import os, mimetypes, recode, events, cuesheet, mutagen

from config import config

class DirectoryEntry(object):
	'''Base class for directory entries.'''

	def __init__(self, path, isabs = False, track = None, metadata = {}):
		self.path = path
		self.track = track
		self.metadata = metadata

		if isabs:
			self.abs_path = path
		else:
			path_list = os.path.split(config.get('music_root')) + os.path.split(self.path)
			if '..' in path_list:
				raise Exception('Invalid path')

			self.abs_path = os.path.normpath(os.path.sep.join(path_list))

	def __cmp__(self, other):
		return cmp(self.path, other.path)

	def __lt__(self, other):
		return self.path < other.path

	def __str__(self):
		return '<a href="/files/{path}">{name}</a><br />'.format(path = self.path, name = os.path.basename(self.path))

	def json(self):
		return {'type': self.entry_type, 'name': self.path, 'track': self.track, 'metadata': self.metadata}

class Directory(DirectoryEntry):
	'''A directory entry inside a directory.'''

	entry_type = 'dir'

	def listdir(self):
		directories = []
		files = []

		for f in os.listdir(self.abs_path):
			abs_path = os.path.join(self.abs_path, f)
			rel_path = os.path.relpath(abs_path, config.get('music_root'))
			if os.path.isdir(abs_path):
				directories.append(Directory(rel_path))
			elif os.path.isfile(abs_path):
				if os.path.splitext(f)[1] == '.cue':
					cue = cuesheet.Cuesheet(abs_path)
					for t in cue.tracks:
						metadata = {}
						info = cue.info[0]
						if info.performer:
							metadata['artist'] = info.performer
						if info.title:
							metadata['album'] = info.title
						if t.title:
							metadata['title'] = t.title
						files.append(File(rel_path, track = t.track[0], metadata = metadata))
				else:
					metadata = {}
					tags = mutagen.File(abs_path) or []
					if isinstance(tags, mutagen.mp3.MP3):
						for id3, tn in (('TPE1', 'artist'), ('TALB', 'album'), ('TIT2', 'title')):
							if id3 in tags:
								metadata[tn] = tags[id3].text[0]
					else:
						for tn in ('artist', 'album', 'title'):
							if tn in tags:
								metadata[tn] = tags[tn][0].encode('utf-8')
					files.append(File(rel_path, metadata = metadata))
		return sorted(directories) + sorted(files)

class File(DirectoryEntry):
	'''A file entry inside a directory.'''

	entry_type = 'file'

	def send(self, environ, start_response):
		do_range = 'HTTP_RANGE' in environ
		if do_range:
			file_range = environ['HTTP_RANGE'].split('bytes=')[1]

		mime = mimetypes.guess_type(self.abs_path, strict = False)[0] or 'application/octet-stream'
		size = os.path.getsize(self.abs_path)
		if do_range:
			start, end = [int(x or 0) for x in file_range.split('-')]
			if end == 0:
				end = size-1

			write_out = start_response('206 Partial Content', [
				('Content-Type', mime),
				('Content-Range', 'bytes {start}-{end}/{size}'.format(start = start, end = end, size = size)),
				('Content-Length', str(end - start + 1))])

			f = open(self.abs_path, 'rb')
			f.seek(start)
			remaining = end-start+1
			s = f.read(min(remaining, 1024))
			while s:
				write_out(s)
				remaining -= len(s)
				s = f.read(min(remaining, 1024))
			return []
		
		start_response('200 OK', [
			('Content-Type', mime),
			('Content-Length', str(size))])
		return open(self.abs_path, 'rb')

	def get_cache_path(self):
		cache_path = os.path.join(config.get('cache_dir'), self.path)
		cache_path = os.path.splitext(cache_path)[0]
		if self.track:
			cache_path += '.' + self.track
		cache_path += '.ogg'
		return cache_path

	def get_cache_file(self):
		return File(self.get_cache_path(), True)

	def recode(self, decoder, encoder, sessionid = None):
		if self.track:
			cue = cuesheet.Cuesheet(self.abs_path)
			t = cue.tracks[int(self.track)-1]
			start_time = t.get_start_time()
			next = cue.get_next(t)
			if next:
				end_time = next.get_start_time()
			else:
				end_time = None
			path = os.path.join(os.path.dirname(self.abs_path), cue.info[0].file[0])
		else:
			path = self.abs_path
			start_time, end_time = None, None

		decoder = recode.decoders[decoder]()
		encoder = recode.encoders[encoder]()
		recoder = recode.Recoder(decoder, encoder)

		cache_path = self.get_cache_path()
		cache_path_dir = os.path.dirname(cache_path)
		# check and create cache directory
		if not os.path.exists(cache_path_dir):
			os.makedirs(cache_path_dir)
		# check if file is cached
		if not os.path.exists(cache_path):
			events.event_pub.recoding(self.path, self.track)
			recoder.recode(path, cache_path, start_time = start_time, end_time = end_time)
		events.event_pub.cached(self.path, self.track)

		if sessionid:
			events.event_pub.play(sessionid, '/cache/{0}'.format(self.path))

	def start_recode(self, decoder, encoder, sessionid = None):
		recode.RecodeThread.add((self.recode, decoder, encoder, sessionid))

	def json(self):
		cache_path = self.get_cache_path()
		d = DirectoryEntry.json(self)
		d.update({'cached': os.path.exists(cache_path)})
		return d