[totem] Use the {video,audio,text}-tags-changed signals of playbin2

[Sebastian Dröge <sdroege src gnome org>]

commit b45f8e3aacc6c21ef3e50744ca63327c0e0f136a
Author: Sebastian Dröge <sebastian droege collabora co uk>
Date:   Mon Jun 8 12:16:30 2009 +0200

    Use the {video,audio,text}-tags-changed signals of playbin2
    
    2009-06-08  Sebastian Dröge  <sebastian droege collabora co uk>
    
            * src/backend/bacon-video-widget-gst-0.10.c:
            If we have playbin2 from gst-plugins-base 0.10.23.1 or newer use
            the new {audio,video,text}-tags-changed signals for noticing if
            tags have changed. This also gives us immediately the corresponding
            stream id and the type of the stream and makes it unnecessary to
            try to get the type via the tag messages' sender.
    
            This fixes bug #584689, prevents tags for unused streams to be
            displayed and makes sure that audio/video tags of a demuxer or
            other generic elements are used.
---
 ChangeLog                                 |   13 ++
 src/backend/bacon-video-widget-gst-0.10.c |  253 ++++++++++++++++++++++-------
 2 files changed, 211 insertions(+), 55 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index 9801c44..deffb3d 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,16 @@
+2009-06-08  Sebastian Dröge  <sebastian droege collabora co uk>
+
+	* src/backend/bacon-video-widget-gst-0.10.c:
+	If we have playbin2 from gst-plugins-base 0.10.23.1 or newer use
+	the new {audio,video,text}-tags-changed signals for noticing if
+	tags have changed. This also gives us immediately the corresponding
+	stream id and the type of the stream and makes it unnecessary to
+	try to get the type via the tag messages' sender.
+
+	This fixes bug #584689, prevents tags for unused streams to be
+	displayed and makes sure that audio/video tags of a demuxer or
+	other generic elements are used.
+
 2009-06-07  Sebastian Dröge  <sebastian droege collabora co uk>
 
 	* src/backend/bacon-video-widget-gst-0.10.c:
diff --git a/src/backend/bacon-video-widget-gst-0.10.c b/src/backend/bacon-video-widget-gst-0.10.c
index bd515dc..5a1462e 100644
--- a/src/backend/bacon-video-widget-gst-0.10.c
+++ b/src/backend/bacon-video-widget-gst-0.10.c
@@ -257,6 +257,12 @@ static int bvw_signals[LAST_SIGNAL] = { 0 };
 
 static GThread *gui_thread;
 
+/* FIXME: Remove this when we depend on gst-plugins-base >= 0.10.24
+ *
+ * TRUE if playbin2 from GIT with {audio,video,text}-tags-changed
+ * signals is found */
+static gboolean playbin2_tags_changed_signals = FALSE;
+
 GST_DEBUG_CATEGORY (_totem_gst_debug_cat);
 #define GST_CAT_DEFAULT _totem_gst_debug_cat
 
@@ -1519,6 +1525,147 @@ bvw_check_missing_plugins_on_preroll (BaconVideoWidget * bvw)
 }
 
