@material-ui/core/styles/colorManipulator.js

"use strict";

Object.defineProperty(exports, "__esModule", {
  value: true
});
exports.hexToRgb = hexToRgb;
exports.rgbToHex = rgbToHex;
exports.hslToRgb = hslToRgb;
exports.decomposeColor = decomposeColor;
exports.recomposeColor = recomposeColor;
exports.getContrastRatio = getContrastRatio;
exports.getLuminance = getLuminance;
exports.emphasize = emphasize;
exports.fade = fade;
exports.darken = darken;
exports.lighten = lighten;

/* eslint-disable no-use-before-define */

/**
 * Returns a number whose value is limited to the given range.
 *
 * @param {number} value The value to be clamped
 * @param {number} min The lower boundary of the output range
 * @param {number} max The upper boundary of the output range
 * @returns {number} A number in the range [min, max]
 */
function clamp(value) {
  var min = arguments.length > 1 && arguments[1] !== undefined ? arguments[1] : 0;
  var max = arguments.length > 2 && arguments[2] !== undefined ? arguments[2] : 1;

  if (process.env.NODE_ENV !== 'production') {
    if (value < min || value > max) {
      console.error("Material-UI: the value provided ".concat(value, " is out of range [").concat(min, ", ").concat(max, "]."));
    }
  }

  if (value < min) {
    return min;
  }

  if (value > max) {
    return max;
  }

  return value;
}
/**
 * Converts a color from CSS hex format to CSS rgb format.
 *
 * @param {string} color - Hex color, i.e. #nnn or #nnnnnn
 * @returns {string} A CSS rgb color string
 */


function hexToRgb(color) {
  color = color.substr(1);
  var re = new RegExp(".{1,".concat(color.length / 3, "}"), 'g');
  var colors = color.match(re);

  if (colors && colors[0].length === 1) {
    colors = colors.map(function (n) {
      return n + n;
    });
  }

  return colors ? "rgb(".concat(colors.map(function (n) {
    return parseInt(n, 16);
  }).join(', '), ")") : '';
}

function intToHex(int) {
  var hex = int.toString(16);
  return hex.length === 1 ? "0".concat(hex) : hex;
}
/**
 * Converts a color from CSS rgb format to CSS hex format.
 *
 * @param {string} color - RGB color, i.e. rgb(n, n, n)
 * @returns {string} A CSS rgb color string, i.e. #nnnnnn
 */


function rgbToHex(color) {
  // Idempotent
  if (color.indexOf('#') === 0) {
    return color;
  }

  var _decomposeColor = decomposeColor(color),
      values = _decomposeColor.values;

  return "#".concat(values.map(function (n) {
    return intToHex(n);
  }).join(''));
}
/**
 * Converts a color from hsl format to rgb format.
 *
 * @param {string} color - HSL color values
 * @returns {string} rgb color values
 */


function hslToRgb(color) {
  color = decomposeColor(color);
  var _color = color,
      values = _color.values;
  var h = values[0];
  var s = values[1] / 100;
  var l = values[2] / 100;
  var a = s * Math.min(l, 1 - l);

  var f = function f(n) {
    var k = arguments.length > 1 && arguments[1] !== undefined ? arguments[1] : (n + h / 30) % 12;
    return l - a * Math.max(Math.min(k - 3, 9 - k, 1), -1);
  };

  var type = 'rgb';
  var rgb = [Math.round(f(0) * 255), Math.round(f(8) * 255), Math.round(f(4) * 255)];

  if (color.type === 'hsla') {
    type += 'a';
    rgb.push(values[3]);
  }

  return recomposeColor({
    type: type,
    values: rgb
  });
}
/**
 * Returns an object with the type and values of a color.
 *
 * Note: Does not support rgb % values.
 *
 * @param {string} color - CSS color, i.e. one of: #nnn, #nnnnnn, rgb(), rgba(), hsl(), hsla()
 * @returns {object} - A MUI color object: {type: string, values: number[]}
 */


function decomposeColor(color) {
  // Idempotent
  if (color.type) {
    return color;
  }

  if (color.charAt(0) === '#') {
    return decomposeColor(hexToRgb(color));
  }

  var marker = color.indexOf('(');
  var type = color.substring(0, marker);

  if (['rgb', 'rgba', 'hsl', 'hsla'].indexOf(type) === -1) {
    throw new Error(["Material-UI: unsupported `".concat(color, "` color."), 'We support the following formats: #nnn, #nnnnnn, rgb(), rgba(), hsl(), hsla().'].join('\n'));
  }

  var values = color.substring(marker + 1, color.length - 1).split(',');
  values = values.map(function (value) {
    return parseFloat(value);
  });
  return {
    type: type,
    values: values
  };
}
/**
 * Converts a color object with type and values to a string.
 *
 * @param {object} color - Decomposed color
 * @param {string} color.type - One of: 'rgb', 'rgba', 'hsl', 'hsla'
 * @param {array} color.values - [n,n,n] or [n,n,n,n]
 * @returns {string} A CSS color string
 */


