"""S1-T07: Wind simulation unit tests."""

import numpy as np

from remodel_engine.generation.wind import annual_plf, simulate_wind
from remodel_engine.schemas.generation import WindConfig

SMALL_WIND = WindConfig(
    location_id="RJ",
    capacity_mw=100.0,
)


def test_output_shape() -> None:
    df = simulate_wind(SMALL_WIND)
    assert df.shape == (25 * 8760, 6)
    assert set(df.columns) == {
        "year", "hour", "wind_speed_hub", "power_fraction", "ac_power_mw", "degradation_factor"
    }


def test_plf_in_reasonable_range() -> None:
    """Rajasthan wind PLF should be 25 %-45 %."""
    df = simulate_wind(SMALL_WIND)
    plf = annual_plf(df, SMALL_WIND.capacity_mw)
    assert all(0.25 <= v <= 0.45 for v in plf), f"PLF out of range: {plf.values}"


def test_no_negative_power() -> None:
    df = simulate_wind(SMALL_WIND)
    assert (df["ac_power_mw"] >= 0).all()


def test_power_never_exceeds_capacity() -> None:
    df = simulate_wind(SMALL_WIND)
    assert (df["ac_power_mw"] <= SMALL_WIND.capacity_mw + 1e-9).all()


def test_power_fraction_in_01() -> None:
    df = simulate_wind(SMALL_WIND)
    assert (df["power_fraction"] >= 0).all()
    assert (df["power_fraction"] <= 1.0 + 1e-9).all()


def test_degradation_monotonically_decreasing() -> None:
    df = simulate_wind(SMALL_WIND)
    yearly_deg = df.groupby("year")["degradation_factor"].first().values
    diffs = np.diff(yearly_deg)
    assert (diffs < 0).all(), "Wind degradation factors must decrease each year"


def test_year1_degradation_is_one() -> None:
    """Wind degradation starts at 1.0 in year 1 (no LID, unlike solar)."""
    df = simulate_wind(SMALL_WIND)
    y1_deg = df[df["year"] == 1]["degradation_factor"].iloc[0]
    assert abs(y1_deg - 1.0) < 1e-9


def test_zero_wind_speed_gives_zero_power() -> None:
    """Hours with zero wind (below cut-in) must produce zero power."""
    df = simulate_wind(SMALL_WIND)
    zero_wind = df[df["wind_speed_hub"] < 3.0]
    if len(zero_wind) > 0:
        assert (zero_wind["power_fraction"] < 1e-9).all()


def test_gale_wind_cutout() -> None:
    """Wind speeds above cut-out (25 m/s) should produce zero power."""
    df = simulate_wind(SMALL_WIND)
    gale = df[df["wind_speed_hub"] > 25.0]
    if len(gale) > 0:
        assert (gale["ac_power_mw"] < 1e-9).all()


def test_shear_increases_wind_speed() -> None:
    """Hub height > ref height → hub wind speed > ref wind speed."""
    cfg = WindConfig(
        location_id="RJ",
        capacity_mw=100.0,
        hub_height_m=140.0,
        ref_height_m=100.0,
        wind_shear_exponent=0.14,
    )
    df = simulate_wind(cfg)
    # hub speeds should be larger than reference speeds on average
    from remodel_engine.catalog.loader import load_wind_profile
    ref_speeds = load_wind_profile("RJ")
    hub_speeds = df[df["year"] == 1]["wind_speed_hub"].values
    assert hub_speeds.mean() > ref_speeds.mean()


def test_ka_plf_reasonable() -> None:
    cfg = WindConfig(location_id="KA", capacity_mw=100.0)
    df = simulate_wind(cfg)
    plf = annual_plf(df, cfg.capacity_mw)
    assert all(0.30 <= v <= 0.55 for v in plf)