scoffey · November 25, 2010 04:49 · Nov 25, 2010
diff --git a/pytunes.py b/pytunes.py
@@ -0,0 +1,89 @@
+#!/usr/bin/env python
+# -*- coding: utf-8 -*-
+
+"""
+This script implements an algorithm for sorting a given iTunes playlist
+according to the least played tracks in each album.
+
+It aims to identify the tracks that were played the least and to show
+how many times they should be played in order to reach the same playcount
+as the most played track in the album they belong to.
+
+The program input is the name of the playlist where tracks should be
+taken from and the name of the new playlist to create or replace. The
+output, apart from the new iTunes playlist, is a table showing the
+candidate tracks and the playcount difference used for sorting them.
+"""
+
+__author__ = 'Santiago Coffey'
+__email__ = '[email protected]'
+__version__ = '0.1'
+__license__ = 'GNU General Public License 3'
+__docformat__ = 'restructuredtext en'
+
+import sys
+
+import appscript
+
+iTunes = appscript.app('itunes')
+
+def make_catalog(tracks):
+    """ Makes a music catalog dict by artist+album with track playcounts """
+    catalog = dict()
+    for track in tracks:
+        artist = track.album_artist() or track.artist()
+        album = track.album()
+        album_list = catalog.get((artist, album), {})
+        album_list[track] = track.played_count()
+        catalog[(artist, album)] = album_list
+    return catalog
+
+def make_tracks_tuples(album_list, artist, album):
+    """ Returns tuples with artist name, album name, track object and
+        playcount difference """
+    max_playcount = max(album_list.values())
+    return [(artist, album, track, max_playcount - n) for track, n \
+            in album_list.iteritems() if n < max_playcount]
+
+def get_candidates(playlist):
+    """ Returns candidate tracks data sorted by playcount difference """
+    candidates = []
+    catalog = make_catalog(playlist.file_tracks())
+    for artist_album, album_list in catalog.iteritems():
+        tuples = make_tracks_tuples(album_list, *artist_album)
+        candidates.extend(tuples)
+    candidates.sort(key=lambda x: x[3], reverse=True)
+    return candidates
+
+def show_candidates(candidates):
+    """ Prints candidate tracks data as a table """
+    template = '\t | '.join(['%s'] * 4)
+    for artist, album, track, count in candidates:
+        print template % (count, artist, album, track.name())
+
+def replace_playlist(name, tracks):
+    """ Creates or replaces an iTunes playlist with given tracks """
+    playlist = iTunes.user_playlists[name]
+    if iTunes.exists(playlist): # empty existing playlist
+        if len(playlist.tracks()):
+            iTunes.delete(playlist.tracks)
+    else: # create playlist
+        iTunes.make(new=appscript.k.playlist, \
+                with_properties={appscript.k.name: name})
+    for track in tracks:
+        iTunes.duplicate(track, to=playlist)
+
+def main(program, *args):
+    """ Main program: Computes and creates new playlist according to input """
+    source = raw_input('Enter your source playlist name: ')
+    playlist = iTunes.user_playlists[source]
+    if iTunes.exists(playlist):
+        destination = raw_input('Enter your destination playlist name: ')
+        candidates = get_candidates(playlist)
+        show_candidates(candidates)
+        replace_playlist(destination, [i[2] for i in candidates])
+    else:
+        print 'Error: No such iTunes playlist: %s' % source
+
+if __name__ == '__main__':
+    main(*sys.argv)