michael@0: /* -*- Mode: JavaScript; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
michael@0:  * vim: sw=2 ts=2 sts=2 et filetype=javascript
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: this.EXPORTED_SYMBOLS = [
michael@0:   "DownloadTaskbarProgress",
michael@0: ];
michael@0: 
michael@0: ////////////////////////////////////////////////////////////////////////////////
michael@0: //// Constants
michael@0: 
michael@0: const Cc = Components.classes;
michael@0: const Ci = Components.interfaces;
michael@0: const Cu = Components.utils;
michael@0: const Cr = Components.results;
michael@0: 
michael@0: Cu.import("resource://gre/modules/XPCOMUtils.jsm");
michael@0: XPCOMUtils.defineLazyModuleGetter(this, "Services",
michael@0:                                   "resource://gre/modules/Services.jsm");
michael@0: 
michael@0: const kTaskbarIDWin = "@mozilla.org/windows-taskbar;1";
michael@0: const kTaskbarIDMac = "@mozilla.org/widget/macdocksupport;1";
michael@0: 
michael@0: ////////////////////////////////////////////////////////////////////////////////
michael@0: //// DownloadTaskbarProgress Object
michael@0: 
michael@0: this.DownloadTaskbarProgress =
michael@0: {
michael@0:   init: function DTP_init()
michael@0:   {
michael@0:     if (DownloadTaskbarProgressUpdater) {
michael@0:       DownloadTaskbarProgressUpdater._init();
michael@0:     }
michael@0:   },
michael@0: 
michael@0:   /**
michael@0:    * Called when a browser window appears. This has an effect only when we
michael@0:    * don't already have an active window.
michael@0:    *
michael@0:    * @param aWindow
michael@0:    *        The browser window that we'll potentially use to display the
michael@0:    *        progress.
michael@0:    */
michael@0:   onBrowserWindowLoad: function DTP_onBrowserWindowLoad(aWindow)
michael@0:   {
michael@0:     this.init();
michael@0:     if (!DownloadTaskbarProgressUpdater) {
michael@0:       return;
michael@0:     }
michael@0:     if (!DownloadTaskbarProgressUpdater._activeTaskbarProgress) {
michael@0:       DownloadTaskbarProgressUpdater._setActiveWindow(aWindow, false);
michael@0:     }
michael@0:   },
michael@0: 
michael@0:   /**
michael@0:    * Called when the download window appears. The download window will take
michael@0:    * over as the active window.
michael@0:    */
michael@0:   onDownloadWindowLoad: function DTP_onDownloadWindowLoad(aWindow)
michael@0:   {
michael@0:     if (!DownloadTaskbarProgressUpdater) {
michael@0:       return;
michael@0:     }
michael@0:     DownloadTaskbarProgressUpdater._setActiveWindow(aWindow, true);
michael@0:   },
michael@0: 
michael@0:   /**
michael@0:    * Getters for internal DownloadTaskbarProgressUpdater values
michael@0:    */
michael@0: 
michael@0:   get activeTaskbarProgress() {
michael@0:     if (!DownloadTaskbarProgressUpdater) {
michael@0:       return null;
michael@0:     }
michael@0:     return DownloadTaskbarProgressUpdater._activeTaskbarProgress;
michael@0:   },
michael@0: 
michael@0:   get activeWindowIsDownloadWindow() {
michael@0:     if (!DownloadTaskbarProgressUpdater) {
michael@0:       return null;
michael@0:     }
michael@0:     return DownloadTaskbarProgressUpdater._activeWindowIsDownloadWindow;
michael@0:   },
michael@0: 
michael@0:   get taskbarState() {
michael@0:     if (!DownloadTaskbarProgressUpdater) {
michael@0:       return null;
michael@0:     }
michael@0:     return DownloadTaskbarProgressUpdater._taskbarState;
michael@0:   },
michael@0: 
michael@0: };
michael@0: 
michael@0: ////////////////////////////////////////////////////////////////////////////////
michael@0: //// DownloadTaskbarProgressUpdater Object
michael@0: 
michael@0: var DownloadTaskbarProgressUpdater =
michael@0: {
michael@0:   /// Whether the taskbar is initialized.
michael@0:   _initialized: false,
michael@0: 
michael@0:   /// Reference to the taskbar.
michael@0:   _taskbar: null,
michael@0: 
michael@0:   /// Reference to the download manager.
michael@0:   _dm: null,
michael@0: 
michael@0:   /**
michael@0:    * Initialize and register ourselves as a download progress listener.
