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index.es.mjs
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index.es.mjs
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import parser from 'postcss-value-parser';
import fs from 'fs';
import path from 'path';
import postcss from 'postcss';
import { rgb2hue, hsl2rgb, hwb2rgb, rgb2hsl, hwb2hsl, rgb2hwb, hsl2hwb } from '@csstools/convert-colors';
// return custom selectors from the css root, conditionally removing them
function getCustomProperties(root, opts) {
// initialize custom selectors
const customPropertiesFromHtmlElement = {};
const customPropertiesFromRootPsuedo = {};
// for each html or :root rule
root.nodes.slice().forEach(rule => {
const customPropertiesObject = isHtmlRule(rule)
? customPropertiesFromHtmlElement
: isRootRule(rule)
? customPropertiesFromRootPsuedo
: null;
// for each custom property
if (customPropertiesObject) {
rule.nodes.slice().forEach(decl => {
if (isCustomDecl(decl)) {
const { prop } = decl;
// write the parsed value to the custom property
customPropertiesObject[prop] = parser(decl.value);
// conditionally remove the custom property declaration
if (!opts.preserve) {
decl.remove();
}
}
});
// conditionally remove the empty html or :root rule
if (!opts.preserve && isEmptyParent(rule)) {
rule.remove();
}
}
});
// return all custom properties, preferring :root properties over html properties
return { ...customPropertiesFromHtmlElement, ...customPropertiesFromRootPsuedo };
}
// match html and :root rules
const htmlSelectorRegExp = /^html$/i;
const rootSelectorRegExp = /^:root$/i;
const customPropertyRegExp = /^--[A-z][\w-]*$/;
// whether the node is an html or :root rule
const isHtmlRule = node => node.type === 'rule' && htmlSelectorRegExp.test(node.selector) && Object(node.nodes).length;
const isRootRule = node => node.type === 'rule' && rootSelectorRegExp.test(node.selector) && Object(node.nodes).length;
// whether the node is an custom property
const isCustomDecl = node => node.type === 'decl' && customPropertyRegExp.test(node.prop);
// whether the node is a parent without children
const isEmptyParent = node => Object(node.nodes).length === 0;
/* Import Custom Properties from CSS AST
/* ========================================================================== */
function importCustomPropertiesFromCSSAST(root) {
return getCustomProperties(root, { preserve: true });
}
/* Import Custom Properties from CSS File
/* ========================================================================== */
async function importCustomPropertiesFromCSSFile(from) {
const css = await readFile(from);
const root = postcss.parse(css, { from });
return importCustomPropertiesFromCSSAST(root);
}
/* Import Custom Properties from Object
/* ========================================================================== */
function importCustomPropertiesFromObject(object) {
const customProperties = Object.assign(
{},
Object(object).customProperties || Object(object)['custom-properties']
);
for (const prop in customProperties) {
customProperties[prop] = parser(customProperties[prop]);
}
return customProperties;
}
/* Import Custom Properties from JSON file
/* ========================================================================== */
async function importCustomPropertiesFromJSONFile(from) {
const object = await readJSON(from);
return importCustomPropertiesFromObject(object);
}
/* Import Custom Properties from JS file
/* ========================================================================== */
async function importCustomPropertiesFromJSFile(from) {
const object = await import(from);
