import pytest

from app.processing import retry_async


async def test_retry_uses_exponential_delay_and_returns_success() -> None:
    calls = 0
    delays: list[float] = []

    async def operation() -> str:
        nonlocal calls
        calls += 1
        if calls < 3:
            raise RuntimeError("temporary failure")
        return "processed"

    async def record_sleep(delay: float) -> None:
        delays.append(delay)

    result = await retry_async(
        operation,
        attempts=3,
        base_delay=1,
        sleep=record_sleep,
    )

    assert result == "processed"
    assert calls == 3
    assert delays == [1, 2]


async def test_retry_raises_last_error_after_three_attempts() -> None:
    calls = 0

    async def operation() -> None:
        nonlocal calls
        calls += 1
        raise RuntimeError(f"failure {calls}")

    async def no_sleep(_: float) -> None:
        pass

    with pytest.raises(RuntimeError, match="failure 3"):
        await retry_async(
            operation,
            attempts=3,
            base_delay=1,
            sleep=no_sleep,
        )

    assert calls == 3