[pitivi] Serialize seek actions and fix state change action serialization

[Thibault Saunier <tsaunier src gnome org>]

commit d74c0e8d4d497d35d26e991beb437e8ac33bf484
Author: Thibault Saunier <tsaunier gnome org>
Date:   Thu Sep 25 12:17:12 2014 +0200

    Serialize seek actions and fix state change action serialization
    
    https://bugzilla.gnome.org/show_bug.cgi?id=739251

 pitivi/utils/pipeline.py |   20 +++++++++++++++++---
 pitivi/viewer.py         |   15 ++++++++-------
 2 files changed, 25 insertions(+), 10 deletions(-)
---
diff --git a/pitivi/utils/pipeline.py b/pitivi/utils/pipeline.py
index 9b57bfa..7592fe1 100644
--- a/pitivi/utils/pipeline.py
+++ b/pitivi/utils/pipeline.py
@@ -39,7 +39,7 @@ from pitivi.utils.misc import format_ns
 MAX_RECOVERIES = 5
 
 PIPELINE_SIGNALS = {
-    "state-change": (GObject.SignalFlags.RUN_LAST, None, (GObject.TYPE_INT,)),
+    "state-change": (GObject.SignalFlags.RUN_LAST, None, (GObject.TYPE_INT, GObject.TYPE_INT)),
     "position": (GObject.SignalFlags.RUN_LAST, None, (GObject.TYPE_UINT64,)),
     "duration-changed": (GObject.SignalFlags.RUN_LAST, None, (GObject.TYPE_UINT64,)),
     "eos": (GObject.SignalFlags.RUN_LAST, None, ()),
@@ -437,7 +437,7 @@ class SimplePipeline(GObject.Object, Loggable):
                     self._listenToPosition(False)
 
                 if emit_state_change:
-                    self.emit('state-change', new)
+                    self.emit('state-change', new, prev)
 
         elif message.type == Gst.MessageType.ERROR:
             error, detail = message.parse_error()
@@ -526,10 +526,12 @@ class Pipeline(GES.Pipeline, SimplePipeline):
 
     __gsignals__ = PIPELINE_SIGNALS
 
-    def __init__(self, pipeline=None):
+    def __init__(self, app, pipeline=None):
         GES.Pipeline.__init__(self)
         SimplePipeline.__init__(self, self)
 
+        self.app = app
+
         self._timeline = None
         self._seeker = Seeker()
         self._seeker.connect("seek", self._seekCb)
@@ -589,3 +591,15 @@ class Pipeline(GES.Pipeline, SimplePipeline):
         end of the timeline.
         """
         self.simple_seek(position)
+
+    def simple_seek(self, position):
+        st = Gst.Structure.new_empty("seek")
+
+        if self.getState() == Gst.State.PLAYING:
+            st.set_value("playback_time", float(self.getPosition()) / Gst.SECOND)
+
+        st.set_value("start", float(position / Gst.SECOND))
+        st.set_value("flags", "accurate+flush")
+        self.app.write_action(st)
+
+        SimplePipeline.simple_seek(self, position)
diff --git a/pitivi/viewer.py b/pitivi/viewer.py
index 250a68c..fdcbf1a 100644
--- a/pitivi/viewer.py
+++ b/pitivi/viewer.py
@@ -444,7 +444,7 @@ class ViewerContainer(Gtk.VBox, Loggable):
             self.setPipeline(self.app.project_manager.current_project.pipeline, self._oldTimelinePos)
             self.debug("Back to the project's pipeline")
 
-    def _pipelineStateChangedCb(self, unused_pipeline, state):
+    def _pipelineStateChangedCb(self, unused_pipeline, state, old_state):
         """
         When playback starts/stops, update the viewer widget,
         play/pause button and (un)inhibit the screensaver.
@@ -453,16 +453,17 @@ class ViewerContainer(Gtk.VBox, Loggable):
         """
         if int(state) == int(Gst.State.PLAYING):
             st = Gst.Structure.new_empty("play")
-            st.set_value("playback_time", float(self.pipeline.getPosition())
-                / Gst.SECOND)
             self.app.write_action(st)
             self.playpause_button.setPause()
             self.system.inhibitScreensaver(self.INHIBIT_REASON)
         elif int(state) == int(Gst.State.PAUSED):
-            st = Gst.Structure.new_empty("pause")
-            st.set_value("playback_time", float(self.pipeline.getPosition()) /
-                Gst.SECOND)
-            self.app.write_action(st)
+            if old_state != int(Gst.State.PAUSED):
+                st = Gst.Structure.new_empty("pause")
+                if old_state == int(Gst.State.PLAYING):
+                    st.set_value("playback_time", float(self.pipeline.getPosition()) /
+                        Gst.SECOND)
+                self.app.write_action(st)
+
             self.playpause_button.setPlay()
             self.system.uninhibitScreensaver(self.INHIBIT_REASON)
         else: