from types import SimpleNamespace

from performance_reporter import PerformanceReporter


class _Pid:
    kp = 1.0
    ki = 0.1
    kd = 0.0


def _result(timestamp, flow, pressure_before, pressure_after, target=100.0):
    return SimpleNamespace(
        status="OK",
        timestamp=timestamp,
        measured_flow_slm=flow,
        target_flow_slm=target,
        pressure_before_kpa=pressure_before,
        pressure_kpa=pressure_after,
    )


def _reporter():
    return PerformanceReporter(
        _Pid(),
        window_s=0.2,
        sample_period_s=0.1,
        band_pct=1.0,
        pressure_band_kpa=1.0,
        flow_range_min_slm=0.0,
        flow_range_max_slm=300.0,
    )


def test_steady_uses_pressure_band_instead_of_flow_std():
    reporter = _reporter()
    # 流量标准差很大，但窗口均值为目标值；压力均在各自均值 ±1 kPa 内。
    reporter.observe(_result(0.0, 50.0, 200.0, 100.0))
    reporter.observe(_result(0.1, 150.0, 201.0, 99.0))

    assert reporter.steady_reached
    assert reporter.steady_mean == 100.0
    assert reporter.steady_std == 50.0


def test_pressure_outside_mean_band_prevents_steady_state():
    reporter = _reporter()
    reporter.observe(_result(0.0, 100.0, 200.0, 100.0))
    reporter.observe(_result(0.1, 100.0, 203.0, 100.0))

    assert not reporter.steady_reached


def test_missing_pressure_sample_is_not_used_for_steady_state():
    reporter = _reporter()
    reporter.observe(_result(0.0, 100.0, None, 100.0))
    reporter.observe(_result(0.1, 100.0, 200.0, 100.0))

    assert not reporter.steady_reached