 static void
+bvw_update_tags (BaconVideoWidget * bvw, GstTagList *tag_list, const gchar *type)
+{
+  GstTagList **cache = NULL;
+  GstTagList *result;
+
+  GST_DEBUG ("Tags: %" GST_PTR_FORMAT, tag_list);
+
+  /* all tags (replace previous tags, title/artist/etc. might change
+   * in the middle of a stream, e.g. with radio streams) */
+  result = gst_tag_list_merge (bvw->priv->tagcache, tag_list,
+                                   GST_TAG_MERGE_REPLACE);
+  if (bvw->priv->tagcache)
+    gst_tag_list_free (bvw->priv->tagcache);
+  bvw->priv->tagcache = result;
+
+  /* media-type-specific tags */
+  if (!strcmp (type, "video")) {
+    cache = &bvw->priv->videotags;
+  } else if (!strcmp (type, "audio")) {
+    cache = &bvw->priv->audiotags;
+  }
+
+  if (cache) {
+    result = gst_tag_list_merge (*cache, tag_list, GST_TAG_MERGE_REPLACE);
+    if (*cache)
+      gst_tag_list_free (*cache);
+    *cache = result;
+  }
+
+  /* clean up */
+  gst_tag_list_free (tag_list);
+
+  /* if we're not interactive, we want to announce metadata
+   * only later when we can be sure we got it all */
+  if (bvw->priv->use_type == BVW_USE_TYPE_VIDEO ||
+      bvw->priv->use_type == BVW_USE_TYPE_AUDIO) {
+      /* If we updated metadata and we have a new title, send it
+       * using TITLE_CHANGE, so that the UI knows it has a new
+       * streaming title */
+    GValue value = { 0, };
+    
+    g_signal_emit (bvw, bvw_signals[SIGNAL_GOT_METADATA], 0);
+
+    bacon_video_widget_get_metadata (bvw, BVW_INFO_TITLE, &value);
+    if (g_value_get_string (&value))
+      g_signal_emit (bvw, bvw_signals[SIGNAL_TITLE_CHANGE], 0, g_value_get_string (&value));
+    g_value_unset (&value);
+  }
+}
+
+typedef struct {
+  BaconVideoWidget *bvw;
+  GstTagList *tags;
+  const gchar *type;
+} UpdateTagsDelayedData;
+
+static gboolean
+bvw_update_tags_dispatcher (gpointer user_data)
+{
+  UpdateTagsDelayedData *data = user_data;
+
+  bvw_update_tags (data->bvw, data->tags, data->type);
+
+  g_object_unref (G_OBJECT (data->bvw));
+
+  g_free (data);
+
+  return FALSE;
+}
+
+/* Marshal the changed tags to the main thread for updating the GUI
+ * and sending the BVW signals */
+static void
+bvw_update_tags_delayed (BaconVideoWidget *bvw, GstTagList *tags, const gchar *type) {
+  UpdateTagsDelayedData *data = g_new0 (UpdateTagsDelayedData, 1);
+
+  data->bvw = g_object_ref (G_OBJECT (bvw));
+  data->tags = tags;
+  data->type = type;
+
+  g_idle_add (bvw_update_tags_dispatcher, data);
+}
+
+static void
+video_tags_changed_cb (GstElement *playbin2, gint stream_id, gpointer user_data)
+{
+  BaconVideoWidget *bvw = (BaconVideoWidget *) user_data;
+  GstTagList *tags = NULL;
+  gint current_stream_id = 0;
+
+  g_object_get (G_OBJECT (bvw->priv->play), "current-video", &current_stream_id, NULL);
+
+  /* Only get the updated tags if it's for our current stream id */
+  if (current_stream_id != stream_id)
+    return;
+
+  g_signal_emit_by_name (G_OBJECT (bvw->priv->play), "get-video-tags", stream_id, &tags);
+
+  if (tags)
+    bvw_update_tags_delayed (bvw, tags, "video");
+}
+
+static void
+audio_tags_changed_cb (GstElement *playbin2, gint stream_id, gpointer user_data)
+{
+  BaconVideoWidget *bvw = (BaconVideoWidget *) user_data;
+  GstTagList *tags = NULL;
+  gint current_stream_id = 0;
+
+  g_object_get (G_OBJECT (bvw->priv->play), "current-audio", &current_stream_id, NULL);
+
+  /* Only get the updated tags if it's for our current stream id */
+  if (current_stream_id != stream_id)
+    return;
+
+  g_signal_emit_by_name (G_OBJECT (bvw->priv->play), "get-audio-tags", stream_id, &tags);
+
+  if (tags)
+    bvw_update_tags_delayed (bvw, tags, "audio");
+}
+
+static void
+text_tags_changed_cb (GstElement *playbin2, gint stream_id, gpointer user_data)
+{
+  BaconVideoWidget *bvw = (BaconVideoWidget *) user_data;
