michael@0: /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
michael@0: /* vim: set ts=2 et sw=2 tw=80: */
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 file,
michael@0:  * You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: 
michael@0: /**
michael@0:  * Handles the Downloads panel user interface for each browser window.
michael@0:  *
michael@0:  * This file includes the following constructors and global objects:
michael@0:  *
michael@0:  * DownloadsPanel
michael@0:  * Main entry point for the downloads panel interface.
michael@0:  *
michael@0:  * DownloadsOverlayLoader
michael@0:  * Allows loading the downloads panel and the status indicator interfaces on
michael@0:  * demand, to improve startup performance.
michael@0:  *
michael@0:  * DownloadsView
michael@0:  * Builds and updates the downloads list widget, responding to changes in the
michael@0:  * download state and real-time data.  In addition, handles part of the user
michael@0:  * interaction events raised by the downloads list widget.
michael@0:  *
michael@0:  * DownloadsViewItem
michael@0:  * Builds and updates a single item in the downloads list widget, responding to
michael@0:  * changes in the download state and real-time data.
michael@0:  *
michael@0:  * DownloadsViewController
michael@0:  * Handles part of the user interaction events raised by the downloads list
michael@0:  * widget, in particular the "commands" that apply to multiple items, and
michael@0:  * dispatches the commands that apply to individual items.
michael@0:  *
michael@0:  * DownloadsViewItemController
michael@0:  * Handles all the user interaction events, in particular the "commands",
michael@0:  * related to a single item in the downloads list widgets.
michael@0:  */
michael@0: 
michael@0: /**
michael@0:  * A few words on focus and focusrings
michael@0:  *
michael@0:  * We do quite a few hacks in the Downloads Panel for focusrings. In fact, we
michael@0:  * basically suppress most if not all XUL-level focusrings, and style/draw
michael@0:  * them ourselves (using :focus instead of -moz-focusring). There are a few
michael@0:  * reasons for this:
michael@0:  *
michael@0:  * 1) Richlists on OSX don't have focusrings; instead, they are shown as
michael@0:  *    selected. This makes for some ambiguity when we have a focused/selected
michael@0:  *    item in the list, and the mouse is hovering a completed download (which
michael@0:  *    highlights).
michael@0:  * 2) Windows doesn't show focusrings until after the first time that tab is
michael@0:  *    pressed (and by then you're focusing the second item in the panel).
michael@0:  * 3) Richlistbox sets -moz-focusring even when we select it with a mouse.
michael@0:  *
michael@0:  * In general, the desired behaviour is to focus the first item after pressing
michael@0:  * tab/down, and show that focus with a ring. Then, if the mouse moves over
michael@0:  * the panel, to hide that focus ring; essentially resetting us to the state
michael@0:  * before pressing the key.
michael@0:  *
michael@0:  * We end up capturing the tab/down key events, and preventing their default
michael@0:  * behaviour. We then set a "keyfocus" attribute on the panel, which allows
michael@0:  * us to draw a ring around the currently focused element. If the panel is
michael@0:  * closed or the mouse moves over the panel, we remove the attribute.
michael@0:  */
michael@0: 
michael@0: "use strict";
michael@0: 
michael@0: ////////////////////////////////////////////////////////////////////////////////
michael@0: //// Globals
michael@0: 
michael@0: XPCOMUtils.defineLazyModuleGetter(this, "DownloadUtils",
michael@0:                                   "resource://gre/modules/DownloadUtils.jsm");
michael@0: XPCOMUtils.defineLazyModuleGetter(this, "DownloadsCommon",
michael@0:                                   "resource:///modules/DownloadsCommon.jsm");
michael@0: XPCOMUtils.defineLazyModuleGetter(this, "OS",
michael@0:                                   "resource://gre/modules/osfile.jsm");
michael@0: XPCOMUtils.defineLazyModuleGetter(this, "PrivateBrowsingUtils",
michael@0:                                   "resource://gre/modules/PrivateBrowsingUtils.jsm");
michael@0: XPCOMUtils.defineLazyModuleGetter(this, "PlacesUtils",
michael@0:                                   "resource://gre/modules/PlacesUtils.jsm");
michael@0: XPCOMUtils.defineLazyModuleGetter(this, "NetUtil",
michael@0:                                   "resource://gre/modules/NetUtil.jsm");
michael@0: 
michael@0: ////////////////////////////////////////////////////////////////////////////////
michael@0: //// DownloadsPanel
michael@0: 
michael@0: /**
michael@0:  * Main entry point for the downloads panel interface.
michael@0:  */
michael@0: const DownloadsPanel = {
michael@0:   //////////////////////////////////////////////////////////////////////////////
michael@0:   //// Initialization and termination
michael@0: 
michael@0:   /**
michael@0:    * Internal state of the downloads panel, based on one of the kState
michael@0:    * constants.  This is not the same state as the XUL panel element.
michael@0:    */
michael@0:   _state: 0,
michael@0: 
michael@0:   /** The panel is not linked to downloads data yet. */
michael@0:   get kStateUninitialized() 0,
michael@0:   /** This object is linked to data, but the panel is invisible. */
michael@0:   get kStateHidden() 1,
michael@0:   /** The panel will be shown as soon as possible. */
michael@0:   get kStateWaitingData() 2,
michael@0:   /** The panel is almost shown - we're just waiting to get a handle on the
michael@0:       anchor. */
michael@0:   get kStateWaitingAnchor() 3,
michael@0:   /** The panel is open. */
michael@0:   get kStateShown() 4,
michael@0: 
michael@0:   /**
michael@0:    * Location of the panel overlay.
michael@0:    */
michael@0:   get kDownloadsOverlay()
michael@0:       "chrome://browser/content/downloads/downloadsOverlay.xul",
michael@0: 
michael@0:   /**
michael@0:    * Starts loading the download data in background, without opening the panel.
michael@0:    * Use showPanel instead to load the data and open the panel at the same time.
michael@0:    *
michael@0:    * @param aCallback
michael@0:    *        Called when initialization is complete.
michael@0:    */
michael@0:   initialize: function DP_initialize(aCallback)
michael@0:   {
michael@0:     DownloadsCommon.log("Attempting to initialize DownloadsPanel for a window.");
michael@0:     if (this._state != this.kStateUninitialized) {
michael@0:       DownloadsCommon.log("DownloadsPanel is already initialized.");
michael@0:       DownloadsOverlayLoader.ensureOverlayLoaded(this.kDownloadsOverlay,
michael@0:                                                  aCallback);
michael@0:       return;
michael@0:     }
michael@0:     this._state = this.kStateHidden;
michael@0: 
michael@0:     window.addEventListener("unload", this.onWindowUnload, false);
michael@0: 
michael@0:     // Load and resume active downloads if required.  If there are downloads to
michael@0:     // be shown in the panel, they will be loaded asynchronously.
michael@0:     DownloadsCommon.initializeAllDataLinks();
michael@0: 
michael@0:     // Now that data loading has eventually started, load the required XUL
michael@0:     // elements and initialize our views.
michael@0:     DownloadsCommon.log("Ensuring DownloadsPanel overlay loaded.");
michael@0:     DownloadsOverlayLoader.ensureOverlayLoaded(this.kDownloadsOverlay,
michael@0:                                                function DP_I_callback() {
michael@0:       DownloadsViewController.initialize();
michael@0:       DownloadsCommon.log("Attaching DownloadsView...");
michael@0:       DownloadsCommon.getData(window).addView(DownloadsView);
michael@0:       DownloadsCommon.getSummary(window, DownloadsView.kItemCountLimit)
michael@0:                      .addView(DownloadsSummary);
michael@0:       DownloadsCommon.log("DownloadsView attached - the panel for this window",
michael@0:                           "should now see download items come in.");
michael@0:       DownloadsPanel._attachEventListeners();
michael@0:       DownloadsCommon.log("DownloadsPanel initialized.");
michael@0:       aCallback();
michael@0:     });
michael@0:   },
michael@0: 
michael@0:   /**
michael@0:    * Closes the downloads panel and frees the internal resources related to the
michael@0:    * downloads.  The downloads panel can be reopened later, even after this
michael@0:    * function has been called.
michael@0:    */
michael@0:   terminate: function DP_terminate()
michael@0:   {
michael@0:     DownloadsCommon.log("Attempting to terminate DownloadsPanel for a window.");
michael@0:     if (this._state == this.kStateUninitialized) {
michael@0:       DownloadsCommon.log("DownloadsPanel was never initialized. Nothing to do.");
michael@0:       return;
michael@0:     }
michael@0: 
michael@0:     window.removeEventListener("unload", this.onWindowUnload, false);
michael@0: 
michael@0:     // Ensure that the panel is closed before shutting down.
michael@0:     this.hidePanel();
michael@0: 
michael@0:     DownloadsViewController.terminate();
michael@0:     DownloadsCommon.getData(window).removeView(DownloadsView);
michael@0:     DownloadsCommon.getSummary(window, DownloadsView.kItemCountLimit)
michael@0:                    .removeView(DownloadsSummary);
michael@0:     this._unattachEventListeners();
michael@0: 
michael@0:     this._state = this.kStateUninitialized;
michael@0: 
michael@0:     DownloadsSummary.active = false;
michael@0:     DownloadsCommon.log("DownloadsPanel terminated.");
michael@0:   },
michael@0: 
michael@0:   //////////////////////////////////////////////////////////////////////////////
michael@0:   //// Panel interface
michael@0: 
michael@0:   /**
michael@0:    * Main panel element in the browser window, or null if the panel overlay
michael@0:    * hasn't been loaded yet.
michael@0:    */
michael@0:   get panel()
michael@0:   {
michael@0:     // If the downloads panel overlay hasn't loaded yet, just return null
michael@0:     // without reseting this.panel.
