#!/usr/bin/env python
# -*- coding: utf-8 -*-
#
# Find all *.{mp3,ogg,flac} files under given directory and add empty ID3 header
# to raw MPEG Layer 3 streams.
#
# $LastChangedDate$
# 
# Copyright (C) 2007 by Timur Izhbulatov <timochka@gmail.com>
# 
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published
# by the Free Software Foundation; version 2 only.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.

import sys
import os

def error(message):
    print >> sys.stderr, str(message)

try:
    import mutagen
    import mutagen.id3
except ImportError:
    error('This script requires mutagen but it could not be found\n'
          'Please run "easy_install mutagen"\n')
    sys.exit(1)


def main():
    if len(sys.argv) != 2:
        usage()

    dirname = sys.argv.pop()
    try:
        # Make directory tree generator
        tree_gen = os.walk(dirname)
    except OSError, e:
        error('Error opening directory "%s": %s' % (dirname, e))

    for dirpath, dirnames, filenames in tree_gen:
        for filename in filenames:
            # Work only with *.{mp3,ogg,flac} files
            if os.path.splitext(filename)[1].lower() not in ('.mp3', '.ogg', '.flac'):
                continue
            try:
                path_to_file = os.path.join(dirpath, filename)
                # mutagen.File tries to detect file type automatically
                ftype = mutagen.File(path_to_file)
                try:
                    ftype.add_tags()    
                except NotImplementedError, e:
                    error('Failed to detect file type of "%s". Skipping.' % filename)
                    continue
                ftype.save()
            except (mutagen.id3.error, IOError, OSError), e:
                # Tags already exist, read error
                error('Error processing "%s": %s. Skipping.' % (filename, e))

def usage():
    message = (
       'Find all *.{mp3,ogg,flac} files under given directory and add empty ID3 header\n'
       'to raw MPEG Layer 3 streams.\n'
       'Usage:\n'
       '%s <dirname>\n'
       'Author: Timur Izhbulatov <TimurIzhbulatov@gmail.com>\n'
       '$LastChangedDate: 2007-11-10 02:36:50 +0300 (Сбт, 10 Ноя 2007)$\n'
       ) % sys.argv[0]
    error(message)
    sys.exit(1)

if __name__ == '__main__':
    main()