return importCustomPropertiesFromObject(('default' in object) ? object.default : object);
}
/* Import Custom Properties from Sources
/* ========================================================================== */
function importCustomPropertiesFromSources(sources) {
return sources.map(source => {
if (source instanceof Promise) {
return source;
} else if (source instanceof Function) {
return source();
}
// read the source as an object
const opts = source === Object(source) ? source : { from: String(source) };
// skip objects with Custom Properties
if (opts.customProperties || opts['custom-properties']) {
return opts
}
// source pathname
const from = path.resolve(String(opts.from || ''));
// type of file being read from
const type = (opts.type || path.extname(from).slice(1)).toLowerCase();
return { type, from };
}).reduce(async (customProperties, source) => {
const { type, from } = await source;
if (type === 'ast') {
return Object.assign(await customProperties, importCustomPropertiesFromCSSAST(from));
}
if (type === 'css') {
return Object.assign(await customProperties, await importCustomPropertiesFromCSSFile(from));
}
if (type === 'js') {
return Object.assign(await customProperties, await importCustomPropertiesFromJSFile(from));
}
if (type === 'json') {
return Object.assign(await customProperties, await importCustomPropertiesFromJSONFile(from));
}
return Object.assign(await customProperties, await importCustomPropertiesFromObject(await source));
}, {});
}
/* Helper utilities
/* ========================================================================== */
const readFile = from => new Promise((resolve, reject) => {
fs.readFile(from, 'utf8', (error, result) => {
if (error) {
reject(error);
} else {
resolve(result);
}
});
});
const readJSON = async from => JSON.parse(await readFile(from));
/* Convert Degree to Hue Degree
/* ========================================================================== */
function convertDtoD(deg) {
return deg % 360;
}
/* Convert Gradian to Hue Degree
/* ========================================================================== */
function convertGtoD(grad) {
return grad * 0.9 % 360;
}
/* Convert Radian to Hue Degree
/* ========================================================================== */
function convertRtoD(rad) {
return rad * 180 / Math.PI % 360;
}
/* Convert Turn to Hue Degree
/* ========================================================================== */
function convertTtoD(turn) {
return turn * 360 % 360;
}
/* Convert a Name to Red/Green/Blue
/* ========================================================================== */
function convertNtoRGB(name) {
const names = {
aliceblue: [240, 248, 255],
antiquewhite: [250, 235, 215],
aqua: [0, 255, 255],
aquamarine: [127, 255, 212],
azure: [240, 255, 255],
beige: [245, 245, 220],
bisque: [255, 228, 196],
black: [0, 0, 0],
blanchedalmond: [255, 235, 205],
blue: [0, 0, 255],
blueviolet: [138, 43, 226],
brown: [165, 42, 42],
burlywood: [222, 184, 135],
cadetblue: [95, 158, 160],
chartreuse: [127, 255, 0],
chocolate: [210, 105, 30],
coral: [255, 127, 80],
cornflowerblue: [100, 149, 237],
cornsilk: [255, 248, 220],
crimson: [220, 20, 60],
cyan: [0, 255, 255],
darkblue: [0, 0, 139],
darkcyan: [0, 139, 139],
darkgoldenrod: [184, 134, 11],
darkgray: [169, 169, 169],
darkgreen: [0, 100, 0],
darkgrey: [169, 169, 169],
darkkhaki: [189, 183, 107],
darkmagenta: [139, 0, 139],
darkolivegreen: [85, 107, 47],
darkorange: [255, 140, 0],
darkorchid: [153, 50, 204],
darkred: [139, 0, 0],
darksalmon: [233, 150, 122],
darkseagreen: [143, 188, 143],
darkslateblue: [72, 61, 139],
darkslategray: [47, 79, 79],
darkslategrey: [47, 79, 79],
darkturquoise: [0, 206, 209],
