convert.ts

import { round } from "./round";
import { RgbaColor, RgbColor, HslaColor, HslColor, HsvaColor, HsvColor } from "../types";

/**
 * Valid CSS <angle> units.
 * https://developer.mozilla.org/en-US/docs/Web/CSS/angle
 */
const angleUnits: Record<string, number> = {
  grad: 360 / 400,
  turn: 360,
  rad: 360 / (Math.PI * 2),
};

export const hexToHsva = (hex: string): HsvaColor => rgbaToHsva(hexToRgba(hex));

export const hexToRgba = (hex: string): RgbaColor => {
  if (hex[0] === "#") hex = hex.substring(1);

  if (hex.length < 6) {
    return {
      r: parseInt(hex[0] + hex[0], 16),
      g: parseInt(hex[1] + hex[1], 16),
      b: parseInt(hex[2] + hex[2], 16),
      a: hex.length === 4 ? round(parseInt(hex[3] + hex[3], 16) / 255, 2) : 1,
    };
  }

  return {
    r: parseInt(hex.substring(0, 2), 16),
    g: parseInt(hex.substring(2, 4), 16),
    b: parseInt(hex.substring(4, 6), 16),
    a: hex.length === 8 ? round(parseInt(hex.substring(6, 8), 16) / 255, 2) : 1,
  };
};

export const parseHue = (value: string, unit = "deg"): number => {
  return Number(value) * (angleUnits[unit] || 1);
};

export const hslaStringToHsva = (hslString: string): HsvaColor => {
  const matcher = /hsla?\(?\s*(-?\d*\.?\d+)(deg|rad|grad|turn)?[,\s]+(-?\d*\.?\d+)%?[,\s]+(-?\d*\.?\d+)%?,?\s*[/\s]*(-?\d*\.?\d+)?(%)?\s*\)?/i;
  const match = matcher.exec(hslString);

  if (!match) return { h: 0, s: 0, v: 0, a: 1 };

  return hslaToHsva({
    h: parseHue(match[1], match[2]),
    s: Number(match[3]),
    l: Number(match[4]),
    a: match[5] === undefined ? 1 : Number(match[5]) / (match[6] ? 100 : 1),
  });
};

export const hslStringToHsva = hslaStringToHsva;

export const hslaToHsva = ({ h, s, l, a }: HslaColor): HsvaColor => {
  s *= (l < 50 ? l : 100 - l) / 100;

  return {
    h: h,
    s: s > 0 ? ((2 * s) / (l + s)) * 100 : 0,
    v: l + s,
    a,
  };
};

export const hsvaToHex = (hsva: HsvaColor): string => rgbaToHex(hsvaToRgba(hsva));

export const hsvaToHsla = ({ h, s, v, a }: HsvaColor): HslaColor => {
  const hh = ((200 - s) * v) / 100;

  return {
    h: round(h),
    s: round(hh > 0 && hh < 200 ? ((s * v) / 100 / (hh <= 100 ? hh : 200 - hh)) * 100 : 0),
    l: round(hh / 2),
    a: round(a, 2),
  };
};

export const hsvaToHslString = (hsva: HsvaColor): string => {
  const { h, s, l } = hsvaToHsla(hsva);
  return `hsl(${h}, ${s}%, ${l}%)`;
};

export const hsvaToHsvString = (hsva: HsvaColor): string => {
  const { h, s, v } = roundHsva(hsva);
  return `hsv(${h}, ${s}%, ${v}%)`;
};

export const hsvaToHsvaString = (hsva: HsvaColor): string => {
  const { h, s, v, a } = roundHsva(hsva);
  return `hsva(${h}, ${s}%, ${v}%, ${a})`;
};

export const hsvaToHslaString = (hsva: HsvaColor): string => {
  const { h, s, l, a } = hsvaToHsla(hsva);
  return `hsla(${h}, ${s}%, ${l}%, ${a})`;
};

export const hsvaToRgba = ({ h, s, v, a }: HsvaColor): RgbaColor => {
  h = (h / 360) * 6;
  s = s / 100;
  v = v / 100;

  const hh = Math.floor(h),
    b = v * (1 - s),
    c = v * (1 - (h - hh) * s),
    d = v * (1 - (1 - h + hh) * s),
    module = hh % 6;

