Watch desktop files for changes

This introduces a slightly clumsy "destroy" signal for AppSection to notify
outsiders that the desktop file was deleted.  This will do for now, but a
larger refactoring which pulls all the desktop-file-reading code out of
appsection is in order.

2 files changed, 129 insertions, 26 deletions

diff --git a/src/app-section.c b/src/app-section.c
index bed1302..58f1612 100644
--- a/src/app-section.c
+++ b/src/app-section.c
@@ -37,6 +37,7 @@ with this program.  If not, see <http://www.gnu.org/licenses/>.
 struct _AppSectionPrivate
 {
 	GDesktopAppInfo * appinfo;
+	GFileMonitor *desktop_file_monitor;
 	guint unreadcount;
 
 	IndicatorDesktopShortcuts * ids;
@@ -64,6 +65,7 @@ enum {
 };
 
 static GParamSpec *properties[NUM_PROPERTIES];
+guint destroy_signal;
 
 /* Prototypes */
 static void app_section_class_init   (AppSectionClass *klass);
@@ -98,6 +100,11 @@ static void	action_removed			(GActionGroup *group,
 						 const gchar *action_name,
 						 gpointer user_data);
 static gboolean	action_draws_attention		(GVariant *state);
+static void	desktop_file_changed_cb		(GFileMonitor      *monitor,
+						 GFile             *file,
+						 GFile             *other_file,
+						 GFileMonitorEvent  event,
+						 gpointer           user_data);
 
 /* GObject Boilerplate */
 G_DEFINE_TYPE (AppSection, app_section, G_TYPE_OBJECT);
@@ -138,6 +145,14 @@ app_section_class_init (AppSectionClass *klass)
 								  G_PARAM_READABLE);
 
 	g_object_class_install_properties (object_class, NUM_PROPERTIES, properties);
+
+	destroy_signal = g_signal_new ("destroy",
+				       APP_SECTION_TYPE,
+				       G_SIGNAL_RUN_FIRST,
+				       0,
+				       NULL, NULL,
+				       g_cclosure_marshal_VOID__VOID,
+				       G_TYPE_NONE, 0);
 }
 
 static void
@@ -209,12 +224,18 @@ app_section_set_property (GObject      *object,
 		G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
 	}
 }
+
 static void
 app_section_dispose (GObject *object)
 {
 	AppSection * self = APP_SECTION(object);
 	AppSectionPrivate * priv = self->priv;
 
+	if (priv->desktop_file_monitor) {
+		g_signal_handlers_disconnect_by_func (priv->desktop_file_monitor, desktop_file_changed_cb, self);
+		g_clear_object (&priv->desktop_file_monitor);
+	}
+
 	g_clear_object (&priv->menu);
 	g_clear_object (&priv->static_shortcuts);
 
@@ -289,6 +310,9 @@ keyfile_loaded (GObject *source_object,
 							       G_KEY_FILE_DESKTOP_GROUP,
 							       "X-MessagingMenu-UsesChatSection",
 							       &error);
+
+	g_object_notify_by_pspec (G_OBJECT (self), properties[PROP_USES_CHAT_STATUS]);
+
 	if (error) {
 		if (error->code != G_KEY_FILE_ERROR_KEY_NOT_FOUND) {
 			g_warning ("could not read X-MessagingMenu-UsesChatSection: %s",
@@ -298,34 +322,48 @@ keyfile_loaded (GObject *source_object,
 		goto out;
 	}
 
-	if (self->priv->uses_chat_status)
-		g_object_notify_by_pspec (G_OBJECT (self), properties[PROP_USES_CHAT_STATUS]);
-
 out:
 	g_key_file_free (keyfile);
 	g_free (contents);
 }
 
 static void
-app_section_set_app_info (AppSection *self,
-			  GDesktopAppInfo *appinfo)
+g_menu_clear (GMenu *menu)
+{
+	gint n_items = g_menu_model_get_n_items (G_MENU_MODEL (menu));
+
+	while (n_items--)
+		g_menu_remove (menu, 0);
+}
+
+static void
+g_simple_action_group_clear (GSimpleActionGroup *group)
+{
+	gchar **actions;
+	gchar **it;
+
+	actions = g_action_group_list_actions (G_ACTION_GROUP (group));
+	for (it = actions; *it; it++)
+		g_simple_action_group_remove (group, *it);
+
+	g_strfreev (actions);
+}
+
+static void
+app_section_update_menu (AppSection *self)
 {
 	AppSectionPrivate *priv = self->priv;
 	GSimpleAction *launch;
 	GFile *keyfile;
 	GMenuItem *item;
 	gchar *iconstr;
+	gboolean is_running;
 
-	g_return_if_fail (priv->appinfo == NULL);
+	g_menu_clear (priv->menu);
+	g_simple_action_group_clear (priv->static_shortcuts);
 
-	if (appinfo == NULL) {
-		g_warning ("appinfo must not be NULL");
-		return;
-	}
-
-	priv->appinfo = g_object_ref (appinfo);
-
-	launch = g_simple_action_new_stateful ("launch", NULL, g_variant_new_boolean (FALSE));
+	is_running = priv->name_watch_id > 0;
+	launch = g_simple_action_new_stateful ("launch", NULL, g_variant_new_boolean (is_running));
 	g_signal_connect (launch, "activate", G_CALLBACK (activate_cb), self);
 	g_signal_connect (launch, "change-state", G_CALLBACK (launch_action_change_state), self);
 	g_simple_action_group_insert (priv->static_shortcuts, G_ACTION (launch));
@@ -366,14 +404,65 @@ app_section_set_app_info (AppSection *self,
 
 	keyfile = g_file_new_for_path (g_desktop_app_info_get_filename (priv->appinfo));
 	g_file_load_contents_async (keyfile, NULL, keyfile_loaded, self);
-	g_object_unref (keyfile);
 
