#!/usr/bin/env python3
"""Создаёт и проверяет HDD-fixture группового F5."""

from __future__ import annotations

import pathlib
import sys


def payload(size: int, seed: int) -> bytes:
    return bytes(((index * 37 + seed) & 0xFF) for index in range(size))


def create(root: pathlib.Path) -> None:
    source = root / "GRSRC"
    target = root / "GRDST"
    source.mkdir(parents=True)
    target.mkdir()
    (source / "A.BIN").write_bytes(payload(10, 3))
    (source / "B.BIN").write_bytes(payload(4097, 11))
    (source / "C.BIN").write_bytes(b"")
    directory = source / "ADIR"
    directory.mkdir()
    (directory / "INSIDE.TXT").write_bytes(b"must not be copied\r\n")


def verify(root: pathlib.Path) -> None:
    source = root / "GRSRC"
    target = root / "GRDST"
    failures: list[str] = []
    expected = {
        "A.BIN": payload(10, 3),
        "B.BIN": payload(4097, 11),
        "C.BIN": b"",
    }

    for name, content in expected.items():
        source_path = source / name
        target_path = target / name
        if not source_path.is_file() or source_path.read_bytes() != content:
            failures.append(f"source изменён: {name}")
        if not target_path.is_file() or target_path.read_bytes() != content:
            failures.append(f"target не совпадает: {name}")
    target_inside = target / "ADIR" / "INSIDE.TXT"
    if (not target_inside.is_file() or
            target_inside.read_bytes() != b"must not be copied\r\n"):
        failures.append("выбранный каталог не скопирован рекурсивно")
    temporary = [path.name for path in target.rglob("*")
                 if path.name.upper().endswith(".TMP")]
    if temporary:
        failures.append(f"остались temp: {temporary}")
    inside = source / "ADIR" / "INSIDE.TXT"
    if not inside.is_file() or inside.read_bytes() != b"must not be copied\r\n":
        failures.append("исходный выбранный каталог изменён")

    if failures:
        for failure in failures:
            print(f"FAIL: {failure}")
        raise SystemExit(1)
    print("PASS: 3 selected files and selected directory copied; no temp.")


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()