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Copy pathparser.ts
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772 lines (690 loc) · 20.9 KB
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import { Color } from '../color';
import { getKnownColor } from '../color/known-colors';
export type Parsed<V> = { start: number; end: number; value: V };
// Values
export type URL = string;
export type Angle = number;
export interface Unit<T> {
value: number;
unit: string;
}
export type Length = Unit<'px' | 'dip'>;
export type Percentage = Unit<'%'>;
export type LengthPercentage = Length | Percentage;
export type Keyword = string;
export interface ColorStop {
color: Color;
offset?: LengthPercentage;
}
export interface LinearGradient {
angle: number;
colors: ColorStop[];
}
export interface Background {
readonly color?: number | Color;
readonly image?: URL | LinearGradient;
readonly repeat?: BackgroundRepeat;
readonly position?: BackgroundPosition;
readonly size?: BackgroundSize;
}
export type BackgroundRepeat = 'repeat' | 'repeat-x' | 'repeat-y' | 'no-repeat';
export type BackgroundSize =
| 'auto'
| 'cover'
| 'contain'
| {
x: LengthPercentage;
y: 'auto' | LengthPercentage;
};
export type HorizontalAlign = 'left' | 'center' | 'right';
export type VerticalAlign = 'top' | 'center' | 'bottom';
export interface HorizontalAlignWithOffset {
readonly align: 'left' | 'right';
readonly offset: LengthPercentage;
}
export interface VerticalAlignWithOffset {
readonly align: 'top' | 'bottom';
readonly offset: LengthPercentage;
}
export interface BackgroundPosition {
readonly x: HorizontalAlign | HorizontalAlignWithOffset;
readonly y: VerticalAlign | VerticalAlignWithOffset;
text?: string;
}
const urlRegEx = /\s*url\((?:(['"])([^\1]*)\1|([^)]*))\)\s*/gy;
export function parseURL(text: string, start = 0): Parsed<URL> {
urlRegEx.lastIndex = start;
const result = urlRegEx.exec(text);
if (!result) {
return null;
}
const end = urlRegEx.lastIndex;
const value: URL = result[2] || result[3];
return { start, end, value };
}
const hexColorRegEx = /\s*#((?:[0-9A-F]{8})|(?:[0-9A-F]{6})|(?:[0-9A-F]{4})|(?:[0-9A-F]{3}))\s*/giy;
export function parseHexColor(text: string, start = 0): Parsed<Color> {
hexColorRegEx.lastIndex = start;
const result = hexColorRegEx.exec(text);
if (!result) {
return null;
}
const end = hexColorRegEx.lastIndex;
return { start, end, value: new Color('#' + result[1]) };
}
const cssColorRegEx = /\s*((?:rgb|rgba|hsl|hsla|hsv|hsva)\([^\(\)]*\))/gy;
export function parseCssColor(text: string, start = 0): Parsed<Color> {
cssColorRegEx.lastIndex = start;
const result = cssColorRegEx.exec(text);
if (!result) {
return null;
}
const end = cssColorRegEx.lastIndex;
try {
return { start, end, value: new Color(result[1]) };
} catch {
return null;
}
}
export function convertHSLToRGBColor(hue: number, saturation: number, lightness: number): { r: number; g: number; b: number } {
// Per formula it will be easier if hue is divided to 60° and saturation to 100 beforehand
// https://en.wikipedia.org/wiki/HSL_and_HSV#HSL_to_RGB
hue /= 60;
lightness /= 100;
const chroma = ((1 - Math.abs(2 * lightness - 1)) * saturation) / 100,
X = chroma * (1 - Math.abs((hue % 2) - 1));
// Add lightness match to all RGB components beforehand
let { m: r, m: g, m: b } = { m: lightness - chroma / 2 };
if (0 <= hue && hue < 1) {
r += chroma;
g += X;
} else if (hue < 2) {
r += X;
g += chroma;
} else if (hue < 3) {
g += chroma;
b += X;
} else if (hue < 4) {
g += X;
b += chroma;
} else if (hue < 5) {
r += X;
b += chroma;
} else if (hue < 6) {
r += chroma;
b += X;
}
return {
r: Math.round(r * 0xff),
g: Math.round(g * 0xff),
b: Math.round(b * 0xff),
};
}
export function parseColorKeyword(value, start: number, keyword = parseKeyword(value, start)): Parsed<Color> {
const parseColor = keyword && getKnownColor(keyword.value);
if (parseColor != null) {
const end = keyword.end;
return { start, end, value: new Color(parseColor) };
}
return null;
}
export function parseColor(value: string, start = 0, keyword = parseKeyword(value, start)): Parsed<Color> {
return parseHexColor(value, start) || parseColorKeyword(value, start, keyword) || parseCssColor(value, start);
}
const keywordRegEx = /\s*([a-z][\w\-]*)\s*/giy;
function parseKeyword(text: string, start = 0): Parsed<Keyword> {
keywordRegEx.lastIndex = start;
const result = keywordRegEx.exec(text);
if (!result) {
return null;
}
const end = keywordRegEx.lastIndex;
const value = result[1];
return { start, end, value };
