[gthumb/ext: 30/79] update the thumbnail only if the file didn't change recently

[Paolo Bacchilega <paobac src gnome org>]

commit d046ca071095735992c7b8da11018e316b380cac
Author: Paolo Bacchilega <paobac src gnome org>
Date:   Tue Jun 30 00:55:02 2009 +0200

    update the thumbnail only if the file didn't change recently
    
    do not update the file each time a file_changed signal is emitted
    to avoid  excessive file reloads

 gthumb/gth-file-list.c       |   49 +++++++++++++++++++++++++++++++++++++++--
 gthumb/gth-file-list.h       |    2 +-
 gthumb/gth-file-source-vfs.c |    2 +-
 gthumb/gth-thumb-loader.c    |   24 ++------------------
 4 files changed, 51 insertions(+), 26 deletions(-)
---
diff --git a/gthumb/gth-file-list.c b/gthumb/gth-file-list.c
index a150d2c..e053604 100644
--- a/gthumb/gth-file-list.c
+++ b/gthumb/gth-file-list.c
@@ -99,6 +99,7 @@ struct _GthFileListPrivateData
 	gboolean         cancel;
 	gboolean         dirty;
 	guint            dirty_event;
+	guint            restart_thumb_update;
 	GList           *queue; /* list of GthFileListOp */
 	GtkCellRenderer *thumbnail_renderer;
 	GtkCellRenderer *text_renderer;
@@ -162,6 +163,11 @@ _gth_file_list_clear_queue (GthFileList *file_list)
 		file_list->priv->dirty = FALSE;
 	}
 
+	if (file_list->priv->restart_thumb_update != 0) {
+		g_source_remove (file_list->priv->restart_thumb_update);
+		file_list->priv->restart_thumb_update = 0;
+	}
+
 	g_list_foreach (file_list->priv->queue, (GFunc) gth_file_list_op_free, NULL);
 	g_list_free (file_list->priv->queue);
 	file_list->priv->queue = NULL;
@@ -1056,6 +1062,36 @@ update_thumbs_stopped (gpointer callback_data)
 }
 
 
+static gboolean
+restart_thumb_update_cb (gpointer data)
+{
+	GthFileList *file_list = data;
+
+	g_source_remove (file_list->priv->restart_thumb_update);
+	file_list->priv->restart_thumb_update = 0;
+
+	if (file_list->priv->queue == NULL)
+		_gth_file_list_update_next_thumb (file_list);
+
+	return FALSE;
+}
+
+
+static gboolean
+can_create_file_thumbnail (GthFileData *file_data,
+			   GTimeVal    *current_time,
+			   gboolean    *young_file_found)
+{
+	gboolean young_file;
+
+	young_file = (current_time->tv_sec - gth_file_data_get_mtime (file_data)) <= 1;
+	if (young_file)
+		*young_file_found = TRUE;
+
+	return ! file_data->error && ! young_file;
+}
+
+
 static void
 _gth_file_list_update_next_thumb (GthFileList *file_list)
 {
@@ -1067,6 +1103,8 @@ _gth_file_list_update_next_thumb (GthFileList *file_list)
 	GthFileData  *fd = NULL;
 	GList        *list, *scan;
 	int           new_pos = -1;
+	GTimeVal      current_time;
+	gboolean      young_file_found = FALSE;
 
 	if (file_list->priv->cancel || (file_list->priv->queue != NULL)) {
 		g_idle_add (update_thumbs_stopped, file_list);
@@ -1098,9 +1136,11 @@ _gth_file_list_update_next_thumb (GthFileList *file_list)
 
 	/* Find a not loaded thumbnail among the visible images. */
 
+	g_get_current_time (&current_time);
+
 	while (pos <= last_pos) {
 		fd = scan->data;
-		if (! fd->thumb_loaded && ! fd->error) {
+		if (! fd->thumb_loaded && can_create_file_thumbnail (fd, &current_time, &young_file_found)) {
 			new_pos = pos;
 			break;
 		}
@@ -1121,7 +1161,7 @@ _gth_file_list_update_next_thumb (GthFileList *file_list)
 			scan = g_list_nth (list, pos);
 			while (scan && ((pos - last_pos) <= N_LOOKAHEAD)) {
 				fd = scan->data;
-				if (! fd->thumb_created && ! fd->error) {
+				if (! fd->thumb_created && can_create_file_thumbnail (fd, &current_time, &young_file_found)) {
 					new_pos = pos;
 					break;
 				}
@@ -1138,7 +1178,7 @@ _gth_file_list_update_next_thumb (GthFileList *file_list)
 			scan = g_list_nth (list, pos);
 			while (scan && ((first_pos - pos) <= N_LOOKAHEAD)) {
 				fd = scan->data;
-				if (! fd->thumb_created && ! fd->error) {
+				if (! fd->thumb_created && can_create_file_thumbnail (fd, &current_time, &young_file_found)) {
 					new_pos = pos;
 					break;
 				}
@@ -1155,12 +1195,15 @@ _gth_file_list_update_next_thumb (GthFileList *file_list)
 
 	if (new_pos == -1) {
 		_gth_file_list_thumbs_completed (file_list);
+		if (young_file_found && (file_list->priv->restart_thumb_update == 0))
+			file_list->priv->restart_thumb_update = g_timeout_add (1500, restart_thumb_update_cb, file_list);
 		return;
 	}
 
