#!/usr/bin/python

"""usage: fix-po-encodings [filename...]

change the encoding of the po files passed as arguments to utf-8

"""

import sys

import re

import codecs

def change_encoding(filename, target='UTF-8'):

    fdesc = open(filename)

    data = fdesc.read()

    fdesc.close()

    encoding = find_encoding(data)

    if encoding == target:

        return

    data = fix_encoding(data, target)

    data = unicode(data, encoding)

    fdesc = codecs.open(filename, 'wb', encoding=target)

    fdesc.write(data)

    fdesc.close()

def find_encoding(data):

    regexp = re.compile(r'"Content-Type:.* charset=([a-zA-Z0-9-]+)\\n"', re.M)

    mo = regexp.search(data)

    if mo is None:

        raise ValueError('No encoding declaration')

    return mo.group(1)

def fix_encoding(data, target_encoding):

    regexp = re.compile(r'("Content-Type:.* charset=)(.*)(\\n")', re.M)

    return regexp.sub(r'\1%s\3' % target_encoding, data)

for filename in sys.argv[1:]:

    print filename

    change_encoding(filename)