}
const backgroundRepeatKeywords = new Set(['repeat', 'repeat-x', 'repeat-y', 'no-repeat']);
export function parseRepeat(value: string, start = 0, keyword = parseKeyword(value, start)): Parsed<BackgroundRepeat> {
if (keyword && backgroundRepeatKeywords.has(keyword.value)) {
const end = keyword.end;
const value = <BackgroundRepeat>keyword.value;
return { start, end, value };
}
return null;
}
const unitRegEx = /\s*([+\-]?(?:\d+\.\d+|\d+|\.\d+)(?:[eE][+\-]?\d+)?)([a-zA-Z]+|%)?\s*/gy;
export function parseUnit(text: string, start = 0): Parsed<Unit<string>> {
unitRegEx.lastIndex = start;
const result = unitRegEx.exec(text);
if (!result) {
return null;
}
const end = unitRegEx.lastIndex;
const value = parseFloat(result[1]);
const unit = <any>result[2] || 'dip';
return { start, end, value: { value, unit } };
}
export function parsePercentageOrLength(text: string, start = 0): Parsed<LengthPercentage> {
const unitResult = parseUnit(text, start);
if (unitResult) {
const { start, end } = unitResult;
const value = <LengthPercentage>unitResult.value;
if (value.unit === '%') {
value.value /= 100;
} else if (!value.unit) {
value.unit = 'dip';
} else if (value.unit === 'px' || value.unit === 'dip') {
// same
} else {
return null;
}
return { start, end, value };
}
return null;
}
const angleUnitsToRadMap: {
[unit: string]: (start: number, end: number, value: number) => Parsed<Angle>;
} = {
deg: (start: number, end: number, deg: number) => ({
start,
end,
value: (deg / 180) * Math.PI,
}),
rad: (start: number, end: number, rad: number) => ({
start,
end,
value: rad,
}),
grad: (start: number, end: number, grad: number) => ({
start,
end,
value: (grad / 200) * Math.PI,
}),
turn: (start: number, end: number, turn: number) => ({
start,
end,
value: turn * Math.PI * 2,
}),
};
export function parseAngle(value: string, start = 0): Parsed<Angle> {
const angleResult = parseUnit(value, start);
if (angleResult) {
const { start, end, value } = angleResult;
return (angleUnitsToRadMap[value.unit] || ((_, __, ___) => null))(start, end, value.value);
}
return null;
}
const backgroundSizeKeywords = new Set(['auto', 'contain', 'cover']);
export function parseBackgroundSize(value: string, start = 0, keyword = parseKeyword(value, start)): Parsed<BackgroundSize> {
let end = start;
if (keyword && backgroundSizeKeywords.has(keyword.value)) {
end = keyword.end;
const value = <'auto' | 'cover' | 'contain'>keyword.value;
return { start, end, value };
}
// Parse one or two lengths... the other will be "auto"
const firstLength = parsePercentageOrLength(value, end);
if (firstLength) {
end = firstLength.end;
const secondLength = parsePercentageOrLength(value, firstLength.end);
if (secondLength) {
end = secondLength.end;
return {
start,
end,
value: { x: firstLength.value, y: secondLength.value },
};
} else {
return { start, end, value: { x: firstLength.value, y: 'auto' } };
}
}
return null;
}
const backgroundPositionKeywords = Object.freeze(new Set(['left', 'right', 'top', 'bottom', 'center']));
const backgroundPositionKeywordsDirection: {
[align: string]: 'x' | 'center' | 'y';
} = {
left: 'x',
right: 'x',
center: 'center',
top: 'y',
bottom: 'y',
};
export function parseBackgroundPosition(text: string, start = 0, keyword = parseKeyword(text, start)): Parsed<BackgroundPosition> {
function formatH(align: Parsed<HorizontalAlign>, offset: Parsed<LengthPercentage>) {
if (align.value === 'center') {
return 'center';
}
if (offset && offset.value.value !== 0) {
return { align: align.value, offset: offset.value };
}
return align.value;
}
function formatV(align: Parsed<VerticalAlign>, offset: Parsed<LengthPercentage>) {
if (align.value === 'center') {
return 'center';
}
if (offset && offset.value.value !== 0) {
return { align: align.value, offset: offset.value };
}
return align.value;
}
let end = start;
if (keyword && backgroundPositionKeywords.has(keyword.value)) {
end = keyword.end;
const firstDirection = backgroundPositionKeywordsDirection[keyword.value];
const firstLength = firstDirection !== 'center' && parsePercentageOrLength(text, end);
if (firstLength) {
end = firstLength.end;
}
const secondKeyword = parseKeyword(text, end);
if (secondKeyword && backgroundPositionKeywords.has(secondKeyword.value)) {
end = secondKeyword.end;
const secondDirection = backgroundPositionKeywordsDirection[secondKeyword.end];
if (firstDirection === secondDirection && firstDirection !== 'center') {
return null; // Reject pair of both horizontal or both vertical alignments.
