from math import isclose

import pytest

from app.core.antenna import AntennaPattern, gain
from app.core.diffraction import bullington_loss, knife_edge_loss, knife_edge_v
from app.core.fresnel import earth_bulge, fresnel_radius, wavelength
from app.core.propagation import fspl
from app.core.surface import SurfaceProfile, SurfaceSample
from app.core.vegetation import P833Coefficients, p833_attenuation


def test_fspl_reference_value() -> None:
    assert isclose(fspl(433, 12.45), 107.08, abs_tol=0.05)


def test_fresnel_radius_reference_value() -> None:
    lmbda = wavelength(433_000_000)
    assert isclose(fresnel_radius(lmbda, 6_225, 6_225), 46.45, abs_tol=0.05)


def test_earth_bulge_reference_value() -> None:
    assert isclose(earth_bulge(6_225, 6_225, 1.333), 2.28, abs_tol=0.02)


@pytest.mark.parametrize(
    ("v", "expected"),
    [
        (-0.79, 0.0),
        (0.0, 6.03),
        (1.0, 13.93),
    ],
)
def test_knife_edge_loss_reference_values(v: float, expected: float) -> None:
    assert isclose(knife_edge_loss(v), expected, abs_tol=0.05)


def test_bullington_loss_uses_dominant_equivalent_edge() -> None:
    profile = SurfaceProfile(
        distance_m=10_000,
        samples=[
            SurfaceSample(
                i=0,
                lat=0,
                lon=0,
                distance_m=0,
                ground_m=0,
                building_m=0,
                canopy_m=0,
                surface_m=0,
            ),
            SurfaceSample(
                i=1,
                lat=0,
                lon=0,
                distance_m=5_000,
                ground_m=20,
                building_m=0,
                canopy_m=0,
                surface_m=20,
            ),
            SurfaceSample(
                i=2,
                lat=0,
                lon=0,
                distance_m=10_000,
                ground_m=0,
                building_m=0,
                canopy_m=0,
                surface_m=0,
            ),
        ],
    )
    v = knife_edge_v(20, 5_000, 5_000, 433_000_000)

    assert isclose(bullington_loss(profile, 0, 0, 433_000_000), knife_edge_loss(v))


def test_bullington_loss_does_not_sum_every_dem_sample() -> None:
    samples = [
        SurfaceSample(
            i=i,
            lat=0,
            lon=0,
            distance_m=i * 100,
            ground_m=5 if 20 <= i <= 80 else 0,
            building_m=0,
            canopy_m=0,
            surface_m=5 if 20 <= i <= 80 else 0,
        )
        for i in range(101)
    ]
    profile = SurfaceProfile(distance_m=10_000, samples=samples)

    assert bullington_loss(profile, 0, 0, 433_000_000) < 30


def test_p833_formula_with_supplied_coefficients() -> None:
    attenuation = p833_attenuation(
        depth_m=100,
        freq_hz=433_000_000,
        forest_type="coniferous",
        coefficients=P833Coefficients(gamma_db_per_m=0.2, max_attenuation_db=30),
    )
    assert isclose(attenuation, 14.60, abs_tol=0.05)


def test_sector_antenna_gain_peaks_at_boresight() -> None:
    pattern = AntennaPattern(
        pattern="sector",
        azimuth_deg=90,
        gain_dbi=8,
        beamwidth_h=65,
        beamwidth_v=15,
    )
    assert gain(pattern, 90, 0) == 8
    assert gain(pattern, 270, 0) < 8