michael@0: /* This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this
michael@0:  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: 
michael@0: "use strict";
michael@0: 
michael@0: const { classes: Cc, interfaces: Ci, utils: Cu } = Components;
michael@0: 
michael@0: this.EXPORTED_SYMBOLS = [ "switchToFloatingScrollbars", "switchToNativeScrollbars" ];
michael@0: 
michael@0: Cu.import("resource://gre/modules/Services.jsm");
michael@0: 
michael@0: let URL = Services.io.newURI("chrome://browser/skin/devtools/floating-scrollbars.css", null, null);
michael@0: 
michael@0: let trackedTabs = new WeakMap();
michael@0: 
michael@0: /**
michael@0:  * Switch to floating scrollbars, à la mobile.
michael@0:  *
michael@0:  * @param aTab the targeted tab.
michael@0:  *
michael@0:  */
michael@0: this.switchToFloatingScrollbars = function switchToFloatingScrollbars(aTab) {
michael@0:   let mgr = trackedTabs.get(aTab);
michael@0:   if (!mgr) {
michael@0:     mgr = new ScrollbarManager(aTab);
michael@0:   }
michael@0:   mgr.switchToFloating();
michael@0: }
michael@0: 
michael@0: /**
michael@0:  * Switch to original native scrollbars.
michael@0:  *
michael@0:  * @param aTab the targeted tab.
michael@0:  *
michael@0:  */
michael@0: this.switchToNativeScrollbars = function switchToNativeScrollbars(aTab) {
michael@0:   let mgr = trackedTabs.get(aTab);
michael@0:   if (mgr) {
michael@0:     mgr.reset();
michael@0:   }
michael@0: }
michael@0: 
michael@0: function ScrollbarManager(aTab) {
michael@0:   trackedTabs.set(aTab, this);
michael@0: 
michael@0:   this.attachedTab = aTab;
michael@0:   this.attachedBrowser = aTab.linkedBrowser;
michael@0: 
michael@0:   this.reset = this.reset.bind(this);
michael@0:   this.switchToFloating = this.switchToFloating.bind(this);
michael@0: 
michael@0:   this.attachedTab.addEventListener("TabClose", this.reset, true);
michael@0:   this.attachedBrowser.addEventListener("DOMContentLoaded", this.switchToFloating, true);
michael@0: }
michael@0: 
michael@0: ScrollbarManager.prototype = {
michael@0:   get win() {
michael@0:     return this.attachedBrowser.contentWindow;
michael@0:   },
michael@0: 
michael@0:   /*
michael@0:    * Change the look of the scrollbars.
michael@0:    */
michael@0:   switchToFloating: function() {
michael@0:     let windows = this.getInnerWindows(this.win);
michael@0:     windows.forEach(this.injectStyleSheet);
michael@0:     this.forceStyle();
michael@0:   },
michael@0: 
michael@0: 
michael@0:   /*
michael@0:    * Reset the look of the scrollbars.
michael@0:    */
michael@0:   reset: function() {
michael@0:     let windows = this.getInnerWindows(this.win);
michael@0:     windows.forEach(this.removeStyleSheet);
michael@0:     this.forceStyle(this.attachedBrowser);
michael@0:     this.attachedBrowser.removeEventListener("DOMContentLoaded", this.switchToFloating, true);
michael@0:     this.attachedTab.removeEventListener("TabClose", this.reset, true);
michael@0:     trackedTabs.delete(this.attachedTab);
michael@0:   },
michael@0: 
michael@0:   /*
michael@0:    * Toggle the display property of the window to force the style to be applied.
michael@0:    */
michael@0:   forceStyle: function() {
michael@0:     let parentWindow = this.attachedBrowser.ownerDocument.defaultView;
michael@0:     let display = parentWindow.getComputedStyle(this.attachedBrowser).display; // Save display value
michael@0:     this.attachedBrowser.style.display = "none";
michael@0:     parentWindow.getComputedStyle(this.attachedBrowser).display; // Flush
michael@0:     this.attachedBrowser.style.display = display; // Restore
michael@0:   },
michael@0: 
michael@0:   /*
michael@0:    * return all the window objects present in the hiearchy of a window.
michael@0:    */
michael@0:   getInnerWindows: function(win) {
michael@0:     let iframes = win.document.querySelectorAll("iframe");
michael@0:     let innerWindows = [];
michael@0:     for (let iframe of iframes) {
michael@0:       innerWindows = innerWindows.concat(this.getInnerWindows(iframe.contentWindow));
michael@0:     }
michael@0:     return [win].concat(innerWindows);
michael@0:   },
michael@0: 
michael@0:   /*
michael@0:    * Append the new scrollbar style.
michael@0:    */
michael@0:   injectStyleSheet: function(win) {
michael@0:     let winUtils = win.QueryInterface(Ci.nsIInterfaceRequestor).getInterface(Ci.nsIDOMWindowUtils);
michael@0:     try {
michael@0:       winUtils.loadSheet(URL, win.AGENT_SHEET);
michael@0:     }catch(e) {}
michael@0:   },
michael@0: 
michael@0:   /*
michael@0:    * Remove the injected stylesheet.
michael@0:    */
michael@0:   removeStyleSheet: function(win) {
michael@0:     let winUtils = win.QueryInterface(Ci.nsIInterfaceRequestor).getInterface(Ci.nsIDOMWindowUtils);
michael@0:     try {
michael@0:       winUtils.removeSheet(URL, win.AGENT_SHEET);
michael@0:     }catch(e) {}
michael@0:   },
michael@0: }