[nautilus] canvas-container: pre-compute selection

[Cosimo Cecchi <cosimoc src gnome org>]

commit 01bea94ea3b002de90c791a99d5e6894d4d512d1
Author: Cosimo Cecchi <cosimoc gnome org>
Date:   Sat Aug 30 19:23:59 2014 -0700

    canvas-container: pre-compute selection
    
    There's no need to always iterate over the list of icons in order to get
    the selection - just keep a separate sorted list.

 libnautilus-private/nautilus-canvas-container.c |   45 +++++++++++++++++------
 libnautilus-private/nautilus-canvas-private.h   |    2 +
 2 files changed, 36 insertions(+), 11 deletions(-)
---
diff --git a/libnautilus-private/nautilus-canvas-container.c b/libnautilus-private/nautilus-canvas-container.c
index d693288..707a194 100644
--- a/libnautilus-private/nautilus-canvas-container.c
+++ b/libnautilus-private/nautilus-canvas-container.c
@@ -424,6 +424,13 @@ icon_toggle_selected (NautilusCanvasContainer *container,
        end_renaming_mode (container, TRUE);
 
        icon->is_selected = !icon->is_selected;
+       if (icon->is_selected) {
+               container->details->selection = g_list_prepend (container->details->selection, icon->data);
+               container->details->selection_needs_resort = TRUE;
+       } else {
+               container->details->selection = g_list_remove (container->details->selection, icon->data);
+       }
+
        eel_canvas_item_set (EEL_CANVAS_ITEM (icon->item),
                             "highlighted_for_selection", (gboolean) icon->is_selected,
                             NULL);
@@ -1096,6 +1103,19 @@ nautilus_canvas_container_update_scroll_region (NautilusCanvasContainer *contain
 }
 
 static int
+compare_icons_data (gconstpointer a, gconstpointer b, gpointer canvas_container)
+{
+       NautilusCanvasContainerClass *klass;
+       NautilusCanvasIconData *data_a, *data_b;
+
+       data_a = (NautilusCanvasIconData *) a;
+       data_b = (NautilusCanvasIconData *) b;
+       klass  = NAUTILUS_CANVAS_CONTAINER_GET_CLASS (canvas_container);
+
+       return klass->compare_icons (canvas_container, data_a, data_b);
+}
+
+static int
 compare_icons (gconstpointer a, gconstpointer b, gpointer canvas_container)
 {
        NautilusCanvasContainerClass *klass;
@@ -1109,6 +1129,15 @@ compare_icons (gconstpointer a, gconstpointer b, gpointer canvas_container)
 }
 
 static void
+sort_selection (NautilusCanvasContainer *container)
+{
+       container->details->selection = g_list_sort_with_data (container->details->selection,
+                                                              compare_icons_data,
+                                                              container);
+       container->details->selection_needs_resort = FALSE;
+}
+
+static void
 sort_icons (NautilusCanvasContainer *container,
              GList                **icons)
 {
@@ -1124,6 +1153,7 @@ static void
 resort (NautilusCanvasContainer *container)
 {
        sort_icons (container, &container->details->icons);
+       sort_selection (container);
 }
 
 typedef struct {
@@ -5636,6 +5666,7 @@ icon_destroy (NautilusCanvasContainer *container,
  
        details->icons = g_list_remove (details->icons, icon);
        details->new_icons = g_list_remove (details->new_icons, icon);
+       details->selection = g_list_remove (details->selection, icon->data);
        g_hash_table_remove (details->icon_set, icon->data);
 
        was_selected = icon->is_selected;
@@ -6360,21 +6391,13 @@ nautilus_canvas_container_reveal (NautilusCanvasContainer *container, NautilusCa
 GList *
 nautilus_canvas_container_get_selection (NautilusCanvasContainer *container)
 {
-       GList *list, *p;
-
        g_return_val_if_fail (NAUTILUS_IS_CANVAS_CONTAINER (container), NULL);
 
-       list = NULL;
-       for (p = container->details->icons; p != NULL; p = p->next) {
-               NautilusCanvasIcon *icon;
-
-               icon = p->data;
-               if (icon->is_selected) {
-                       list = g_list_prepend (list, icon->data);
-               }
+       if (container->details->selection_needs_resort) {
+               sort_selection (container);
        }
 
-       return g_list_reverse (list);
+       return g_list_copy (container->details->selection);
 }
 
 static GList *
diff --git a/libnautilus-private/nautilus-canvas-private.h b/libnautilus-private/nautilus-canvas-private.h
index b919529..bfccf19 100644
--- a/libnautilus-private/nautilus-canvas-private.h
+++ b/libnautilus-private/nautilus-canvas-private.h
@@ -118,6 +118,7 @@ struct NautilusCanvasContainerDetails {
        /* List of icons. */
        GList *icons;
        GList *new_icons;
+       GList *selection;
        GHashTable *icon_set;
 
        /* Current icon for keyboard navigation. */
@@ -243,6 +244,7 @@ struct NautilusCanvasContainerDetails {
 
        eel_boolean_bit is_loading : 1;
        eel_boolean_bit needs_resort : 1;
+       eel_boolean_bit selection_needs_resort : 1;
 
        eel_boolean_bit store_layout_timestamps : 1;
        eel_boolean_bit store_layout_timestamps_when_finishing_new_icons : 1;