+  GstTagList *tags = NULL;
+  gint current_stream_id = 0;
+
+  g_object_get (G_OBJECT (bvw->priv->play), "current-text", &current_stream_id, NULL);
+
+  /* Only get the updated tags if it's for our current stream id */
+  if (current_stream_id != stream_id)
+    return;
+
+  g_signal_emit_by_name (G_OBJECT (bvw->priv->play), "get-text-tags", stream_id, &tags);
+
+  if (tags)
+    bvw_update_tags_delayed (bvw, tags, "text");
+}
+
+static void
 bvw_bus_message_cb (GstBus * bus, GstMessage * message, gpointer data)
 {
   BaconVideoWidget *bvw = (BaconVideoWidget *) data;
@@ -1570,63 +1717,29 @@ bvw_bus_message_cb (GstBus * bus, GstMessage * message, gpointer data)
       GST_WARNING ("Warning message: %" GST_PTR_FORMAT, message);
       break;
     }
-    case GST_MESSAGE_TAG: {
-      GstTagList *tag_list, *result;
-      GstElementFactory *f;
-
-      gst_message_parse_tag (message, &tag_list);
-
-      GST_DEBUG ("Tags: %" GST_PTR_FORMAT, tag_list);
-
-      /* all tags (replace previous tags, title/artist/etc. might change
-       * in the middle of a stream, e.g. with radio streams) */
-      result = gst_tag_list_merge (bvw->priv->tagcache, tag_list,
-                                   GST_TAG_MERGE_REPLACE);
-      if (bvw->priv->tagcache)
-        gst_tag_list_free (bvw->priv->tagcache);
-      bvw->priv->tagcache = result;
-
-      /* media-type-specific tags */
-      if (GST_IS_ELEMENT (message->src) &&
-          (f = gst_element_get_factory (GST_ELEMENT (message->src)))) {
-        const gchar *klass = gst_element_factory_get_klass (f);
-        GstTagList **cache = NULL;
-
-        if (g_strrstr (klass, "Video")) {
-          cache = &bvw->priv->videotags;
-        } else if (g_strrstr (klass, "Audio")) {
-          cache = &bvw->priv->audiotags;
-        }
-
-        if (cache) {
-          result = gst_tag_list_merge (*cache, tag_list, GST_TAG_MERGE_REPLACE);
-          if (*cache)
-            gst_tag_list_free (*cache);
-          *cache = result;
-        }
-      }
-
-      /* clean up */
-      gst_tag_list_free (tag_list);
-
-      /* if we're not interactive, we want to announce metadata
-       * only later when we can be sure we got it all */
-      if (bvw->priv->use_type == BVW_USE_TYPE_VIDEO ||
-          bvw->priv->use_type == BVW_USE_TYPE_AUDIO) {
-	/* If we updated metadata and we have a new title, send it
- 	 * using TITLE_CHANGE, so that the UI knows it has a new
-	 * streaming title */
-	GValue value = { 0, };
-
-	g_signal_emit (bvw, bvw_signals[SIGNAL_GOT_METADATA], 0);
-
-	bacon_video_widget_get_metadata (bvw, BVW_INFO_TITLE, &value);
-	if (g_value_get_string (&value))
-	  g_signal_emit (bvw, bvw_signals[SIGNAL_TITLE_CHANGE], 0, g_value_get_string (&value));
-	g_value_unset (&value);
+    case GST_MESSAGE_TAG: 
+      /* If we get tags from the -tags-changed signals ignore the tag messages */
+      if (!playbin2_tags_changed_signals) {
+	GstTagList *taglist;
+	const gchar *type = "none";
+	GstElementFactory *f;
+	
+	gst_message_parse_tag (message, &taglist);
+
+        /* get stream type */
+        if (GST_IS_ELEMENT (message->src) &&
+            (f = gst_element_get_factory (GST_ELEMENT (message->src)))) {
+          const gchar *klass = gst_element_factory_get_klass (f);
+
+          if (g_strrstr (klass, "Video")) {
+            type = "video";
+          } else if (g_strrstr (klass, "Audio")) {
+            type = "audio";
+          }
+	}
+	bvw_update_tags (bvw, taglist, type);
       }
       break;
-    }
     case GST_MESSAGE_EOS:
       GST_DEBUG ("EOS message");
       /* update slider one last time */
@@ -2229,6 +2342,7 @@ bacon_video_widget_get_subtitle (BaconVideoWidget * bvw)
 void
 bacon_video_widget_set_subtitle (BaconVideoWidget * bvw, int subtitle)
 {
+  GstTagList *tags;
   gint flags;
 