michael@0:     let downloadsPanel = document.getElementById("downloadsPanel");
michael@0:     if (!downloadsPanel)
michael@0:       return null;
michael@0: 
michael@0:     delete this.panel;
michael@0:     return this.panel = downloadsPanel;
michael@0:   },
michael@0: 
michael@0:   /**
michael@0:    * Starts opening the downloads panel interface, anchored to the downloads
michael@0:    * button of the browser window.  The list of downloads to display is
michael@0:    * initialized the first time this method is called, and the panel is shown
michael@0:    * only when data is ready.
michael@0:    */
michael@0:   showPanel: function DP_showPanel()
michael@0:   {
michael@0:     DownloadsCommon.log("Opening the downloads panel.");
michael@0: 
michael@0:     if (this.isPanelShowing) {
michael@0:       DownloadsCommon.log("Panel is already showing - focusing instead.");
michael@0:       this._focusPanel();
michael@0:       return;
michael@0:     }
michael@0: 
michael@0:     this.initialize(function DP_SP_callback() {
michael@0:       // Delay displaying the panel because this function will sometimes be
michael@0:       // called while another window is closing (like the window for selecting
michael@0:       // whether to save or open the file), and that would cause the panel to
michael@0:       // close immediately.
michael@0:       setTimeout(function () DownloadsPanel._openPopupIfDataReady(), 0);
michael@0:     }.bind(this));
michael@0: 
michael@0:     DownloadsCommon.log("Waiting for the downloads panel to appear.");
michael@0:     this._state = this.kStateWaitingData;
michael@0:   },
michael@0: 
michael@0:   /**
michael@0:    * Hides the downloads panel, if visible, but keeps the internal state so that
michael@0:    * the panel can be reopened quickly if required.
michael@0:    */
michael@0:   hidePanel: function DP_hidePanel()
michael@0:   {
michael@0:     DownloadsCommon.log("Closing the downloads panel.");
michael@0: 
michael@0:     if (!this.isPanelShowing) {
michael@0:       DownloadsCommon.log("Downloads panel is not showing - nothing to do.");
michael@0:       return;
michael@0:     }
michael@0: 
michael@0:     this.panel.hidePopup();
michael@0: 
michael@0:     // Ensure that we allow the panel to be reopened.  Note that, if the popup
michael@0:     // was open, then the onPopupHidden event handler has already updated the
michael@0:     // current state, otherwise we must update the state ourselves.
michael@0:     this._state = this.kStateHidden;
michael@0:     DownloadsCommon.log("Downloads panel is now closed.");
michael@0:   },
michael@0: 
michael@0:   /**
michael@0:    * Indicates whether the panel is shown or will be shown.
michael@0:    */
michael@0:   get isPanelShowing()
michael@0:   {
michael@0:     return this._state == this.kStateWaitingData ||
michael@0:            this._state == this.kStateWaitingAnchor ||
michael@0:            this._state == this.kStateShown;
michael@0:   },
michael@0: 
michael@0:   /**
michael@0:    * Returns whether the user has started keyboard navigation.
michael@0:    */
michael@0:   get keyFocusing()
michael@0:   {
michael@0:     return this.panel.hasAttribute("keyfocus");
michael@0:   },
michael@0: 
michael@0:   /**
michael@0:    * Set to true if the user has started keyboard navigation, and we should be
michael@0:    * showing focusrings in the panel. Also adds a mousemove event handler to
michael@0:    * the panel which disables keyFocusing.
michael@0:    */
michael@0:   set keyFocusing(aValue)
michael@0:   {
michael@0:     if (aValue) {
michael@0:       this.panel.setAttribute("keyfocus", "true");
michael@0:       this.panel.addEventListener("mousemove", this);
michael@0:     } else {
michael@0:       this.panel.removeAttribute("keyfocus");
michael@0:       this.panel.removeEventListener("mousemove", this);
michael@0:     }
michael@0:     return aValue;
michael@0:   },
michael@0: 
michael@0:   /**
michael@0:    * Handles the mousemove event for the panel, which disables focusring
michael@0:    * visualization.
michael@0:    */
michael@0:   handleEvent: function DP_handleEvent(aEvent)
michael@0:   {
michael@0:     if (aEvent.type == "mousemove") {
michael@0:       this.keyFocusing = false;
michael@0:     }
michael@0:   },
michael@0: 
michael@0:   //////////////////////////////////////////////////////////////////////////////
michael@0:   //// Callback functions from DownloadsView
michael@0: 
michael@0:   /**
michael@0:    * Called after data loading finished.
michael@0:    */
michael@0:   onViewLoadCompleted: function DP_onViewLoadCompleted()
michael@0:   {
michael@0:     this._openPopupIfDataReady();
michael@0:   },
michael@0: 
michael@0:   //////////////////////////////////////////////////////////////////////////////
michael@0:   //// User interface event functions
michael@0: 
michael@0:   onWindowUnload: function DP_onWindowUnload()
michael@0:   {
michael@0:     // This function is registered as an event listener, we can't use "this".
michael@0:     DownloadsPanel.terminate();
michael@0:   },
michael@0: 
michael@0:   onPopupShown: function DP_onPopupShown(aEvent)
michael@0:   {
michael@0:     // Ignore events raised by nested popups.
michael@0:     if (aEvent.target != aEvent.currentTarget) {
michael@0:       return;
michael@0:     }
michael@0: 
michael@0:     DownloadsCommon.log("Downloads panel has shown.");
michael@0:     this._state = this.kStateShown;
michael@0: 
michael@0:     // Since at most one popup is open at any given time, we can set globally.
michael@0:     DownloadsCommon.getIndicatorData(window).attentionSuppressed = true;
michael@0: 
michael@0:     // Ensure that the first item is selected when the panel is focused.
michael@0:     if (DownloadsView.richListBox.itemCount > 0 &&
michael@0:         DownloadsView.richListBox.selectedIndex == -1) {
michael@0:       DownloadsView.richListBox.selectedIndex = 0;
michael@0:     }
michael@0: 
michael@0:     this._focusPanel();
michael@0:   },
michael@0: 
michael@0:   onPopupHidden: function DP_onPopupHidden(aEvent)
michael@0:   {
michael@0:     // Ignore events raised by nested popups.
michael@0:     if (aEvent.target != aEvent.currentTarget) {
michael@0:       return;
michael@0:     }
michael@0: 
michael@0:     DownloadsCommon.log("Downloads panel has hidden.");
michael@0: 
michael@0:     // Removes the keyfocus attribute so that we stop handling keyboard
michael@0:     // navigation.
michael@0:     this.keyFocusing = false;
michael@0: 
michael@0:     // Since at most one popup is open at any given time, we can set globally.
michael@0:     DownloadsCommon.getIndicatorData(window).attentionSuppressed = false;
michael@0: 
michael@0:     // Allow the anchor to be hidden.
michael@0:     DownloadsButton.releaseAnchor();
michael@0: 
michael@0:     // Allow the panel to be reopened.
michael@0:     this._state = this.kStateHidden;
michael@0:   },
michael@0: 
michael@0:   //////////////////////////////////////////////////////////////////////////////
michael@0:   //// Related operations
michael@0: 
michael@0:   /**
michael@0:    * Shows or focuses the user interface dedicated to downloads history.
michael@0:    */
michael@0:   showDownloadsHistory: function DP_showDownloadsHistory()
michael@0:   {
michael@0:     DownloadsCommon.log("Showing download history.");
michael@0:     // Hide the panel before showing another window, otherwise focus will return
michael@0:     // to the browser window when the panel closes automatically.
michael@0:     this.hidePanel();
michael@0: 
michael@0:     BrowserDownloadsUI();
michael@0:   },
michael@0: 
michael@0:   //////////////////////////////////////////////////////////////////////////////
michael@0:   //// Internal functions
michael@0: 
michael@0:   /**
michael@0:    * Attach event listeners to a panel element. These listeners should be
michael@0:    * removed in _unattachEventListeners. This is called automatically after the
michael@0:    * panel has successfully loaded.
michael@0:    */
michael@0:   _attachEventListeners: function DP__attachEventListeners()
michael@0:   {
michael@0:     // Handle keydown to support accel-V.
michael@0:     this.panel.addEventListener("keydown", this._onKeyDown.bind(this), false);
michael@0:     // Handle keypress to be able to preventDefault() events before they reach
michael@0:     // the richlistbox, for keyboard navigation.
michael@0:     this.panel.addEventListener("keypress", this._onKeyPress.bind(this), false);
michael@0:   },
michael@0: 
michael@0:   /**
michael@0:    * Unattach event listeners that were added in _attachEventListeners. This
michael@0:    * is called automatically on panel termination.
michael@0:    */
michael@0:   _unattachEventListeners: function DP__unattachEventListeners()
michael@0:   {
michael@0:     this.panel.removeEventListener("keydown", this._onKeyDown.bind(this),
michael@0:                                    false);
michael@0:     this.panel.removeEventListener("keypress", this._onKeyPress.bind(this),
michael@0:                                    false);
michael@0:   },
michael@0: 
michael@0:   _onKeyPress: function DP__onKeyPress(aEvent)
michael@0:   {
michael@0:     // Handle unmodified keys only.
michael@0:     if (aEvent.altKey || aEvent.ctrlKey || aEvent.shiftKey || aEvent.metaKey) {
michael@0:       return;
michael@0:     }
michael@0: 
michael@0:     let richListBox = DownloadsView.richListBox;
michael@0: 
michael@0:     // If the user has pressed the tab, up, or down cursor key, start keyboard
michael@0:     // navigation, thus enabling focusrings in the panel.  Keyboard navigation
michael@0:     // is automatically disabled if the user moves the mouse on the panel, or
michael@0:     // if the panel is closed.