}
const secondLength = secondDirection !== 'center' && parsePercentageOrLength(text, end);
if (secondLength) {
end = secondLength.end;
}
if ((firstDirection === secondDirection && secondDirection === 'center') || firstDirection === 'x' || secondDirection === 'y') {
return {
start,
end,
value: {
x: formatH(<Parsed<HorizontalAlign>>keyword, firstLength),
y: formatV(<Parsed<VerticalAlign>>secondKeyword, secondLength),
},
};
} else {
return {
start,
end,
value: {
x: formatH(<Parsed<HorizontalAlign>>secondKeyword, secondLength),
y: formatV(<Parsed<VerticalAlign>>keyword, firstLength),
},
};
}
} else {
if (firstDirection === 'center') {
return { start, end, value: { x: 'center', y: 'center' } };
} else if (firstDirection === 'x') {
return {
start,
end,
value: {
x: formatH(<Parsed<HorizontalAlign>>keyword, firstLength),
y: 'center',
},
};
} else {
return {
start,
end,
value: {
x: 'center',
y: formatV(<Parsed<VerticalAlign>>keyword, firstLength),
},
};
}
}
} else {
const firstLength = parsePercentageOrLength(text, end);
if (firstLength) {
end = firstLength.end;
const secondLength = parsePercentageOrLength(text, end);
if (secondLength) {
end = secondLength.end;
return {
start,
end,
value: {
x: { align: 'left', offset: firstLength.value },
y: { align: 'top', offset: secondLength.value },
},
};
} else {
return {
start,
end,
value: {
x: { align: 'left', offset: firstLength.value },
y: 'center',
},
};
}
} else {
return null;
}
}
}
const directionRegEx = /\s*to\s*(left|right|top|bottom)\s*(left|right|top|bottom)?\s*/gy;
const sideDirections = {
top: (Math.PI * 0) / 2,
right: (Math.PI * 1) / 2,
bottom: (Math.PI * 2) / 2,
left: (Math.PI * 3) / 2,
};
const cornerDirections = {
top: {
right: (Math.PI * 1) / 4,
left: (Math.PI * 7) / 4,
},
right: {
top: (Math.PI * 1) / 4,
bottom: (Math.PI * 3) / 4,
},
bottom: {
right: (Math.PI * 3) / 4,
left: (Math.PI * 5) / 4,
},
left: {
top: (Math.PI * 7) / 4,
bottom: (Math.PI * 5) / 4,
},
};
function parseDirection(text: string, start = 0): Parsed<Angle> {
directionRegEx.lastIndex = start;
const result = directionRegEx.exec(text);
if (!result) {
return null;
}
const end = directionRegEx.lastIndex;
const firstDirection = result[1];
if (result[2]) {
const secondDirection = result[2];
const value = cornerDirections[firstDirection][secondDirection];
return value === undefined ? null : { start, end, value };
} else {
return { start, end, value: sideDirections[firstDirection] };
}
}
const openingBracketRegEx = /\s*\(\s*/gy;
const closingBracketRegEx = /\s*\)\s*/gy;
const closingBracketOrCommaRegEx = /\s*([),])\s*/gy;
function parseArgumentsList<T>(text: string, start: number, argument: (value: string, lastIndex: number, index: number) => Parsed<T>): Parsed<Parsed<T>[]> {
openingBracketRegEx.lastIndex = start;
const openingBracket = openingBracketRegEx.exec(text);
if (!openingBracket) {
return null;
}
let end = openingBracketRegEx.lastIndex;
const value: Parsed<T>[] = [];
closingBracketRegEx.lastIndex = end;
const closingBracket = closingBracketRegEx.exec(text);
if (closingBracket) {
return { start, end, value };
}
// eslint-disable-next-line no-constant-condition
for (let index = 0; true; index++) {
const arg = argument(text, end, index);
if (!arg) {
return null;
}
end = arg.end;
value.push(arg);
closingBracketOrCommaRegEx.lastIndex = end;
const closingBracketOrComma = closingBracketOrCommaRegEx.exec(text);
if (closingBracketOrComma) {
end = closingBracketOrCommaRegEx.lastIndex;
if (closingBracketOrComma[1] === ',') {
// noinspection UnnecessaryContinueJS
continue;
} else if (closingBracketOrComma[1] === ')') {
return { start, end, value };
}
} else {
return null;
}
}
}
export function parseColorStop(text: string, start = 0): Parsed<ColorStop> {
const color = parseColor(text, start);
if (!color) {
return null;
}
let end = color.end;
