[gnome-photos/wip/rishi/collections] view-model: Stop listening to info-updated when an item is removed

[Debarshi Ray <debarshir src gnome org>]

commit a9ec1024b1f208f151bdae33ccd08352c6595600
Author: Debarshi Ray <debarshir gnome org>
Date:   Tue Oct 6 19:40:03 2015 +0200

    view-model: Stop listening to info-updated when an item is removed
    
    Items that have been removed from ItemManager can still emit the
    signal due to any ongoing thumbnailing operation. This can cause
    ViewModel to erroneously re-add an item that is supposed to have been
    removed.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=756133

 src/photos-view-model.c |   43 +++++++++++++++++++++++++++++++++++++++++--
 1 files changed, 41 insertions(+), 2 deletions(-)
---
diff --git a/src/photos-view-model.c b/src/photos-view-model.c
index 2de9f91..8234102 100644
--- a/src/photos-view-model.c
+++ b/src/photos-view-model.c
@@ -47,6 +47,7 @@
 
 struct _PhotosViewModelPrivate
 {
+  GHashTable *info_updated_ids;
   PhotosBaseManager *item_mngr;
   PhotosModeController *mode_cntrlr;
   PhotosOffsetController *offset_cntrlr;
@@ -218,6 +219,8 @@ photos_view_model_object_removed (PhotosViewModel *self, GObject *object)
 {
   PhotosViewModelPrivate *priv = self->priv;
   PhotosBaseItem *item = PHOTOS_BASE_ITEM (object);
+  const gchar *id;
+  gpointer data;
 
   /* Update the count so that PhotosOffsetController has the correct
    * values. Otherwise things like loading more items and "No
@@ -228,6 +231,21 @@ photos_view_model_object_removed (PhotosViewModel *self, GObject *object)
   priv->oldest_mtime = G_MAXINT64;
   gtk_tree_model_foreach (GTK_TREE_MODEL (self), photos_view_model_item_removed_foreach, item);
   g_object_set_data (object, priv->row_ref_key, NULL);
+
+  id = photos_filterable_get_id (PHOTOS_FILTERABLE (item));
+  data = g_hash_table_lookup (priv->info_updated_ids, id);
+  if (data == NULL)
+    {
+      g_critical ("Failed to find info-updated signal handler ID for %s", id);
+    }
+  else
+    {
+      guint info_updated_id;
+
+      info_updated_id = GPOINTER_TO_UINT (data);
+      g_signal_handler_disconnect (item, (gulong) info_updated_id);
+      g_hash_table_remove (priv->info_updated_ids, id);
+    }
 }
 
 
@@ -299,11 +317,23 @@ photos_view_model_object_added (PhotosViewModel *self, GObject *object)
   GtkTreeRowReference *row_ref;
   gboolean is_collection;
   gboolean is_favorite;
+  const gchar *id;
+  gpointer data;
+  guint info_updated_id;
 
   row_ref = (GtkTreeRowReference *) g_object_get_data (G_OBJECT (item), priv->row_ref_key);
   if (row_ref != NULL)
     return;
 
+  id = photos_filterable_get_id (PHOTOS_FILTERABLE (item));
+  data = g_hash_table_lookup (priv->info_updated_ids, id);
+  if (data != NULL)
+    {
+      info_updated_id = GPOINTER_TO_UINT (data);
+      g_signal_handler_disconnect (item, (gulong) info_updated_id);
+      g_hash_table_remove (priv->info_updated_ids, id);
+    }
+
   active_collection = photos_item_manager_get_active_collection (PHOTOS_ITEM_MANAGER (priv->item_mngr));
   is_collection = photos_base_item_is_collection (item);
   is_favorite = photos_base_item_is_favorite (item);
@@ -320,7 +350,12 @@ photos_view_model_object_added (PhotosViewModel *self, GObject *object)
   photos_view_model_add_item (self, item);
 
  out:
-  g_signal_connect_object (item, "info-updated", G_CALLBACK (photos_view_model_info_updated), self, 0);
+  info_updated_id = (guint) g_signal_connect_object (item,
+                                                     "info-updated",
+                                                     G_CALLBACK (photos_view_model_info_updated),
+                                                     self,
+                                                     0);
+  g_hash_table_insert (priv->info_updated_ids, g_strdup (id), GUINT_TO_POINTER (info_updated_id));
 }
 
 
@@ -415,8 +450,10 @@ static void
 photos_view_model_finalize (GObject *object)
 {
   PhotosViewModel *self = PHOTOS_VIEW_MODEL (object);
+  PhotosViewModelPrivate *priv = self->priv;
 
-  g_free (self->priv->row_ref_key);
+  g_hash_table_unref (priv->info_updated_ids);
+  g_free (priv->row_ref_key);
 
   G_OBJECT_CLASS (photos_view_model_parent_class)->finalize (object);
 }
@@ -466,6 +503,8 @@ photos_view_model_init (PhotosViewModel *self)
   gtk_list_store_set_column_types (GTK_LIST_STORE (self), sizeof (columns) / sizeof (columns[0]), columns);
   gtk_tree_sortable_set_sort_column_id (GTK_TREE_SORTABLE (self), PHOTOS_VIEW_MODEL_MTIME, 
GTK_SORT_DESCENDING);
 
+  priv->info_updated_ids = g_hash_table_new_full (g_str_hash, g_str_equal, g_free, NULL);
+
   priv->item_mngr = g_object_ref (state->item_mngr);
   priv->mode_cntrlr = photos_mode_controller_dup_singleton ();