#!/usr/bin/env python3
"""Создаёт и проверяет runtime-cancel рекурсивного группового F8."""

from __future__ import annotations

import pathlib
import sys


DIRECTORY_COUNT = 180


def payload(index: int) -> bytes:
    return bytes(((offset * 17 + index) & 0xFF) for offset in range(97))


def create(root: pathlib.Path) -> None:
    panel = root / "CDEL"
    tree = panel / "TREE"
    tree.mkdir(parents=True)

    for index in range(DIRECTORY_COUNT):
        child = tree / f"D{index:03d}"
        child.mkdir()
        (child / "ITEM.BIN").write_bytes(payload(index))

    (panel / "TOP.BIN").write_bytes(b"top-level selected file\r\n")
    (panel / "KEEP.TXT").write_bytes(b"unselected cancel sentinel\r\n")


def verify(root: pathlib.Path) -> None:
    panel = root / "CDEL"
    failures: list[str] = []

    if (panel / "TOP.BIN").exists():
        failures.append("завершённое удаление TOP.BIN ошибочно откатилось")

    keep = panel / "KEEP.TXT"
    if not keep.is_file() or keep.read_bytes() != b"unselected cancel sentinel\r\n":
        failures.append("невыбранный KEEP.TXT отсутствует или изменён")

    tree = panel / "TREE"
    if not tree.is_dir():
        failures.append("TREE успел удалиться целиком: runtime-cancel не подтверждён")
    else:
        remaining = list(tree.glob("D*/ITEM.BIN"))
        if not remaining:
            failures.append("после cancel не осталось ни одного файла дерева")
        for path in remaining:
            index = int(path.parent.name[1:])
            if path.read_bytes() != payload(index):
                failures.append(f"повреждён оставшийся файл: {path.name}")
                break

    if failures:
        for failure in failures:
            print(f"FAIL: {failure}")
        raise SystemExit(1)
    print("PASS: runtime cancel kept remaining tree; completed TOP delete remains.")


def main() -> None:
    if len(sys.argv) != 3 or sys.argv[1] not in {"create", "verify"}:
        raise SystemExit(f"usage: {sys.argv[0]} create|verify DIR")
    root = pathlib.Path(sys.argv[2])
    if sys.argv[1] == "create":
        create(root)
    else:
        verify(root)


if __name__ == "__main__":
    main()