Bug 815203 - [system] handle the app install restart when the homescr…

…een starts it r=etienne r=arcturus

We used to display the notification as soon as we got the applicationinstall
event. Now we display the notification in the notification center only when
the first progress event is fired on the app object.

When an app install is restarted, we'll get only progress events, then it
fits correctly in our new way of displaying the notification.

We take also great care to remove the handlers on the app object only if
they're our own handlers.

We also have to add the handlers on pending apps during init to listen for
app install restarts.

apps/system/js/app_install_manager.js

@@ -20,7 +20,7 @@ var AppInstallManager = {
 
     this.notifContainer =
             document.getElementById('install-manager-notification-container');
-    this.installNotifications = {};
+    this.appInfos = {};
 
     window.addEventListener('mozChromeEvent',
       (function ai_handleChromeEvent(e) {
@@ -43,6 +43,34 @@ var AppInstallManager = {
       this.handleConfirmDownloadCancel.bind(this);
     this.downloadCancelDialog.querySelector('.cancel').onclick =
       this.handleCancelDownloadCancel.bind(this);
+
+    // bind these handlers so that we can have only one instance and check
+    // them later on
+    ['handleDownloadSuccess',
+     'handleDownloadError',
+     'handleProgress',
+     'handleApplicationReady'
+    ].forEach(function(name) {
+      this[name] = this[name].bind(this);
+    }, this);
+
+    window.addEventListener('applicationready',
+        this.handleApplicationReady);
+  },
+
+  handleApplicationReady: function ai_handleApplicationReady(e) {
+    window.removeEventListener('applicationready',
+        this.handleApplicationReady);
+
+    var apps = e.detail.applications;
+
+    Object.keys(apps)
+      .map(function(key) { return apps[key]; })
+      .forEach(this.prepareForDownload, this);
+  },
+
+  handleApplicationInstall: function ai_handleApplicationInstallEvent(e) {
+    this.prepareForDownload(e.detail.application);
   },
 
   handleAppInstallPrompt: function ai_handleInstallPrompt(detail) {
@@ -100,33 +128,33 @@ var AppInstallManager = {
     this.dialog.classList.remove('visible');
   },
 
-  handleApplicationInstall: function ai_handleApplicationInstall(e) {
-    var app = e.detail.application,
-        manifestURL = app.manifestURL;
+  prepareForDownload: function ai_prepareForDownload(app) {
+    var manifestURL = app.manifestURL;
 
     if (app.installState === 'installed') {
       // nothing more to do here, everything is already done
       return;
     }
-    StatusBar.incSystemDownloads();
-    this.addNotification(app);
 
-    app.ondownloadsuccess = this.handleDownloadSuccess.bind(this);
-    app.ondownloaderror = this.handleDownloadError.bind(this);
-    app.onprogress = this.handleProgress.bind(this);
+    this.appInfos[manifestURL] = {};
+
+    // these methods are already bound to |this|
+    app.ondownloadsuccess = this.handleDownloadSuccess;
+    app.ondownloaderror = this.handleDownloadError;
+    app.onprogress = this.handleProgress;
   },
 
   handleDownloadSuccess: function ai_handleDownloadSuccess(evt) {
     var app = evt.application;
-    this.finishDownload(app);
+    this.onDownloadStop(app);
+    this.onDownloadFinish(app);
   },
 
   handleDownloadError: function ai_handleDownloadError(evt) {
     var app = evt.application;
     var _ = navigator.mozL10n.get;
     var manifest = app.manifest || app.updateManifest;
     var name = manifest.name;
-    StatusBar.decSystemDownloads();
 
     var error = app.downloadError;
 
@@ -143,23 +171,52 @@ var AppInstallManager = {
         SystemBanner.show(msg);
     }
 
-    this.finishDownload(app);
+    this.onDownloadStop(app);
+  },
+
+  onDownloadStart: function ai_onDownloadStart(app) {
+    if (! this.hasNotification(app)) {
+      StatusBar.incSystemDownloads();
+      this.addNotification(app);
+    }
+  },
+
+  onDownloadStop: function ai_onDownloadStop(app) {
+    if (this.hasNotification(app)) {
+      StatusBar.decSystemDownloads();
+      this.removeNotification(app);
+    }
   },
 