michael@0:    */
michael@0:   _init: function DTPU_init()
michael@0:   {
michael@0:     if (this._initialized) {
michael@0:       return; // Already initialized
michael@0:     }
michael@0:     this._initialized = true;
michael@0: 
michael@0:     if (kTaskbarIDWin in Cc) {
michael@0:       this._taskbar = Cc[kTaskbarIDWin].getService(Ci.nsIWinTaskbar);
michael@0:       if (!this._taskbar.available) {
michael@0:         // The Windows version is probably too old
michael@0:         DownloadTaskbarProgressUpdater = null;
michael@0:         return;
michael@0:       }
michael@0:     } else if (kTaskbarIDMac in Cc) {
michael@0:       this._activeTaskbarProgress = Cc[kTaskbarIDMac].
michael@0:                                       getService(Ci.nsITaskbarProgress);
michael@0:     } else {
michael@0:       DownloadTaskbarProgressUpdater = null;
michael@0:       return;
michael@0:     }
michael@0: 
michael@0:     this._taskbarState = Ci.nsITaskbarProgress.STATE_NO_PROGRESS;
michael@0: 
michael@0:     this._dm = Cc["@mozilla.org/download-manager;1"].
michael@0:                getService(Ci.nsIDownloadManager);
michael@0:     this._dm.addPrivacyAwareListener(this);
michael@0: 
michael@0:     this._os = Cc["@mozilla.org/observer-service;1"].
michael@0:                getService(Ci.nsIObserverService);
michael@0:     this._os.addObserver(this, "quit-application-granted", false);
michael@0: 
michael@0:     this._updateStatus();
michael@0:     // onBrowserWindowLoad/onDownloadWindowLoad are going to set the active
michael@0:     // window, so don't do it here.
michael@0:   },
michael@0: 
michael@0:   /**
michael@0:    * Unregisters ourselves as a download progress listener.
michael@0:    */
michael@0:   _uninit: function DTPU_uninit() {
michael@0:     this._dm.removeListener(this);
michael@0:     this._os.removeObserver(this, "quit-application-granted");
michael@0:     this._activeTaskbarProgress = null;
michael@0:     this._initialized = false;
michael@0:   },
michael@0: 
michael@0:   /**
michael@0:    * This holds a reference to the taskbar progress for the window we're
michael@0:    * working with. This window would preferably be download window, but can be
michael@0:    * another window if it isn't open.
michael@0:    */
michael@0:   _activeTaskbarProgress: null,
michael@0: 
michael@0:   /// Whether the active window is the download window
michael@0:   _activeWindowIsDownloadWindow: false,
michael@0: 
michael@0:   /**
michael@0:    * Sets the active window, and whether it's the download window. This takes
michael@0:    * care of clearing out the previous active window's taskbar item, updating
michael@0:    * the taskbar, and setting an onunload listener.
michael@0:    *
michael@0:    * @param aWindow
michael@0:    *        The window to set as active.
michael@0:    * @param aIsDownloadWindow
michael@0:    *        Whether this window is a download window.
michael@0:    */
michael@0:   _setActiveWindow: function DTPU_setActiveWindow(aWindow, aIsDownloadWindow)
michael@0:   {
michael@0: #ifdef XP_WIN
michael@0:     // Clear out the taskbar for the old active window. (If there was no active
michael@0:     // window, this is a no-op.)
michael@0:     this._clearTaskbar();
michael@0: 
michael@0:     this._activeWindowIsDownloadWindow = aIsDownloadWindow;
michael@0:     if (aWindow) {
michael@0:       // Get the taskbar progress for this window
michael@0:       let docShell = aWindow.QueryInterface(Ci.nsIInterfaceRequestor).
michael@0:                        getInterface(Ci.nsIWebNavigation).
michael@0:                        QueryInterface(Ci.nsIDocShellTreeItem).treeOwner.
michael@0:                        QueryInterface(Ci.nsIInterfaceRequestor).
michael@0:                        getInterface(Ci.nsIXULWindow).docShell;
michael@0:       let taskbarProgress = this._taskbar.getTaskbarProgress(docShell);
michael@0:       this._activeTaskbarProgress = taskbarProgress;
michael@0: 
michael@0:       this._updateTaskbar();
michael@0:       // _onActiveWindowUnload is idempotent, so we don't need to check whether
michael@0:       // we've already set this before or not.