 	/* We create thumbnail files for all images in the folder, but we only
 	   load the visible ones (and N_LOOKAHEAD before and N_LOOKAHEAD after the visible range),
 	   to minimize memory consumption in large folders. */
+
 	file_list->priv->update_thumb_in_view = (new_pos >= (first_pos - N_LOOKAHEAD)) &&
 						(new_pos <= (last_pos + N_LOOKAHEAD));
 	file_list->priv->thumb_pos = new_pos;
diff --git a/gthumb/gth-file-list.h b/gthumb/gth-file-list.h
index 222ccc2..cca125f 100644
--- a/gthumb/gth-file-list.h
+++ b/gthumb/gth-file-list.h
@@ -76,7 +76,7 @@ void           gth_file_list_set_sort_func  (GthFileList          *file_list,
 					     gboolean              inverse_sort);
 void           gth_file_list_enable_thumbs  (GthFileList          *file_list,
 					     gboolean              enable);
-void           gth_file_list_set_thumb_size (GthFileList         *file_list,
+void           gth_file_list_set_thumb_size (GthFileList          *file_list,
 					     int                   size);
 GtkWidget *    gth_file_list_get_view       (GthFileList          *file_list);
 int            gth_file_list_first_file     (GthFileList          *file_list,
diff --git a/gthumb/gth-file-source-vfs.c b/gthumb/gth-file-source-vfs.c
index f9352ad..97f2ade 100644
--- a/gthumb/gth-file-source-vfs.c
+++ b/gthumb/gth-file-source-vfs.c
@@ -34,7 +34,7 @@
 
 #define GTH_MONITOR_N_EVENTS 3
 #define MONITOR_UPDATE_DELAY 500
-#define DEBUG_MONITOR 1
+#undef DEBUG_MONITOR
 
 struct _GthFileSourceVfsPrivate
 {
diff --git a/gthumb/gth-thumb-loader.c b/gthumb/gth-thumb-loader.c
index 0baa2c7..1525f2f 100644
--- a/gthumb/gth-thumb-loader.c
+++ b/gthumb/gth-thumb-loader.c
@@ -45,7 +45,7 @@
 #define THUMBNAIL_LARGE_SIZE	  256
 #define THUMBNAIL_NORMAL_SIZE	  128
 #define THUMBNAIL_DIR_PERMISSIONS 0700
-#define KILL_THUMBNAILER_DELAY    3000
+#define MAX_THUMBNAILER_LIFETIME  2000   /* kill the thumbnailer after this amount of time*/
 
 struct _GthThumbLoaderPrivateData
 {
@@ -468,7 +468,7 @@ image_loader_ready_cb (GthImageLoader *iloader,
 		tloader->priv->thumbnailer_watch = g_child_watch_add (tloader->priv->thumbnailer_pid,
 								      watch_thumbnailer_cb,
 								      tloader);
-		tloader->priv->thumbnailer_timeout = g_timeout_add (KILL_THUMBNAILER_DELAY,
+		tloader->priv->thumbnailer_timeout = g_timeout_add (MAX_THUMBNAILER_LIFETIME,
 								    kill_thumbnailer_cb,
 								    tloader);
 	}
@@ -671,34 +671,16 @@ gth_thumb_loader_load__step2 (GthThumbLoader *tloader)
 
 	g_return_if_fail (tloader != NULL);
 
-	/*if ((tloader->priv->file == NULL) || ! gth_file_data_is_readable (tloader->priv->file)) {
-		g_signal_emit (G_OBJECT (tloader),
-			       gth_thumb_loader_signals[READY],
-			       0,
-			       g_error_new_literal (GTHUMB_ERROR, 0, "cannot read the file"));
-		return;
-	}*/
-
 	if (tloader->priv->use_cache) {
 		char   *uri;
 		time_t  mtime;
 
 		uri = g_file_get_uri (tloader->priv->file->file);
 		mtime = gth_file_data_get_mtime (tloader->priv->file);
-
 		cache_path = gnome_desktop_thumbnail_factory_lookup (tloader->priv->thumb_factory, uri, mtime);
-
-/*debug (DEBUG_INFO, "thumbnail for %s: %s\n", uri, cache_path); FIXME: delete when done */
-
 		if ((cache_path == NULL)
-		    && gnome_desktop_thumbnail_factory_has_valid_failed_thumbnail (tloader->priv->thumb_factory, uri, mtime)
-		    && ((time (NULL) - mtime) > (time_t) 5))
+		    && gnome_desktop_thumbnail_factory_has_valid_failed_thumbnail (tloader->priv->thumb_factory, uri, mtime))
 		{
-			/* Use the existing "failed" thumbnail, if it is over
-			   5 seconds old. Otherwise, try to thumbnail it again.
-			   The minimum age requirement addresses bug 432759,
-			   which occurs when a device like a scanner saves a file
-			   slowly in chunks. */
 			g_signal_emit (G_OBJECT (tloader),
 				       gth_thumb_loader_signals[READY],
 				       0,