rgba) &&
|
|
parseColorOpacityAndCloseParen(lexer, separatorBeforeAlpha, rgba)) {
|
|
if (type === COLOR_COMPONENT_TYPE.percentage) {
|
|
rgba[0] = Math.round(255 * rgba[0]);
|
|
rgba[1] = Math.round(255 * rgba[1]);
|
|
rgba[2] = Math.round(255 * rgba[2]);
|
|
}
|
|
return rgba;
|
|
}
|
|
|
|
return null;
|
|
}
|
|
|
|
/**
|
|
* A helper function to parse the color arguments of old style rgb()/rgba()
|
|
* function.
|
|
*
|
|
* @param {CSSLexer} lexer The lexer.
|
|
* @param {Boolean} hasAlpha The color function has alpha component or not.
|
|
* @return {Array} An array of the form [r,g,b,a]; or null on error.
|
|
*/
|
|
function parseOldStyleRgb(lexer, hasAlpha) {
|
|
// rgba() = rgba( component#{3} , <alpha-value> )
|
|
// rgb() = rgb( component#{3} )
|
|
//
|
|
// component = <integer> | <percentage>
|
|
// <alpha-value> = <number>
|
|
|
|
const commaSeparator = ",";
|
|
const closeParen = ")";
|
|
let rgba = [];
|
|
|
|
let token = getToken(lexer);
|
|
if (token.tokenType !== "percentage" &&
|
|
(token.tokenType !== "number" || !token.isInteger)) {
|
|
return null;
|
|
}
|
|
unGetToken(lexer);
|
|
let type = (token.tokenType === "percentage") ?
|
|
COLOR_COMPONENT_TYPE.percentage :
|
|
COLOR_COMPONENT_TYPE.integer;
|
|
|
|
// Parse R. G, B and A.
|
|
if (hasAlpha) {
|
|
if (!parseColorComponent(lexer, type, commaSeparator, rgba) ||
|
|
!parseColorComponent(lexer, type, commaSeparator, rgba) ||
|
|
!parseColorComponent(lexer, type, commaSeparator, rgba) ||
|
|
!parseColorComponent(lexer, COLOR_COMPONENT_TYPE.number,
|
|
closeParen, rgba)) {
|
|
return null;
|
|
}
|
|
} else if (!parseColorComponent(lexer, type, commaSeparator, rgba) ||
|
|
!parseColorComponent(lexer, type, commaSeparator, rgba) ||
|
|
!parseColorComponent(lexer, type, closeParen, rgba)) {
|
|
return null;
|
|
}
|
|
|
|
if (type === COLOR_COMPONENT_TYPE.percentage) {
|
|
rgba[0] = Math.round(255 * rgba[0]);
|
|
rgba[1] = Math.round(255 * rgba[1]);
|
|
rgba[2] = Math.round(255 * rgba[2]);
|
|
}
|
|
if (!hasAlpha) {
|
|
rgba.push(1);
|
|
}
|
|
|
|
return rgba;
|
|
}
|
|
|
|
/**
|
|
* Convert a string representing a color to an object holding the
|
|
* color's components. Any valid CSS color form can be passed in.
|
|
*
|
|
* @param {String} name the color
|
|
* @param {Boolean} useCssColor4ColorFunction use css-color-4 color function or not.
|
|
* @return {Object} an object of the form {r, g, b, a}; or null if the
|
|
* name was not a valid color
|
|
*/
|
|
function colorToRGBA(name, useCssColor4ColorFunction = false) {
|
|
name = name.trim().toLowerCase();
|
|
|
|
if (name in cssColors) {
|
|
let result = cssColors[name];
|
|
return {r: result[0], g: result[1], b: result[2], a: result[3]};
|
|
} else if (name === "transparent") {
|
|
return {r: 0, g: 0, b: 0, a: 0};
|
|
} else if (name === "currentcolor") {
|
|
return {r: 0, g: 0, b: 0, a: 1};
|
|
}
|
|
|
|
let lexer = getCSSLexer(name);
|
|
|
|
let func = getToken(lexer);
|
|
if (!func) {
|
|
return null;
|
|
}
|
|
|
|
if (func.tokenType === "id" || func.tokenType === "hash") {
|
|
if (getToken(lexer) !== null) {
|
|
return null;
|
|
}
|
|
return hexToRGBA(func.text);
|
|
}
|
|
|
|
const expectedFunctions = ["rgba", "rgb", "hsla", "hsl"];
|
|
if (!func || func.tokenType !== "function" ||
|
|
!expectedFunctions.includes(func.text)) {
|
|
return null;
|
|
}
|
|
|
|
let hsl = func.text === "hsl" || func.text === "hsla";
|
|
|
|
let vals;
|
|
if (!useCssColor4ColorFunction) {
|
|
let hasAlpha = (func.text === "rgba" || func.text === "hsla");
|
|
vals = hsl ? parseOldStyleHsl(lexer, hasAlpha) : parseOldStyleRgb(lexer, hasAlpha);
|
|
} else {
|
|
vals = hsl ? parseHsl(lexer) : parseRgb(lexer);
|
|
}
|
|
|
|
if (!vals) {
|
|
return null;
|
|
}
|
|
if (getToken(lexer) !== null) {
|
|
return null;
|
|
}
|
|
|
|
return {r: vals[0], g: vals[1], b: vals[2], a: vals[3]};
|
|
}
|
|
|
|
/**
|
|
* Check whether a string names a valid CSS color.
|
|
*
|
|
* @param {String} name The string to check
|
|
* @param {Boolean} useCssColor4ColorFunction use css-color-4 color function or not.
|
|
* @return {Boolean} True if the string is a CSS color name.
|
|
*/
|
|
function isValidCSSColor(name, useCssColor4ColorFunction = false) {
|
|
return colorToRGBA(name, useCssColor4ColorFunction) !== null;
|
|
}
|