michael@0:     if ((aEvent.keyCode == Ci.nsIDOMKeyEvent.DOM_VK_TAB ||
michael@0:         aEvent.keyCode == Ci.nsIDOMKeyEvent.DOM_VK_UP ||
michael@0:         aEvent.keyCode == Ci.nsIDOMKeyEvent.DOM_VK_DOWN) &&
michael@0:         !this.keyFocusing) {
michael@0:       this.keyFocusing = true;
michael@0:       // Ensure there's a selection, we will show the focus ring around it and
michael@0:       // prevent the richlistbox from changing the selection.
michael@0:       if (DownloadsView.richListBox.selectedIndex == -1)
michael@0:         DownloadsView.richListBox.selectedIndex = 0;
michael@0:       aEvent.preventDefault();
michael@0:       return;
michael@0:     }
michael@0: 
michael@0:     if (aEvent.keyCode == Ci.nsIDOMKeyEvent.DOM_VK_DOWN) {
michael@0:       // If the last element in the list is selected, or the footer is already
michael@0:       // focused, focus the footer.
michael@0:       if (richListBox.selectedItem === richListBox.lastChild ||
michael@0:           document.activeElement.parentNode.id === "downloadsFooter") {
michael@0:         DownloadsFooter.focus();
michael@0:         aEvent.preventDefault();
michael@0:         return;
michael@0:       }
michael@0:     }
michael@0: 
michael@0:     // Pass keypress events to the richlistbox view when it's focused.
michael@0:     if (document.activeElement === richListBox) {
michael@0:       DownloadsView.onDownloadKeyPress(aEvent);
michael@0:     }
michael@0:   },
michael@0: 
michael@0:   /**
michael@0:    * Keydown listener that listens for the keys to start key focusing, as well
michael@0:    * as the the accel-V "paste" event, which initiates a file download if the
michael@0:    * pasted item can be resolved to a URI.
michael@0:    */
michael@0:   _onKeyDown: function DP__onKeyDown(aEvent)
michael@0:   {
michael@0:     // If the footer is focused and the downloads list has at least 1 element
michael@0:     // in it, focus the last element in the list when going up.
michael@0:     if (aEvent.keyCode == Ci.nsIDOMKeyEvent.DOM_VK_UP &&
michael@0:         document.activeElement.parentNode.id === "downloadsFooter" &&
michael@0:         DownloadsView.richListBox.firstChild) {
michael@0:       DownloadsView.richListBox.focus();
michael@0:       DownloadsView.richListBox.selectedItem = DownloadsView.richListBox.lastChild;
michael@0:       aEvent.preventDefault();
michael@0:       return;
michael@0:     }
michael@0: 
michael@0:     let pasting = aEvent.keyCode == Ci.nsIDOMKeyEvent.DOM_VK_V &&
michael@0: #ifdef XP_MACOSX
michael@0:                   aEvent.metaKey;
michael@0: #else
michael@0:                   aEvent.ctrlKey;
michael@0: #endif
michael@0: 
michael@0:     if (!pasting) {
michael@0:       return;
michael@0:     }
michael@0: 
michael@0:     DownloadsCommon.log("Received a paste event.");
michael@0: 
michael@0:     let trans = Cc["@mozilla.org/widget/transferable;1"]
michael@0:                   .createInstance(Ci.nsITransferable);
michael@0:     trans.init(null);
michael@0:     let flavors = ["text/x-moz-url", "text/unicode"];
michael@0:     flavors.forEach(trans.addDataFlavor);
michael@0:     Services.clipboard.getData(trans, Services.clipboard.kGlobalClipboard);
michael@0:     // Getting the data or creating the nsIURI might fail
michael@0:     try {
michael@0:       let data = {};
michael@0:       trans.getAnyTransferData({}, data, {});
michael@0:       let [url, name] = data.value
michael@0:                             .QueryInterface(Ci.nsISupportsString)
michael@0:                             .data
michael@0:                             .split("\n");
michael@0:       if (!url) {
michael@0:         return;
michael@0:       }
michael@0: 
michael@0:       let uri = NetUtil.newURI(url);
michael@0:       DownloadsCommon.log("Pasted URL seems valid. Starting download.");
michael@0:       DownloadURL(uri.spec, name, document);
michael@0:     } catch (ex) {}
michael@0:   },
michael@0: 
michael@0:   /**
michael@0:    * Move focus to the main element in the downloads panel, unless another
michael@0:    * element in the panel is already focused.
michael@0:    */
michael@0:   _focusPanel: function DP_focusPanel()
michael@0:   {
michael@0:     // We may be invoked while the panel is still waiting to be shown.
michael@0:     if (this._state != this.kStateShown) {
michael@0:       return;
michael@0:     }
michael@0: 
michael@0:     let element = document.commandDispatcher.focusedElement;
michael@0:     while (element && element != this.panel) {
michael@0:       element = element.parentNode;
michael@0:     }
michael@0:     if (!element) {
michael@0:       if (DownloadsView.richListBox.itemCount > 0) {
michael@0:         DownloadsView.richListBox.focus();
michael@0:       } else {
michael@0:         DownloadsFooter.focus();
michael@0:       }
michael@0:     }
michael@0:   },
michael@0: 
michael@0:   /**
michael@0:    * Opens the downloads panel when data is ready to be displayed.
michael@0:    */
michael@0:   _openPopupIfDataReady: function DP_openPopupIfDataReady()
michael@0:   {
michael@0:     // We don't want to open the popup if we already displayed it, or if we are
michael@0:     // still loading data.
michael@0:     if (this._state != this.kStateWaitingData || DownloadsView.loading) {
michael@0:       return;
michael@0:     }
michael@0: 
michael@0:     this._state = this.kStateWaitingAnchor;
michael@0: 
michael@0:     // Ensure the anchor is visible.  If that is not possible, show the panel
michael@0:     // anchored to the top area of the window, near the default anchor position.
michael@0:     DownloadsButton.getAnchor(function DP_OPIDR_callback(aAnchor) {
michael@0:       // If somehow we've switched states already (by getting a panel hiding
michael@0:       // event before an overlay is loaded, for example), bail out.
michael@0:       if (this._state != this.kStateWaitingAnchor)
michael@0:         return;
michael@0: 
michael@0:       // At this point, if the window is minimized, opening the panel could fail
michael@0:       // without any notification, and there would be no way to either open or
michael@0:       // close the panel anymore.  To prevent this, check if the window is
michael@0:       // minimized and in that case force the panel to the closed state.
michael@0:       if (window.windowState == Ci.nsIDOMChromeWindow.STATE_MINIMIZED) {
michael@0:         DownloadsButton.releaseAnchor();
michael@0:         this._state = this.kStateHidden;
michael@0:         return;
michael@0:       }
michael@0: 
michael@0:       // When the panel is opened, we check if the target files of visible items
michael@0:       // still exist, and update the allowed items interactions accordingly.  We
michael@0:       // do these checks on a background thread, and don't prevent the panel to
michael@0:       // be displayed while these checks are being performed.
michael@0:       for each (let viewItem in DownloadsView._viewItems) {
michael@0:         viewItem.verifyTargetExists();
michael@0:       }
michael@0: 
michael@0:       if (aAnchor) {
michael@0:         DownloadsCommon.log("Opening downloads panel popup.");
michael@0:         this.panel.openPopup(aAnchor, "bottomcenter topright", 0, 0, false,
michael@0:                              null);
michael@0:       } else {
michael@0:         DownloadsCommon.error("We can't find the anchor! Failure case - opening",
michael@0:                               "downloads panel on TabsToolbar. We should never",
michael@0:                               "get here!");
michael@0:         Components.utils.reportError(
michael@0:           "Downloads button cannot be found");
michael@0:       }
michael@0:     }.bind(this));
michael@0:   }
michael@0: };
michael@0: 
michael@0: ////////////////////////////////////////////////////////////////////////////////
michael@0: //// DownloadsOverlayLoader
michael@0: 
michael@0: /**
michael@0:  * Allows loading the downloads panel and the status indicator interfaces on
michael@0:  * demand, to improve startup performance.
michael@0:  */
michael@0: const DownloadsOverlayLoader = {
michael@0:   /**
michael@0:    * We cannot load two overlays at the same time, thus we use a queue of
michael@0:    * pending load requests.
michael@0:    */
michael@0:   _loadRequests: [],
michael@0: 
michael@0:   /**
michael@0:    * True while we are waiting for an overlay to be loaded.
michael@0:    */
michael@0:   _overlayLoading: false,
michael@0: 
michael@0:   /**
michael@0:    * This object has a key for each overlay URI that is already loaded.
michael@0:    */
michael@0:   _loadedOverlays: {},
michael@0: 
michael@0:   /**
michael@0:    * Loads the specified overlay and invokes the given callback when finished.
michael@0:    *
michael@0:    * @param aOverlay
michael@0:    *        String containing the URI of the overlay to load in the current
michael@0:    *        window.  If this overlay has already been loaded using this
michael@0:    *        function, then the overlay is not loaded again.
michael@0:    * @param aCallback
michael@0:    *        Invoked when loading is completed.  If the overlay is already
michael@0:    *        loaded, the function is called immediately.
michael@0:    */
michael@0:   ensureOverlayLoaded: function DOL_ensureOverlayLoaded(aOverlay, aCallback)
michael@0:   {
michael@0:     // The overlay is already loaded, invoke the callback immediately.
michael@0:     if (aOverlay in this._loadedOverlays) {
michael@0:       aCallback();
michael@0:       return;
michael@0:     }
michael@0: 
michael@0:     // The callback will be invoked when loading is finished.
michael@0:     this._loadRequests.push({ overlay: aOverlay, callback: aCallback });
michael@0:     if (this._overlayLoading) {
michael@0:       return;
michael@0:     }
michael@0: 
michael@0:     function DOL_EOL_loadCallback() {
michael@0:       this._overlayLoading = false;
michael@0:       this._loadedOverlays[aOverlay] = true;
michael@0: 
michael@0:       this.processPendingRequests();
michael@0:     }
michael@0: 
michael@0:     this._overlayLoading = true;
michael@0:     DownloadsCommon.log("Loading overlay ", aOverlay);
michael@0:     document.loadOverlay(aOverlay, DOL_EOL_loadCallback.bind(this));
michael@0:   },
michael@0: 
michael@0:   /**
michael@0:    * Re-processes all the currently pending requests, invoking the callbacks
michael@0:    * and/or loading more overlays as needed.  In most cases, there will be a
michael@0:    * single request for one overlay, that will be processed immediately.
