song: convert to a subclass of dict.

also don't store whole song in Library and Playlist,
this saves a significant amount of memory.

9 files changed, 125 insertions, 93 deletions

diff --git a/nephilim/common.py b/nephilim/common.py
index 5c12225..1249ec7 100644
--- a/nephilim/common.py
+++ b/nephilim/common.py
@@ -72,10 +72,10 @@ def expand_tags(str, expanders):
 def generate_metadata_path(song, dir_tag, file_tag):
     """Generate dirname and (db files only) full file path for reading/writing metadata files
        (cover, lyrics) from $tags in dir/filename."""
-    if QtCore.QDir.isAbsolutePath(song.filepath()):
-        dirname  = os.path.dirname(song.filepath())
+    if QtCore.QDir.isAbsolutePath(song['file']):
+        dirname  = os.path.dirname(song['file'])
         filepath = ''
-    elif '://' in song.filepath():   # we are streaming
+    elif '://' in song['file']:   # we are streaming
         dirname  = ''
         filepath = ''
     else:
diff --git a/nephilim/mpclient.py b/nephilim/mpclient.py
index 35be3f5..bd137ea 100644
--- a/nephilim/mpclient.py
+++ b/nephilim/mpclient.py
@@ -21,7 +21,7 @@ import mpd
 import socket
 import logging
 
-from song import Song
+from song import Song, SongRef, PlaylistEntryRef
 
 class MPClient(QtCore.QObject):
     """This class offers another layer above pympd, with usefull events."""
@@ -45,7 +45,7 @@ class MPClient(QtCore.QObject):
     # SIGNALS
     connect_changed  = QtCore.pyqtSignal(bool)
     db_updated       = QtCore.pyqtSignal()
-    song_changed     = QtCore.pyqtSignal(str)
+    song_changed     = QtCore.pyqtSignal(object)
     time_changed     = QtCore.pyqtSignal(int)
     state_changed    = QtCore.pyqtSignal(str)
     volume_changed   = QtCore.pyqtSignal(int)
@@ -87,7 +87,7 @@ class MPClient(QtCore.QObject):
             self.logger.error('Don\'t have MPD read permission, diconnecting.')
             return self.disconnect_mpd()
 
-        self._update_current_song()
+        self.__update_current_song()
         self._db_update = self.stats()['db_update']
 
         self.emit(QtCore.SIGNAL('connected')) #should be removed
@@ -139,7 +139,7 @@ class MPClient(QtCore.QObject):
     def status(self):
         """Get current MPD status."""
         return self._status
-    def playlist(self):
+    def playlistinfo(self):
         """Returns a list of songs in current playlist."""
         self.logger.info('Listing current playlist.')
         if not self.__check_command_ok('playlistinfo'):
@@ -368,7 +368,7 @@ class MPClient(QtCore.QObject):
         return map(lambda entry: Song(entry)
             , filter(lambda entry: not('directory' in entry), array)
             )
-    def _update_current_song(self):
+    def __update_current_song(self):
         """Update the current song."""
         song = self._retrieve(self._client.currentsong)
         if not song:
@@ -424,10 +424,10 @@ class MPClient(QtCore.QObject):
         if not self._status:
             return self.disconnect_mpd()
 
-        self._update_current_song()
+        self.__update_current_song()
 
         if self._status['songid'] != old_status['songid']:
-            self.song_changed.emit(self._status['songid'])
+            self.song_changed.emit(PlaylistEntryRef(self, self._status['songid']))
 