function recomposeColor(color) {
  var type = color.type;
  var values = color.values;

  if (type.indexOf('rgb') !== -1) {
    // Only convert the first 3 values to int (i.e. not alpha)
    values = values.map(function (n, i) {
      return i < 3 ? parseInt(n, 10) : n;
    });
  } else if (type.indexOf('hsl') !== -1) {
    values[1] = "".concat(values[1], "%");
    values[2] = "".concat(values[2], "%");
  }

  return "".concat(type, "(").concat(values.join(', '), ")");
}
/**
 * Calculates the contrast ratio between two colors.
 *
 * Formula: https://www.w3.org/TR/WCAG20-TECHS/G17.html#G17-tests
 *
 * @param {string} foreground - CSS color, i.e. one of: #nnn, #nnnnnn, rgb(), rgba(), hsl(), hsla()
 * @param {string} background - CSS color, i.e. one of: #nnn, #nnnnnn, rgb(), rgba(), hsl(), hsla()
 * @returns {number} A contrast ratio value in the range 0 - 21.
 */


function getContrastRatio(foreground, background) {
  var lumA = getLuminance(foreground);
  var lumB = getLuminance(background);
  return (Math.max(lumA, lumB) + 0.05) / (Math.min(lumA, lumB) + 0.05);
}
/**
 * The relative brightness of any point in a color space,
 * normalized to 0 for darkest black and 1 for lightest white.
 *
 * Formula: https://www.w3.org/TR/WCAG20-TECHS/G17.html#G17-tests
 *
 * @param {string} color - CSS color, i.e. one of: #nnn, #nnnnnn, rgb(), rgba(), hsl(), hsla()
 * @returns {number} The relative brightness of the color in the range 0 - 1
 */


function getLuminance(color) {
  color = decomposeColor(color);
  var rgb = color.type === 'hsl' ? decomposeColor(hslToRgb(color)).values : color.values;
  rgb = rgb.map(function (val) {
    val /= 255; // normalized

    return val <= 0.03928 ? val / 12.92 : Math.pow((val + 0.055) / 1.055, 2.4);
  }); // Truncate at 3 digits

  return Number((0.2126 * rgb[0] + 0.7152 * rgb[1] + 0.0722 * rgb[2]).toFixed(3));
}
/**
 * Darken or lighten a color, depending on its luminance.
 * Light colors are darkened, dark colors are lightened.
 *
 * @param {string} color - CSS color, i.e. one of: #nnn, #nnnnnn, rgb(), rgba(), hsl(), hsla()
 * @param {number} coefficient=0.15 - multiplier in the range 0 - 1
 * @returns {string} A CSS color string. Hex input values are returned as rgb
 */


function emphasize(color) {
  var coefficient = arguments.length > 1 && arguments[1] !== undefined ? arguments[1] : 0.15;
  return getLuminance(color) > 0.5 ? darken(color, coefficient) : lighten(color, coefficient);
}
/**
 * Set the absolute transparency of a color.
 * Any existing alpha values are overwritten.
 *
 * @param {string} color - CSS color, i.e. one of: #nnn, #nnnnnn, rgb(), rgba(), hsl(), hsla()
 * @param {number} value - value to set the alpha channel to in the range 0 -1
 * @returns {string} A CSS color string. Hex input values are returned as rgb
 */


function fade(color, value) {
  color = decomposeColor(color);
  value = clamp(value);

  if (color.type === 'rgb' || color.type === 'hsl') {
    color.type += 'a';
  }

  color.values[3] = value;
  return recomposeColor(color);
}
/**
 * Darkens a color.
 *
 * @param {string} color - CSS color, i.e. one of: #nnn, #nnnnnn, rgb(), rgba(), hsl(), hsla()
 * @param {number} coefficient - multiplier in the range 0 - 1
 * @returns {string} A CSS color string. Hex input values are returned as rgb
 */


function darken(color, coefficient) {
  color = decomposeColor(color);
  coefficient = clamp(coefficient);

  if (color.type.indexOf('hsl') !== -1) {
    color.values[2] *= 1 - coefficient;
  } else if (color.type.indexOf('rgb') !== -1) {
    for (var i = 0; i < 3; i += 1) {
      color.values[i] *= 1 - coefficient;
    }
  }

  return recomposeColor(color);
}
/**
 * Lightens a color.
 *
 * @param {string} color - CSS color, i.e. one of: #nnn, #nnnnnn, rgb(), rgba(), hsl(), hsla()
 * @param {number} coefficient - multiplier in the range 0 - 1
 * @returns {string} A CSS color string. Hex input values are returned as rgb
 */


function lighten(color, coefficient) {
  color = decomposeColor(color);
  coefficient = clamp(coefficient);

  if (color.type.indexOf('hsl') !== -1) {
    color.values[2] += (100 - color.values[2]) * coefficient;
  } else if (color.type.indexOf('rgb') !== -1) {
    for (var i = 0; i < 3; i += 1) {
      color.values[i] += (255 - color.values[i]) * coefficient;
    }
  }

  return recomposeColor(color);
}