from config import config
from sqlalchemy import create_engine
engine = create_engine(config.get('db_path'))

from sqlalchemy.ext.declarative import declarative_base
Base = declarative_base()

from sqlalchemy import Column, Integer, String, ForeignKey
from sqlalchemy.orm import relationship, backref
from sqlalchemy import and_

from sqlalchemy.orm.exc import NoResultFound

class Directory(Base):
	__tablename__ = 'directories'

	id = Column(Integer, primary_key = True)
	path = Column(String, nullable = False, index = True)
	parent_id = Column(Integer, ForeignKey('directories.id'))

	parent = relationship('Directory')

	def __init__(self, path):
		self.path = path

	def __repr__(self):
		return '<Directory("{0}")>'.format(self.path)

	@staticmethod
	def get(session, path):
		try:
			directory = session.query(Directory).filter(Directory.path == path).one()
		except NoResultFound:
			directory = Directory(path)
			session.add(directory)
			session.commit()
		return directory

class Artist(Base):
	__tablename__ = 'artists'

	id = Column(Integer, primary_key = True)
	name = Column(String, nullable = False, index = True)

	def __init__(self, name):
		self.name = name

	def __repr__(self):
		return '<Artist("{0}")>'.format(self.name.encode('utf-8'))

	@staticmethod
	def get(session, name):
		try:
			artist = session.query(Artist).filter(Artist.name == name).one()
		except NoResultFound:
			artist = Artist(name)
			session.add(artist)
			session.commit()
		return artist

class Album(Base):
	__tablename__ = 'albums'

	id = Column(Integer, primary_key = True)
	name = Column(String, nullable = False, index = True)
	artist_id = Column(Integer, ForeignKey('artists.id'), nullable = False)

	artist = relationship(Artist, backref = backref('albums', order_by = name))

	def __init__(self, name, artist_id):
		self.name = name
		self.artist_id = artist_id

	def __repr__(self):
		return '<Album("{0}")>'.format(self.name)

	@staticmethod
	def get(session, name, artist_id = None):
		try:
			album = session.query(Album).filter(Album.name == name).one()
		except NoResultFound:
			album = Album(name, artist_id)
			session.add(album)
			session.commit()
		return album

class Track(Base):
	__tablename__ = 'tracks'

	id = Column(Integer, primary_key = True)
	name = Column(String, index = True)
	num = Column(Integer)
	filename = Column(String, nullable = False, index = True)
	file_index = Column(Integer)
	directory_id = Column(Integer, ForeignKey('directories.id'), nullable = False)
	artist_id = Column(Integer, ForeignKey('artists.id'))
	album_id = Column(Integer, ForeignKey('albums.id'))

	directory = relationship(Directory, backref = backref('tracks', order_by = filename))

	def __init__(self, name, num, filename, file_index, directory_id, artist_id, album_id):
		self.name = name
		self.num = num
		self.filename = filename
		self.file_index = file_index
		self.directory_id = directory_id
		self.artist_id = artist_id
		self.album_id = album_id

	def __repr__(self):
		return u'<Track("{0}")>'.format(self.name)

	@staticmethod
	def get(session, name, num, filename, file_index, directory_id, artist_id, album_id):
		try:
			track = session.query(Track).filter(and_(Track.filename == filename, Track.file_index == file_index)).one()
		except NoResultFound:
			track = Track(name, num, filename, file_index, directory_id, artist_id, album_id)
			session.add(track)
		return track

Base.metadata.create_all(engine)

from sqlalchemy.orm import sessionmaker
Session = sessionmaker(bind = engine)