import subprocess, tempfile, threading

decoders = {}
encoders = {}

class DecoderMeta(type):
	def __init__(cls, name, bases, dict):
		if not name in ('Decoder', 'Codec'):
			decoders[cls.decoder_name] = cls

class Decoder(object):
	__metaclass__ = DecoderMeta

class EncoderMeta(type):
	def __init__(cls, name, bases, dict):
		if not name in ('Encoder', 'Codec'):
			encoders[cls.encoder_name] = cls

class Encoder(object):
	__metaclass__ = EncoderMeta

class CodecMeta(DecoderMeta, EncoderMeta):
	def __init__(cls, name, bases, dict):
		DecoderMeta.__init__(cls, name, bases, dict)
		EncoderMeta.__init__(cls, name, bases, dict)

class Codec(object):
	__metaclass__ = CodecMeta

# end of metastuff

class FFmpeg(Codec):
	decoder_name = 'ffmpeg'
	encoder_name = 'ffmpeg'

	def decode(self, source, dest, *args):
		ret = subprocess.call((x.format(infile = source, outfile = dest) for x in 'ffmpeg -loglevel quiet -i {infile} -y {outfile}'.split()))
		print 'decoding returned', ret

	def encode(self, source, dest, *args):
		ret = subprocess.call((x.format(infile = source, outfile = dest) for x in 'ffmpeg -loglevel quiet -i {infile} -y {outfile}'.split()))
		print 'encoding returned', ret

	def recode(self, source, dest, *args):
		ret = subprocess.call((x.format(infile = source, outfile = dest) for x in 'ffmpeg -loglevel quiet -i {infile} -y {outfile}'.split()))
		print 'recoding returned', ret

class Recoder(object):
	def __init__(self, decoder, encoder):
		self.decoder = decoder
		self.encoder = encoder

	def recode(self, source, dest):
		if self.decoder.__class__ == self.encoder.__class__ and hasattr(self.decoder, 'recode'):
			print 'recoding'
			print self.decoder
			self.decoder.recode(source, dest)
		else:
			temp = tempfile.NamedTemporaryFile(mode = 'wb', prefix = 'foo', suffix = os.path.splitext(dest)[1], delete = True)
			print 'decoding'
			self.decoder.decode(source, temp.name)
			print 'encoding'
			self.encoder.encode(temp.name, dest)
			temp.close()

class RecodeThread(threading.Thread):
	lock = threading.Lock()
	queue = []
	running = False

	def get_job(self):
		return self.queue.pop(0) if len(self.queue) else None

	def run(self):
		self.lock.acquire()
		job = self.get_job()
		while job:
			self.lock.release()

			func, decoder, encoder, sessionid = job
			func(decoder, encoder, sessionid)

			self.lock.acquire()
			job = self.get_job()

		RecodeThread.running = False
		self.lock.release()

	@classmethod
	def add(cls, job):
		cls.lock.acquire()
		cls.queue.append(job)
		if not cls.running:
			cls.running = True
			RecodeThread().start()
		cls.lock.release()

if __name__ == '__main__':
	import sys
	ffmpeg = FFmpeg()
	print ffmpeg
	r = Recoder(ffmpeg, ffmpeg)
	r.recode(sys.argv[1], sys.argv[2])