nephilim/song.py

   1 #
   2 #    Copyright (C) 2009 Anton Khirnov <wyskas@gmail.com>
   3 #
   4 #    Nephilim is free software: you can redistribute it and/or modify
   5 #    it under the terms of the GNU General Public License as published by
   6 #    the Free Software Foundation, either version 3 of the License, or
   7 #    (at your option) any later version.
   8 #
   9 #    Nephilim is distributed in the hope that it will be useful,
  10 #    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 #    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12 #    GNU General Public License for more details.
  13 #
  14 #    You should have received a copy of the GNU General Public License
  15 #    along with Nephilim.  If not, see <http://www.gnu.org/licenses/>.
  16 #
  17
  18 from PyQt4 import QtCore
  19 import os
  20
  21 from common import sec2min
  22
  23 class Song(dict):
  24     """Song provides a dictionary-like wrapper around song metadata.
  25        Its instances _shouldn't_ be stored, use SongRef or PlaylistEntryRef for that.
  26        Access '?tag' to get always at least an empty string. """
  27
  28     def __init__(self, data):
  29         for tag in data:
  30             if isinstance(data[tag], list):
  31                 data[tag] = ','.join(data[tag])
  32
  33         dict.__init__(self, data)
  34
  35     def __eq__(self, other):
  36         if not isinstance(other, Song):
  37             return NotImplemented
  38         return self['file'] == other['file']
  39
  40     def __ne__(self, other):
  41         if not isinstance(other, Song):
  42             return NotImplemented
  43         return self['file'] != other['file']
  44
  45     def __getitem__(self, key):
  46         try:
  47             return dict.__getitem__(self, key)
  48         except KeyError:
  49             if key and key[0] == '?':
  50                 key = key[1:]
  51                 return self[key] if key in self else ''
  52             if key == 'tracknum':
  53                 try:
  54                     return int(self['track'])
  55                 except ValueError:
  56                     try:
  57                         return int(self['track'].split('/')[0])
  58                     except ValueError:
  59                         return 0
  60             elif key == 'length':
  61                 return sec2min(int(self['time']))
  62             elif key == 'id':
  63                 return '-1'
  64             elif key == 'title':
  65                 return self['file']
  66             elif key == 'albumartist':
  67                 return self['artist']
  68             return ''
  69
  70     def __contains__(self, item):
  71         if dict.__contains__(self, item):
  72             return True
  73         try:
  74             self[item]
  75             return True
  76         except KeyError:
  77             return False
  78
  79     def __nonzero__(self):
  80         return bool(self['file'])
  81
  82     def expand_tags(self, str):
  83         """Expands tags in form $tag in str."""
  84         ret = str
  85         ret = ret.replace('$title', self['title'])    #to ensure that it is set to at least filename
  86         for tag in self.keys() + ['tracknum', 'length', 'id']:
  87             ret = ret.replace('$' + tag, unicode(self[tag]))
  88         ret = ret.replace('$songdir', os.path.dirname(self['file']))
  89         return ret
  90
  91 class SongRef:
  92     """SongRef stores only a reference to the song (uri) instead
  93        of full metadata to conserve memory. Song's tags can be accessed
  94        as in Song, but it requires a call to MPD for each tag. """
  95     path     = None
  96     mpclient = None
  97
  98     def __init__(self, mpclient, path):
  99         self.mpclient = mpclient
 100         self.path     = path
 101
 102     def __getitem__(self, key):
 103         return self.song()[key]
 104
 105     def __nonzero__(self):
 106         return bool(self.path)
 107
 108     def song(self):
 109         try:
 110             return Song(self.mpclient.find('file', self.path)[0])
 111         except IndexError:
 112             return Song({})
 113
 114 class PlaylistEntryRef:
 115     """This class stores a reference to a playlist entry instead of full
 116        metadata to conserve memory. Song's tags can be accessed
 117        as in Song, but it requires a call to MPD for each tag. """
 118     plid       = None
 119     mpclient = None
 120
 121     def __init__(self, mpclient, plid):
 122         self.mpclient = mpclient
 123         self.plid       = plid
 124
 125     def __getitem__(self, key):
 126         return self.plid if key == 'id' else self.song()[key]
 127
 128     def __nonzero__(self):
 129         return self.plid != '-1'
 130
 131     def song(self):
 132         try:
 133             return self.mpclient.playlistid(self.plid)
 134         except IndexError:
 135             return Song({})