michael@0:       aWindow.addEventListener("unload", function () {
michael@0:         DownloadTaskbarProgressUpdater._onActiveWindowUnload(taskbarProgress);
michael@0:       }, false);
michael@0:     }
michael@0:     else {
michael@0:       this._activeTaskbarProgress = null;
michael@0:     }
michael@0: #endif
michael@0:   },
michael@0: 
michael@0:   /// Current state displayed on the active window's taskbar item
michael@0:   _taskbarState: null,
michael@0:   _totalSize: 0,
michael@0:   _totalTransferred: 0,
michael@0: 
michael@0:   _shouldSetState: function DTPU_shouldSetState()
michael@0:   {
michael@0: #ifdef XP_WIN
michael@0:     // If the active window is not the download manager window, set the state
michael@0:     // only if it is normal or indeterminate.
michael@0:     return this._activeWindowIsDownloadWindow ||
michael@0:            (this._taskbarState == Ci.nsITaskbarProgress.STATE_NORMAL ||
michael@0:             this._taskbarState == Ci.nsITaskbarProgress.STATE_INDETERMINATE);
michael@0: #else
michael@0:     return true;
michael@0: #endif
michael@0:   },
michael@0: 
michael@0:   /**
michael@0:    * Update the active window's taskbar indicator with the current state. There
michael@0:    * are two cases here:
michael@0:    * 1. If the active window is the download window, then we always update
michael@0:    *    the taskbar indicator.
michael@0:    * 2. If the active window isn't the download window, then we update only if
michael@0:    *    the status is normal or indeterminate. i.e. one or more downloads are
michael@0:    *    currently progressing or in scan mode. If we aren't, then we clear the
michael@0:    *    indicator.
michael@0:    */
michael@0:   _updateTaskbar: function DTPU_updateTaskbar()
michael@0:   {
michael@0:     if (!this._activeTaskbarProgress) {
michael@0:       return;
michael@0:     }
michael@0: 
michael@0:     if (this._shouldSetState()) {
michael@0:       this._activeTaskbarProgress.setProgressState(this._taskbarState,
michael@0:                                                    this._totalTransferred,
michael@0:                                                    this._totalSize);
michael@0:     }
michael@0:     // Clear any state otherwise
michael@0:     else {
michael@0:       this._clearTaskbar();
michael@0:     }
michael@0:   },
michael@0: 
michael@0:   /**
michael@0:    * Clear taskbar state. This is needed:
michael@0:    * - to transfer the indicator off a window before transferring it onto
michael@0:    *   another one
michael@0:    * - whenever we don't want to show it for a non-download window.
michael@0:    */
michael@0:   _clearTaskbar: function DTPU_clearTaskbar()
michael@0:   {
michael@0:     if (this._activeTaskbarProgress) {
michael@0:       this._activeTaskbarProgress.setProgressState(
michael@0:         Ci.nsITaskbarProgress.STATE_NO_PROGRESS
michael@0:       );
michael@0:     }
michael@0:   },
michael@0: 
michael@0:   /**
michael@0:    * Update this._taskbarState, this._totalSize and this._totalTransferred.
michael@0:    * This is called when the download manager is initialized or when the
michael@0:    * progress or state of a download changes.
michael@0:    * We compute the number of active and paused downloads, and the total size
michael@0:    * and total amount already transferred across whichever downloads we have
michael@0:    * the data for.
michael@0:    * - If there are no active downloads, then we don't want to show any
michael@0:    *   progress.
michael@0:    * - If the number of active downloads is equal to the number of paused
michael@0:    *   downloads, then we show a paused indicator if we know the size of at
michael@0:    *   least one download, and no indicator if we don't.
michael@0:    * - If the number of active downloads is more than the number of paused
michael@0:    *   downloads, then we show a "normal" indicator if we know the size of at
michael@0:    *   least one download, and an indeterminate indicator if we don't.
