#!/usr/bin/env python3
"""This script wraps the usermod command to allow user account renames via
sudoers."""
import os
import sys
import subprocess


def rename_user(old_username, new_username):
    """Given an old and a new username, renames user on disk with usermod.
    Raises if the usermod call fails."""

    args = [
        'pkill',
        '-u',
        old_username]
    subprocess.run(args, check=False)

    # Rename user
    args = [
        'usermod',
        '-l',
        new_username,
        '-m',
        '-d',
        os.path.join('/home', new_username),
        old_username
    ]
    subprocess.run(args, check=True)

    # Rename their group
    args = [
        'groupmod',
        '-n',
        new_username,
        old_username
    ]
    subprocess.run(args, check=True)


def main(argv):
    if len(argv) < 3:
        print('[rename_user] Too few arguments passed.', file=sys.stderr)
        return 1

    try:
        rename_user(argv[1], argv[2])
    except subprocess.CalledProcessError as e:
        print('[rename_user] {}'.format(e), file=sys.stderr)
        return 2

    return 0


if __name__ == '__main__':
    exit(main(sys.argv))