  return {
    r: round([v, c, b, b, d, v][module] * 255),
    g: round([d, v, v, c, b, b][module] * 255),
    b: round([b, b, d, v, v, c][module] * 255),
    a: round(a, 2),
  };
};

export const hsvaToRgbString = (hsva: HsvaColor): string => {
  const { r, g, b } = hsvaToRgba(hsva);
  return `rgb(${r}, ${g}, ${b})`;
};

export const hsvaToRgbaString = (hsva: HsvaColor): string => {
  const { r, g, b, a } = hsvaToRgba(hsva);
  return `rgba(${r}, ${g}, ${b}, ${a})`;
};

export const hsvaStringToHsva = (hsvString: string): HsvaColor => {
  const matcher = /hsva?\(?\s*(-?\d*\.?\d+)(deg|rad|grad|turn)?[,\s]+(-?\d*\.?\d+)%?[,\s]+(-?\d*\.?\d+)%?,?\s*[/\s]*(-?\d*\.?\d+)?(%)?\s*\)?/i;
  const match = matcher.exec(hsvString);

  if (!match) return { h: 0, s: 0, v: 0, a: 1 };

  return roundHsva({
    h: parseHue(match[1], match[2]),
    s: Number(match[3]),
    v: Number(match[4]),
    a: match[5] === undefined ? 1 : Number(match[5]) / (match[6] ? 100 : 1),
  });
};

export const hsvStringToHsva = hsvaStringToHsva;

export const rgbaStringToHsva = (rgbaString: string): HsvaColor => {
  const matcher = /rgba?\(?\s*(-?\d*\.?\d+)(%)?[,\s]+(-?\d*\.?\d+)(%)?[,\s]+(-?\d*\.?\d+)(%)?,?\s*[/\s]*(-?\d*\.?\d+)?(%)?\s*\)?/i;
  const match = matcher.exec(rgbaString);

  if (!match) return { h: 0, s: 0, v: 0, a: 1 };

  return rgbaToHsva({
    r: Number(match[1]) / (match[2] ? 100 / 255 : 1),
    g: Number(match[3]) / (match[4] ? 100 / 255 : 1),
    b: Number(match[5]) / (match[6] ? 100 / 255 : 1),
    a: match[7] === undefined ? 1 : Number(match[7]) / (match[8] ? 100 : 1),
  });
};

export const rgbStringToHsva = rgbaStringToHsva;

const format = (number: number) => {
  const hex = number.toString(16);
  return hex.length < 2 ? "0" + hex : hex;
};

export const rgbaToHex = ({ r, g, b, a }: RgbaColor): string => {
  const alphaHex = a < 1 ? format(round(a * 255)) : "";
  return "#" + format(r) + format(g) + format(b) + alphaHex;
};

export const rgbaToHsva = ({ r, g, b, a }: RgbaColor): HsvaColor => {
  const max = Math.max(r, g, b);
  const delta = max - Math.min(r, g, b);

  // prettier-ignore
  const hh = delta
    ? max === r
      ? (g - b) / delta
      : max === g
        ? 2 + (b - r) / delta
        : 4 + (r - g) / delta
    : 0;

  return {
    h: round(60 * (hh < 0 ? hh + 6 : hh)),
    s: round(max ? (delta / max) * 100 : 0),
    v: round((max / 255) * 100),
    a,
  };
};

export const roundHsva = (hsva: HsvaColor): HsvaColor => ({
  h: round(hsva.h),
  s: round(hsva.s),
  v: round(hsva.v),
  a: round(hsva.a, 2),
});

export const rgbaToRgb = ({ r, g, b }: RgbaColor): RgbColor => ({ r, g, b });

export const hslaToHsl = ({ h, s, l }: HslaColor): HslColor => ({ h, s, l });

export const hsvaToHsv = (hsva: HsvaColor): HsvColor => {
  const { h, s, v } = roundHsva(hsva);
  return { h, s, v };
};

export const updateAlphaFromString = (color: string, alpha: number): string => {
  return color.replace(/\d+\.\d+\)/, `${alpha})`);
};

export const updateAlphaFromObject = <T extends RgbaColor | HslaColor | HsvaColor>(
  color: T,
  alpha: number
): T => {
  return Object.assign({}, color, { a: alpha });
};