darkviolet: [148, 0, 211],
deeppink: [255, 20, 147],
deepskyblue: [0, 191, 255],
dimgray: [105, 105, 105],
dimgrey: [105, 105, 105],
dodgerblue: [30, 144, 255],
firebrick: [178, 34, 34],
floralwhite: [255, 250, 240],
forestgreen: [34, 139, 34],
fuchsia: [255, 0, 255],
gainsboro: [220, 220, 220],
ghostwhite: [248, 248, 255],
gold: [255, 215, 0],
goldenrod: [218, 165, 32],
gray: [128, 128, 128],
green: [0, 128, 0],
greenyellow: [173, 255, 47],
grey: [128, 128, 128],
honeydew: [240, 255, 240],
hotpink: [255, 105, 180],
indianred: [205, 92, 92],
indigo: [75, 0, 130],
ivory: [255, 255, 240],
khaki: [240, 230, 140],
lavender: [230, 230, 250],
lavenderblush: [255, 240, 245],
lawngreen: [124, 252, 0],
lemonchiffon: [255, 250, 205],
lightblue: [173, 216, 230],
lightcoral: [240, 128, 128],
lightcyan: [224, 255, 255],
lightgoldenrodyellow: [250, 250, 210],
lightgray: [211, 211, 211],
lightgreen: [144, 238, 144],
lightgrey: [211, 211, 211],
lightpink: [255, 182, 193],
lightsalmon: [255, 160, 122],
lightseagreen: [32, 178, 170],
lightskyblue: [135, 206, 250],
lightslategray: [119, 136, 153],
lightslategrey: [119, 136, 153],
lightsteelblue: [176, 196, 222],
lightyellow: [255, 255, 224],
lime: [0, 255, 0],
limegreen: [50, 205, 50],
linen: [250, 240, 230],
magenta: [255, 0, 255],
maroon: [128, 0, 0],
mediumaquamarine: [102, 205, 170],
mediumblue: [0, 0, 205],
mediumorchid: [186, 85, 211],
mediumpurple: [147, 112, 219],
mediumseagreen: [60, 179, 113],
mediumslateblue: [123, 104, 238],
mediumspringgreen: [0, 250, 154],
mediumturquoise: [72, 209, 204],
mediumvioletred: [199, 21, 133],
midnightblue: [25, 25, 112],
mintcream: [245, 255, 250],
mistyrose: [255, 228, 225],
moccasin: [255, 228, 181],
navajowhite: [255, 222, 173],
navy: [0, 0, 128],
oldlace: [253, 245, 230],
olive: [128, 128, 0],
olivedrab: [107, 142, 35],
orange: [255, 165, 0],
orangered: [255, 69, 0],
orchid: [218, 112, 214],
palegoldenrod: [238, 232, 170],
palegreen: [152, 251, 152],
paleturquoise: [175, 238, 238],
palevioletred: [219, 112, 147],
papayawhip: [255, 239, 213],
peachpuff: [255, 218, 185],
peru: [205, 133, 63],
pink: [255, 192, 203],
plum: [221, 160, 221],
powderblue: [176, 224, 230],
purple: [128, 0, 128],
rebeccapurple: [102, 51, 153],
red: [255, 0, 0],
rosybrown: [188, 143, 143],
royalblue: [65, 105, 225],
saddlebrown: [139, 69, 19],
salmon: [250, 128, 114],
sandybrown: [244, 164, 96],
seagreen: [46, 139, 87],
seashell: [255, 245, 238],
sienna: [160, 82, 45],
silver: [192, 192, 192],
skyblue: [135, 206, 235],
slateblue: [106, 90, 205],
slategray: [112, 128, 144],
slategrey: [112, 128, 144],
snow: [255, 250, 250],
springgreen: [0, 255, 127],
steelblue: [70, 130, 180],
tan: [210, 180, 140],
teal: [0, 128, 128],
thistle: [216, 191, 216],
tomato: [255, 99, 71],
transparent: [0, 0, 0],
turquoise: [64, 224, 208],
violet: [238, 130, 238],
wheat: [245, 222, 179],
white: [255, 255, 255],
whitesmoke: [245, 245, 245],
yellow: [255, 255, 0],
yellowgreen: [154, 205, 50]
};
return names[name] && names[name].map(c => c / 2.55);
}
/* Convert a Hex to Red/Green/Blue
/* ========================================================================== */
function convertHtoRGB(hex) {
// #<hex-color>{3,4,6,8}
const [r, g, b, a, rr, gg, bb, aa] = (hex.match(hexColorMatch$1) || []).slice(1);
if (rr !== undefined || r !== undefined) {
const red = rr !== undefined ? parseInt(rr, 16) : r !== undefined ? parseInt(r + r, 16) : 0;
const green = gg !== undefined ? parseInt(gg, 16) : g !== undefined ? parseInt(g + g, 16) : 0;
const blue = bb !== undefined ? parseInt(bb, 16) : b !== undefined ? parseInt(b + b, 16) : 0;
