[pitivi] previewers: Do not fail if thumbnail timestamp is not the requested one

[Mathieu Duponchelle <mathieudu src gnome org>]

commit c296ebf740fbb51e5afdd58d7bb1b482a5f3800e
Author: Thibault Saunier <thibault saunier collabora com>
Date:   Fri Dec 6 18:14:35 2013 -0300

    previewers: Do not fail if thumbnail timestamp is not the requested one
    
    We should not miserably fail if the video thumbnail's timestamp is
    not the exact requested one. Instead we try to figure out what the
    timestamp means.

 pitivi/timeline/previewers.py |   26 ++++++++++++++++++++++----
 1 files changed, 22 insertions(+), 4 deletions(-)
---
diff --git a/pitivi/timeline/previewers.py b/pitivi/timeline/previewers.py
index 09724f1..f2f0799 100644
--- a/pitivi/timeline/previewers.py
+++ b/pitivi/timeline/previewers.py
@@ -31,6 +31,7 @@ import os
 import pickle
 import resource
 import sqlite3
+import bisect
 
 # Our C module optimizing waveforms rendering
 import renderer
@@ -40,7 +41,7 @@ from pitivi.utils.signal import Signallable
 from pitivi.utils.loggable import Loggable
 from pitivi.utils.timeline import Zoomable
 from pitivi.utils.ui import EXPANDED_SIZE
-from pitivi.utils.misc import filename_from_uri, quote_uri, hash_file
+from pitivi.utils.misc import filename_from_uri, quote_uri, hash_file, print_ns
 from pitivi.utils.ui import CONTROL_WIDTH
 
 
@@ -384,7 +385,7 @@ class VideoPreviewer(Clutter.ScrollActor, PreviewGenerator, Zoomable, Loggable):
             if wish in self.queue:
                 return wish
 
-    def _setThumbnail(self, time, thumbnail):
+    def _setThumbnail(self, time, pixbuf):
         # TODO: is "time" guaranteed to be nanosecond precise?
         # => __tim says: "that's how it should be"
         # => also see gst-plugins-good/tests/icles/gdkpixbufsink-test
@@ -393,10 +394,25 @@ class VideoPreviewer(Clutter.ScrollActor, PreviewGenerator, Zoomable, Loggable):
         if time in self.queue:
             self.queue.remove(time)
 
-        self.thumb_cache[time] = thumbnail
+        self.thumb_cache[time] = pixbuf
 
         if time in self.thumbs:
-            self.thumbs[time].set_from_gdkpixbuf_animated(thumbnail)
+            self.thumbs[time].set_from_gdkpixbuf_animated(pixbuf)
+        else:
+            sorted_times = self.thumbs.keys()
+            sorted_times.sort()
+            index = bisect.bisect(sorted_times, time)
+            time = sorted_times[index]
+            thumb = self.thumbs[sorted_times[index]]
+            if thumb.has_pixel_data and len(sorted_times) > index + 1:
+                # It might actually be the follwoing thumbnail we were
+                time = sorted_times[index + 1]
+                thumb = self.thumbs[time]
+                if thumb.has_pixel_data:
+                    self.error("Surrounding thumbnails are already set "
+                               "for timestamp %s" % print_ns(time))
+                    return
+            self.thumbs[time].set_from_gdkpixbuf_animated(pixbuf)
 
     # Interface (Zoomable)
 
@@ -527,11 +543,13 @@ class Thumbnail(Clutter.Actor):
         #self.set_background_color(Clutter.Color.new(0, 100, 150, 100))
         self.set_opacity(0)
         self.set_size(self.width, self.height)
+        self.has_pixel_data = False
 
     def set_from_gdkpixbuf(self, gdkpixbuf):
         row_stride = gdkpixbuf.get_rowstride()
         pixel_data = gdkpixbuf.get_pixels()
         alpha = gdkpixbuf.get_has_alpha()
+        self.has_pixel_data = True
         if alpha:
             self.props.content.set_data(pixel_data, Cogl.PixelFormat.RGBA_8888,
                                         self.width, self.height, row_stride)