nethack_backup.py

#!/usr/bin/env python
"""
Usage: %(scriptName)s --help -> get help

Make a backup of the nethack save file (this is cheating!) 
or choose one of the already backed up savegames to restore.

Nethack must not be running while using this script!

Happy slaying,
Sven Hergenhahn https://github.com/svenXY
"""

import argparse
import os
import sys
import shutil
from pathlib import Path
from datetime import datetime

# set your paths here - 
# SAVEDIR will be created if it does not yet exist
NH_PLAYGROUND = Path("/usr/local/share/nethack/save")
SAVEDIR = Path("~/nethack/savegames").expanduser()


def parse_args():
    parser = argparse.ArgumentParser(description='Backup or restore a nethack savegame')
    group = parser.add_mutually_exclusive_group()
    group.add_argument('--backup', '-b', dest='action',
                        help='backup a save game (=default)', action='store_const', const='backup', default='backup')
    group.add_argument('--restore', '-r', dest='action',
                        help='restore a saved game', action='store_const', const='restore')
    parser.add_argument('message', nargs='*', default=[])

    return parser.parse_args()


def make_menu(files):
    for idx, val in enumerate(files):
        print(f'{idx:<3} {val.name}')

    print()
    try:
        idx = input('\n'.join(['Gib eine Nummer ein, ',
                               '<return> für die neueste Datei',
                               'oder <ctrl-c> um abzubrechen: ']))
    except KeyboardInterrupt:
        print('\nNever mind.')
        sys.exit()
    if idx:
        return files[int(idx)]
    return files[-1]


def restore_file(rest_file):
    if rest_file.is_file():
        dest_name = rest_file.name.split('_')[1]
        dest_path = Path(os.path.join(NH_PLAYGROUND, dest_name))
        try:
            shutil.copy(rest_file, dest_path)
            shutil.chown(dest_path, group='admin')
            os.chmod(dest_path, 0o660)
            print(f'{rest_file} has been restored')
        except OSError as e_msg:
            print(f'Failed to restore {rest_file}: {e_msg}')
    else:
        print(f'Not a file: {rest_file}. Exit')


def backup_file(message):
    os.makedirs(SAVEDIR, exist_ok=True)
    save_game = sorted(NH_PLAYGROUND.glob('*.Z'), key=os.path.getmtime)[-1]
    if save_game.is_file():
        date_format = datetime.now().strftime('%Y-%m-%d-%H-%M')
        if message:
            msg = '_'.join(message)
        else:
            msg = 'nomsg'
        bck_file = '_'.join([date_format, msg, save_game.name])
        try:
            shutil.copy(save_game, os.path.join(SAVEDIR, bck_file))
            print(f'{bck_file} has been backed up')
        except OSError as e_msg:
            print(f'Failed to backup {bck_file}: {e_msg}')
    else:
        print(f'Not a file: {save_game}. Exit')


if __name__ == "__main__":
    args = parse_args()
    if args.action == 'backup':
        backup_file(args.message)
    elif args.action == 'restore':
        all_backups = sorted(SAVEDIR.glob('*.Z'), key=os.path.getmtime)
        my_restore = make_menu(all_backups)
        restore_file(my_restore)