const alpha = aa !== undefined ? parseInt(aa, 16) : a !== undefined ? parseInt(a + a, 16) : 255;
return [red, green, blue, alpha].map(c => c / 2.55);
}
return undefined;
}
const hexColorMatch$1 = /^#(?:([a-f0-9])([a-f0-9])([a-f0-9])([a-f0-9])?|([a-f0-9]{2})([a-f0-9]{2})([a-f0-9]{2})([a-f0-9]{2})?)$/i;
class Color {
constructor(color) {
this.color = Object(Object(color).color || color);
this.color.colorspace = this.color.colorspace
? this.color.colorspace
: 'red' in color && 'green' in color && 'blue' in color
? 'rgb'
: 'hue' in color && 'saturation' in color && 'lightness' in color
? 'hsl'
: 'hue' in color && 'whiteness' in color && 'blackness' in color
? 'hwb'
: 'unknown';
if (color.colorspace === 'rgb') {
this.color.hue = rgb2hue(color.red, color.green, color.blue, color.hue || 0);
}
}
alpha(alpha) {
const color = this.color;
return alpha === undefined
? color.alpha
: new Color(assign(color, { alpha }));
}
blackness(blackness) {
const hwb = color2hwb(this.color);
return blackness === undefined
? hwb.blackness
: new Color(assign(hwb, { blackness }));
}
blend(color, percentage, colorspace = 'rgb') {
const base = this.color;
return new Color(blend(base, color, percentage, colorspace));
}
blenda(color, percentage, colorspace = 'rgb') {
const base = this.color;
return new Color(blend(base, color, percentage, colorspace, true));
}
blue(blue) {
const rgb = color2rgb(this.color);
return blue === undefined
? rgb.blue
: new Color(assign(rgb, { blue }));
}
contrast(percentage) {
const base = this.color;
return new Color(contrast(base, percentage));
}
green(green) {
const rgb = color2rgb(this.color);
return green === undefined
? rgb.green
: new Color(assign(rgb, { green }));
}
hue(hue) {
const hsl = color2hsl(this.color);
return hue === undefined
? hsl.hue
: new Color(assign(hsl, { hue }));
}
lightness(lightness) {
const hsl = color2hsl(this.color);
return lightness === undefined
? hsl.lightness
: new Color(assign(hsl, { lightness }))
}
red(red) {
const rgb = color2rgb(this.color);
return red === undefined
? rgb.red
: new Color(assign(rgb, { red }));
}
rgb(red, green, blue) {
const rgb = color2rgb(this.color);
return new Color(assign(rgb, { red, green, blue }));
}
saturation(saturation) {
const hsl = color2hsl(this.color);
return saturation === undefined
? hsl.saturation
: new Color(assign(hsl, { saturation }));
}
shade(percentage) {
const hwb = color2hwb(this.color);
const shade = { hue: 0, whiteness: 0, blackness: 100, colorspace: 'hwb' };
const colorspace = 'rgb';
return percentage === undefined
? hwb.blackness
: new Color(blend(hwb, shade, percentage, colorspace));
}
tint(percentage) {
const hwb = color2hwb(this.color);
const tint = { hue: 0, whiteness: 100, blackness: 0, colorspace: 'hwb' };
const colorspace = 'rgb';
return percentage === undefined
? hwb.blackness
: new Color(blend(hwb, tint, percentage, colorspace));
}
whiteness(whiteness) {
const hwb = color2hwb(this.color);
return whiteness === undefined
? hwb.whiteness
: new Color(assign(hwb, { whiteness }));
}
toHSL() {
return color2hslString(this.color);
}
toHWB() {
return color2hwbString(this.color);
}
toLegacy() {
return color2legacyString(this.color);
}
toRGB() {
return color2rgbString(this.color);
}
toRGBLegacy() {
return color2rgbLegacyString(this.color);
}
toString() {
return color2string(this.color);
}
}
/* Blending
/* ========================================================================== */
function blend(base, color, percentage, colorspace, isBlendingAlpha) {
const addition = percentage / 100;
const subtraction = 1 - addition;
if (colorspace === 'hsl') {
const { hue: h1, saturation: s1, lightness: l1, alpha: a1 } = color2hsl(base);