michael@0:    */
michael@0:   processPendingRequests: function DOL_processPendingRequests()
michael@0:   {
michael@0:     // Re-process all the currently pending requests, yet allow more requests
michael@0:     // to be appended at the end of the array if we're not ready for them.
michael@0:     let currentLength = this._loadRequests.length;
michael@0:     for (let i = 0; i < currentLength; i++) {
michael@0:       let request = this._loadRequests.shift();
michael@0: 
michael@0:       // We must call ensureOverlayLoaded again for each request, to check if
michael@0:       // the associated callback can be invoked now, or if we must still wait
michael@0:       // for the associated overlay to load.
michael@0:       this.ensureOverlayLoaded(request.overlay, request.callback);
michael@0:     }
michael@0:   }
michael@0: };
michael@0: 
michael@0: ////////////////////////////////////////////////////////////////////////////////
michael@0: //// DownloadsView
michael@0: 
michael@0: /**
michael@0:  * Builds and updates the downloads list widget, responding to changes in the
michael@0:  * download state and real-time data.  In addition, handles part of the user
michael@0:  * interaction events raised by the downloads list widget.
michael@0:  */
michael@0: const DownloadsView = {
michael@0:   //////////////////////////////////////////////////////////////////////////////
michael@0:   //// Functions handling download items in the list
michael@0: 
michael@0:   /**
michael@0:    * Maximum number of items shown by the list at any given time.
michael@0:    */
michael@0:   kItemCountLimit: 3,
michael@0: 
michael@0:   /**
michael@0:    * Indicates whether we are still loading downloads data asynchronously.
michael@0:    */
michael@0:   loading: false,
michael@0: 
michael@0:   /**
michael@0:    * Ordered array of all DownloadsDataItem objects.  We need to keep this array
michael@0:    * because only a limited number of items are shown at once, and if an item
michael@0:    * that is currently visible is removed from the list, we might need to take
michael@0:    * another item from the array and make it appear at the bottom.
michael@0:    */
michael@0:   _dataItems: [],
michael@0: 
michael@0:   /**
michael@0:    * Object containing the available DownloadsViewItem objects, indexed by their
michael@0:    * numeric download identifier.  There is a limited number of view items in
michael@0:    * the panel at any given time.
michael@0:    */
michael@0:   _viewItems: {},
michael@0: 
michael@0:   /**
michael@0:    * Called when the number of items in the list changes.
michael@0:    */
michael@0:   _itemCountChanged: function DV_itemCountChanged()
michael@0:   {
michael@0:     DownloadsCommon.log("The downloads item count has changed - we are tracking",
michael@0:                         this._dataItems.length, "downloads in total.");
michael@0:     let count = this._dataItems.length;
michael@0:     let hiddenCount = count - this.kItemCountLimit;
michael@0: 
michael@0:     if (count > 0) {
michael@0:       DownloadsCommon.log("Setting the panel's hasdownloads attribute to true.");
michael@0:       DownloadsPanel.panel.setAttribute("hasdownloads", "true");
michael@0:     } else {
michael@0:       DownloadsCommon.log("Removing the panel's hasdownloads attribute.");
michael@0:       DownloadsPanel.panel.removeAttribute("hasdownloads");
michael@0:     }
michael@0: 
michael@0:     // If we've got some hidden downloads, we should activate the
michael@0:     // DownloadsSummary. The DownloadsSummary will determine whether or not
michael@0:     // it's appropriate to actually display the summary.
michael@0:     DownloadsSummary.active = hiddenCount > 0;
michael@0:   },
michael@0: 
michael@0:   /**
michael@0:    * Element corresponding to the list of downloads.
michael@0:    */
michael@0:   get richListBox()
michael@0:   {
michael@0:     delete this.richListBox;
michael@0:     return this.richListBox = document.getElementById("downloadsListBox");
michael@0:   },
michael@0: 
michael@0:   /**
michael@0:    * Element corresponding to the button for showing more downloads.
michael@0:    */
michael@0:   get downloadsHistory()
michael@0:   {
michael@0:     delete this.downloadsHistory;
michael@0:     return this.downloadsHistory = document.getElementById("downloadsHistory");
michael@0:   },
michael@0: 
michael@0:   //////////////////////////////////////////////////////////////////////////////
michael@0:   //// Callback functions from DownloadsData
michael@0: 
michael@0:   /**
michael@0:    * Called before multiple downloads are about to be loaded.
michael@0:    */
michael@0:   onDataLoadStarting: function DV_onDataLoadStarting()
michael@0:   {
michael@0:     DownloadsCommon.log("onDataLoadStarting called for DownloadsView.");
michael@0:     this.loading = true;
michael@0:   },
michael@0: 
michael@0:   /**
michael@0:    * Called after data loading finished.
michael@0:    */
michael@0:   onDataLoadCompleted: function DV_onDataLoadCompleted()
michael@0:   {
michael@0:     DownloadsCommon.log("onDataLoadCompleted called for DownloadsView.");
michael@0: 
michael@0:     this.loading = false;
michael@0: 
michael@0:     // We suppressed item count change notifications during the batch load, at
michael@0:     // this point we should just call the function once.
michael@0:     this._itemCountChanged();
michael@0: 
michael@0:     // Notify the panel that all the initially available downloads have been
michael@0:     // loaded.  This ensures that the interface is visible, if still required.
michael@0:     DownloadsPanel.onViewLoadCompleted();
michael@0:   },
michael@0: 
michael@0:   /**
michael@0:    * Called when a new download data item is available, either during the
michael@0:    * asynchronous data load or when a new download is started.
michael@0:    *
michael@0:    * @param aDataItem
michael@0:    *        DownloadsDataItem object that was just added.
michael@0:    * @param aNewest
michael@0:    *        When true, indicates that this item is the most recent and should be
michael@0:    *        added in the topmost position.  This happens when a new download is
michael@0:    *        started.  When false, indicates that the item is the least recent
michael@0:    *        and should be appended.  The latter generally happens during the
michael@0:    *        asynchronous data load.
michael@0:    */
michael@0:   onDataItemAdded: function DV_onDataItemAdded(aDataItem, aNewest)
michael@0:   {
michael@0:     DownloadsCommon.log("A new download data item was added - aNewest =",
michael@0:                         aNewest);
michael@0: 
michael@0:     if (aNewest) {
michael@0:       this._dataItems.unshift(aDataItem);
michael@0:     } else {
michael@0:       this._dataItems.push(aDataItem);
michael@0:     }
michael@0: 
michael@0:     let itemsNowOverflow = this._dataItems.length > this.kItemCountLimit;
michael@0:     if (aNewest || !itemsNowOverflow) {
michael@0:       // The newly added item is visible in the panel and we must add the
michael@0:       // corresponding element.  This is either because it is the first item, or
michael@0:       // because it was added at the bottom but the list still doesn't overflow.
michael@0:       this._addViewItem(aDataItem, aNewest);
michael@0:     }
michael@0:     if (aNewest && itemsNowOverflow) {
michael@0:       // If the list overflows, remove the last item from the panel to make room
michael@0:       // for the new one that we just added at the top.
michael@0:       this._removeViewItem(this._dataItems[this.kItemCountLimit]);
michael@0:     }
michael@0: 
michael@0:     // For better performance during batch loads, don't update the count for
michael@0:     // every item, because the interface won't be visible until load finishes.
michael@0:     if (!this.loading) {
michael@0:       this._itemCountChanged();
michael@0:     }
michael@0:   },
michael@0: 
michael@0:   /**
michael@0:    * Called when a data item is removed.  Ensures that the widget associated
michael@0:    * with the view item is removed from the user interface.
michael@0:    *
michael@0:    * @param aDataItem
michael@0:    *        DownloadsDataItem object that is being removed.
michael@0:    */
michael@0:   onDataItemRemoved: function DV_onDataItemRemoved(aDataItem)
michael@0:   {
michael@0:     DownloadsCommon.log("A download data item was removed.");
michael@0: 
michael@0:     let itemIndex = this._dataItems.indexOf(aDataItem);
michael@0:     this._dataItems.splice(itemIndex, 1);
michael@0: 
michael@0:     if (itemIndex < this.kItemCountLimit) {
michael@0:       // The item to remove is visible in the panel.
michael@0:       this._removeViewItem(aDataItem);
michael@0:       if (this._dataItems.length >= this.kItemCountLimit) {
michael@0:         // Reinsert the next item into the panel.
michael@0:         this._addViewItem(this._dataItems[this.kItemCountLimit - 1], false);
michael@0:       }
michael@0:     }
michael@0: 
michael@0:     this._itemCountChanged();
michael@0:   },
michael@0: 
michael@0:   /**
michael@0:    * Returns the view item associated with the provided data item for this view.
michael@0:    *
michael@0:    * @param aDataItem
michael@0:    *        DownloadsDataItem object for which the view item is requested.
michael@0:    *
michael@0:    * @return Object that can be used to notify item status events.
michael@0:    */
michael@0:   getViewItem: function DV_getViewItem(aDataItem)
michael@0:   {
michael@0:     // If the item is visible, just return it, otherwise return a mock object
michael@0:     // that doesn't react to notifications.
michael@0:     if (aDataItem.downloadGuid in this._viewItems) {
michael@0:       return this._viewItems[aDataItem.downloadGuid];
michael@0:     }
michael@0:     return this._invisibleViewItem;
michael@0:   },
michael@0: 
michael@0:   /**
michael@0:    * Mock DownloadsDataItem object that doesn't react to notifications.
