#!/usr/bin/python
#
# minimify -- compress file to smallest size
# Copyright (C) 2009  Lars Wirzenius
#
# 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, either version 3 of the License, or
# (at your option) any later version.
#
# 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.
#
# You should have received a copy of the GNU General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.


import multiprocessing
import optparse
import os
import subprocess
import tempfile


COMPRESSORS = (
    ('gzip', '.gz'),
    ('bzip2', '.bz2'),
    ('xz', '.xz'),
)


def parse_args():
    parser = optparse.OptionParser()
    options, filenames = parser.parse_args()
    return options, filenames


def run_compressor(t):
    compressor, filename, suffix, options = t
    input_f = file(filename)
    fd, name = tempfile.mkstemp(dir=os.path.dirname(filename))
    p = subprocess.Popen([compressor], stdin=input_f, stdout=fd)
    p.communicate('')
    os.close(fd)
    if p.returncode:
        raise Exception('Compression program %s failed' % p.returncode)
    os.rename(name, filename + suffix)
    return os.path.getsize(filename + suffix), filename + suffix


def compress(filename, options):
    args = [(compressor, filename, suffix, options)
            for compressor, suffix in COMPRESSORS]
    pool = multiprocessing.Pool()
    sizes = sorted(pool.map(run_compressor, args))
    for size, pathname in sizes[1:]:
        os.remove(pathname)
    return sizes[0]


def main():
    options, filenames = parse_args()
    for filename in filenames:
        size, name = compress(filename, options)
        print size, name


if __name__ == "__main__":
    main()