#!/usr/bin/env python3.10

import argparse
import dataclasses
import datetime
import json
import logging
from pathlib import Path
import re


def parse_args():
    arger = argparse.ArgumentParser(formatter_class=argparse.ArgumentDefaultsHelpFormatter)
    arger.add_argument('dirs', help='Path to the directories', type=Path, nargs='+')
    return arger.parse_args()


def natural_sort_key(path: Path) -> tuple[str, ...]:
    s = path.stem
    return tuple(f'{int(p):010d}' if p.isnumeric() else p for p in re.findall(r'(\D+|\d+)', s))


def rename_children(cwd: Path) -> None:
    assert cwd.is_dir()

    files = [f for f in cwd.glob('*') if f.is_file()]
    files = sorted(files, key=natural_sort_key)

    new_stem = cwd.name

    jobs = []
    for i, f in enumerate(files):
        target = f.with_stem(f'{new_stem}__{i:04d}')
        if f.suffix == '.jpeg':
            target = target.with_suffix('.jpg')
        if target.is_file():
            logging.error(f'target already exists: {target}')
            continue
        jobs.append(MoveOp(source=f, target=target))
        f.rename(target)

    if not jobs:
        return

    write_undo_script(Path.cwd(), jobs)


@dataclasses.dataclass
class MoveOp:
    source: Path
    target: Path

    def to_dict(self) -> dict:
        return {
            'source': str(self.source),
            'target': str(self.target),
        }


def write_undo_script(save_dir: Path, ops: list[MoveOp]):
    now = datetime.datetime.now().isoformat().replace(':', '')
    save_path = save_dir / f'undo_{now}.json'
    with save_path.open('w', encoding='utf-8') as f:
        for it in ops:
            f.write(json.dumps(it.to_dict()) + '\n')


def main():
    args = parse_args()
    for d in args.dirs:
        rename_children(d)


if __name__ == '__main__':
    main()