         if self._status['time'] != old_status['time']:
             self.time_changed.emit(self._status['time'])
diff --git a/nephilim/plugins/AlbumCover.py b/nephilim/plugins/AlbumCover.py
index db4d6f8..01aa333 100644
--- a/nephilim/plugins/AlbumCover.py
+++ b/nephilim/plugins/AlbumCover.py
@@ -221,9 +221,9 @@ class AlbumCover(Plugin):
             url = QtCore.QUrl('http://ws.audioscrobbler.com/2.0/')
             url.setQueryItems([('api_key', 'c325945c67b3e8327e01e3afb7cdcf35'),
                                ('method',  'album.getInfo'),
-                               ('artist',  song.artist()),
-                               ('album',   song.album()),
-                               ('mbid',    song.tag('MUSICBRAINZ_ALBUMID'))])
+                               ('artist',  song['artist']),
+                               ('album',   song['album']),
+                               ('mbid',    song['MUSICBRAINZ_ALBUMID'])])
             self.fetch2(song, url)
             self.rep.finished.connect(self.__handle_search_res)
 
@@ -390,7 +390,7 @@ class AlbumCover(Plugin):
         self.__abort_fetch()
 
         file = QtGui.QFileDialog.getOpenFileName(None,
-                'Select album cover for %s - %s'%(song.artist(), song.album()),
+                'Select album cover for %s - %s'%(song['artist'], song['album']),
                 self.__cover_dir, '')
         if not file:
             return
diff --git a/nephilim/plugins/Library.py b/nephilim/plugins/Library.py
index 74c5464..50f85a3 100644
--- a/nephilim/plugins/Library.py
+++ b/nephilim/plugins/Library.py
@@ -83,6 +83,11 @@ class LibraryWidget(QtGui.QWidget):
     plugin        = None
     logger        = None
 
+    class LibrarySongItem(QtGui.QStandardItem):
+        # public
+        "Song path"
+        path    = None
+
     class LibraryModel(QtGui.QStandardItemModel):
         def fill(self, songs, mode):
             self.clear()
@@ -91,7 +96,7 @@ class LibraryWidget(QtGui.QWidget):
             for song in songs:
                 cur_item = tree
                 for part in mode.split('/'):
-                    tag = song.tag(part)
+                    tag = song[part]
                     if isinstance(tag, list):
                         tag = tag[0]            #FIXME hack to make songs with multiple genres work.
                     if not tag:
@@ -104,11 +109,10 @@ class LibraryWidget(QtGui.QWidget):
                         cur_item[1].appendRow(it)
                         cur_item[0][tag] = [{}, it]
                         cur_item = cur_item[0][tag]
-                it = QtGui.QStandardItem('%s%02d %s'%(song.tag('disc') + '/' if song.tag('disc') else '',
-                    song.track() if song.track() else 0,
-                    song.title() if song.title() else song.filepath()))
+                it = LibraryWidget.LibrarySongItem('%s%02d %s'%(song['disc'] + '/' if 'disc' in song else '',
+                                         song['tracknum'], song['title']))
+                it.path = song['file']
                 it.setFlags(QtCore.Qt.ItemIsSelectable|QtCore.Qt.ItemIsEnabled)
-                it.setData(QVariant(song), QtCore.Qt.UserRole)
                 cur_item[1].appendRow(it)
 
             self.sort(0, QtCore.Qt.AscendingOrder)
@@ -196,8 +200,8 @@ class LibraryWidget(QtGui.QWidget):
         self.plugin.mpclient.add(paths)
 
     def item_to_playlist(self, item, add_queue):
-        if not item.hasChildren():
-            add_queue.append(item.data(QtCore.Qt.UserRole).toPyObject().filepath())
+        if isinstance(item, self.LibrarySongItem):
+            add_queue.append(item.path)
         else:
             for i in range(item.rowCount()):
                 self.item_to_playlist(item.child(i), add_queue)
diff --git a/nephilim/plugins/Lyrics.py b/nephilim/plugins/Lyrics.py
index 9217df8..3b6224f 100644
--- a/nephilim/plugins/Lyrics.py
+++ b/nephilim/plugins/Lyrics.py
@@ -91,7 +91,7 @@ class LyricsWidget(QtGui.QWidget):
 
