Write gophermap files easily and naturally

gophmt.py

#!/usr/bin/env python
# -*- coding: utf-8 -*-
import argparse
import sys
import textwrap
try:
    from cStringIO import StringIO
except ImportError:
    from StringIO import StringIO


def process(infile, outfile, width, delimiter):
    wrapper = textwrap.TextWrapper(width=width)
    buf = StringIO()

    def flush():
        if buf.tell() > 0:
            section = "\n".join(wrapper.wrap(buf.getvalue()))
            outfile.write(section + "\n")
            buf.truncate(0)

    for line in infile:
        if delimiter in line:
            flush()
            outfile.write(line.replace(delimiter, "\t"))
        elif not line.strip():
            flush()
            outfile.write("\n")
        else:
            buf.write(line)


def main():
    parser = argparse.ArgumentParser(description="Format a gophermap file.")
    parser.add_argument(
        'infile', nargs='?', type=argparse.FileType('r'), default=sys.stdin)
    parser.add_argument(
        '-o', '--outfile', nargs='?', type=argparse.FileType('w'),
        default=sys.stdout)
    parser.add_argument('-w', '--width', action='store', type=int, default=67)
    parser.add_argument('-d', '--delimiter', action='store', type=str, default="\t")
    args = parser.parse_args()
    process(args.infile, args.outfile, args.width, args.delimiter)

if __name__ == '__main__':
    main()