michael@0:    */
michael@0:   _invisibleViewItem: Object.freeze({
michael@0:     onStateChange: function () { },
michael@0:     onProgressChange: function () { }
michael@0:   }),
michael@0: 
michael@0:   /**
michael@0:    * Creates a new view item associated with the specified data item, and adds
michael@0:    * it to the top or the bottom of the list.
michael@0:    */
michael@0:   _addViewItem: function DV_addViewItem(aDataItem, aNewest)
michael@0:   {
michael@0:     DownloadsCommon.log("Adding a new DownloadsViewItem to the downloads list.",
michael@0:                         "aNewest =", aNewest);
michael@0: 
michael@0:     let element = document.createElement("richlistitem");
michael@0:     let viewItem = new DownloadsViewItem(aDataItem, element);
michael@0:     this._viewItems[aDataItem.downloadGuid] = viewItem;
michael@0:     if (aNewest) {
michael@0:       this.richListBox.insertBefore(element, this.richListBox.firstChild);
michael@0:     } else {
michael@0:       this.richListBox.appendChild(element);
michael@0:     }
michael@0:   },
michael@0: 
michael@0:   /**
michael@0:    * Removes the view item associated with the specified data item.
michael@0:    */
michael@0:   _removeViewItem: function DV_removeViewItem(aDataItem)
michael@0:   {
michael@0:     DownloadsCommon.log("Removing a DownloadsViewItem from the downloads list.");
michael@0:     let element = this.getViewItem(aDataItem)._element;
michael@0:     let previousSelectedIndex = this.richListBox.selectedIndex;
michael@0:     this.richListBox.removeChild(element);
michael@0:     if (previousSelectedIndex != -1) {
michael@0:       this.richListBox.selectedIndex = Math.min(previousSelectedIndex,
michael@0:                                                 this.richListBox.itemCount - 1);
michael@0:     }
michael@0:     delete this._viewItems[aDataItem.downloadGuid];
michael@0:   },
michael@0: 
michael@0:   //////////////////////////////////////////////////////////////////////////////
michael@0:   //// User interface event functions
michael@0: 
michael@0:   /**
michael@0:    * Helper function to do commands on a specific download item.
michael@0:    *
michael@0:    * @param aEvent
michael@0:    *        Event object for the event being handled.  If the event target is
michael@0:    *        not a richlistitem that represents a download, this function will
michael@0:    *        walk up the parent nodes until it finds a DOM node that is.
michael@0:    * @param aCommand
michael@0:    *        The command to be performed.
michael@0:    */
michael@0:   onDownloadCommand: function DV_onDownloadCommand(aEvent, aCommand)
michael@0:   {
michael@0:     let target = aEvent.target;
michael@0:     while (target.nodeName != "richlistitem") {
michael@0:       target = target.parentNode;
michael@0:     }
michael@0:     new DownloadsViewItemController(target).doCommand(aCommand);
michael@0:   },
michael@0: 
michael@0:   onDownloadClick: function DV_onDownloadClick(aEvent)
michael@0:   {
michael@0:     // Handle primary clicks only, and exclude the action button.
michael@0:     if (aEvent.button == 0 &&
michael@0:         !aEvent.originalTarget.hasAttribute("oncommand")) {
michael@0:       goDoCommand("downloadsCmd_open");
michael@0:     }
michael@0:   },
michael@0: 
michael@0:   /**
michael@0:    * Handles keypress events on a download item.
michael@0:    */
michael@0:   onDownloadKeyPress: function DV_onDownloadKeyPress(aEvent)
michael@0:   {
michael@0:     // Pressing the key on buttons should not invoke the action because the
michael@0:     // event has already been handled by the button itself.
michael@0:     if (aEvent.originalTarget.hasAttribute("command") ||
michael@0:         aEvent.originalTarget.hasAttribute("oncommand")) {
michael@0:       return;
michael@0:     }
michael@0: 
michael@0:     if (aEvent.charCode == " ".charCodeAt(0)) {
michael@0:       goDoCommand("downloadsCmd_pauseResume");
michael@0:       return;
michael@0:     }
michael@0: 
michael@0:     if (aEvent.keyCode == KeyEvent.DOM_VK_RETURN) {
michael@0:       goDoCommand("downloadsCmd_doDefault");
michael@0:     }
michael@0:   },
michael@0: 
michael@0: 
michael@0:   /**
michael@0:    * Mouse listeners to handle selection on hover.
michael@0:    */
michael@0:   onDownloadMouseOver: function DV_onDownloadMouseOver(aEvent)
michael@0:   {
michael@0:     if (aEvent.originalTarget.parentNode == this.richListBox)
michael@0:       this.richListBox.selectedItem = aEvent.originalTarget;
michael@0:   },
michael@0:   onDownloadMouseOut: function DV_onDownloadMouseOut(aEvent)
michael@0:   {
michael@0:     if (aEvent.originalTarget.parentNode == this.richListBox) {
michael@0:       // If the destination element is outside of the richlistitem, clear the
michael@0:       // selection.
michael@0:       let element = aEvent.relatedTarget;
michael@0:       while (element && element != aEvent.originalTarget) {
michael@0:         element = element.parentNode;
michael@0:       }
michael@0:       if (!element)
michael@0:         this.richListBox.selectedIndex = -1;
michael@0:     }
michael@0:   },
michael@0: 
michael@0:   onDownloadContextMenu: function DV_onDownloadContextMenu(aEvent)
michael@0:   {
michael@0:     let element = this.richListBox.selectedItem;
michael@0:     if (!element) {
michael@0:       return;
michael@0:     }
michael@0: 
michael@0:     DownloadsViewController.updateCommands();
michael@0: 
michael@0:     // Set the state attribute so that only the appropriate items are displayed.
michael@0:     let contextMenu = document.getElementById("downloadsContextMenu");
michael@0:     contextMenu.setAttribute("state", element.getAttribute("state"));
michael@0:   },
michael@0: 
michael@0:   onDownloadDragStart: function DV_onDownloadDragStart(aEvent)
michael@0:   {
michael@0:     let element = this.richListBox.selectedItem;
michael@0:     if (!element) {
michael@0:       return;
michael@0:     }
michael@0: 
michael@0:     let controller = new DownloadsViewItemController(element);
michael@0:     let localFile = controller.dataItem.localFile;
michael@0:     if (!localFile.exists()) {
michael@0:       return;
michael@0:     }
michael@0: 
michael@0:     let dataTransfer = aEvent.dataTransfer;
michael@0:     dataTransfer.mozSetDataAt("application/x-moz-file", localFile, 0);
michael@0:     dataTransfer.effectAllowed = "copyMove";
michael@0:     var url = Services.io.newFileURI(localFile).spec;
michael@0:     dataTransfer.setData("text/uri-list", url);
michael@0:     dataTransfer.setData("text/plain", url);
michael@0:     dataTransfer.addElement(element);
michael@0: 
michael@0:     aEvent.stopPropagation();
michael@0:   }
michael@0: }
michael@0: 
michael@0: ////////////////////////////////////////////////////////////////////////////////
michael@0: //// DownloadsViewItem
michael@0: 
michael@0: /**
michael@0:  * Builds and updates a single item in the downloads list widget, responding to
michael@0:  * changes in the download state and real-time data.
michael@0:  *
michael@0:  * @param aDataItem
michael@0:  *        DownloadsDataItem to be associated with the view item.
michael@0:  * @param aElement
michael@0:  *        XUL element corresponding to the single download item in the view.
michael@0:  */
michael@0: function DownloadsViewItem(aDataItem, aElement)
michael@0: {
michael@0:   this._element = aElement;
michael@0:   this.dataItem = aDataItem;
michael@0: 
michael@0:   this.lastEstimatedSecondsLeft = Infinity;
michael@0: 
michael@0:   // Set the URI that represents the correct icon for the target file.  As soon
michael@0:   // as bug 239948 comment 12 is handled, the "file" property will be always a
michael@0:   // file URL rather than a file name.  At that point we should remove the "//"
michael@0:   // (double slash) from the icon URI specification (see test_moz_icon_uri.js).
michael@0:   this.image = "moz-icon://" + this.dataItem.file + "?size=32";
michael@0: 
michael@0:   let attributes = {
michael@0:     "type": "download",
michael@0:     "class": "download-state",
michael@0:     "id": "downloadsItem_" + this.dataItem.downloadGuid,
michael@0:     "downloadGuid": this.dataItem.downloadGuid,
michael@0:     "state": this.dataItem.state,
michael@0:     "progress": this.dataItem.inProgress ? this.dataItem.percentComplete : 100,
michael@0:     "target": this.dataItem.target,
michael@0:     "image": this.image
michael@0:   };
michael@0: 
michael@0:   for (let attributeName in attributes) {
michael@0:     this._element.setAttribute(attributeName, attributes[attributeName]);
michael@0:   }
michael@0: 
michael@0:   // Initialize more complex attributes.
michael@0:   this._updateProgress();
michael@0:   this._updateStatusLine();
michael@0:   this.verifyTargetExists();
michael@0: }
michael@0: 
michael@0: DownloadsViewItem.prototype = {
michael@0:   /**
michael@0:    * The DownloadDataItem associated with this view item.
michael@0:    */
michael@0:   dataItem: null,
michael@0: 
michael@0:   /**
michael@0:    * The XUL element corresponding to the associated richlistbox item.
michael@0:    */
michael@0:   _element: null,
michael@0: 
michael@0:   /**
michael@0:    * The inner XUL element for the progress bar, or null if not available.
michael@0:    */
michael@0:   _progressElement: null,
michael@0: 
michael@0:   //////////////////////////////////////////////////////////////////////////////
michael@0:   //// Callback functions from DownloadsData
michael@0: 
michael@0:   /**
michael@0:    * Called when the download state might have changed.  Sometimes the state of
michael@0:    * the download might be the same as before, if the data layer received
michael@0:    * multiple events for the same download.
