[nautilus] Switch location on canvas view hover

[William Jon McCann <mccann src gnome org>]

commit 161b8424b59f66aad527ce47827bca74bf850f81
Author: William Jon McCann <jmccann redhat com>
Date:   Sat Jan 19 14:49:20 2013 -0500

    Switch location on canvas view hover
    
    https://bugzilla.gnome.org/show_bug.cgi?id=692097

 libnautilus-private/nautilus-canvas-container.c |   11 ++++
 libnautilus-private/nautilus-canvas-container.h |    2 +
 libnautilus-private/nautilus-canvas-dnd.c       |   66 +++++++++++++++++++++++
 libnautilus-private/nautilus-canvas-dnd.h       |    4 +-
 src/nautilus-canvas-view.c                      |   10 ++++
 5 files changed, 92 insertions(+), 1 deletions(-)
---
diff --git a/libnautilus-private/nautilus-canvas-container.c b/libnautilus-private/nautilus-canvas-container.c
index 3fffae5..8024962 100644
--- a/libnautilus-private/nautilus-canvas-container.c
+++ b/libnautilus-private/nautilus-canvas-container.c
@@ -241,6 +241,7 @@ enum {
 	HANDLE_URI_LIST,
 	HANDLE_TEXT,
 	HANDLE_RAW,
+	HANDLE_HOVER,
 	SELECTION_CHANGED,
 	ICON_ADDED,
 	ICON_REMOVED,
@@ -4935,6 +4936,16 @@ nautilus_canvas_container_class_init (NautilusCanvasContainerClass *class)
 				GDK_TYPE_DRAG_ACTION,
 				G_TYPE_INT,
 				G_TYPE_INT);
+	signals[HANDLE_HOVER] =
+		g_signal_new ("handle_hover",
+			      G_TYPE_FROM_CLASS (class),
+			      G_SIGNAL_RUN_LAST,
+			      G_STRUCT_OFFSET (NautilusCanvasContainerClass,
+					       handle_hover),
+			      NULL, NULL,
+			      g_cclosure_marshal_generic,
+			      G_TYPE_NONE, 1,
+			      G_TYPE_STRING);
 	signals[GET_CONTAINER_URI] 
 		= g_signal_new ("get_container_uri",
 		                G_TYPE_FROM_CLASS (class),
diff --git a/libnautilus-private/nautilus-canvas-container.h b/libnautilus-private/nautilus-canvas-container.h
index 5ad6d52..d5ec7a0 100644
--- a/libnautilus-private/nautilus-canvas-container.h
+++ b/libnautilus-private/nautilus-canvas-container.h
@@ -123,6 +123,8 @@ typedef struct {
 						   GdkDragAction action,
 						   int x,
 						   int y);
+	void	     (* handle_hover)		  (NautilusCanvasContainer *container,
+						   const char *target_uri);
 
 	/* Queries on the container for subclass/client.
 	 * These must be implemented. The default "do nothing" is not good enough.
diff --git a/libnautilus-private/nautilus-canvas-dnd.c b/libnautilus-private/nautilus-canvas-dnd.c
index 5329d9b..efa71d8 100644
--- a/libnautilus-private/nautilus-canvas-dnd.c
+++ b/libnautilus-private/nautilus-canvas-dnd.c
@@ -1243,6 +1243,15 @@ nautilus_canvas_dnd_update_drop_target (NautilusCanvasContainer *container,
 }
 
 static void
+remove_hover_timer (NautilusCanvasDndInfo *dnd_info)
+{
+	if (dnd_info->hover_id != 0) {
+		g_source_remove (dnd_info->hover_id);
+		dnd_info->hover_id = 0;
+	}
+}
+
+static void
 nautilus_canvas_container_free_drag_data (NautilusCanvasContainer *container)
 {
 	NautilusCanvasDndInfo *dnd_info;
@@ -1265,6 +1274,11 @@ nautilus_canvas_container_free_drag_data (NautilusCanvasContainer *container)
 		g_free (dnd_info->drag_info.direct_save_uri);
 		dnd_info->drag_info.direct_save_uri = NULL;
 	}
+
+	g_free (dnd_info->target_uri);
+	dnd_info->target_uri = NULL;
+
+	remove_hover_timer (dnd_info);
 }
 
