from __future__ import annotations

from datetime import UTC, datetime, timedelta

import pytest
from backup_tool.scheduler import next_nominal


def test_misfire_window_is_deterministic_for_delivery() -> None:
    nominal = datetime.now(UTC) - timedelta(seconds=901)
    next_run = next_nominal("* * * * *", "UTC", nominal)

    assert next_run > nominal
    assert (datetime.now(UTC) - nominal).total_seconds() > 900


@pytest.mark.parametrize("cron", ["* * * * * *", "invalid"])
def test_delivery_rejects_invalid_cron_before_enqueue(cron: str) -> None:
    with pytest.raises(ValueError):
        next_nominal(cron, "UTC")