michael@0:    */
michael@0:   onStateChange: function DVI_onStateChange(aOldState)
michael@0:   {
michael@0:     // If a download just finished successfully, it means that the target file
michael@0:     // now exists and we can extract its specific icon.  To ensure that the icon
michael@0:     // is reloaded, we must change the URI used by the XUL image element, for
michael@0:     // example by adding a query parameter.  Since this URI has a "moz-icon"
michael@0:     // scheme, this only works if we add one of the parameters explicitly
michael@0:     // supported by the nsIMozIconURI interface.
michael@0:     if (aOldState != Ci.nsIDownloadManager.DOWNLOAD_FINISHED &&
michael@0:         aOldState != this.dataItem.state) {
michael@0:       this._element.setAttribute("image", this.image + "&state=normal");
michael@0: 
michael@0:       // We assume the existence of the target of a download that just completed
michael@0:       // successfully, without checking the condition in the background.  If the
michael@0:       // panel is already open, this will take effect immediately.  If the panel
michael@0:       // is opened later, a new background existence check will be performed.
michael@0:       this._element.setAttribute("exists", "true");
michael@0:     }
michael@0: 
michael@0:     // Update the user interface after switching states.
michael@0:     this._element.setAttribute("state", this.dataItem.state);
michael@0:     this._updateProgress();
michael@0:     this._updateStatusLine();
michael@0:   },
michael@0: 
michael@0:   /**
michael@0:    * Called when the download progress has changed.
michael@0:    */
michael@0:   onProgressChange: function DVI_onProgressChange() {
michael@0:     this._updateProgress();
michael@0:     this._updateStatusLine();
michael@0:   },
michael@0: 
michael@0:   //////////////////////////////////////////////////////////////////////////////
michael@0:   //// Functions for updating the user interface
michael@0: 
michael@0:   /**
michael@0:    * Updates the progress bar.
michael@0:    */
michael@0:   _updateProgress: function DVI_updateProgress() {
michael@0:     if (this.dataItem.starting) {
michael@0:       // Before the download starts, the progress meter has its initial value.
michael@0:       this._element.setAttribute("progressmode", "normal");
michael@0:       this._element.setAttribute("progress", "0");
michael@0:     } else if (this.dataItem.state == Ci.nsIDownloadManager.DOWNLOAD_SCANNING ||
michael@0:                this.dataItem.percentComplete == -1) {
michael@0:       // We might not know the progress of a running download, and we don't know
michael@0:       // the remaining time during the malware scanning phase.
michael@0:       this._element.setAttribute("progressmode", "undetermined");
michael@0:     } else {
michael@0:       // This is a running download of which we know the progress.
michael@0:       this._element.setAttribute("progressmode", "normal");
michael@0:       this._element.setAttribute("progress", this.dataItem.percentComplete);
michael@0:     }
michael@0: 
michael@0:     // Find the progress element as soon as the download binding is accessible.
michael@0:     if (!this._progressElement) {
michael@0:       this._progressElement =
michael@0:            document.getAnonymousElementByAttribute(this._element, "anonid",
michael@0:                                                    "progressmeter");
michael@0:     }
michael@0: 
michael@0:     // Dispatch the ValueChange event for accessibility, if possible.
michael@0:     if (this._progressElement) {
michael@0:       let event = document.createEvent("Events");
michael@0:       event.initEvent("ValueChange", true, true);
michael@0:       this._progressElement.dispatchEvent(event);
michael@0:     }
michael@0:   },
michael@0: 
michael@0:   /**
michael@0:    * Updates the main status line, including bytes transferred, bytes total,
michael@0:    * download rate, and time remaining.
michael@0:    */
michael@0:   _updateStatusLine: function DVI_updateStatusLine() {
michael@0:     const nsIDM = Ci.nsIDownloadManager;
michael@0: 
michael@0:     let status = "";
michael@0:     let statusTip = "";
michael@0: 
michael@0:     if (this.dataItem.paused) {
michael@0:       let transfer = DownloadUtils.getTransferTotal(this.dataItem.currBytes,
michael@0:                                                     this.dataItem.maxBytes);
michael@0: 
michael@0:       // We use the same XUL label to display both the state and the amount
michael@0:       // transferred, for example "Paused -  1.1 MB".
michael@0:       status = DownloadsCommon.strings.statusSeparatorBeforeNumber(
michael@0:                                             DownloadsCommon.strings.statePaused,
michael@0:                                             transfer);
michael@0:     } else if (this.dataItem.state == nsIDM.DOWNLOAD_DOWNLOADING) {
michael@0:       // We don't show the rate for each download in order to reduce clutter.
michael@0:       // The remaining time per download is likely enough information for the
michael@0:       // panel.
michael@0:       [status] =
michael@0:         DownloadUtils.getDownloadStatusNoRate(this.dataItem.currBytes,
michael@0:                                               this.dataItem.maxBytes,
michael@0:                                               this.dataItem.speed,
michael@0:                                               this.lastEstimatedSecondsLeft);
michael@0: 
michael@0:       // We are, however, OK with displaying the rate in the tooltip.
michael@0:       let newEstimatedSecondsLeft;
michael@0:       [statusTip, newEstimatedSecondsLeft] =
michael@0:         DownloadUtils.getDownloadStatus(this.dataItem.currBytes,
michael@0:                                         this.dataItem.maxBytes,
michael@0:                                         this.dataItem.speed,
michael@0:                                         this.lastEstimatedSecondsLeft);
michael@0:       this.lastEstimatedSecondsLeft = newEstimatedSecondsLeft;
michael@0:     } else if (this.dataItem.starting) {
michael@0:       status = DownloadsCommon.strings.stateStarting;
michael@0:     } else if (this.dataItem.state == nsIDM.DOWNLOAD_SCANNING) {
michael@0:       status = DownloadsCommon.strings.stateScanning;
michael@0:     } else if (!this.dataItem.inProgress) {
michael@0:       let stateLabel = function () {
michael@0:         let s = DownloadsCommon.strings;
michael@0:         switch (this.dataItem.state) {
michael@0:           case nsIDM.DOWNLOAD_FAILED:           return s.stateFailed;
michael@0:           case nsIDM.DOWNLOAD_CANCELED:         return s.stateCanceled;
michael@0:           case nsIDM.DOWNLOAD_BLOCKED_PARENTAL: return s.stateBlockedParentalControls;
michael@0:           case nsIDM.DOWNLOAD_BLOCKED_POLICY:   return s.stateBlockedPolicy;
michael@0:           case nsIDM.DOWNLOAD_DIRTY:            return s.stateDirty;
michael@0:           case nsIDM.DOWNLOAD_FINISHED:         return this._fileSizeText;
michael@0:         }
michael@0:         return null;
michael@0:       }.apply(this);
michael@0: 
michael@0:       let [displayHost, fullHost] =
michael@0:         DownloadUtils.getURIHost(this.dataItem.referrer || this.dataItem.uri);
michael@0: 
michael@0:       let end = new Date(this.dataItem.endTime);
michael@0:       let [displayDate, fullDate] = DownloadUtils.getReadableDates(end);
michael@0: 
michael@0:       // We use the same XUL label to display the state, the host name, and the
michael@0:       // end time, for example "Canceled - 222.net - 11:15" or "1.1 MB -
michael@0:       // website2.com - Yesterday".  We show the full host and the complete date
michael@0:       // in the tooltip.
michael@0:       let firstPart = DownloadsCommon.strings.statusSeparator(stateLabel,
michael@0:                                                               displayHost);
michael@0:       status = DownloadsCommon.strings.statusSeparator(firstPart, displayDate);
michael@0:       statusTip = DownloadsCommon.strings.statusSeparator(fullHost, fullDate);
michael@0:     }
michael@0: 
michael@0:     this._element.setAttribute("status", status);
michael@0:     this._element.setAttribute("statusTip", statusTip || status);
michael@0:   },
michael@0: 
michael@0:   /**
michael@0:    * Localized string representing the total size of completed downloads, for
michael@0:    * example "1.5 MB" or "Unknown size".
michael@0:    */
michael@0:   get _fileSizeText()
michael@0:   {
michael@0:     // Display the file size, but show "Unknown" for negative sizes.
michael@0:     let fileSize = this.dataItem.maxBytes;
michael@0:     if (fileSize < 0) {
michael@0:       return DownloadsCommon.strings.sizeUnknown;
michael@0:     }
michael@0:     let [size, unit] = DownloadUtils.convertByteUnits(fileSize);
michael@0:     return DownloadsCommon.strings.sizeWithUnits(size, unit);
michael@0:   },
michael@0: 
michael@0:   //////////////////////////////////////////////////////////////////////////////
michael@0:   //// Functions called by the panel
michael@0: 
michael@0:   /**
michael@0:    * Starts checking whether the target file of a finished download is still
michael@0:    * available on disk, and sets an attribute that controls how the item is
michael@0:    * presented visually.
michael@0:    *
michael@0:    * The existence check is executed on a background thread.
michael@0:    */
michael@0:   verifyTargetExists: function DVI_verifyTargetExists() {
michael@0:     // We don't need to check if the download is not finished successfully.
michael@0:     if (!this.dataItem.openable) {
michael@0:       return;
michael@0:     }
michael@0: 
michael@0:     OS.File.exists(this.dataItem.localFile.path).then(
michael@0:       function DVI_RTE_onSuccess(aExists) {
michael@0:         if (aExists) {
michael@0:           this._element.setAttribute("exists", "true");
michael@0:         } else {
michael@0:           this._element.removeAttribute("exists");
michael@0:         }
michael@0:       }.bind(this), Cu.reportError);
michael@0:   },
michael@0: };
michael@0: 
michael@0: ////////////////////////////////////////////////////////////////////////////////
michael@0: //// DownloadsViewController
michael@0: 
michael@0: /**
michael@0:  * Handles part of the user interaction events raised by the downloads list
michael@0:  * widget, in particular the "commands" that apply to multiple items, and
michael@0:  * dispatches the commands that apply to individual items.
