[pitivi] previewers: Link created preview caches files to proxy targets

[Thibault Saunier <tsaunier src gnome org>]

commit 8224b87105b2b13b9b0c6cee5dca9b9fd9e00563
Author: Thibault Saunier <thibault saunier osg samsung com>
Date:   Fri Feb 3 18:05:27 2017 -0300

    previewers: Link created preview caches files to proxy targets
    
    In the case the proxy already exists on the filesystem and thus is used
    but the previewer cache files do not exist.

 pitivi/timeline/previewers.py |   19 ++++++++++++++++++-
 1 files changed, 18 insertions(+), 1 deletions(-)
---
diff --git a/pitivi/timeline/previewers.py b/pitivi/timeline/previewers.py
index 34f99d3..946f802 100644
--- a/pitivi/timeline/previewers.py
+++ b/pitivi/timeline/previewers.py
@@ -274,6 +274,10 @@ class WaveformPreviewer(PreviewerBin):
         if proxy:
             proxy_wavefile = get_wavefile_location_for_uri(proxy.get_id())
             self.debug("symlinking %s and %s", self.wavefile, proxy_wavefile)
+            try:
+                os.remove(proxy_wavefile)
+            except FileNotFoundError:
+                pass
             os.symlink(self.wavefile, proxy_wavefile)
 
 
@@ -405,6 +409,7 @@ class VideoPreviewer(Previewer, Zoomable, Loggable):
 
         self.thumbs = {}
         self.thumb_cache = ThumbnailCache.get(self.uri)
+        self._ensure_proxy_thumbnails_cache()
         self.thumb_width, unused_height = self.thumb_cache.getImagesSize()
 
         self.cpu_usage_tracker = CPUUsageTracker()
@@ -681,6 +686,12 @@ class VideoPreviewer(Previewer, Zoomable, Loggable):
         self._setupPipeline()
         self._startThumbnailingWhenIdle()
 
+    def _ensure_proxy_thumbnails_cache(self):
+        """Ensures that both the target asset and the proxy assets have caches"""
+        asset_uri = quote_uri(self.ges_elem.get_parent().get_asset().props.id)
+        if self.uri != asset_uri:
+            self.thumb_cache.copy(asset_uri)
+
     def stopGeneration(self):
         if self._thumb_cb_id:
             GLib.source_remove(self._thumb_cb_id)
@@ -690,6 +701,8 @@ class VideoPreviewer(Previewer, Zoomable, Loggable):
             self.pipeline.set_state(Gst.State.NULL)
             self.pipeline.get_state(Gst.CLOCK_TIME_NONE)
             self.pipeline = None
+
+        self._ensure_proxy_thumbnails_cache()
         self.emit("done")
 
     def release(self):
@@ -759,6 +772,10 @@ class ThumbnailCache(Loggable):
         thumbs_cache_dir = get_dir(os.path.join(xdg_cache_home(), "thumbs"))
         dbfile = os.path.join(thumbs_cache_dir, filehash)
 
+        try:
+            os.remove(dbfile)
+        except FileNotFoundError:
+            pass
         os.symlink(self._dbfile, dbfile)
 
     def getImagesSize(self):
@@ -1025,7 +1042,7 @@ class AudioPreviewer(Previewer, Zoomable, Loggable):
         self._force_redraw = True
 
     def _prepareSamples(self):
-        self._wavebin.finalize()
+        self._wavebin.finalize(proxy=get_proxy_target(self.ges_elem))
         self.samples = self._wavebin.samples
 
     def _startRendering(self):