michael@0:    */
michael@0:   _updateStatus: function DTPU_updateStatus()
michael@0:   {
michael@0:     let numActive = this._dm.activeDownloadCount + this._dm.activePrivateDownloadCount;
michael@0:     let totalSize = 0, totalTransferred = 0;
michael@0: 
michael@0:     if (numActive == 0) {
michael@0:       this._taskbarState = Ci.nsITaskbarProgress.STATE_NO_PROGRESS;
michael@0:     }
michael@0:     else {
michael@0:       let numPaused = 0, numScanning = 0;
michael@0: 
michael@0:       // Enumerate all active downloads
michael@0:       [this._dm.activeDownloads, this._dm.activePrivateDownloads].forEach(function(downloads) {
michael@0:         while (downloads.hasMoreElements()) {
michael@0:           let download = downloads.getNext().QueryInterface(Ci.nsIDownload);
michael@0:           // Only set values if we actually know the download size
michael@0:           if (download.percentComplete != -1) {
michael@0:             totalSize += download.size;
michael@0:             totalTransferred += download.amountTransferred;
michael@0:           }
michael@0:           // We might need to display a paused state, so track this
michael@0:           if (download.state == this._dm.DOWNLOAD_PAUSED) {
michael@0:             numPaused++;
michael@0:           } else if (download.state == this._dm.DOWNLOAD_SCANNING) {
michael@0:             numScanning++;
michael@0:           }
michael@0:         }
michael@0:       }.bind(this));
michael@0: 
michael@0:       // If all downloads are paused, show the progress as paused, unless we
michael@0:       // don't have any information about sizes, in which case we don't
michael@0:       // display anything
michael@0:       if (numActive == numPaused) {
michael@0:         if (totalSize == 0) {
michael@0:           this._taskbarState = Ci.nsITaskbarProgress.STATE_NO_PROGRESS;
michael@0:           totalTransferred = 0;
michael@0:         }
michael@0:         else {
michael@0:           this._taskbarState = Ci.nsITaskbarProgress.STATE_PAUSED;
michael@0:         }
michael@0:       }
michael@0:       // If at least one download is not paused, and we don't have any
michael@0:       // information about download sizes, display an indeterminate indicator
michael@0:       else if (totalSize == 0 || numActive == numScanning) {
michael@0:         this._taskbarState = Ci.nsITaskbarProgress.STATE_INDETERMINATE;
michael@0:         totalSize = 0;
michael@0:         totalTransferred = 0;
michael@0:       }
michael@0:       // Otherwise display a normal progress bar
michael@0:       else {
michael@0:         this._taskbarState = Ci.nsITaskbarProgress.STATE_NORMAL;
michael@0:       }
michael@0:     }
michael@0: 
michael@0:     this._totalSize = totalSize;
michael@0:     this._totalTransferred = totalTransferred;
michael@0:   },
michael@0: 
michael@0:   /**
michael@0:    * Called when a window that at one point has been an active window is
michael@0:    * closed. If this window is currently the active window, we need to look for
michael@0:    * another window and make that our active window.
michael@0:    *
michael@0:    * This function is idempotent, so multiple calls for the same window are not
michael@0:    * a problem.
michael@0:    *
michael@0:    * @param aTaskbarProgress
michael@0:    *        The taskbar progress for the window that is being unloaded.
michael@0:    */
michael@0:   _onActiveWindowUnload: function DTPU_onActiveWindowUnload(aTaskbarProgress)
michael@0:   {
michael@0:     if (this._activeTaskbarProgress == aTaskbarProgress) {
michael@0:       let windowMediator = Cc["@mozilla.org/appshell/window-mediator;1"].
michael@0:                            getService(Ci.nsIWindowMediator);
michael@0:       let windows = windowMediator.getEnumerator(null);
michael@0:       let newActiveWindow = null;
michael@0:       if (windows.hasMoreElements()) {
michael@0:         newActiveWindow = windows.getNext().QueryInterface(Ci.nsIDOMWindow);
michael@0:       }
michael@0: 
michael@0:       // We aren't ever going to reach this point while the download manager is
michael@0:       // open, so it's safe to assume false for the second operand
michael@0:       this._setActiveWindow(newActiveWindow, false);
michael@0:     }
michael@0:   },
michael@0: 
michael@0:   //////////////////////////////////////////////////////////////////////////////
michael@0:   //// nsIDownloadProgressListener
michael@0: 
michael@0:   /**
michael@0:    * Update status if a download's progress has changed.
michael@0:    */
michael@0:   onProgressChange: function DTPU_onProgressChange()
michael@0:   {
michael@0:     this._updateStatus();
michael@0:     this._updateTaskbar();
michael@0:   },
michael@0: 
michael@0:   /**
michael@0:    * Update status if a download's state has changed.
michael@0:    */
michael@0:   onDownloadStateChange: function DTPU_onDownloadStateChange()
michael@0:   {
michael@0:     this._updateStatus();
michael@0:     this._updateTaskbar();
michael@0:   },
michael@0: 
michael@0:   onSecurityChange: function() { },
michael@0: 
michael@0:   onStateChange: function() { },
michael@0: 
michael@0:   observe: function DTPU_observe(aSubject, aTopic, aData) {
michael@0:     if (aTopic == "quit-application-granted") {
michael@0:       this._uninit();
michael@0:     }
michael@0:   }
michael@0: };