michael@0:  */
michael@0: const DownloadsViewController = {
michael@0:   //////////////////////////////////////////////////////////////////////////////
michael@0:   //// Initialization and termination
michael@0: 
michael@0:   initialize: function DVC_initialize()
michael@0:   {
michael@0:     window.controllers.insertControllerAt(0, this);
michael@0:   },
michael@0: 
michael@0:   terminate: function DVC_terminate()
michael@0:   {
michael@0:     window.controllers.removeController(this);
michael@0:   },
michael@0: 
michael@0:   //////////////////////////////////////////////////////////////////////////////
michael@0:   //// nsIController
michael@0: 
michael@0:   supportsCommand: function DVC_supportsCommand(aCommand)
michael@0:   {
michael@0:     // Firstly, determine if this is a command that we can handle.
michael@0:     if (!(aCommand in this.commands) &&
michael@0:         !(aCommand in DownloadsViewItemController.prototype.commands)) {
michael@0:       return false;
michael@0:     }
michael@0:     // Secondly, determine if focus is on a control in the downloads list.
michael@0:     let element = document.commandDispatcher.focusedElement;
michael@0:     while (element && element != DownloadsView.richListBox) {
michael@0:       element = element.parentNode;
michael@0:     }
michael@0:     // We should handle the command only if the downloads list is among the
michael@0:     // ancestors of the focused element.
michael@0:     return !!element;
michael@0:   },
michael@0: 
michael@0:   isCommandEnabled: function DVC_isCommandEnabled(aCommand)
michael@0:   {
michael@0:     // Handle commands that are not selection-specific.
michael@0:     if (aCommand == "downloadsCmd_clearList") {
michael@0:       return DownloadsCommon.getData(window).canRemoveFinished;
michael@0:     }
michael@0: 
michael@0:     // Other commands are selection-specific.
michael@0:     let element = DownloadsView.richListBox.selectedItem;
michael@0:     return element &&
michael@0:            new DownloadsViewItemController(element).isCommandEnabled(aCommand);
michael@0:   },
michael@0: 
michael@0:   doCommand: function DVC_doCommand(aCommand)
michael@0:   {
michael@0:     // If this command is not selection-specific, execute it.
michael@0:     if (aCommand in this.commands) {
michael@0:       this.commands[aCommand].apply(this);
michael@0:       return;
michael@0:     }
michael@0: 
michael@0:     // Other commands are selection-specific.
michael@0:     let element = DownloadsView.richListBox.selectedItem;
michael@0:     if (element) {
michael@0:       // The doCommand function also checks if the command is enabled.
michael@0:       new DownloadsViewItemController(element).doCommand(aCommand);
michael@0:     }
michael@0:   },
michael@0: 
michael@0:   onEvent: function () { },
michael@0: 
michael@0:   //////////////////////////////////////////////////////////////////////////////
michael@0:   //// Other functions
michael@0: 
michael@0:   updateCommands: function DVC_updateCommands()
michael@0:   {
michael@0:     Object.keys(this.commands).forEach(goUpdateCommand);
michael@0:     Object.keys(DownloadsViewItemController.prototype.commands)
michael@0:           .forEach(goUpdateCommand);
michael@0:   },
michael@0: 
michael@0:   //////////////////////////////////////////////////////////////////////////////
michael@0:   //// Selection-independent commands
michael@0: 
michael@0:   /**
michael@0:    * This object contains one key for each command that operates regardless of
michael@0:    * the currently selected item in the list.
michael@0:    */
michael@0:   commands: {
michael@0:     downloadsCmd_clearList: function DVC_downloadsCmd_clearList()
michael@0:     {
michael@0:       DownloadsCommon.getData(window).removeFinished();
michael@0:     }
michael@0:   }
michael@0: };
michael@0: 
michael@0: ////////////////////////////////////////////////////////////////////////////////
michael@0: //// DownloadsViewItemController
michael@0: 
michael@0: /**
michael@0:  * Handles all the user interaction events, in particular the "commands",
michael@0:  * related to a single item in the downloads list widgets.
michael@0:  */
michael@0: function DownloadsViewItemController(aElement) {
michael@0:   let downloadGuid = aElement.getAttribute("downloadGuid");
michael@0:   this.dataItem = DownloadsCommon.getData(window).dataItems[downloadGuid];
michael@0: }
michael@0: 
michael@0: DownloadsViewItemController.prototype = {
michael@0:   //////////////////////////////////////////////////////////////////////////////
michael@0:   //// Command dispatching
michael@0: 
michael@0:   /**
michael@0:    * The DownloadDataItem controlled by this object.
michael@0:    */
michael@0:   dataItem: null,
michael@0: 
michael@0:   isCommandEnabled: function DVIC_isCommandEnabled(aCommand)
michael@0:   {
michael@0:     switch (aCommand) {
michael@0:       case "downloadsCmd_open": {
michael@0:         return this.dataItem.openable && this.dataItem.localFile.exists();
michael@0:       }
michael@0:       case "downloadsCmd_show": {
michael@0:         return this.dataItem.localFile.exists() ||
michael@0:                this.dataItem.partFile.exists();
michael@0:       }
michael@0:       case "downloadsCmd_pauseResume":
michael@0:         return this.dataItem.inProgress && this.dataItem.resumable;
michael@0:       case "downloadsCmd_retry":
michael@0:         return this.dataItem.canRetry;
michael@0:       case "downloadsCmd_openReferrer":
michael@0:         return !!this.dataItem.referrer;
michael@0:       case "cmd_delete":
michael@0:       case "downloadsCmd_cancel":
michael@0:       case "downloadsCmd_copyLocation":
michael@0:       case "downloadsCmd_doDefault":
michael@0:         return true;
michael@0:     }
michael@0:     return false;
michael@0:   },
michael@0: 
michael@0:   doCommand: function DVIC_doCommand(aCommand)
michael@0:   {
michael@0:     if (this.isCommandEnabled(aCommand)) {
michael@0:       this.commands[aCommand].apply(this);
michael@0:     }
michael@0:   },
michael@0: 
michael@0:   //////////////////////////////////////////////////////////////////////////////
michael@0:   //// Item commands
michael@0: 
michael@0:   /**
michael@0:    * This object contains one key for each command that operates on this item.
michael@0:    *
michael@0:    * In commands, the "this" identifier points to the controller item.
michael@0:    */
michael@0:   commands: {
michael@0:     cmd_delete: function DVIC_cmd_delete()
michael@0:     {
michael@0:       this.dataItem.remove();
michael@0:       PlacesUtils.bhistory.removePage(NetUtil.newURI(this.dataItem.uri));
michael@0:     },
michael@0: 
michael@0:     downloadsCmd_cancel: function DVIC_downloadsCmd_cancel()
michael@0:     {
michael@0:       this.dataItem.cancel();
michael@0:     },
michael@0: 
michael@0:     downloadsCmd_open: function DVIC_downloadsCmd_open()
michael@0:     {
michael@0:       this.dataItem.openLocalFile();
michael@0: 
michael@0:       // We explicitly close the panel here to give the user the feedback that
michael@0:       // their click has been received, and we're handling the action.
michael@0:       // Otherwise, we'd have to wait for the file-type handler to execute
michael@0:       // before the panel would close. This also helps to prevent the user from
michael@0:       // accidentally opening a file several times.
michael@0:       DownloadsPanel.hidePanel();
michael@0:     },
michael@0: 
michael@0:     downloadsCmd_show: function DVIC_downloadsCmd_show()
michael@0:     {
michael@0:       this.dataItem.showLocalFile();
michael@0: 
michael@0:       // We explicitly close the panel here to give the user the feedback that
michael@0:       // their click has been received, and we're handling the action.
michael@0:       // Otherwise, we'd have to wait for the operating system file manager
michael@0:       // window to open before the panel closed. This also helps to prevent the
michael@0:       // user from opening the containing folder several times.
michael@0:       DownloadsPanel.hidePanel();
michael@0:     },
michael@0: 
michael@0:     downloadsCmd_pauseResume: function DVIC_downloadsCmd_pauseResume()
michael@0:     {
michael@0:       this.dataItem.togglePauseResume();
michael@0:     },
michael@0: 
michael@0:     downloadsCmd_retry: function DVIC_downloadsCmd_retry()
michael@0:     {
michael@0:       this.dataItem.retry();
michael@0:     },
michael@0: 
michael@0:     downloadsCmd_openReferrer: function DVIC_downloadsCmd_openReferrer()
michael@0:     {
michael@0:       openURL(this.dataItem.referrer);
michael@0:     },
michael@0: 
michael@0:     downloadsCmd_copyLocation: function DVIC_downloadsCmd_copyLocation()
michael@0:     {
michael@0:       let clipboard = Cc["@mozilla.org/widget/clipboardhelper;1"]
michael@0:                       .getService(Ci.nsIClipboardHelper);
michael@0:       clipboard.copyString(this.dataItem.uri, document);
michael@0:     },
michael@0: 
michael@0:     downloadsCmd_doDefault: function DVIC_downloadsCmd_doDefault()
michael@0:     {
michael@0:       const nsIDM = Ci.nsIDownloadManager;
michael@0: 
michael@0:       // Determine the default command for the current item.
