Function parseColor

packages/backend/src/nearest-color/nearestColor.ts:151–184

* Parses a color from a string. * * @private * @param {RGB|string} source * @return {RGB} * * @example * parseColor({ r: 3, g: 22, b: 111 }); // => { r: 3, g: 22, b: 111 } * parseColor('#f00'); // => { r: 255, g: 0, b: 0 } * parseColor('#04fbc8'); // => { r: 4

(source: RGB | string)

 * parseColor('foo');                   // => throws
 */
function parseColor(source: RGB | string): RGB {
  let red, green, blue;

  if (typeof source === "object") {
    return source;
  }

  let hexMatchArr = source.match(/^#?((?:[0-9a-f]{3}){1,2})$/i);
  if (hexMatchArr) {
    const hexMatch = hexMatchArr[1];

    if (hexMatch.length === 3) {
      hexMatchArr = [
        hexMatch.charAt(0) + hexMatch.charAt(0),
        hexMatch.charAt(1) + hexMatch.charAt(1),
        hexMatch.charAt(2) + hexMatch.charAt(2),
      ];
    } else {
      hexMatchArr = [
        hexMatch.substring(0, 2),
        hexMatch.substring(2, 4),
        hexMatch.substring(4, 6),
      ];
    }

    red = parseInt(hexMatchArr[0], 16);
    green = parseInt(hexMatchArr[1], 16);
    blue = parseInt(hexMatchArr[2], 16);

    return { r: red, g: green, b: blue };
  }

  throw Error(`"${source}" is not a valid color`);
}

/**
 * Creates a {@link ColorSpec} from either a string or an {@link RGB}.