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: /*
michael@0:  * This module adjusts network priority for tabs in a way that gives 'important'
michael@0:  * tabs a higher priority. There are 3 levels of priority. Each is listed below
michael@0:  * with the priority adjustment used.
michael@0:  *
michael@0:  * Highest (-10): Selected tab in the focused window.
michael@0:  * Medium (0):    Background tabs in the focused window.
michael@0:  *                Selected tab in background windows.
michael@0:  * Lowest (+10):  Background tabs in background windows.
michael@0:  */
michael@0: 
michael@0: this.EXPORTED_SYMBOLS = ["trackBrowserWindow"];
michael@0: 
michael@0: const Ci = Components.interfaces;
michael@0: 
michael@0: Components.utils.import("resource://gre/modules/XPCOMUtils.jsm");
michael@0: 
michael@0: 
michael@0: // Lazy getters
michael@0: XPCOMUtils.defineLazyServiceGetter(this, "_focusManager",
michael@0:                                    "@mozilla.org/focus-manager;1",
michael@0:                                    "nsIFocusManager");
michael@0: 
michael@0: 
michael@0: // Constants
michael@0: const TAB_EVENTS = ["TabOpen", "TabSelect"];
michael@0: const WINDOW_EVENTS = ["activate", "unload"];
michael@0: // PRIORITY DELTA is -10 because lower priority value is actually a higher priority
michael@0: const PRIORITY_DELTA = -10;
michael@0: 
michael@0: 
michael@0: // Variables
michael@0: let _lastFocusedWindow = null;
michael@0: let _windows = [];
michael@0: 
michael@0: 
michael@0: // Exported symbol
michael@0: this.trackBrowserWindow = function trackBrowserWindow(aWindow) {
michael@0:   WindowHelper.addWindow(aWindow);
michael@0: }
michael@0: 
michael@0: 
michael@0: // Global methods
michael@0: function _handleEvent(aEvent) {
michael@0:   switch (aEvent.type) {
michael@0:     case "TabOpen":
michael@0:       BrowserHelper.onOpen(aEvent.target.linkedBrowser);
michael@0:       break;
michael@0:     case "TabSelect":
michael@0:       BrowserHelper.onSelect(aEvent.target.linkedBrowser);
michael@0:       break;
michael@0:     case "activate":
michael@0:       WindowHelper.onActivate(aEvent.target);
michael@0:       break;
michael@0:     case "unload":
michael@0:       WindowHelper.removeWindow(aEvent.currentTarget);
michael@0:       break;
michael@0:   }
michael@0: }
michael@0: 
michael@0: 
michael@0: // Methods that impact a browser. Put into single object for organization.
michael@0: let BrowserHelper = {
michael@0:   onOpen: function NP_BH_onOpen(aBrowser) {
michael@0:     // If the tab is in the focused window, leave priority as it is
michael@0:     if (aBrowser.ownerDocument.defaultView != _lastFocusedWindow)
michael@0:       this.decreasePriority(aBrowser);
michael@0:   },
michael@0: 
michael@0:   onSelect: function NP_BH_onSelect(aBrowser) {
michael@0:     let windowEntry = WindowHelper.getEntry(aBrowser.ownerDocument.defaultView);
michael@0:     if (windowEntry.lastSelectedBrowser)
michael@0:       this.decreasePriority(windowEntry.lastSelectedBrowser);
michael@0:     this.increasePriority(aBrowser);
michael@0: 
michael@0:     windowEntry.lastSelectedBrowser = aBrowser;
michael@0:   },
michael@0: 
michael@0:   increasePriority: function NP_BH_increasePriority(aBrowser) {
michael@0:     aBrowser.adjustPriority(PRIORITY_DELTA);
michael@0:   },
michael@0: 
michael@0:   decreasePriority: function NP_BH_decreasePriority(aBrowser) {
michael@0:     aBrowser.adjustPriority(PRIORITY_DELTA * -1);
michael@0:   }
michael@0: };
michael@0: 
michael@0: 
michael@0: // Methods that impact a window. Put into single object for organization.