-  finishDownload: function ai_cleanUp(app) {
-    StatusBar.decSystemDownloads();
-    this.removeNotification(app);
-    app.ondownloadsuccess = null;
-    app.ondownloaderror = null;
-    app.onprogress = null;
+  hasNotification: function ai_hasNotification(app) {
+    var appInfo = this.appInfos[app.manifestURL];
+    return appInfo && !!appInfo.installNotification;
+  },
+
+  onDownloadFinish: function ai_onDownloadFinish(app) {
+    delete this.appInfos[app.manifestURL];
+
+    // check if these are our handlers before removing them
+    if (app.ondownloadsuccess === this.handleDownloadSuccess) {
+      app.ondownloadsuccess = null;
+    }
+
+    if (app.ondownloaderror === this.handleDownloadError) {
+      app.ondownloaderror = null;
+    }
+
+    if (app.onprogress === this.handleProgress) {
+      app.onprogress = null;
+    }
   },
 
   addNotification: function ai_addNotification(app) {
     // should be unique (this is used already in applications.js)
     var manifestURL = app.manifestURL,
-        manifest = app.manifest || app.updateManifest;
+        manifest = app.manifest || app.updateManifest,
+        appInfo = this.appInfos[manifestURL];
 
-    if (this.installNotifications[manifestURL]) {
+    if (appInfo.installNotification) {
       return;
     }
 
@@ -182,36 +239,33 @@ var AppInstallManager = {
 
     newNode.querySelector('.message').textContent = message;
 
-    var progressNode = newNode.querySelector('progress');
-
-    var size = manifest.size;
+    var size = manifest.size,
+        progressNode = newNode.querySelector('progress');
     if (size) {
       progressNode.max = size;
-      progressNode.value = 0;
-      message = _('downloadingAppProgress',
-        {
-          progress: this.humanizeSize(0),
-          max: this.humanizeSize(size)
-        });
-    } else {
-      message = navigator.mozL10n.get(
-          'downloadingAppProgressNoMax', { progress: 0 });
+      appInfo.hasMax = true;
     }
-    progressNode.textContent = message;
 
-    this.installNotifications[manifestURL] = newNode;
+    appInfo.installNotification = newNode;
     NotificationScreen.incExternalNotifications();
   },
 
+  getNotificationProgressNode: function ai_getNotificationProgressNode(app) {
+    var appInfo = this.appInfos[app.manifestURL];
+    var progressNode = appInfo
+      && appInfo.installNotification
+      && appInfo.installNotification.querySelector('progress');
+    return progressNode || null;
+  },
+
   handleProgress: function ai_handleProgress(evt) {
-    var app = evt.application;
-    var notifNode = this.installNotifications[app.manifestURL];
+    var app = evt.application,
+        appInfo = this.appInfos[app.manifestURL];
+
+    this.onDownloadStart(app);
 
-    if (!notifNode) {
-      return;
-    }
 
-    var progressNode = notifNode.querySelector('progress');
+    var progressNode = this.getNotificationProgressNode(app);
     var message;
     var _ = navigator.mozL10n.get;
 
@@ -220,31 +274,31 @@ var AppInstallManager = {
       // handle the null and undefined cases as well
       message = _('downloadingAppProgressIndeterminate');
       progressNode.value = undefined; // switch to indeterminate state
-    } else if (progressNode.position === -1) {
-      // already in indeterminate state, means we have no max
-      message = _('downloadingAppProgressNoMax',
-                                      { progress: app.progress });
-    } else {
+    } else if (appInfo.hasMax) {
       message = _('downloadingAppProgress',
         {
           progress: this.humanizeSize(app.progress),
           max: this.humanizeSize(progressNode.max)
         });
       progressNode.value = app.progress;
+    } else {
+      message = _('downloadingAppProgressNoMax',
+                 { progress: this.humanizeSize(app.progress) });
     }
     progressNode.textContent = message;
   },
 
   removeNotification: function ai_removeNotification(app) {
     var manifestURL = app.manifestURL,
-        node = this.installNotifications[manifestURL];
+        appInfo = this.appInfos[manifestURL],
+        node = appInfo.installNotification;
 
     if (!node) {
       return;
     }
 
     node.parentNode.removeChild(node);
-    delete this.installNotifications[manifestURL];
+    delete appInfo.installNotification;
     NotificationScreen.decExternalNotifications();
   },