The Tor Browser / file revision

 /* 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/. */

 this.EXPORTED_SYMBOLS = ["LightweightThemeConsumer"];

 Components.utils.import("resource://gre/modules/XPCOMUtils.jsm");

 Components.utils.import("resource://gre/modules/Services.jsm");

 XPCOMUtils.defineLazyModuleGetter(this, "LightweightThemeImageOptimizer",

   "resource://gre/modules/addons/LightweightThemeImageOptimizer.jsm");

 XPCOMUtils.defineLazyModuleGetter(this, "PrivateBrowsingUtils",

   "resource://gre/modules/PrivateBrowsingUtils.jsm");

 this.LightweightThemeConsumer =

  function LightweightThemeConsumer(aDocument) {

   this._doc = aDocument;

   this._win = aDocument.defaultView;

   this._footerId = aDocument.documentElement.getAttribute("lightweightthemesfooter");

   if (PrivateBrowsingUtils.isWindowPrivate(this._win) &&

       !PrivateBrowsingUtils.permanentPrivateBrowsing) {

     return;

   }

   let screen = this._win.screen;

   this._lastScreenWidth = screen.width;

   this._lastScreenHeight = screen.height;

   Components.classes["@mozilla.org/observer-service;1"]

             .getService(Components.interfaces.nsIObserverService)

             .addObserver(this, "lightweight-theme-styling-update", false);

   var temp = {};

   Components.utils.import("resource://gre/modules/LightweightThemeManager.jsm", temp);

   this._update(temp.LightweightThemeManager.currentThemeForDisplay);

   this._win.addEventListener("resize", this);

 }

 LightweightThemeConsumer.prototype = {

   _lastData: null,

   _lastScreenWidth: null,

   _lastScreenHeight: null,

   // Whether the active lightweight theme should be shown on the window.

   _enabled: true,

   // Whether a lightweight theme is enabled.

   _active: false,

   enable: function() {

     this._enabled = true;

     this._update(this._lastData);

   },

   disable: function() {

     // Dance to keep the data, but reset the applied styles:

     let lastData = this._lastData

     this._update(null);

     this._enabled = false;

     this._lastData = lastData;

   },

   observe: function (aSubject, aTopic, aData) {

     if (aTopic != "lightweight-theme-styling-update")

       return;

     this._update(JSON.parse(aData));

   },

   handleEvent: function (aEvent) {

     let {width, height} = this._win.screen;

     if (this._lastScreenWidth != width || this._lastScreenHeight != height) {

       this._lastScreenWidth = width;

       this._lastScreenHeight = height;

       if (!this._active)

         return;

       this._update(this._lastData);

       Services.obs.notifyObservers(this._win, "lightweight-theme-optimized",

                                    JSON.stringify(this._lastData));

     }

   },

   destroy: function () {

     if (!PrivateBrowsingUtils.isWindowPrivate(this._win) ||

         PrivateBrowsingUtils.permanentPrivateBrowsing) {

       Components.classes["@mozilla.org/observer-service;1"]

                 .getService(Components.interfaces.nsIObserverService)

                 .removeObserver(this, "lightweight-theme-styling-update");

       this._win.removeEventListener("resize", this);

     }

     this._win = this._doc = null;

   },

   _update: function (aData) {

     if (!aData) {

       aData = { headerURL: "", footerURL: "", textcolor: "", accentcolor: "" };

       this._lastData = aData;

     } else {

       this._lastData = aData;

       aData = LightweightThemeImageOptimizer.optimize(aData, this._win.screen);

     }

     if (!this._enabled)

       return;

     let root = this._doc.documentElement;

     let active = !!aData.headerURL;

     let stateChanging = (active != this._active);

     if (active) {

       root.style.color = aData.textcolor || "black";

       root.style.backgroundColor = aData.accentcolor || "white";

       let [r, g, b] = _parseRGB(this._doc.defaultView.getComputedStyle(root, "").color);

       let luminance = 0.2125 * r + 0.7154 * g + 0.0721 * b;

       root.setAttribute("lwthemetextcolor", luminance <= 110 ? "dark" : "bright");

       root.setAttribute("lwtheme", "true");

     } else {

       root.style.color = "";

       root.style.backgroundColor = "";

       root.removeAttribute("lwthemetextcolor");

       root.removeAttribute("lwtheme");

     }

     this._active = active;

     _setImage(root, active, aData.headerURL);

     if (this._footerId) {

       let footer = this._doc.getElementById(this._footerId);

       footer.style.backgroundColor = active ? aData.accentcolor || "white" : "";

       _setImage(footer, active, aData.footerURL);

       if (active && aData.footerURL)

         footer.setAttribute("lwthemefooter", "true");

       else

         footer.removeAttribute("lwthemefooter");

     }

 #ifdef XP_MACOSX

     // On OS X, we extend the lightweight theme into the titlebar, which means setting

     // the chromemargin attribute. Some XUL applications already draw in the titlebar,

     // so we need to save the chromemargin value before we overwrite it with the value

     // that lets us draw in the titlebar. We stash this value on the root attribute so

     // that XUL applications have the ability to invalidate the saved value.

     if (stateChanging) {

       if (!root.hasAttribute("chromemargin-nonlwtheme")) {

         root.setAttribute("chromemargin-nonlwtheme", root.getAttribute("chromemargin"));

       }

       if (active) {

         root.setAttribute("chromemargin", "0,-1,-1,-1");

       } else {

         let defaultChromemargin = root.getAttribute("chromemargin-nonlwtheme");

         if (defaultChromemargin) {

           root.setAttribute("chromemargin", defaultChromemargin);

         } else {

           root.removeAttribute("chromemargin");

         }

       }

     }

 #endif

   }

 }

 function _setImage(aElement, aActive, aURL) {

   aElement.style.backgroundImage =

     (aActive && aURL) ? 'url("' + aURL.replace(/"/g, '\\"') + '")' : "";

 }

 function _parseRGB(aColorString) {

   var rgb = aColorString.match(/^rgba?\((\d+), (\d+), (\d+)/);

   rgb.shift();

   return rgb.map(function (x) parseInt(x));

 }