Fri, 13 Jun 2008 14:27:30 +0200 <thp@perli.net>

Merge patch from Justin Forest to speed up pubDate detection

	* src/gpodder/gui.py: Add Justin Forest to the list of contributors
	and make sure we clear the pubDate cache in the channel when changing
	episode downloaded status manually
	* src/gpodder/libpodcasts.py: Merge patch from Justin Forest to speed
	up the newest_pubdate_downloaded() function by caching its value
	instead of re-calculating it on every call



git-svn-id: svn://svn.berlios.de/gpodder/trunk@735 b0d088ad-0a06-0410-aad2-9ed5178a7e87

ChangeLog

@@ -1,3 +1,13 @@
+Fri, 13 Jun 2008 14:27:30 +0200 <thp@perli.net>
+Merge patch from Justin Forest to speed up pubDate detection
+
+	* src/gpodder/gui.py: Add Justin Forest to the list of contributors
+	and make sure we clear the pubDate cache in the channel when changing
+	episode downloaded status manually
+	* src/gpodder/libpodcasts.py: Merge patch from Justin Forest to speed
+	up the newest_pubdate_downloaded() function by caching its value
+	instead of re-calculating it on every call
+
 Fri, 13 Jun 2008 09:37:45 +0200 <thp@perli.net>
 Merge patch from Nick to add support for deleting played files on sync
 

src/gpodder/gui.py

@@ -84,7 +84,7 @@ app_authors = [
     'Jérôme Chabod', 'Jerry Moss',
     'Jessica Henline', 'João Trindade', 'Joel Calado', 'John Ferguson', 
     'José Luis Fustel', 'Joseph Bleau', 'Julio Acuña', 'Junio C Hamano',
-    'Jürgen Schinker',
+    'Jürgen Schinker', 'Justin Forest',
     'Konstantin Ryabitsev', 'Leonid Ponomarev', 'Marcos Hernández', 'Mark Alford', 'Michael Salim', 
     'Mika Leppinen', 'Mike Coulson', 'Mykola Nikishov', 'narf at inode.at',
     'Nick L.', 'Nicolas Quienot', 'Ondrej Vesely', 
@@ -1371,6 +1371,10 @@ class gPodder(GladeWidget):
 
         self.for_each_selected_episode_url( callback)
 
+        if self.active_channel:
+            # Reset the cache for newest_pubdate_downloaded
+            self.active_channel.reset_pubdate_cache()
+
     def on_item_toggle_played_activate( self, widget, toggle = True, new_value = False):
         if toggle:
             callback = lambda url: gl.history_mark_played(url, not gl.history_is_played(url))

src/gpodder/libpodcasts.py

@@ -216,6 +216,7 @@ class podcastChannel(list):
         self.image = None
         self.pubDate = ''
         self.parse_error = None
+        self.newest_pubdate_cached = None
 
         # should this channel be synced to devices? (ex: iPod)
         self.sync_to_devices = True
@@ -294,17 +295,43 @@ class podcastChannel(list):
 
         ChannelSettings.set_settings_by_url( self.url, settings)
 
-    def newest_pubdate_downloaded( self):
-        # Try DownloadHistory's entries first
-        for episode in self:
-            if gl.history_is_downloaded( episode.url):
-                return episode.pubDate
+    def reset_pubdate_cache(self):
+        self.newest_pubdate_cached = None
 
-        # If nothing found, do pubDate comparison
-        pubdate = None
-        for episode in self.load_downloaded_episodes():
-            pubdate = episode.newer_pubdate( pubdate)
-        return pubdate
+    def newest_pubdate_downloaded(self):
+        """
+        Returns the most recent pubDate value of all downloaded episodes, or 
+        None if the pubDate cannot be determined.
+
+        This value is cached for speedup. You can call reset_pubdate_cache()
+        to clear the cached value and re-calculate the newest pubDate.
+        """
+
+        if self.newest_pubdate_cached == 0:
+            return None
+
+        elif self.newest_pubdate_cached is None:
+            # Try DownloadHistory's entries first
+            for episode in self:
+                if gl.history_is_downloaded( episode.url):
+                    self.newest_pubdate_cached = episode.pubDate
+                    return episode.pubDate
+
+            # If nothing found, do pubDate comparison
+            pubdate = None
+            for episode in self.load_downloaded_episodes():
+                pubdate = episode.newer_pubdate( pubdate)
+
+            if pubdate is None:
+                # Zero value is used when there are episodes in the channel,
+                # but none of them are downloaded.
+                self.newest_pubdate_cached = 0
+            else:
+                self.newest_pubdate_cached = pubdate
+
+            return pubdate
+
+        return self.newest_pubdate_cached
     
     def episode_is_new(self, episode, last_pubdate = None):
         if last_pubdate is None:
@@ -386,6 +413,13 @@ class podcastChannel(list):
                 except:
                     log('Error while calling update_metadata_on_file() :(')
 
+        # Update the cached newest_pubdate_downloaded() result.
+        newest = self.newest_pubdate_downloaded()
+        if newest is None:
+            self.newest_pubdate_cached = item.pubDate
+        else:
+            self.newest_pubdate_cached = item.newer_pubdate(newest)
+
         gl.history_mark_downloaded(item.url)
         self.update_m3u_playlist(downloaded_episodes)