#!/usr/bin/env python
# -*- coding: utf-8 -*-
##=============================================================================
 #
 # Copyright (C) 2003, 2011 Alessandro Duca <alessandro.duca@gmail.com>
 #
 # This library is free software; you can redistribute it and/or
 # modify it under the terms of the GNU Lesser General Public
 # License as published by the Free Software Foundation; either
 # version 2.1 of the License, or (at your option) any later version.
 #
 # This library 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
 # Lesser General Public License for more details.
 #
 # You should have received a copy of the GNU Lesser General Public
 # License along with this library; if not, write to the Free Software
 # Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
 #=============================================================================
 # 
##=============================================================================

import sys
import os
import os.path
import yenc
import getopt
from stat import *
from binascii import crc32

def main():
    try:
        opts, args = getopt.getopt(sys.argv[1:], "o:")
    except getopt.GetoptError:
        usage()
    try:  # Python 3
        file_out = sys.stdout.buffer
    except AttributeError:  # Python < 3
        file_out = sys.stdout
    for o,a in opts:
        if o == '-o':
            file_out = open(a,"wb")
    if args:
        filename = args[0]
        if not os.access( filename, os.F_OK | os.R_OK ):
            sys.stderr.write("couldn't access %s\n" % filename)
            sys.exit(2)
    else:
        usage()
    with open(filename,"rb") as file_in:
        crc = "%x"%(0xFFFFFFFF & crc32(file_in.read()))
    name = os.path.split(filename)[1]
    size = os.stat(filename)[ST_SIZE]
    line = "=ybegin line=128 size=%d crc32=%s name=%s\r\n"
    file_out.write((line % (size, crc, name)).encode("ascii"))
    with open(filename, "rb") as file_in:
        encoder = yenc.Encoder(file_out)
        while True:
            data_in = file_in.read(1024)
            encoder.feed(data_in)
            encoder.flush()
            if len(data_in) < 1024: break
    encoder.terminate()
    encoder.flush()
    line = "=yend size=%d crc32=%s\r\n" % (size, encoder.getCrc32())
    file_out.write(line.encode("ascii"))

def usage():
    sys.stderr.write("Usage: yencode_Encoder.py <-o outfile> filename\n")
    sys.exit(1)

if __name__ == "__main__":
    main()