   g_return_if_fail (bvw != NULL);
@@ -2245,6 +2359,13 @@ bacon_video_widget_set_subtitle (BaconVideoWidget * bvw, int subtitle)
   }
   
   g_object_set (bvw->priv->play, "flags", flags, "current-text", subtitle, NULL);
+  
+  if (flags & GST_PLAY_FLAGS_TEXT) {
+    g_object_get (bvw->priv->play, "current-text", &subtitle, NULL);
+
+    g_signal_emit_by_name (G_OBJECT (bvw->priv->play), "get-text-tags", subtitle, &tags);
+    bvw_update_tags (bvw, tags, "text");
+  }
 }
 
 /**
@@ -2446,6 +2567,8 @@ bacon_video_widget_get_language (BaconVideoWidget * bvw)
 void
 bacon_video_widget_set_language (BaconVideoWidget * bvw, int language)
 {
+  GstTagList *tags;
+
   g_return_if_fail (bvw != NULL);
   g_return_if_fail (BACON_IS_VIDEO_WIDGET (bvw));
   g_return_if_fail (bvw->priv->play != NULL);
@@ -2462,6 +2585,9 @@ bacon_video_widget_set_language (BaconVideoWidget * bvw, int language)
   g_object_get (bvw->priv->play, "current-audio", &language, NULL);
   GST_DEBUG ("current-audio now: %d", language);
 
+  g_signal_emit_by_name (G_OBJECT (bvw->priv->play), "get-audio-tags", language, &tags);
+  bvw_update_tags (bvw, tags, "audio");
+
   /* so it updates its metadata for the newly-selected stream */
   g_signal_emit (bvw, bvw_signals[SIGNAL_GOT_METADATA], 0, NULL);
   g_signal_emit (bvw, bvw_signals[SIGNAL_CHANNELS_CHANGE], 0);
@@ -5572,6 +5698,12 @@ cb_gconf (GConfClient * client,
 
 G_DEFINE_TYPE(BaconVideoWidget, bacon_video_widget, GTK_TYPE_EVENT_BOX)
 
+static void check_playbin2_version (GstElement *playbin2)
+{
+  if (g_signal_lookup ("audio-tags-changed", G_TYPE_FROM_INSTANCE (playbin2)))
+    playbin2_tags_changed_signals = TRUE;
+}
+
 /* applications must use exactly one of bacon_video_widget_get_option_group()
  * OR bacon_video_widget_init_backend(), but not both */
 
@@ -6127,6 +6259,17 @@ bacon_video_widget_new (int width, int height,
   g_signal_connect (bvw->priv->play, "text-changed",
       G_CALLBACK (playbin_stream_changed_cb), bvw);
 
+  /* Check if we have playbin2 with the -tags-changed signals */
+  check_playbin2_version (bvw->priv->play);
+  if (playbin2_tags_changed_signals) {
+    g_signal_connect (bvw->priv->play, "video-tags-changed",
+        G_CALLBACK (video_tags_changed_cb), bvw);
+    g_signal_connect (bvw->priv->play, "audio-tags-changed",
+        G_CALLBACK (audio_tags_changed_cb), bvw);
+    g_signal_connect (bvw->priv->play, "text-tags-changed",
+        G_CALLBACK (text_tags_changed_cb), bvw);
+  }
+
   /* assume we're always called from the main Gtk+ GUI thread */
   gui_thread = g_thread_self();