         self.__text_view.clear()
         self.__label.setText('<b>%s</b> by <u>%s</u> on <u>%s</u>'\
-                             %(song.title(), song.artist(), song.album()))
+                             %(song['title'], song['artist'], song['album']))
         if lyrics:
             self.logger.info('Setting new lyrics.')
             self.__text_view.insertPlainText(lyrics.decode('utf-8'))
@@ -147,7 +147,7 @@ class Lyrics(Plugin):
 
         def fetch(self, song):
             url = QtCore.QUrl('http://lyricwiki.org/api.php')
-            url.setQueryItems([('func', 'getArtist'), ('artist', song.artist()),
+            url.setQueryItems([('func', 'getArtist'), ('artist', song['artist']),
                                     ('fmt', 'xml')])
             self.fetch2(song, url)
             self.rep.finished.connect(self.__handle_artist_res)
@@ -167,7 +167,7 @@ class Lyrics(Plugin):
 
             url = QtCore.QUrl('http://lyricwiki.org/api.php')
             url.setQueryItems([('func', 'getSong'), ('artist', artist),
-                               ('song', self.song.title()), ('fmt', 'xml')])
+                               ('song', self.song['title']), ('fmt', 'xml')])
             self.rep = self.nam.get(QtNetwork.QNetworkRequest(url))
             self.rep.finished.connect(self.__handle_search_res)
 
@@ -215,7 +215,7 @@ class Lyrics(Plugin):
 
         def fetch(self, song):
             url = QtCore.QUrl('http://www.animelyrics.com/search.php')
-            url.setQueryItems([('t', 'performer'), ('q', song.artist())])
+            url.setQueryItems([('t', 'performer'), ('q', song['artist'])])
             self.fetch2(song, url)
             self.rep.finished.connect(self.__handle_search_res)
 
@@ -229,7 +229,7 @@ class Lyrics(Plugin):
 
             url = None
             for elem in tree.iterfind('.//a'):
-                if ('href' in elem.attrib) and elem.text and (self.song.title() in elem.text):
+                if ('href' in elem.attrib) and elem.text and (self.song['title'] in elem.text):
                     url = QtCore.QUrl('http://www.animelyrics.com/%s'%elem.get('href'))
 
             if not url:
diff --git a/nephilim/plugins/Playlist.py b/nephilim/plugins/Playlist.py
index 44d7a40..d8147bc 100644
--- a/nephilim/plugins/Playlist.py
+++ b/nephilim/plugins/Playlist.py
@@ -44,6 +44,14 @@ class PlaylistWidget(QtGui.QWidget):
     plugin   = None
     playlist = None
 
+    class PlaylistSongItem(QtGui.QTreeWidgetItem):
+        # public
+        id = -1
+
+        def __init__(self, id):
+            QtGui.QTreeWidgetItem.__init__(self)
+            self.id = id
+
     def __init__(self, plugin):
         QtGui.QWidget.__init__(self)
         self.plugin = plugin
@@ -55,7 +63,6 @@ class PlaylistWidget(QtGui.QWidget):
         self.layout().setMargin(0)
         self.layout().addWidget(self.playlist)
 
-
     class Playlist(QtGui.QTreeWidget):
         song   = None
         plugin = None
@@ -80,23 +87,22 @@ class PlaylistWidget(QtGui.QWidget):
             self.plugin.settings.setValue(self.plugin.name + '/header_state', QVariant(self.header().saveState()))
 
         def _song_activated(self, item):
-            self.plugin.mpclient.play(item.data(0, QtCore.Qt.UserRole).toPyObject().id())
+            self.plugin.mpclient.play(item.id)
 
         def fill(self):
             columns = self.plugin.settings.value(self.plugin.name + '/columns').toStringList()
             self.clear()
-            for song in self.plugin.mpclient.playlist():
-                item = QtGui.QTreeWidgetItem()
+            for song in self.plugin.mpclient.playlistinfo():
+                item = PlaylistWidget.PlaylistSongItem(song['id'])
                 for i in range(len(columns)):
-                    item.setText(i, unicode(song.tag(str(columns[i]))))
-                item.setData(0, QtCore.Qt.UserRole, QVariant(song))
+                    item.setText(i, unicode(song[str(columns[i])]))
                 self.addTopLevelItem(item)
 