const offset = parsePercentageOrLength(text, end);
if (offset) {
end = offset.end;
return {
start,
end,
value: { color: color.value, offset: offset.value },
};
}
return { start, end, value: { color: color.value } };
}
const linearGradientStartRegEx = /\s*linear-gradient\s*/gy;
export function parseLinearGradient(text: string, start = 0): Parsed<LinearGradient> {
linearGradientStartRegEx.lastIndex = start;
const lgs = linearGradientStartRegEx.exec(text);
if (!lgs) {
return null;
}
let end = linearGradientStartRegEx.lastIndex;
let angle = Math.PI;
const colors: ColorStop[] = [];
const parsedArgs = parseArgumentsList<Angle | ColorStop>(text, end, (text, start, index) => {
if (index === 0) {
// First arg can be gradient direction
const angleArg = parseAngle(text, start) || parseDirection(text, start);
if (angleArg) {
angle = angleArg.value;
return angleArg;
}
}
const colorStop = parseColorStop(text, start);
if (colorStop) {
colors.push(colorStop.value);
return colorStop;
}
return null;
});
if (!parsedArgs) {
return null;
}
end = parsedArgs.end;
return { start, end, value: { angle, colors } };
}
const slashRegEx = /\s*(\/)\s*/gy;
function parseSlash(text: string, start: number): Parsed<'/'> {
slashRegEx.lastIndex = start;
const slash = slashRegEx.exec(text);
if (!slash) {
return null;
}
const end = slashRegEx.lastIndex;
return { start, end, value: '/' };
}
export function parseBackground(text: string, start = 0): Parsed<Background> {
const value: any = {};
let end = start;
while (end < text.length) {
const keyword = parseKeyword(text, end);
const color = parseColor(text, end, keyword);
if (color) {
value.color = color.value;
end = color.end;
continue;
}
const repeat = parseRepeat(text, end, keyword);
if (repeat) {
value.repeat = repeat.value;
end = repeat.end;
continue;
}
const position = parseBackgroundPosition(text, end, keyword);
if (position) {
position.value.text = text.substring(position.start, position.end);
value.position = position.value;
end = position.end;
const slash = parseSlash(text, end);
if (slash) {
end = slash.end;
const size = parseBackgroundSize(text, end);
if (!size) {
// Found / but no proper size following
return null;
}
value.size = size.value;
end = size.end;
}
continue;
}
const url = parseURL(text, end);
if (url) {
value.image = url.value;
end = url.end;
continue;
}
const gradient = parseLinearGradient(text, end);
if (gradient) {
value.image = gradient.value;
end = gradient.end;
continue;
}
return null;
}
return { start, end, value };
}
// Selectors
export type Combinator = '+' | '~' | '>' | ' ';
export interface UniversalSelector {
type: '*';
}
export interface TypeSelector {
type: '';
identifier: string;
}
export interface ClassSelector {
type: '.';
identifier: string;
}
export interface IdSelector {
type: '#';
identifier: string;
}
export interface PseudoClassSelector {
type: ':';
identifier: string;
}
export type AttributeSelectorTest = '=' | '^=' | '$=' | '*=' | '~=' | '|=';
export interface AttributeSelector {
type: '[]';
property: string;
test?: AttributeSelectorTest;
value?: string;
}
export type SimpleSelector = UniversalSelector | TypeSelector | ClassSelector | IdSelector | PseudoClassSelector | AttributeSelector;
export type SimpleSelectorSequence = SimpleSelector[];
export type SelectorCombinatorPair = [SimpleSelectorSequence, Combinator];
export type Selector = SelectorCombinatorPair[];
const universalSelectorRegEx = /\*/gy;
export function parseUniversalSelector(text: string, start = 0): Parsed<UniversalSelector> {
universalSelectorRegEx.lastIndex = start;
const result = universalSelectorRegEx.exec(text);
if (!result) {
return null;
}
const end = universalSelectorRegEx.lastIndex;
return { start, end, value: { type: '*' } };
}
const simpleIdentifierSelectorRegEx = /(#|\.|:|\b)((?:[\w_-]|\\.)(?:[\w\d_-]|\\.)*)/guy;
