from datetime import datetime, timedelta, timezone

from app.services.oee import calculate_oee_metrics


def test_calculate_oee_metrics() -> None:
    metrics = calculate_oee_metrics(
        planned_time_sec=3600,
        downtime_sec=600,
        total_cycles=100,
        performance_time_sec=2500,
        theoretical_cycle_time_sec=25,
        total_produced_qty=200,
        scrap_qty=10,
    )

    assert round(metrics.availability, 4) == 0.8333
    assert round(metrics.performance, 4) == 0.8333
    assert round(metrics.quality, 4) == 0.95
    assert round(metrics.oee, 4) == 0.6597


def test_future_window_uses_current_time_bound(monkeypatch) -> None:
    from app.services import oee

    fixed_now = datetime(2026, 6, 14, 12, 0, tzinfo=timezone.utc)

    class FixedDateTime(datetime):
        @classmethod
        def now(cls, tz=None):
            return fixed_now if tz else fixed_now.replace(tzinfo=None)

    monkeypatch.setattr(oee, "datetime", FixedDateTime)

    start = datetime(2026, 6, 14, 0, 0, tzinfo=timezone.utc)
    end = datetime(2026, 6, 15, 0, 0, tzinfo=timezone.utc)

    assert oee.overlap_seconds(start, fixed_now, start, end) == timedelta(hours=12).total_seconds()