-	g_object_notify_by_pspec (G_OBJECT (self), properties[PROP_APPINFO]);
 	g_object_notify_by_pspec (G_OBJECT (self), properties[PROP_ACTIONS]);
 
+	g_object_unref (keyfile);
 	g_object_unref (launch);
 }
 
+static void
+desktop_file_changed_cb (GFileMonitor      *monitor,
+			 GFile             *file,
+			 GFile             *other_file,
+			 GFileMonitorEvent  event,
+			 gpointer           user_data)
+{
+	AppSection *self = user_data;
+
+	if (event == G_FILE_MONITOR_EVENT_CHANGED) {
+		app_section_update_menu (self);
+	}
+	else if (event == G_FILE_MONITOR_EVENT_DELETED ||
+		 event == G_FILE_MONITOR_EVENT_UNMOUNTED) {
+		g_signal_emit (self, destroy_signal, 0);
+	}
+}
+
+static void
+app_section_set_app_info (AppSection *self,
+			  GDesktopAppInfo *appinfo)
+{
+	AppSectionPrivate *priv = self->priv;
+	GFile *desktop_file;
+	GError *error = NULL;
+
+	g_return_if_fail (priv->appinfo == NULL);
+	g_return_if_fail (priv->desktop_file_monitor == NULL);
+
+	if (appinfo == NULL) {
+		g_warning ("appinfo must not be NULL");
+		return;
+	}
+
+	priv->appinfo = g_object_ref (appinfo);
+
+	desktop_file = g_file_new_for_path (g_desktop_app_info_get_filename (appinfo));
+	priv->desktop_file_monitor = g_file_monitor (desktop_file, G_FILE_MONITOR_SEND_MOVED, NULL, &error);
+	if (priv->desktop_file_monitor == NULL) {
+		g_warning ("unable to watch desktop file: %s", error->message);
+		g_error_free (error);
+	}
+	g_signal_connect (priv->desktop_file_monitor, "changed",
+			  G_CALLBACK (desktop_file_changed_cb), self);
+
+	g_object_notify_by_pspec (G_OBJECT (self), properties[PROP_APPINFO]);
+
+	app_section_update_menu (self);
+
+	g_object_unref (desktop_file);
+}
+
 AppSection *
 app_section_new (GDesktopAppInfo *appinfo)
 {
diff --git a/src/messages-service.c b/src/messages-service.c
index 15c5123..ed9bfe4 100644
--- a/src/messages-service.c
+++ b/src/messages-service.c
@@ -45,7 +45,6 @@ static GMenu *menu;
 static GMenuModel *chat_section;
 static GSettings *settings;
 
-
 static gchar *
 g_app_info_get_simple_id (GAppInfo *appinfo)
 {
@@ -138,6 +137,23 @@ uses_chat_status_changed (GObject *object,
 	g_object_unref (first_section);
 }
 
+static void
+remove_section (AppSection  *section,
+		const gchar *id)
+{
+	int pos = g_menu_find_section (menu, app_section_get_menu (section));
+	if (pos >= 0)
+		g_menu_remove (menu, pos);
+	g_action_muxer_remove (action_muxer, id);
+
+	g_signal_handlers_disconnect_by_func (section, actions_changed, NULL);
+	g_signal_handlers_disconnect_by_func (section, draws_attention_changed, NULL);
+	g_signal_handlers_disconnect_by_func (section, uses_chat_status_changed, NULL);
+	g_signal_handlers_disconnect_by_func (section, remove_section, NULL);
+
+	g_hash_table_remove (applications, id);
+}
+
 static AppSection *
 add_application (const gchar *desktop_id)
 {
@@ -167,6 +183,11 @@ add_application (const gchar *desktop_id)
 				  G_CALLBACK (draws_attention_changed), NULL);
 		g_signal_connect (section, "notify::uses-chat-status",
 				  G_CALLBACK (uses_chat_status_changed), NULL);
+		g_signal_connect_data (section, "destroy",
+				       G_CALLBACK (remove_section),
+				       g_strdup (id),
+				       (GClosureNotify) g_free,
+				       0);
 
 		/* TODO insert it at the right position (alphabetically by application name) */
 		menuitem = g_menu_item_new_section (NULL, app_section_get_menu (section));
@@ -197,20 +218,13 @@ remove_application (const char *desktop_id)
 
 	section = g_hash_table_lookup (applications, id);
 	if (section) {
-		int pos = g_menu_find_section (menu, app_section_get_menu (section));
-		if (pos >= 0)
-			g_menu_remove (menu, pos);
-		g_action_muxer_remove (action_muxer, id);
-
-		g_signal_handlers_disconnect_by_func (section, actions_changed, NULL);
-		g_signal_handlers_disconnect_by_func (section, draws_attention_changed, NULL);
-		g_signal_handlers_disconnect_by_func (section, uses_chat_status_changed, NULL);
+		remove_section (section, id);
 	}
 	else {
+		g_hash_table_remove (applications, id);
 		g_warning ("could not remove '%s', it's not registered", desktop_id);
 	}
 	
-	g_hash_table_remove (applications, id);
 	g_free (id);
 	g_object_unref (appinfo);
 }