mopidy/mopidy/backends/despotify.py

import datetime as dt
import logging
import sys

import spytify

from mopidy import settings
from mopidy.backends import (BaseBackend, BaseCurrentPlaylistController,
    BaseLibraryController, BasePlaybackController,
    BaseStoredPlaylistsController)
from mopidy.models import Artist, Album, Track, Playlist

logger = logging.getLogger('mopidy.backends.despotify')

ENCODING = 'utf-8'

class DespotifyBackend(BaseBackend):
    """
    A Spotify backend which uses the open source `despotify library
    <http://despotify.se/>`_.

    `spytify <http://despotify.svn.sourceforge.net/viewvc/despotify/src/bindings/python/>`_
    is the Python bindings for the despotify library. It got litle
    documentation, but a couple of examples are available.

    **Issues:** http://github.com/jodal/mopidy/issues/labels/backend-despotify
    """

    def __init__(self, *args, **kwargs):
        super(DespotifyBackend, self).__init__(*args, **kwargs)
        self.current_playlist = DespotifyCurrentPlaylistController(backend=self)
        self.library = DespotifyLibraryController(backend=self)
        self.playback = DespotifyPlaybackController(backend=self)
        self.stored_playlists = DespotifyStoredPlaylistsController(backend=self)
        self.uri_handlers = [u'spotify:', u'http://open.spotify.com/']
        self.spotify = self._connect()
        self.stored_playlists.refresh()

    def _connect(self):
        logger.info(u'Connecting to Spotify')
        try:
            return DespotifySessionManager(
                settings.SPOTIFY_USERNAME.encode(ENCODING),
                settings.SPOTIFY_PASSWORD.encode(ENCODING),
                core_queue=self.core_queue)
        except spytify.SpytifyError as e:
            logger.exception(e)
            sys.exit(1)


class DespotifyCurrentPlaylistController(BaseCurrentPlaylistController):
    pass


class DespotifyLibraryController(BaseLibraryController):
    def find_exact(self, **query):
        return self.search(**query)

    def lookup(self, uri):
        track = self.backend.spotify.lookup(uri.encode(ENCODING))
        return DespotifyTranslator.to_mopidy_track(track)

    def search(self, **query):
        spotify_query = []
        for (field, values) in query.iteritems():
            if not hasattr(values, '__iter__'):
                values = [values]
            for value in values:
                if field == u'track':
                    field = u'title'
                if field is u'any':
                    spotify_query.append(value)
                else:
                    spotify_query.append(u'%s:"%s"' % (field, value))
        spotify_query = u' '.join(query)
        result = self.backend.spotify.search(spotify_query.encode(ENCODING))
        if (result is None or result.playlist.tracks[0].get_uri() ==
                'spotify:track:0000000000000000000000'):
            return Playlist()
        return DespotifyTranslator.to_mopidy_playlist(result.playlist)


class DespotifyPlaybackController(BasePlaybackController):
    def _pause(self):
        try:
            self.backend.spotify.pause()
            return True
        except spytify.SpytifyError as e:
            logger.error(e)
            return False

    def _play(self, track):
        try:
            self.backend.spotify.play(self.backend.spotify.lookup(track.uri))
            return True
        except spytify.SpytifyError as e:
            logger.error(e)
            return False

    def _resume(self):
        try:
            self.backend.spotify.resume()
            return True
        except spytify.SpytifyError as e:
            logger.error(e)
            return False

    def _stop(self):
        try:
            self.backend.spotify.stop()
            return True
        except spytify.SpytifyError as e:
            logger.error(e)
            return False


class DespotifyStoredPlaylistsController(BaseStoredPlaylistsController):
    def refresh(self):
        logger.info(u'Caching stored playlists')
        playlists = []
        for spotify_playlist in self.backend.spotify.stored_playlists:
            playlists.append(
                DespotifyTranslator.to_mopidy_playlist(spotify_playlist))
        self._playlists = playlists
        logger.debug(u'Available playlists: %s',
            u', '.join([u'<%s>' % p.name for p in self.playlists]))
        logger.info(u'Done caching stored playlists')


class DespotifyTranslator(object):
    @classmethod
    def to_mopidy_artist(cls, spotify_artist):
        return Artist(
            uri=spotify_artist.get_uri(),
            name=spotify_artist.name.decode(ENCODING)
        )

    @classmethod
    def to_mopidy_album(cls, spotify_album_name):
        return Album(name=spotify_album_name.decode(ENCODING))

    @classmethod
    def to_mopidy_track(cls, spotify_track):
        if spotify_track is None or not spotify_track.has_meta_data():
            return None
        if dt.MINYEAR <= int(spotify_track.year) <= dt.MAXYEAR:
            date = dt.date(spotify_track.year, 1, 1)
        else:
            date = None
        return Track(
            uri=spotify_track.get_uri(),
            name=spotify_track.title.decode(ENCODING),
            artists=[cls.to_mopidy_artist(a) for a in spotify_track.artists],
            album=cls.to_mopidy_album(spotify_track.album),
            track_no=spotify_track.tracknumber,
            date=date,
            length=spotify_track.length,
            bitrate=320,
        )

    @classmethod
    def to_mopidy_playlist(cls, spotify_playlist):
        return Playlist(
            uri=spotify_playlist.get_uri(),
            name=spotify_playlist.name.decode(ENCODING),
            tracks=filter(None,
                [cls.to_mopidy_track(t) for t in spotify_playlist.tracks]),
        )


class DespotifySessionManager(spytify.Spytify):
    DESPOTIFY_NEW_TRACK = 1
    DESPOTIFY_TIME_TELL = 2
    DESPOTIFY_END_OF_PLAYLIST = 3
    DESPOTIFY_TRACK_PLAY_ERROR = 4

    def __init__(self, *args, **kwargs):
        kwargs['callback'] = self.callback
        self.core_queue = kwargs.pop('core_queue')
        super(DespotifySessionManager, self).__init__(*args, **kwargs)

    def callback(self, signal, data):
        if signal == self.DESPOTIFY_END_OF_PLAYLIST:
            logger.debug('Despotify signalled end of playlist')
            self.core_queue.put({'command': 'end_of_track'})
        elif signal == self.DESPOTIFY_TRACK_PLAY_ERROR:
            logger.error('Despotify signalled track play error')