index.js

'use strict';

Object.defineProperty(exports, "__esModule", {
  value: true
});

/**
 * This will take a HEX or RGB web color. pSBC can shade it darker or lighter,
 * or blend it with a second color, and can also pass it right thru but convert
 * from Hex to RGB (Hex2RGB) or RGB to Hex (RGB2Hex).
 * All without you even knowing what color format you are using.
 *
 * Docs: https://github.com/PimpTrizkit/PJs/wiki/12.-Shade,-Blend-and-Convert-a-Web-Color-(pSBC.js)#stackoverflow-archive-begin
 * 
 * @param {number} p - From -1.0 to 1.0 Positive numbers will shade to white (lighten the color). Negative colors will shade to black (darken the color). To convert use 0 adn "c" on c1. (Required)
 * @param {string} c0 - RGB or Hex. (Required)
 * @param {string} c1 - RGB, RGBA or HEX. Use "c" to convert. Using this will enable the blender. (Optional).
 * @param {string} l - Defaults to false. And will use Log Blending. Pass in true to use Linear Blending. (Optional).
 * @returns {string|null} Either Hex or RGB color. Null if invalid color or percentage number.
 */

exports.default = (p, c0, c1, l) => {
  let r, g, b, P, f, t, h, i = parseInt,
    m = Math.round,
    a = typeof (c1) == "string";
  if (typeof (p) != "number" || p < -1 || p > 1 || typeof (c0) != "string" || (c0[0] != 'r' && c0[0] != '#') || (c1 && !a)) return null;
  if (!this.pSBCr) this.pSBCr = (d) => {
    let n = d.length,
      x = {};
    if (n > 9) {
      [r, g, b, a] = d = d.split(","), n = d.length;
      if (n < 3 || n > 4) return null;
      x.r = i(r[3] == "a" ? r.slice(5) : r.slice(4)), x.g = i(g), x.b = i(b), x.a = a ? parseFloat(a) : -1
    } else {
      if (n == 8 || n == 6 || n < 4) return null;
      if (n < 6) d = "#" + d[1] + d[1] + d[2] + d[2] + d[3] + d[3] + (n > 4 ? d[4] + d[4] : "");
      d = i(d.slice(1), 16);
      if (n == 9 || n == 5) x.r = d >> 24 & 255, x.g = d >> 16 & 255, x.b = d >> 8 & 255, x.a = m((d & 255) / 0.255) / 1000;
      else x.r = d >> 16, x.g = d >> 8 & 255, x.b = d & 255, x.a = -1
    }
    return x
  };
  h = c0.length > 9, h = a ? c1.length > 9 ? true : c1 == "c" ? !h : false : h, f = this.pSBCr(c0), P = p < 0, t = c1 && c1 != "c" ? this.pSBCr(c1) : P ? {
    r: 0,
    g: 0,
    b: 0,
    a: -1
  } : {
      r: 255,
      g: 255,
      b: 255,
      a: -1
    }, p = P ? p * -1 : p, P = 1 - p;
  if (!f || !t) return null;
  if (l) r = m(P * f.r + p * t.r), g = m(P * f.g + p * t.g), b = m(P * f.b + p * t.b);
  else r = m((P * f.r ** 2 + p * t.r ** 2) ** 0.5), g = m((P * f.g ** 2 + p * t.g ** 2) ** 0.5), b = m((P * f.b ** 2 + p * t.b ** 2) ** 0.5);
  a = f.a, t = t.a, f = a >= 0 || t >= 0, a = f ? a < 0 ? t : t < 0 ? a : a * P + t * p : 0;
  if (h) return "rgb" + (f ? "a(" : "(") + r + "," + g + "," + b + (f ? "," + m(a * 1000) / 1000 : "") + ")";
  else return "#" + (4294967296 + r * 16777216 + g * 65536 + b * 256 + (f ? m(a * 255) : 0)).toString(16).slice(1, f ? undefined : -2)
}