const { hue: h2, saturation: s2, lightness: l2, alpha: a2 } = color2hsl(color);
const [hue, saturation, lightness, alpha] = [
h1 * subtraction + h2 * addition,
s1 * subtraction + s2 * addition,
l1 * subtraction + l2 * addition,
isBlendingAlpha
? a1 * subtraction + a2 * addition
: a1
];
return { hue, saturation, lightness, alpha, colorspace: 'hsl' };
} else if (colorspace === 'hwb') {
const { hue: h1, whiteness: w1, blackness: b1, alpha: a1 } = color2hwb(base);
const { hue: h2, whiteness: w2, blackness: b2, alpha: a2 } = color2hwb(color);
const [hue, whiteness, blackness, alpha] = [
h1 * subtraction + h2 * addition,
w1 * subtraction + w2 * addition,
b1 * subtraction + b2 * addition,
isBlendingAlpha
? a1 * subtraction + a2 * addition
: a1
];
return { hue, whiteness, blackness, alpha, colorspace: 'hwb' };
} else {
const { red: r1, green: g1, blue: b1, alpha: a1 } = color2rgb(base);
const { red: r2, green: g2, blue: b2, alpha: a2 } = color2rgb(color);
const [red, green, blue, alpha] = [
r1 * subtraction + r2 * addition,
g1 * subtraction + g2 * addition,
b1 * subtraction + b2 * addition,
isBlendingAlpha
? a1 * subtraction + a2 * addition
: a1
];
return { red, green, blue, alpha, colorspace: 'rgb' };
}
}
/* Assign channels to a new instance of a base color
/* ========================================================================== */
function assign(base, channels) {
const color = Object.assign({}, base);
Object.keys(channels).forEach(
channel => {
// detect channel
const channelIsHue = channel === 'hue';
const isRGB = !channelIsHue && blueGreenRedMatch.test(channel);
// normalized value of the channel
const value = normalize(channels[channel], channel);
// assign channel to new object
color[channel] = value;
if (isRGB) {
// conditionally preserve the hue
color.hue = rgb2hue(color.red, color.green, color.blue, base.hue || 0);
}
}
);
return color;
}
function normalize(value, channel) {
// detect channel
const channelIsHue = channel === 'hue';
// value limitations
const min = 0;
const max = channelIsHue ? 360 : 100;
const normalizedValue = Math.min(Math.max(channelIsHue
? value % 360
: value, min), max);
return normalizedValue;
}
/* Convert colors
/* ========================================================================== */
function color2rgb(color) {
const [ red, green, blue ] = color.colorspace === 'hsl'
? hsl2rgb(color.hue, color.saturation, color.lightness)
: color.colorspace === 'hwb'
? hwb2rgb(color.hue, color.whiteness, color.blackness)
: [ color.red, color.green, color.blue ];
return { red, green, blue, hue: color.hue, alpha: color.alpha, colorspace: 'rgb' };
}
function color2hsl(color) {
const [ hue, saturation, lightness ] = color.colorspace === 'rgb'
? rgb2hsl(color.red, color.green, color.blue, color.hue)
: color.colorspace === 'hwb'
? hwb2hsl(color.hue, color.whiteness, color.blackness)
: [ color.hue, color.saturation, color.lightness ];
return { hue, saturation, lightness, alpha: color.alpha, colorspace: 'hsl' };
}
function color2hwb(color) {
const [ hue, whiteness, blackness ] = color.colorspace === 'rgb'
? rgb2hwb(color.red, color.green, color.blue, color.hue)
: color.colorspace === 'hsl'
? hsl2hwb(color.hue, color.saturation, color.lightness)
: [ color.hue, color.whiteness, color.blackness ];
return { hue, whiteness, blackness, alpha: color.alpha, colorspace: 'hwb' };
}
/* Contrast functions
/* ========================================================================== */
function contrast(color, percentage) {
// https://drafts.csswg.org/css-color/#contrast-adjuster
const hwb = color2hwb(color);
const rgb = color2rgb(color);
// compute the luminance of the color.
