from mka.application.progress_timing import ProcessingTimer


class FakeClock:
    def __init__(self, value: float = 0.0) -> None:
        self.value = value

    def __call__(self) -> float:
        return self.value


def test_completed_duration_is_retained_while_active_stage_increases() -> None:
    clock = FakeClock(10.0)
    timer = ProcessingTimer(clock)
    timer.start_run()
    timer.start_stage("preparing")
    clock.value = 18.0
    timer.finish_stage("preparing")
    timer.start_stage("transcription")

    clock.value = 20.0
    first = timer.snapshot()
    clock.value = 25.5
    second = timer.snapshot()

    assert first.stage_durations == {"preparing": 8.0, "transcription": 2.0}
    assert second.stage_durations == {"preparing": 8.0, "transcription": 7.5}
    assert second.total_duration == 15.5


def test_failed_active_stage_and_total_duration_are_frozen() -> None:
    clock = FakeClock(2.0)
    timer = ProcessingTimer(clock)
    timer.start_run()
    clock.value = 5.0
    timer.start_stage("transcription")
    clock.value = 14.0
    timer.finish_run()
    clock.value = 99.0

    snapshot = timer.snapshot()

    assert snapshot.stage_durations["transcription"] == 9.0
    assert snapshot.total_duration == 12.0
    assert snapshot.running is False