[gnome-music/wip/smart_playlists: 1/5] Add 'Recently Added' playlist - last 50 added songs

[Vadim Rutkovsky <vrutkovsky src gnome org>]

commit 06f06aa675883aca8dc727f349c28588862b4022
Author: Vadim Rutkovsky <vrutkovs redhat com>
Date:   Tue Apr 22 14:30:56 2014 +0200

    Add 'Recently Added' playlist - last 50 added songs

 gnomemusic/query.py |   17 +++++++++++++++++
 gnomemusic/view.py  |   16 ++++++++++++++++
 2 files changed, 33 insertions(+), 0 deletions(-)
---
diff --git a/gnomemusic/query.py b/gnomemusic/query.py
index fc8b8f3..06b7bd6 100644
--- a/gnomemusic/query.py
+++ b/gnomemusic/query.py
@@ -224,6 +224,23 @@ class Query():
     }
     '''.replace('\n', ' ').strip()
 
+    RECENTLY_ADDED = '''
+        SELECT DISTINCT
+            rdf:type(?song)
+            tracker:id(?song) AS id
+            nie:url(?song) AS url
+            nie:title(?song) AS title
+            nmm:artistName(nmm:performer(?song)) AS artist
+            nie:title(nmm:musicAlbum(?song)) AS album
+            nfo:duration(?song) AS duration
+            nie:contentCreated(?song) AS time
+        WHERE {
+          ?song a nmm:MusicPiece ;
+                a nfo:FileDataObject
+        }
+        ORDER BY DESC(?time)
+    '''.replace('\n', ' ').strip()
+
     @staticmethod
     def album_songs(album_id):
         query = '''
diff --git a/gnomemusic/view.py b/gnomemusic/view.py
index c1b3112..ef76409 100644
--- a/gnomemusic/view.py
+++ b/gnomemusic/view.py
@@ -1148,6 +1148,7 @@ class Playlist(ViewContainer):
 
     @log
     def populate(self):
+        self.add_predefined_playlists()
         for item in sorted(self.playlists_list):
             self._add_playlist_item(item)
         if len(self.playlists_list):
@@ -1161,3 +1162,18 @@ class Playlist(ViewContainer):
     def get_selected_track_uris(self, callback):
         callback([self.filter.get_value(self.filter.get_iter(path), 5).get_url()
                   for path in self.view.get_selection()])
+
+    @log
+    def add_predefined_playlists(self):
+        self.add_predefined_playlist(_("Recently Added"), Query.RECENTLY_ADDED)
+
+    @log
+    def add_predefined_playlist(self, name, query):
+        self._on_playlist_created(None, name)
+
+        def _add_predefined_playlist_cb(source, param, item, remaining):
+            if item and item.get_url():
+                self._on_song_added_to_playlist(None, name, item)
+
+        grilo.populate_items(query, 0, _add_predefined_playlist_cb)
+