#!/usr/bin/python3
# SPDX-License-Identifier: AGPL-3.0-or-later
"""
Set time zones with timedatectl (requires root permission).
"""

import argparse
import subprocess
import sys


def parse_arguments():
    """Return parsed command line arguments as dictionary."""
    parser = argparse.ArgumentParser()
    parser.add_argument(
        'timezone', help='Time zone to set; see "timedatectl list-timezones".')
    return parser.parse_args()


def _set_timezone(arguments):
    """Set time zone with timedatectl."""
    try:
        command = ['timedatectl', 'set-timezone', arguments.timezone]
        subprocess.run(command, stdout=subprocess.DEVNULL, check=True)
    except subprocess.CalledProcessError as exception:
        print('Error setting timezone:', exception, file=sys.stderr)
        sys.exit(1)


def main():
    """Parse arguments and perform all duties."""
    arguments = parse_arguments()
    _set_timezone(arguments)


if __name__ == '__main__':
    main()