text: /* This Source Code Form is subject to the terms of the Mozilla Public
   * License, v. 2.0. If a copy of the MPL was not distributed with this
   * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
  
  "use strict";
  const {classes: Cc, interfaces: Ci, utils: Cu, results: Cr} = Components;
  
  this.EXPORTED_SYMBOLS = ["Windows8WindowFrameColor"];
  
  Cu.import("resource://gre/modules/Services.jsm");
  Cu.import("resource://gre/modules/XPCOMUtils.jsm");
  Cu.import("resource://gre/modules/WindowsRegistry.jsm");
  
  var Windows8WindowFrameColor = {
    _windowFrameColor: null,
  
    get_win8: function() {
      if (this._windowFrameColor)
        return this._windowFrameColor;
      
      const HKCU = Ci.nsIWindowsRegKey.ROOT_KEY_CURRENT_USER;
      const dwmKey = "Software\\Microsoft\\Windows\\DWM";
  
      // Window frame base color component values when Color Intensity is at 0.
      let frameBaseColor = 217;
      
      let windowFrameColor = WindowsRegistry.readRegKey(HKCU, dwmKey,
                                                        "ColorizationColor");
      if (windowFrameColor == undefined) {
        // Return the default color if unset or colorization not used
        return this._windowFrameColor = [frameBaseColor, frameBaseColor, frameBaseColor];
      }
      // The color returned from the Registry is in decimal form.
      let windowFrameColorHex = windowFrameColor.toString(16);
      // Zero-pad the number just to make sure that it is 8 digits.
      windowFrameColorHex = ("00000000" + windowFrameColorHex).substr(-8);
      let windowFrameColorArray = windowFrameColorHex.match(/../g);
      let [unused, fgR, fgG, fgB] = windowFrameColorArray.map(function(val) parseInt(val, 16));
      let windowFrameColorBalance = WindowsRegistry.readRegKey(HKCU, dwmKey,
                                                               "ColorizationColorBalance");
      // Default to balance=78 if reg key isn't defined
      if (windowFrameColorBalance == undefined) {
        windowFrameColorBalance = 78;
      }
      let alpha = windowFrameColorBalance / 100;
  
      // Alpha-blend the foreground color with the frame base color.
      let r = Math.round(fgR * alpha + frameBaseColor * (1 - alpha));
      let g = Math.round(fgG * alpha + frameBaseColor * (1 - alpha));
      let b = Math.round(fgB * alpha + frameBaseColor * (1 - alpha));
      return this._windowFrameColor = [r, g, b];
    }
  };
  