const unicodeEscapeRegEx = /\\([0-9a-fA-F]{1,5}\s|[0-9a-fA-F]{6})/g;
export function parseSimpleIdentifierSelector(text: string, start = 0): Parsed<TypeSelector | ClassSelector | IdSelector | PseudoClassSelector> {
simpleIdentifierSelectorRegEx.lastIndex = start;
const result = simpleIdentifierSelectorRegEx.exec(text.replace(unicodeEscapeRegEx, (_, c) => '\\' + String.fromCodePoint(parseInt(c.trim(), 16))));
if (!result) {
return null;
}
const end = simpleIdentifierSelectorRegEx.lastIndex;
const type = <'#' | '.' | ':' | ''>result[1];
const identifier: string = result[2].replace(/\\/g, '');
const value = <TypeSelector | ClassSelector | IdSelector | PseudoClassSelector>{ type, identifier };
return { start, end, value };
}
const attributeSelectorRegEx = /\[\s*([_\-\w][_\-\w\d]*)\s*(?:(=|\^=|\$=|\*=|\~=|\|=)\s*(?:([_\-\w][_\-\w\d]*)|"((?:[^\\"]|\\(?:"|n|r|f|\\|0-9a-f))*)"|'((?:[^\\']|\\(?:'|n|r|f|\\|0-9a-f))*)')\s*)?\]/gy;
export function parseAttributeSelector(text: string, start: number): Parsed<AttributeSelector> {
attributeSelectorRegEx.lastIndex = start;
const result = attributeSelectorRegEx.exec(text);
if (!result) {
return null;
}
const end = attributeSelectorRegEx.lastIndex;
const property = result[1];
if (result[2]) {
const test = <AttributeSelectorTest>result[2];
const value = result[3] || result[4] || result[5];
return { start, end, value: { type: '[]', property, test, value } };
}
return { start, end, value: { type: '[]', property } };
}
export function parseSimpleSelector(text: string, start = 0): Parsed<SimpleSelector> {
return parseUniversalSelector(text, start) || parseSimpleIdentifierSelector(text, start) || parseAttributeSelector(text, start);
}
export function parseSimpleSelectorSequence(text: string, start: number): Parsed<SimpleSelector[]> {
let simpleSelector = parseSimpleSelector(text, start);
if (!simpleSelector) {
return null;
}
let end = simpleSelector.end;
const value = <SimpleSelectorSequence>[];
while (simpleSelector) {
value.push(simpleSelector.value);
end = simpleSelector.end;
simpleSelector = parseSimpleSelector(text, end);
}
return { start, end, value };
}
const combinatorRegEx = /\s*([+~>])?\s*/gy;
export function parseCombinator(text: string, start = 0): Parsed<Combinator> {
combinatorRegEx.lastIndex = start;
const result = combinatorRegEx.exec(text);
if (!result) {
return null;
}
const end = combinatorRegEx.lastIndex;
const value = <Combinator>result[1] || ' ';
return { start, end, value };
}
const whiteSpaceRegEx = /\s*/gy;
export function parseSelector(text: string, start = 0): Parsed<Selector> {
let end = start;
whiteSpaceRegEx.lastIndex = end;
const leadingWhiteSpace = whiteSpaceRegEx.exec(text);
if (leadingWhiteSpace) {
end = whiteSpaceRegEx.lastIndex;
}
const value = <Selector>[];
let combinator: Parsed<Combinator>;
let expectSimpleSelector = true; // Must have at least one
let pair: SelectorCombinatorPair;
do {
const simpleSelectorSequence = parseSimpleSelectorSequence(text, end);
if (!simpleSelectorSequence) {
if (expectSimpleSelector) {
return null;
} else {
break;
}
}
end = simpleSelectorSequence.end;
if (combinator) {
// This logic looks weird; this `if` statement would occur on the next LOOP, so it effects the prior `pair`
// variable which is already pushed into the `value` array is going to have its `undefined` set to this
// value before the following statement creates a new `pair` memory variable.
// noinspection JSUnusedAssignment
pair[1] = combinator.value;
}
pair = [simpleSelectorSequence.value, undefined];
value.push(pair);
combinator = parseCombinator(text, end);
if (combinator) {
end = combinator.end;
}
expectSimpleSelector = combinator && combinator.value !== ' '; // Simple selector must follow non trailing white space combinator
} while (combinator);
return { start, end, value };
}