const luminance = rgb2luminance(rgb.red, rgb.green, rgb.blue);
// the maximum-contrast color, if it is less than .5
const maxContrastColor = luminance < 0.5
// hwb(X, 100%, 0%), where X is the hue angle of the color
? { hue: hwb.hue, whiteness: 100, blackness: 0, alpha: hwb.alpha, colorspace: 'hwb' }
// otherwise, hwb(X, 0%, 100%), where X is the hue angle of the color
: { hue: hwb.hue, whiteness: 0, blackness: 100, alpha: hwb.alpha, colorspace: 'hwb' };
// contrast ratio
const contrastRatio = colors2contrast(color, maxContrastColor);
const minContrastColor = contrastRatio > 4.5
// the color with the smallest contrast ratio with the base color that is greater than 4.5
? colors2contrastRatioColor(hwb, maxContrastColor)
// otherwise, the maximum-contrast color
: maxContrastColor;
// color(maximum-contrast blend(minimum-contrast <percentage> hwb)));
return blend(maxContrastColor, minContrastColor, percentage, 'hwb', false);
}
function colors2contrast(color1, color2) {
// https://drafts.csswg.org/css-color/#contrast-ratio
const rgb1 = color2rgb(color1);
const rgb2 = color2rgb(color2);
const l1 = rgb2luminance(rgb1.red, rgb1.green, rgb1.blue);
const l2 = rgb2luminance(rgb2.red, rgb2.green, rgb2.blue);
return l1 > l2
// if l1 is the relative luminance of the lighter of the colors
? (l1 + 0.05) / (l2 + 0.05)
// otherwise, if l2 is the relative luminance of the lighter of the colors
: (l2 + 0.05) / (l1 + 0.05);
}
function rgb2luminance(red, green, blue) {
const [ redLuminance, greenLuminance, blueLuminance ] = [
channel2luminance(red),
channel2luminance(green),
channel2luminance(blue)
];
// https://drafts.csswg.org/css-color/#luminance
const luminance = 0.2126 * redLuminance + 0.7152 * greenLuminance + 0.0722 * blueLuminance;
return luminance;
}
function channel2luminance(value) {
// https://drafts.csswg.org/css-color/#luminance
const luminance = value <= 0.03928 ? value / 12.92 : Math.pow((value + 0.055) /1.055, 2.4);
return luminance;
}
// return the smallest contrast ratio from a color and a maximum contrast (credit: @thetalecrafter)
function colors2contrastRatioColor(hwb, maxHWB) {
const modifiedHWB = Object.assign({}, hwb);
// values to be used for linear interpolations in HWB space
let minW = hwb.whiteness;
let minB = hwb.blackness;
let maxW = maxHWB.whiteness;
let maxB = maxHWB.blackness;
// find the color with the smallest contrast ratio with the base color that is greater than 4.5
while (Math.abs(minW - maxW) > 100 || Math.abs(minB - maxB) > 100) {
const midW = Math.round((maxW + minW) / 2);
const midB = Math.round((maxB + minB) / 2);
modifiedHWB.whiteness = midW;
modifiedHWB.blackness = midB;
if (colors2contrast(modifiedHWB, hwb) > 4.5) {
maxW = midW;
maxB = midB;
} else {
minW = midW;
minB = midB;
}
}
return modifiedHWB;
}
/* Match
/* ========================================================================== */
const blueGreenRedMatch = /^(blue|green|red)$/i;
/* Stringifiers
/* ========================================================================== */
function color2string(color) {
return color.colorspace === 'hsl'
? color2hslString(color)
: color.colorspace === 'hwb'
? color2hwbString(color)
: color2rgbString(color);
}
function color2hslString(color) {
const hsl = color2hsl(color);
const isOpaque = hsl.alpha === 100;
const hue = hsl.hue;
const saturation = Math.round(hsl.saturation * 10000000000) / 10000000000;