         def keyPressEvent(self, event):
             if event.matches(QtGui.QKeySequence.Delete):
                 ids = []
                 for item in self.selectedItems():
-                    ids.append(item.data(0, QtCore.Qt.UserRole).toPyObject().id())
+                    ids.append(item.id)
 
                 self.plugin.mpclient.delete(ids)
             else:
diff --git a/nephilim/plugins/Songinfo.py b/nephilim/plugins/Songinfo.py
index cad5dd0..144033b 100644
--- a/nephilim/plugins/Songinfo.py
+++ b/nephilim/plugins/Songinfo.py
@@ -105,7 +105,7 @@ class Songinfo(Plugin):
         song = self.mpclient.current_song()
 
         for tag in self.__tags:
-            metadata[tag] = song.tag(str(tag), '') if song else ''  #XXX i don't like the explicit conversion to python string
+            metadata[tag] = song[str(tag)] if song else ''  #XXX i don't like the explicit conversion to python string
         self.o.set_metadata(metadata)
 
 class SonginfoWidget(QtGui.QWidget):
diff --git a/nephilim/song.py b/nephilim/song.py
index 0f1a627..c9c1145 100644
--- a/nephilim/song.py
+++ b/nephilim/song.py
@@ -1,5 +1,4 @@
 #
-#    Copyright (C) 2008 jerous <jerous@gmail.com>
 #    Copyright (C) 2009 Anton Khirnov <wyskas@gmail.com>
 #
 #    Nephilim is free software: you can redistribute it and/or modify
@@ -21,80 +20,103 @@ import os
 
 from common import sec2min
 
-class Song:
-    """The Song class offers an abstraction of a song."""
-    _data = None
+class Song(dict):
+    """Song provides a dictionary-like wrapper around song metadata.
+       Its instances _shouldn't_ be stored, use SongRef or PlaylistEntryRef for that."""
 
     def __init__(self, data):
-        self._data = data
-        if 'track' in self._data:
-            try:
-                self._data['track'] = int(self._data['track'])
-            except ValueError:
-                # OGG tracks come in #track/#total format
-                try:
-                    self._data['track'] = int(self._data['track'].split('/')[0])
-                except ValueError:
-                    self._data['track'] = 0
+        # decode all strings to unicode
+        for tag in data:
+            if isinstance(data[tag], str):
+                data[tag] = data[tag].decode('utf-8')
 
-        # ensure all string-values are utf-8 encoded
-        for tag in self._data.keys():
-            if isinstance(self._data[tag], str):
-                self._data[tag] = self._data[tag].decode('utf-8')
-        if 'time' in self._data:
-            self._data['time']   = int(self._data['time'])
-            self._data['timems'] = '%i:%i'%(self._data['time'] / 60, self._data['time'] % 60)
-            self._data['length'] = sec2min(self._data['time'])
+        dict.__init__(self, data)
 
     def __eq__(self, other):
         if not isinstance(other, Song):
             return NotImplemented
-        return self._data['file'] == other._data['file']
+        return self['file'] == other['file']
 
     def __ne__(self, other):
         if not isinstance(other, Song):
             return NotImplemented
-        return self._data['file'] != other._data['file']
+        return self['file'] != other['file']
 
-    def id(self):
-        """Get the song's playlist ID. (-1 if not in playlist)."""
-        return self.tag('id', '-1')
+    def __getitem__(self, key):
+        try:
+            return dict.__getitem__(self, key)
+        except KeyError:
+            if key == 'tracknum':
+                try:
+                    return int(self['track'])
+                except ValueError:
+                    try:
+                        return int(self['track'].split('/')[0])
+                    except ValueError:
+                        return 0
+            elif key == 'length':
+                return sec2min(int(self['time']))
+            elif key == 'id':
+                return '-1'
+            elif key == 'title':
+                return self['file']
+            return ''
+
+    def __nonzero__(self):
+        return bool(self['file'])
 