michael@0:       let defaultCommand = function () {
michael@0:         switch (this.dataItem.state) {
michael@0:           case nsIDM.DOWNLOAD_NOTSTARTED:       return "downloadsCmd_cancel";
michael@0:           case nsIDM.DOWNLOAD_FINISHED:         return "downloadsCmd_open";
michael@0:           case nsIDM.DOWNLOAD_FAILED:           return "downloadsCmd_retry";
michael@0:           case nsIDM.DOWNLOAD_CANCELED:         return "downloadsCmd_retry";
michael@0:           case nsIDM.DOWNLOAD_PAUSED:           return "downloadsCmd_pauseResume";
michael@0:           case nsIDM.DOWNLOAD_QUEUED:           return "downloadsCmd_cancel";
michael@0:           case nsIDM.DOWNLOAD_BLOCKED_PARENTAL: return "downloadsCmd_openReferrer";
michael@0:           case nsIDM.DOWNLOAD_SCANNING:         return "downloadsCmd_show";
michael@0:           case nsIDM.DOWNLOAD_DIRTY:            return "downloadsCmd_openReferrer";
michael@0:           case nsIDM.DOWNLOAD_BLOCKED_POLICY:   return "downloadsCmd_openReferrer";
michael@0:         }
michael@0:         return "";
michael@0:       }.apply(this);
michael@0:       if (defaultCommand && this.isCommandEnabled(defaultCommand))
michael@0:         this.doCommand(defaultCommand);
michael@0:     }
michael@0:   }
michael@0: };
michael@0: 
michael@0: 
michael@0: ////////////////////////////////////////////////////////////////////////////////
michael@0: //// DownloadsSummary
michael@0: 
michael@0: /**
michael@0:  * Manages the summary at the bottom of the downloads panel list if the number
michael@0:  * of items in the list exceeds the panels limit.
michael@0:  */
michael@0: const DownloadsSummary = {
michael@0: 
michael@0:   /**
michael@0:    * Sets the active state of the summary. When active, the summary subscribes
michael@0:    * to the DownloadsCommon DownloadsSummaryData singleton.
michael@0:    *
michael@0:    * @param aActive
michael@0:    *        Set to true to activate the summary.
michael@0:    */
michael@0:   set active(aActive)
michael@0:   {
michael@0:     if (aActive == this._active || !this._summaryNode) {
michael@0:       return this._active;
michael@0:     }
michael@0:     if (aActive) {
michael@0:       DownloadsCommon.getSummary(window, DownloadsView.kItemCountLimit)
michael@0:                      .refreshView(this);
michael@0:     } else {
michael@0:       DownloadsFooter.showingSummary = false;
michael@0:     }
michael@0: 
michael@0:     return this._active = aActive;
michael@0:   },
michael@0: 
michael@0:   /**
michael@0:    * Returns the active state of the downloads summary.
michael@0:    */
michael@0:   get active() this._active,
michael@0: 
michael@0:   _active: false,
michael@0: 
michael@0:   /**
michael@0:    * Sets whether or not we show the progress bar.
michael@0:    *
michael@0:    * @param aShowingProgress
michael@0:    *        True if we should show the progress bar.
michael@0:    */
michael@0:   set showingProgress(aShowingProgress)
michael@0:   {
michael@0:     if (aShowingProgress) {
michael@0:       this._summaryNode.setAttribute("inprogress", "true");
michael@0:     } else {
michael@0:       this._summaryNode.removeAttribute("inprogress");
michael@0:     }
michael@0:     // If progress isn't being shown, then we simply do not show the summary.
michael@0:     return DownloadsFooter.showingSummary = aShowingProgress;
michael@0:   },
michael@0: 
michael@0:   /**
michael@0:    * Sets the amount of progress that is visible in the progress bar.
michael@0:    *
michael@0:    * @param aValue
michael@0:    *        A value between 0 and 100 to represent the progress of the
michael@0:    *        summarized downloads.
michael@0:    */
michael@0:   set percentComplete(aValue)
michael@0:   {
michael@0:     if (this._progressNode) {
michael@0:       this._progressNode.setAttribute("value", aValue);
michael@0:     }
michael@0:     return aValue;
michael@0:   },
michael@0: 
michael@0:   /**
michael@0:    * Sets the description for the download summary.
michael@0:    *
michael@0:    * @param aValue
michael@0:    *        A string representing the description of the summarized
michael@0:    *        downloads.
michael@0:    */
michael@0:   set description(aValue)
michael@0:   {
michael@0:     if (this._descriptionNode) {
michael@0:       this._descriptionNode.setAttribute("value", aValue);
michael@0:       this._descriptionNode.setAttribute("tooltiptext", aValue);
michael@0:     }
michael@0:     return aValue;
michael@0:   },
michael@0: 
michael@0:   /**
michael@0:    * Sets the details for the download summary, such as the time remaining,
michael@0:    * the amount of bytes transferred, etc.
michael@0:    *
michael@0:    * @param aValue
michael@0:    *        A string representing the details of the summarized
michael@0:    *        downloads.
michael@0:    */
michael@0:   set details(aValue)
michael@0:   {
michael@0:     if (this._detailsNode) {
michael@0:       this._detailsNode.setAttribute("value", aValue);
michael@0:       this._detailsNode.setAttribute("tooltiptext", aValue);
michael@0:     }
michael@0:     return aValue;
michael@0:   },
michael@0: 
michael@0:   /**
michael@0:    * Focuses the root element of the summary.
michael@0:    */
michael@0:   focus: function()
michael@0:   {
michael@0:     if (this._summaryNode) {
michael@0:       this._summaryNode.focus();
michael@0:     }
michael@0:   },
michael@0: 
michael@0:   /**
michael@0:    * Respond to keydown events on the Downloads Summary node.
michael@0:    *
michael@0:    * @param aEvent
michael@0:    *        The keydown event being handled.
michael@0:    */
michael@0:   onKeyDown: function DS_onKeyDown(aEvent)
michael@0:   {
michael@0:     if (aEvent.charCode == " ".charCodeAt(0) ||
michael@0:         aEvent.keyCode == KeyEvent.DOM_VK_RETURN) {
michael@0:       DownloadsPanel.showDownloadsHistory();
michael@0:     }
michael@0:   },
michael@0: 
michael@0:   /**
michael@0:    * Respond to click events on the Downloads Summary node.
michael@0:    *
michael@0:    * @param aEvent
michael@0:    *        The click event being handled.
michael@0:    */
michael@0:   onClick: function DS_onClick(aEvent)
michael@0:   {
michael@0:     DownloadsPanel.showDownloadsHistory();
michael@0:   },
michael@0: 
michael@0:   /**
michael@0:    * Element corresponding to the root of the downloads summary.
michael@0:    */
michael@0:   get _summaryNode()
michael@0:   {
michael@0:     let node = document.getElementById("downloadsSummary");
michael@0:     if (!node) {
michael@0:       return null;
michael@0:     }
michael@0:     delete this._summaryNode;
michael@0:     return this._summaryNode = node;
michael@0:   },
michael@0: 
michael@0:   /**
michael@0:    * Element corresponding to the progress bar in the downloads summary.
michael@0:    */
michael@0:   get _progressNode()
michael@0:   {
michael@0:     let node = document.getElementById("downloadsSummaryProgress");
michael@0:     if (!node) {
michael@0:       return null;
michael@0:     }
michael@0:     delete this._progressNode;
michael@0:     return this._progressNode = node;
michael@0:   },
michael@0: 
michael@0:   /**
michael@0:    * Element corresponding to the main description of the downloads
michael@0:    * summary.
michael@0:    */
michael@0:   get _descriptionNode()
michael@0:   {
michael@0:     let node = document.getElementById("downloadsSummaryDescription");
michael@0:     if (!node) {
michael@0:       return null;
michael@0:     }
michael@0:     delete this._descriptionNode;
michael@0:     return this._descriptionNode = node;
michael@0:   },
michael@0: 
michael@0:   /**
michael@0:    * Element corresponding to the secondary description of the downloads
michael@0:    * summary.
michael@0:    */
michael@0:   get _detailsNode()
michael@0:   {
michael@0:     let node = document.getElementById("downloadsSummaryDetails");
michael@0:     if (!node) {
michael@0:       return null;
michael@0:     }
michael@0:     delete this._detailsNode;
michael@0:     return this._detailsNode = node;
michael@0:   }
michael@0: }
michael@0: 
michael@0: ////////////////////////////////////////////////////////////////////////////////
michael@0: //// DownloadsFooter
michael@0: 
michael@0: /**
michael@0:  * Manages events sent to to the footer vbox, which contains both the
michael@0:  * DownloadsSummary as well as the "Show All Downloads" button.
michael@0:  */
michael@0: const DownloadsFooter = {
michael@0: 
michael@0:   /**
michael@0:    * Focuses the appropriate element within the footer. If the summary
michael@0:    * is visible, focus it. If not, focus the "Show All Downloads"
michael@0:    * button.
michael@0:    */
michael@0:   focus: function DF_focus()
michael@0:   {
michael@0:     if (this._showingSummary) {
michael@0:       DownloadsSummary.focus();
michael@0:     } else {
michael@0:       DownloadsView.downloadsHistory.focus();
michael@0:     }
michael@0:   },
michael@0: 
michael@0:   _showingSummary: false,
michael@0: 
michael@0:   /**
michael@0:    * Sets whether or not the Downloads Summary should be displayed in the
michael@0:    * footer. If not, the "Show All Downloads" button is shown instead.
michael@0:    */
michael@0:   set showingSummary(aValue)
michael@0:   {
michael@0:     if (this._footerNode) {
michael@0:       if (aValue) {
michael@0:         this._footerNode.setAttribute("showingsummary", "true");
michael@0:       } else {
michael@0:         this._footerNode.removeAttribute("showingsummary");
michael@0:       }
michael@0:       this._showingSummary = aValue;
michael@0:     }
michael@0:     return aValue;
michael@0:   },
michael@0: 
michael@0:   /**
michael@0:    * Element corresponding to the footer of the downloads panel.
michael@0:    */
michael@0:   get _footerNode()
michael@0:   {
michael@0:     let node = document.getElementById("downloadsFooter");
michael@0:     if (!node) {
michael@0:       return null;
michael@0:     }
michael@0:     delete this._footerNode;
michael@0:     return this._footerNode = node;
michael@0:   }
michael@0: };