const lightness = Math.round(hsl.lightness * 10000000000) / 10000000000;
const alpha = Math.round(hsl.alpha * 10000000000) / 10000000000;
return `hsl(${hue} ${saturation}% ${lightness}%${isOpaque
? ''
: ` / ${alpha}%`})`;
}
function color2hwbString(color) {
const hwb = color2hwb(color);
const isOpaque = hwb.alpha === 100;
const hue = hwb.hue;
const whiteness = Math.round(hwb.whiteness * 10000000000) / 10000000000;
const blackness = Math.round(hwb.blackness * 10000000000) / 10000000000;
const alpha = Math.round(hwb.alpha * 10000000000) / 10000000000;
return `hwb(${hue} ${whiteness}% ${blackness}%${isOpaque
? ''
: ` / ${alpha}%`})`;
}
function color2rgbString(color) {
const rgb = color2rgb(color);
const isOpaque = rgb.alpha === 100;
const red = Math.round(rgb.red * 10000000000) / 10000000000;
const green = Math.round(rgb.green * 10000000000) / 10000000000;
const blue = Math.round(rgb.blue * 10000000000) / 10000000000;
const alpha = Math.round(rgb.alpha * 10000000000) / 10000000000;
return `rgb(${red}% ${green}% ${blue}%${isOpaque
? ''
: ` / ${alpha}%`})`;
}
function color2legacyString(color) {
return color.colorspace === 'hsl'
? color2hslLegacyString(color)
: color2rgbLegacyString(color);
}
function color2rgbLegacyString(color) {
const rgb = color2rgb(color);
const isOpaque = rgb.alpha === 100;
const name = isOpaque ? 'rgb' : 'rgba';
const red = Math.round(rgb.red * 255 / 100);
const green = Math.round(rgb.green * 255 / 100);
const blue = Math.round(rgb.blue * 255 / 100);
const alpha = Math.round(rgb.alpha / 100 * 10000000000) / 10000000000;
return `${name}(${red}, ${green}, ${blue}${isOpaque
? ''
: `, ${alpha}`})`;
}
function color2hslLegacyString(color) {
const hsl = color2hsl(color);
const isOpaque = hsl.alpha === 100;
const name = isOpaque ? 'hsl' : 'hsla';
const hue = hsl.hue;
const saturation = Math.round(hsl.saturation * 10000000000) / 10000000000;
const lightness = Math.round(hsl.lightness * 10000000000) / 10000000000;
const alpha = Math.round(hsl.alpha / 100 * 10000000000) / 10000000000;
return `${name}(${hue}, ${saturation}%, ${lightness}%${isOpaque
? ''
: `, ${alpha}`})`;
}
function manageUnresolved(node, opts, word, message) {
if ('warn' === opts.unresolved) {
opts.decl.warn(opts.result, message, { word });
} else if ('ignore' !== opts.unresolved) {
throw opts.decl.error(message, { word });
}
}
// tooling
/* Transform AST
/* ========================================================================== */
function transformAST(node, opts) {
node.nodes.slice(0).forEach((child, index) => {
if (isColorModFunction(child)) {
// transform any variables within the color-mod() function
if (opts.transformVars) {
transformVariables(child, opts);
}
// transform any color-mod() functions
const color = transformColorModFunction(child, opts);
if (color) {
// update the color-mod() function with the transformed value
node.nodes.splice(index, 1, {
type: 'word',
value: opts.stringifier(color)
});
}
} else if (child.nodes && Object(child.nodes).length) {
transformAST(child, opts);
}
});
}
/* Transform <var> functions
/* ========================================================================== */
function transformVariables(node, opts) {
parser.walk(node.nodes, (child, index, nodes) => {
if (isVariable(child)) {
// get the custom property and fallback value from var()
const [prop, fallbackNode] = transformArgsByParams(child, [
// <value> , [ <fallback> ]?