-    def title(self):
-        """Get the song's title (or filename if it has no title)."""
-        return self.tag('title', self._data['file'])
+    def expand_tags(self, str):
+        """Expands tags in form $tag in str."""
+        ret = str
+        ret = ret.replace('$title', self['title'])    #to ensure that it is set to at least filename
+        for tag in self.keys() + ['tracknum', 'length', 'id']:
+            ret = ret.replace('$' + tag, unicode(self[tag]))
+        ret = ret.replace('$songdir', os.path.dirname(self['file']))
+        return ret
 
-    def artist(self):
-        """Get the song's artist."""
-        return self.tag('artist')
 
-    def track(self):
-        """Get the song's track number."""
-        return self.tag('track')
+class SongRef:
+    """SongRef stores only a reference to the song (uri) instead
+       of full metadata to conserve memory. Song's tags can be accessed
+       as in Song, but it requires a call to MPD for each tag. """
+    path     = None
+    mpclient = None
 
-    def album(self):
-        """Get the album."""
-        return self.tag('album')
+    def __init__(self, mpclient, path):
+        self.mpclient = mpclient
+        self.path     = path
 
-    def filepath(self):
-        """Get the filepath."""
-        return self._data['file']
+    def __getitem__(self, key):
+        return self.song()[key]
 
-    def tag(self, tag, default=''):
-        """Get a tag. If it doesn't exist, return default."""
-        if tag in self._data:
-            return self._data[tag]
-        if tag=='song':
-            return self.__str__()
+    def __nonzero__(self):
+        return bool(self.path)
 
-        return default
+    def song(self):
+        try:
+            return Song(self.mpclient.find('file', self.path)[0])
+        except IndexError:
+            return Song({})
 
-    def expand_tags(self, str):
-        """Expands tags in form $tag in str."""
-        ret = str
-        ret = ret.replace('$title', self.title())    #to ensure that it is set to at least filename
-        for tag in self._data:
-            ret = ret.replace('$' + tag, unicode(self._data[tag]))
-        ret = ret.replace('$songdir', os.path.dirname(self.filepath()))
-        return ret
+class PlaylistEntryRef:
+    """This class stores a reference to a playlist entry instead of full
+       metadata to conserve memory. Song's tags can be accessed
+       as in Song, but it requires a call to MPD for each tag. """
+    id       = None
+    mpclient = None
+
+    def __init__(self, mpclient, id):
+        self.mpclient = mpclient
+        self.id       = id
+
+    def __getitem__(self, key):
+        return self.song()[key]
+
+    def __nonzero__(self):
+        return self.id != '-1'
 
+    def song(self):
+        try:
+            return Song(self.mpclient.playlistid(id)[0])
+        except IndexError:
+            return Song({})
diff --git a/nephilim/winMain.py b/nephilim/winMain.py
index 31ab17f..728db42 100644
--- a/nephilim/winMain.py
+++ b/nephilim/winMain.py
@@ -178,8 +178,8 @@ class winMain(QtGui.QMainWindow):
         state = self.mpclient.status()['state']
         state = 'playing' if state == 'play' else 'paused' if state == 'pause' else 'stopped'
         if song:
-            self.setWindowTitle('%s by %s - %s [%s]'%(song.title(), song.artist(), APPNAME, state))
-            self.__statuslabel.setText('%s by %s on %s [%s]'%(song.title(), song.artist(),song.album(), state))
+            self.setWindowTitle('%s by %s - %s [%s]'%(song['title'], song['artist'], APPNAME, state))
+            self.__statuslabel.setText('%s by %s on %s [%s]'%(song['title'], song['artist'],song['album'], state))
         else:
             self.setWindowTitle(APPNAME)
             self.__statuslabel.setText('')