michael@0: let WindowHelper = {
michael@0:   addWindow: function NP_WH_addWindow(aWindow) {
michael@0:     // Build internal data object
michael@0:     _windows.push({ window: aWindow, lastSelectedBrowser: null });
michael@0: 
michael@0:     // Add event listeners
michael@0:     TAB_EVENTS.forEach(function(event) {
michael@0:       aWindow.gBrowser.tabContainer.addEventListener(event, _handleEvent, false);
michael@0:     });
michael@0:     WINDOW_EVENTS.forEach(function(event) {
michael@0:       aWindow.addEventListener(event, _handleEvent, false);
michael@0:     });
michael@0: 
michael@0:     // This gets called AFTER activate event, so if this is the focused window
michael@0:     // we want to activate it. Otherwise, deprioritize it.
michael@0:     if (aWindow == _focusManager.activeWindow)
michael@0:       this.handleFocusedWindow(aWindow);
michael@0:     else
michael@0:       this.decreasePriority(aWindow);
michael@0: 
michael@0:     // Select the selected tab
michael@0:     BrowserHelper.onSelect(aWindow.gBrowser.selectedBrowser);
michael@0:   },
michael@0: 
michael@0:   removeWindow: function NP_WH_removeWindow(aWindow) {
michael@0:     if (aWindow == _lastFocusedWindow)
michael@0:       _lastFocusedWindow = null;
michael@0: 
michael@0:     // Delete this window from our tracking
michael@0:     _windows.splice(this.getEntryIndex(aWindow), 1);
michael@0: 
michael@0:     // Remove the event listeners
michael@0:     TAB_EVENTS.forEach(function(event) {
michael@0:       aWindow.gBrowser.tabContainer.removeEventListener(event, _handleEvent, false);
michael@0:     });
michael@0:     WINDOW_EVENTS.forEach(function(event) {
michael@0:       aWindow.removeEventListener(event, _handleEvent, false);
michael@0:     });
michael@0:   },
michael@0: 
michael@0:   onActivate: function NP_WH_onActivate(aWindow, aHasFocus) {
michael@0:     // If this window was the last focused window, we don't need to do anything
michael@0:     if (aWindow == _lastFocusedWindow)
michael@0:       return;
michael@0: 
michael@0:     // handleFocusedWindow will deprioritize the current window
michael@0:     this.handleFocusedWindow(aWindow);
michael@0: 
michael@0:     // Lastly we should increase priority for this window
michael@0:     this.increasePriority(aWindow);
michael@0:   },
michael@0: 
michael@0:   handleFocusedWindow: function NP_WH_handleFocusedWindow(aWindow) {
michael@0:     // If we have a last focused window, we need to deprioritize it first
michael@0:     if (_lastFocusedWindow)
michael@0:       this.decreasePriority(_lastFocusedWindow);
michael@0: 
michael@0:     // aWindow is now focused
michael@0:     _lastFocusedWindow = aWindow;
michael@0:   },
michael@0: 
michael@0:   // Auxiliary methods
michael@0:   increasePriority: function NP_WH_increasePriority(aWindow) {
michael@0:     aWindow.gBrowser.browsers.forEach(function(aBrowser) {
michael@0:       BrowserHelper.increasePriority(aBrowser);
michael@0:     });
michael@0:   },
michael@0: 
michael@0:   decreasePriority: function NP_WH_decreasePriority(aWindow) {
michael@0:     aWindow.gBrowser.browsers.forEach(function(aBrowser) {
michael@0:       BrowserHelper.decreasePriority(aBrowser);
michael@0:     });
michael@0:   },
michael@0: 
michael@0:   getEntry: function NP_WH_getEntry(aWindow) {
michael@0:     return _windows[this.getEntryIndex(aWindow)];
michael@0:   },
michael@0: 
michael@0:   getEntryIndex: function NP_WH_getEntryAtIndex(aWindow) {
michael@0:     // Assumes that every object has a unique window & it's in the array
michael@0:     for (let i = 0; i < _windows.length; i++)
michael@0:       if (_windows[i].window == aWindow)
michael@0:         return i;
michael@0:   }
michael@0: };
michael@0: