#!/usr/bin/python
# Transcode my music collection into an ogg version suitable for portable
# devices.

import os, sys, re, subprocess, getopt

music = "/n/stuff/music"
source_dirs = [
	music + "/cds",
	music + "/lps",
	music + "/tapes",
	"/home/ats/Work/music/recorded",
	]
exclude_res = [
	re.compile(r'/raw/'),
	]
dest_dir = music + "/ogg"
transcode_exts = [".flac", ".wav"]
lossy_exts = [".mp3", ".ogg"]
oggenc_args = ["-q5"]

dryrun = False
lint = False

def run_command(cmd):
	if dryrun:
		print "Would run: %s" % (" ".join(cmd))
		return

	rc = subprocess.call(cmd)
	if rc != 0:
		print "Command failed with rc %d: %s" % (rc, " ".join(cmd))
		sys.exit(rc)

def clean_fn(fn):
	"""Replace characters that aren't legal in VFAT long filenames."""
	fn = fn.replace(":", " -")
	fn = re.sub(r'["*<>?\\|\000-\037\177-\377]', '_', fn)
	return fn

def sync_dir(src, base, files, seen):
	dest = dest_dir + clean_fn(base)

	has_lossy = False
	has_lossless = False
	for fn in files:
		if any([fn.endswith(ext) for ext in lossy_exts]):
			has_lossy = True
			continue
		base_fn = None
		for ext in transcode_exts:
			if fn.endswith(ext):
				base_fn = fn[:-len(ext)]
		if base_fn is None:
			continue
		has_lossless = True

		src_fn = src + "/" + fn
		excluded = False
		for exp in exclude_res:
			if exp.search(src_fn) is not None:
				excluded = True
		if excluded:
			continue

		dest_fn = dest + "/" + clean_fn(base_fn) + ".ogg"
		seen.add(dest_fn)

		if os.access(dest_fn, os.F_OK):
			continue

		print "Transcode %s to %s" % (src_fn, dest_fn)

		try:
			if not dryrun:
				os.makedirs(dest)
		except OSError:
			pass

		run_command(["oggenc", "-Q", "-o", dest_fn] + oggenc_args + [src_fn])

	if lint and has_lossy:
		if has_lossless:
			print "Contains both lossy and lossless files: %s" % src
		else:
			print "Contains lossy files: %s" % src

def clean_dir(dest, files, seen):
	for fn in files:
		dest_fn = dest + "/" + fn
		if not dest_fn in seen:
			print "Remove %s" % dest_fn
			if not dryrun:
				os.unlink(dest_fn)

	if os.listdir(dest) == []:
		print "Remove dir %s" % dest
		if not dryrun:
			os.rmdir(dest)

def main(args):
	try:
		opts, args = getopt.getopt(args, "nl", [])
	except getopt.GetoptError:
		print "Usage: transcode-music [-n] [-l]"
		sys.exit(1)

	global dryrun, lint
	for o, a in opts:
		if o == "-n":
			dryrun = True
		elif o == "-l":
			lint = True

	seen = set()

	for dir in source_dirs:
		for src, dirs, files in os.walk(dir, topdown = True):
			sync_dir(src, src[len(dir):], files, seen)

	for dest, dirs, files in os.walk(dest_dir, topdown = False):
		clean_dir(dest, files, seen)

if __name__ == "__main__":
	main(sys.argv[1:])