from light9.showconfig import getSongsFromShow, songOnDisk

from light9.namespaces import L9

from rdflib import URIRef

class NoSuchSong(ValueError):

    """Raised when a song is requested that doesn't exist (e.g. one

    after the last song in the playlist)."""

class Playlist(object):

    def __init__(self, graph, playlistUri):

        self.graph = graph

        # this should be fixed to share with getSongsFromShow. See note in that one for why I had to stop using graph.items

        self.songs = [

            URIRef("http://light9.bigasterisk.com/show/dance2013/song1"),

            URIRef("http://light9.bigasterisk.com/show/dance2013/song2"),

            URIRef("http://light9.bigasterisk.com/show/dance2013/song3"),

            URIRef("http://light9.bigasterisk.com/show/dance2013/song4"),

            URIRef("http://light9.bigasterisk.com/show/dance2013/song5"),

            URIRef("http://light9.bigasterisk.com/show/dance2013/song6"),

            URIRef("http://light9.bigasterisk.com/show/dance2013/song7"),

            URIRef("http://light9.bigasterisk.com/show/dance2013/song8"),

            URIRef("http://light9.bigasterisk.com/show/dance2013/song9"),

            URIRef("http://light9.bigasterisk.com/show/dance2013/song10"),

            URIRef("http://light9.bigasterisk.com/show/dance2013/song11"),

            URIRef("http://light9.bigasterisk.com/show/dance2013/song12"),

            URIRef("http://light9.bigasterisk.com/show/dance2013/song13"),

            URIRef("http://light9.bigasterisk.com/show/dance2013/song14"),

            URIRef("http://light9.bigasterisk.com/show/dance2013/song15"),

            URIRef("http://light9.bigasterisk.com/show/dance2013/song16"),

            URIRef("http://light9.bigasterisk.com/show/dance2013/song17"),

        ]

    def nextSong(self, currentSong):

        """Returns the next song in the playlist or raises NoSuchSong if 

        we are at the end of the playlist."""

        try:

            currentIndex = self.songs.index(currentSong)

        except IndexError:

            raise ValueError("%r is not in the current playlist (%r)." % \

                (currentSong, self.playlistUri))

        try:

            nextSong = self.songs[currentIndex + 1]

        except IndexError:

            raise NoSuchSong("%r is the last item in the playlist." % \

                             currentSong)

        return nextSong

    def allSongs(self):

        """Returns a list of all song URIs in order."""

        return self.songs

    def allSongPaths(self):

        """Returns a list of the filesystem paths to all songs in order."""

        paths = []

        for song in self.songs:

            paths.append(songOnDisk(song))

        return paths

    def songPath(self, uri):

        """filesystem path to a song"""

        raise NotImplementedError("see showconfig.songOnDisk")

        # maybe that function should be moved to this method

    @classmethod

    def fromShow(playlistClass, graph, show):

        playlistUri = graph.value(show, L9['playList'])

        if not playlistUri:

            raise ValueError("%r has no l9:playList" % show)

        return playlistClass(graph, playlistUri)

def songOnDisk(song):

    """given a song URI, where's the on-disk file that mpd would read?"""

    graph = getGraph()

    root = graph.value(showUri(), L9['musicRoot'])

    if not root:

        raise ValueError("%s has no :musicRoot" % showUri())

    name = graph.value(song, L9['songFilename'])

    if not name:

        raise ValueError("Song %r has no :songFilename" % song)

    return path.abspath(path.join(root, name))

def songFilenameFromURI(uri):

    """

    'http://light9.bigasterisk.com/show/dance2007/song8' -> 'song8'

    everything that uses this should be deprecated for real URIs

    everywhere"""

    assert isinstance(uri, URIRef)

    return uri.split('/')[-1]

def getSongsFromShow(graph, show):

    playList = graph.value(show, L9['playList'])

    if not playList:

        raise ValueError("%r has no l9:playList" % show)

    songs = [

        # this was graph.items(playlistUri) but i was getting other

        # items from a totally different list! seems like bnode

        # corruption.

        URIRef("http://light9.bigasterisk.com/show/dance2013/song1"),

        URIRef("http://light9.bigasterisk.com/show/dance2013/song2"),

        URIRef("http://light9.bigasterisk.com/show/dance2013/song3"),

        URIRef("http://light9.bigasterisk.com/show/dance2013/song4"),

        URIRef("http://light9.bigasterisk.com/show/dance2013/song5"),

        URIRef("http://light9.bigasterisk.com/show/dance2013/song6"),

        URIRef("http://light9.bigasterisk.com/show/dance2013/song7"),

        URIRef("http://light9.bigasterisk.com/show/dance2013/song8"),

        URIRef("http://light9.bigasterisk.com/show/dance2013/song9"),

        URIRef("http://light9.bigasterisk.com/show/dance2013/song10"),

        URIRef("http://light9.bigasterisk.com/show/dance2013/song11"),

        URIRef("http://light9.bigasterisk.com/show/dance2013/song12"),

        URIRef("http://light9.bigasterisk.com/show/dance2013/song13"),

        URIRef("http://light9.bigasterisk.com/show/dance2013/song14"),

        URIRef("http://light9.bigasterisk.com/show/dance2013/song15"),

        URIRef("http://light9.bigasterisk.com/show/dance2013/song16"),

        URIRef("http://light9.bigasterisk.com/show/dance2013/song17"),

    ]

    return songs

def curvesDir():

    return path.join(root(),"curves")

def songFilename(song):

    return path.join(root(), "music", "%s.wav" % song)

def subtermsForSong(song):

    return path.join(root(),"subterms",song)

def subFile(subname):

    return path.join(root(),"subs",subname)

def subsDir():

    return path.join(root(),'subs')

def prePostSong():

    graph = getGraph()

    return [graph.value(MUS['preSong'], L9['showPath']),

            graph.value(MUS['postSong'], L9['showPath'])]