#!/usr/bin/env python

import argparse
import contextlib
import sys

import mammoth


def main():
    args = _parse_args()
    
    if args.styles is None:
        styles = None
    else:
        with open(args.styles) as styles_fileobj:
            styles = styles_fileobj.read()
    
    with _open_output(args.output) as output:
        with open(args.path, "rb") as docx_fileobj:
            result = mammoth.convert_to_html(docx_fileobj, styles=styles)
            for message in result.messages:
                sys.stderr.write(message.message)
                sys.stderr.write("\n")
            output.write(result.value.encode("utf8"))


@contextlib.contextmanager
def _open_output(name):
    if name is None:
        try:
            yield sys.stdout
        finally:
            sys.stdout.flush()
    else:
        with open(name, "w") as output:
            yield output


def _parse_args():
    parser = argparse.ArgumentParser()
    parser.add_argument("path")
    parser.add_argument("output", nargs="?")
    parser.add_argument("--styles", required=False)
    return parser.parse_args()


if __name__ == "__main__":
    main()