[transformWord, isComma, transformNode]
]);
// if the custom property is known
if (prop in opts.customProperties) {
let customPropertyValue = opts.customProperties[prop];
// follow custom properties referencing custom properties
if (looseVarMatch.test(parser.stringify(customPropertyValue))) {
const rootChildAST = JSON.parse(JSON.stringify({ nodes: customPropertyValue.nodes }));
transformVariables(rootChildAST, opts);
customPropertyValue = rootChildAST;
}
// replace var() with the custom property value
if (customPropertyValue.nodes.length) {
nodes.splice(index, 0, ...JSON.parse(JSON.stringify(customPropertyValue.nodes)));
}
nodes.splice(nodes.indexOf(child), 1);
} else if (fallbackNode && fallbackNode.nodes.length === 1 && fallbackNode.nodes[0].nodes.length) {
// otherwise, replace var() with the fallback value
transformVariables(fallbackNode, opts);
nodes.splice(index, 1, ...fallbackNode.nodes[0].nodes[0]);
}
}
});
}
/* Transform <color> functions
/* ========================================================================== */
function transformColor(node, opts) {
if (isRGBFunction(node)) {
return transformRGBFunction(node, opts);
} else if (isHSLFunction(node)) {
return transformHSLFunction(node, opts);
} else if (isHWBFunction(node)) {
return transformHWBFunction(node, opts);
} else if (isColorModFunction(node)) {
return transformColorModFunction(node, opts);
} else if (isHexColor(node)) {
return transformHexColor(node, opts);
} else if (isNamedColor(node)) {
return transformNamedColor(node, opts);
} else {
return manageUnresolved(node, opts, node.value, `Expected a color`);
}
}
// return a transformed rgb/rgba color function
function transformRGBFunction(node, opts) {
const [red, green, blue, alpha = 100] = transformArgsByParams(node, [
// <percentage> <percentage> <percentage> [ , <alpha-value> ]?
[transformPercentage, transformPercentage, transformPercentage, isSlash, transformAlpha],
// <number> <number> <number> [ , <alpha-value> ]?
[transformRGBNumber, transformRGBNumber, transformRGBNumber, isSlash, transformAlpha],
// <percentage> , <percentage> , <percentage> [ , <alpha-value> ]?
[transformPercentage, isComma, transformPercentage, isComma, transformPercentage, isComma, transformAlpha],
// <number> , <number> , <number> [ , <alpha-value> ]?
[transformRGBNumber, isComma, transformRGBNumber, isComma, transformRGBNumber, isComma, transformAlpha]
]);
if (red !== undefined) {
const color = new Color({ red, green, blue, alpha, colorspace: 'rgb' });
return color;
} else {
return manageUnresolved(node, opts, node.value, `Expected a valid rgb() function`);
}
}
// return a transformed hsl/hsla color function
function transformHSLFunction(node, opts) {
const [hue, saturation, lightness, alpha = 100] = transformArgsByParams(node, [
// <hue> <percentage> <percentage> [ / <alpha-value> ]?
[transformHue, transformPercentage, transformPercentage, isSlash, transformAlpha],
// <hue> , <percentage> , <percentage> [ , <alpha-value> ]?
[transformHue, isComma, transformPercentage, isComma, transformPercentage, isComma, transformAlpha]
]);
if (lightness !== undefined) {
const color = new Color({ hue, saturation, lightness, alpha, colorspace: 'hsl' });
return color;
} else {
return manageUnresolved(node, opts, node.value, `Expected a valid hsl() function`);
}
}
// return a transformed hwb color function
function transformHWBFunction(node, opts) {
const [hue, whiteness, blackness, alpha = 100] = transformArgsByParams(node, [