 static void
@@ -1456,6 +1470,51 @@ stop_dnd_highlight (GtkWidget *widget)
 }
 
 static gboolean
+hover_timer (gpointer user_data)
+{
+	NautilusCanvasContainer *container = user_data;
+	NautilusCanvasDndInfo *dnd_info;
+
+	dnd_info = container->details->dnd_info;
+
+	dnd_info->hover_id = 0;
+
+	g_signal_emit_by_name (container, "handle_hover", dnd_info->target_uri);
+
+	return FALSE;
+}
+
+static void
+check_hover_timer (NautilusCanvasContainer *container,
+		   const char              *uri)
+{
+	NautilusCanvasDndInfo *dnd_info;
+	GtkSettings *settings;
+	guint timeout;
+
+	dnd_info = container->details->dnd_info;
+
+	if (g_strcmp0 (uri, dnd_info->target_uri) == 0) {
+		return;
+	}
+	remove_hover_timer (dnd_info);
+
+	settings = gtk_widget_get_settings (GTK_WIDGET (container));
+	g_object_get (settings, "gtk-timeout-expand", &timeout, NULL);
+
+	g_free (dnd_info->target_uri);
+	dnd_info->target_uri = NULL;
+
+	if (uri != NULL) {
+		dnd_info->target_uri = g_strdup (uri);
+		dnd_info->hover_id =
+			gdk_threads_add_timeout (timeout,
+						 hover_timer,
+						 container);
+	}
+}
+
+static gboolean
 drag_motion_callback (GtkWidget *widget,
 		      GdkDragContext *context,
 		      int x, int y,
@@ -1474,7 +1533,14 @@ drag_motion_callback (GtkWidget *widget,
 	nautilus_canvas_container_get_drop_action (NAUTILUS_CANVAS_CONTAINER (widget), context, x, y,
 						 &action);
 	if (action != 0) {
+		char *uri;
+		uri = nautilus_canvas_container_find_drop_target (NAUTILUS_CANVAS_CONTAINER (widget),
+								  context, x, y, NULL, TRUE);
+		check_hover_timer (NAUTILUS_CANVAS_CONTAINER (widget), uri);
+		g_free (uri);
 		start_dnd_highlight (widget);
+	} else {
+		remove_hover_timer (NAUTILUS_CANVAS_CONTAINER (widget)->details->dnd_info);
 	}
 	  
 	gdk_drag_status (context, action, time);
diff --git a/libnautilus-private/nautilus-canvas-dnd.h b/libnautilus-private/nautilus-canvas-dnd.h
index 00d8719..f7068b0 100644
--- a/libnautilus-private/nautilus-canvas-dnd.h
+++ b/libnautilus-private/nautilus-canvas-dnd.h
@@ -37,9 +37,11 @@ typedef struct {
 	NautilusDragInfo drag_info;
 
 	gboolean highlighted;
-	
+	char *target_uri;
+
 	/* Shadow for the icons being dragged.  */
 	EelCanvasItem *shadow;
+	guint hover_id;
 } NautilusCanvasDndInfo;
 
 
diff --git a/src/nautilus-canvas-view.c b/src/nautilus-canvas-view.c
index cc5e0e1..e25d327 100644
--- a/src/nautilus-canvas-view.c
+++ b/src/nautilus-canvas-view.c
@@ -2007,6 +2007,14 @@ canvas_view_handle_raw (NautilusCanvasContainer *container, const char *raw_data
 				       raw_data, length, target_uri, direct_save_uri, action, x, y);
 }
 
+static void
+canvas_view_handle_hover (NautilusCanvasContainer *container,
+			  const char *target_uri,
+			  NautilusCanvasView *view)
+{
+	nautilus_view_handle_hover (NAUTILUS_VIEW (view), target_uri);
+}
+
 static char *
 canvas_view_get_first_visible_file (NautilusView *view)
 {
@@ -2228,6 +2236,8 @@ nautilus_canvas_view_init (NautilusCanvasView *canvas_view)
 				 G_CALLBACK (canvas_view_handle_text), canvas_view, 0);
 	g_signal_connect_object (canvas_container, "handle_raw",
 				 G_CALLBACK (canvas_view_handle_raw), canvas_view, 0);
+	g_signal_connect_object (canvas_container, "handle_hover",
+				 G_CALLBACK (canvas_view_handle_hover), canvas_view, 0);
 
 	canvas_view->details->clipboard_handler_id =
 		g_signal_connect (nautilus_clipboard_monitor_get (),