colorConverter.js

/**
 * Convert rgb formatted color string to hash formatted color string
 *
 * @example
 * // @returns #ff00ff
 * rgb2hash('rgb(255, 0, 255)');
 *
 * @param {string} rgbColorStr The rgb formatted color string
 * @returns {string} Returns the hash formatted color string
 */
var rgb2hash = function (rgbColorStr) {
  var str = '' + (rgbColorStr || '');
  var rgb = [];
  var r, g, b;

  // remove `rgb(`
  str = str.replace(/^\s*rgb\s*\(\s*/, '');
  // remove `)`
  str = str.replace(/\s*\)\s*$/, '');
  // spilt by `,`
  rgb = str.split(/\s*\,\s*/);

  r = (parseInt(rgb[0] || 0) || 0).toString(16);
  g = (parseInt(rgb[1] || 0) || 0).toString(16);
  b = (parseInt(rgb[2] || 0) || 0).toString(16);

  r = r.length < 2 ? ('0' + r) : r;
  g = g.length < 2 ? ('0' + g) : g;
  b = b.length < 2 ? ('0' + b) : b;

  return '#' + r + g + b;
};

/**
 * Convert the hash formatted color string to rgb formatted color string
 *
 * @example
 * // Returns rgb(204, 204, 204)
 * hash2rgb('#cccccc');
 * // Returns rgb(238, 238, 238)
 * hash2rgb('#eee');
 *
 * @param {string} hashColorStr The hash formatted color string
 * @returns {string} Returns the rgb formatted color string
 */
var hash2rgb = function (hashColorStr) {
  var str = '' + (hashColorStr || '');
  var r, g, b;

  str = str.replace(/^\s*#\s*/, '');
  str = str.replace(/\s*$/, '');

  if (str.length === 3) {
    r = str.substr(0, 1);
    g = str.substr(1, 1);
    b = str.substr(2, 1);
    r += r;
    g += g;
    b += b;
  } else {
    r = str.substr(0, 2);
    g = str.substr(2, 2);
    b = str.substr(4, 2);
  }

  r = parseInt(r, 16) || 0;
  g = parseInt(g, 16) || 0;
  b = parseInt(b, 16) || 0;

  return 'rgb(' + r + ', ' + g + ', ' + b + ')';
};