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
  27     def __init__(self, data):
  28         # decode all strings to unicode
  29         for tag in data:
  30             if isinstance(data[tag], list):
  31                 data[tag] = ','.join(data[tag])
  32             if isinstance(data[tag], str):
  33                 data[tag] = data[tag].decode('utf-8')
  34
  35         dict.__init__(self, data)
  36
  37     def __eq__(self, other):
  38         if not isinstance(other, Song):
  39             return NotImplemented
  40         return self['file'] == other['file']
  41
  42     def __ne__(self, other):
  43         if not isinstance(other, Song):
  44             return NotImplemented
  45         return self['file'] != other['file']
  46
  47     def __getitem__(self, key):
  48         try:
  49             return dict.__getitem__(self, key)
  50         except KeyError:
  51             if key == 'tracknum':
  52                 try:
  53                     return int(self['track'])
  54                 except ValueError:
  55                     try:
  56                         return int(self['track'].split('/')[0])
  57                     except ValueError:
  58                         return 0
  59             elif key == 'length':
  60                 return sec2min(int(self['time']))
  61             elif key == 'id':
  62                 return '-1'
  63             elif key == 'title':
  64                 return self['file']
  65             elif key == 'albumartist':
  66                 return self['artist']
  67             return ''
  68
  69     def __nonzero__(self):
  70         return bool(self['file'])
  71
  72     def expand_tags(self, str):
  73         """Expands tags in form $tag in str."""
  74         ret = str
  75         ret = ret.replace('$title', self['title'])    #to ensure that it is set to at least filename
  76         for tag in self.keys() + ['tracknum', 'length', 'id']:
  77             ret = ret.replace('$' + tag, unicode(self[tag]))
  78         ret = ret.replace('$songdir', os.path.dirname(self['file']))
  79         return ret
  80
  81 class SongRef:
  82     """SongRef stores only a reference to the song (uri) instead
  83        of full metadata to conserve memory. Song's tags can be accessed
  84        as in Song, but it requires a call to MPD for each tag. """
  85     path     = None
  86     mpclient = None
  87
  88     def __init__(self, mpclient, path):
  89         self.mpclient = mpclient
  90         self.path     = path
  91
  92     def __getitem__(self, key):
  93         return self.song()[key]
  94
  95     def __nonzero__(self):
  96         return bool(self.path)
  97
  98     def song(self):
  99         try:
 100             return Song(self.mpclient.find('file', self.path)[0])
 101         except IndexError:
 102             return Song({})
 103
 104 class PlaylistEntryRef:
 105     """This class stores a reference to a playlist entry instead of full
 106        metadata to conserve memory. Song's tags can be accessed
 107        as in Song, but it requires a call to MPD for each tag. """
 108     id       = None
 109     mpclient = None
 110
 111     def __init__(self, mpclient, id):
 112         self.mpclient = mpclient
 113         self.id       = id
 114
 115     def __getitem__(self, key):
 116         return self.song()[key]
 117
 118     def __nonzero__(self):
 119         return self.id != '-1'
 120
 121     def song(self):
 122         try:
 123             return Song(self.mpclient.playlistid(id)[0])
 124         except IndexError:
 125             return Song({})