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

[Debarshi Ray <debarshir src gnome org>]

commit 3db5a72c69ec2403c1f4d38f014e513a97cbc835
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 or update an item that is supposed to
    have been removed.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=756133

 src/photos-view-model.c |   59 ++++++++++++++++++++++++++++++++++++++++------
 1 files changed, 51 insertions(+), 8 deletions(-)
---
diff --git a/src/photos-view-model.c b/src/photos-view-model.c
index c708e0a..537d49e 100644
--- a/src/photos-view-model.c
+++ b/src/photos-view-model.c
@@ -45,6 +45,7 @@
 
 struct _PhotosViewModelPrivate
 {
+  GHashTable *info_updated_ids;
   PhotosBaseManager *item_mngr;
   PhotosModeController *mode_cntrlr;
   PhotosOffsetController *offset_cntrlr;
@@ -212,10 +213,9 @@ photos_view_model_item_removed_foreach (GtkTreeModel *model,
 
 
 static void
-photos_view_model_object_removed (PhotosViewModel *self, GObject *object)
+photos_view_model_remove_item (PhotosViewModel *self, PhotosBaseItem *item)
 {
   PhotosViewModelPrivate *priv = self->priv;
-  PhotosBaseItem *item = PHOTOS_BASE_ITEM (object);
 
   /* Update the count so that PhotosOffsetController has the correct
    * values. Otherwise things like loading more items and "No
@@ -225,7 +225,7 @@ 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);
+  g_object_set_data (G_OBJECT (item), priv->row_ref_key, NULL);
 }
 
 
@@ -248,7 +248,7 @@ photos_view_model_info_updated (PhotosBaseItem *item, gpointer user_data)
 
       is_collection = photos_base_item_is_collection (item);
       if (!is_collection && row_ref != NULL && active_collection == NULL)
-        photos_view_model_object_removed (self, G_OBJECT (item));
+        photos_view_model_remove_item (self, item);
       else if (is_collection  && row_ref == NULL && active_collection == NULL)
         photos_view_model_add_item (self, item);
     }
@@ -258,7 +258,7 @@ photos_view_model_info_updated (PhotosBaseItem *item, gpointer user_data)
 
       is_favorite = photos_base_item_is_favorite (item);
       if (!is_favorite && row_ref != NULL && active_collection == NULL)
-        photos_view_model_object_removed (self, G_OBJECT (item));
+        photos_view_model_remove_item (self, item);
       else if (is_favorite  && row_ref == NULL && active_collection == NULL)
         photos_view_model_add_item (self, item);
     }
@@ -268,7 +268,7 @@ photos_view_model_info_updated (PhotosBaseItem *item, gpointer user_data)
 
       is_collection = photos_base_item_is_collection (item);
       if (is_collection && row_ref != NULL)
-        photos_view_model_object_removed (self, G_OBJECT (item));
+        photos_view_model_remove_item (self, item);
       else if (!is_collection  && row_ref == NULL)
         photos_view_model_add_item (self, item);
     }
@@ -297,11 +297,23 @@ 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);
@@ -318,7 +330,34 @@ 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));
+}
+
+
+static void
+photos_view_model_object_removed (PhotosViewModel *self, GObject *object)
+{
+  PhotosViewModelPrivate *priv = self->priv;
+  PhotosBaseItem *item = PHOTOS_BASE_ITEM (object);
+  const gchar *id;
+  gpointer data;
+  guint info_updated_id;
+
+  photos_view_model_remove_item (self, item);
+
+  id = photos_filterable_get_id (PHOTOS_FILTERABLE (item));
+  data = g_hash_table_lookup (priv->info_updated_ids, id);
+
+  g_return_if_fail (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);
 }
 
 
@@ -413,8 +452,10 @@ 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);
 }
@@ -464,6 +505,8 @@ 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 = g_object_ref (state->mode_cntrlr);