from math import isclose

from app.core.surface import SurfaceProfile, SurfaceSample
from app.models.coverage import LinkRx, LinkTx
from app.models.link import LinkBudgetRequest
from app.services import link as link_service


def test_link_budget_includes_vegetation_loss(monkeypatch) -> None:
    monkeypatch.setattr(link_service, "vegetation_loss_along", lambda *args, **kwargs: 5.0)
    monkeypatch.setattr(
        link_service,
        "surface_profile_from_points",
        lambda points, *args, **kwargs: SurfaceProfile(
            distance_m=points[-1].distance_m,
            samples=[
                SurfaceSample(
                    i=index,
                    lat=point.lat,
                    lon=point.lon,
                    distance_m=point.distance_m,
                    ground_m=0,
                    building_m=0,
                    canopy_m=0,
                    surface_m=0,
                )
                for index, point in enumerate(points)
            ],
        ),
    )
    request = LinkBudgetRequest(
        tx=LinkTx(lat=60.17, lon=24.94, height_agl=30, power_dbm=37, gain_dbi=8),
        rx=LinkRx(
            lat=60.25,
            lon=25.10,
            height_agl=2,
            gain_dbi=2,
            sensitivity_dbm=-110,
        ),
        frequency_mhz=433,
        model="manual",
        include_vegetation=True,
    )

    result = link_service.link_budget(request)

    assert result.vegetation_db == 5.0
    assert result.los_clear is result.fresnel_clear
    assert result.fresnel_violations_count >= 0
    assert isclose(
        result.total_loss_db,
        result.fspl_db + result.diffraction_db + result.vegetation_db + result.atmospheric_db,
    )


def test_link_budget_includes_diffraction_loss(monkeypatch) -> None:
    monkeypatch.setattr(link_service, "vegetation_loss_along", lambda *args, **kwargs: 0.0)

    def fake_profile(points, *args, **kwargs):
        midpoint = len(points) // 2
        samples = []
        for index, point in enumerate(points):
            obstacle = 20.0 if index == midpoint else 0.0
            samples.append(
                SurfaceSample(
                    i=index,
                    lat=point.lat,
                    lon=point.lon,
                    distance_m=point.distance_m,
                    ground_m=obstacle,
                    building_m=0,
                    canopy_m=0,
                    surface_m=obstacle,
                )
            )
        return SurfaceProfile(distance_m=points[-1].distance_m, samples=samples)

    monkeypatch.setattr(link_service, "surface_profile_from_points", fake_profile)
    request = LinkBudgetRequest(
        tx=LinkTx(lat=60.17, lon=24.94, height_agl=0, power_dbm=37, gain_dbi=8),
        rx=LinkRx(
            lat=60.25,
            lon=25.10,
            height_agl=0,
            gain_dbi=2,
            sensitivity_dbm=-110,
        ),
        frequency_mhz=433,
        model="manual",
        include_buildings=False,
        include_vegetation=False,
    )

    result = link_service.link_budget(request)

    assert result.diffraction_db > 0
    assert isclose(
        result.total_loss_db,
        result.fspl_db + result.diffraction_db + result.atmospheric_db,
    )
    assert result.fresnel_clear is False
    assert result.los_clear is False
    assert result.fresnel_quality == "blocked"
    assert result.geometric_los is False
    assert result.fresnel_violations_count > 0
    assert result.geometric_obstructions_count > 0
    assert result.worst_obstruction is not None


def test_link_viable_depends_on_margin_not_fresnel_quality(monkeypatch) -> None:
    monkeypatch.setattr(link_service, "vegetation_loss_along", lambda *args, **kwargs: 0.0)

    def fake_profile(points, *args, **kwargs):
        midpoint = len(points) // 2
        return SurfaceProfile(
            distance_m=points[-1].distance_m,
            samples=[
                SurfaceSample(
                    i=index,
                    lat=point.lat,
                    lon=point.lon,
                    distance_m=point.distance_m,
                    ground_m=20.0 if index == midpoint else 0.0,
                    building_m=0,
                    canopy_m=0,
                    surface_m=20.0 if index == midpoint else 0.0,
                )
                for index, point in enumerate(points)
            ],
        )

    monkeypatch.setattr(link_service, "surface_profile_from_points", fake_profile)
    request = LinkBudgetRequest(
        tx=LinkTx(lat=60.17, lon=24.94, height_agl=0, power_dbm=70, gain_dbi=8),
        rx=LinkRx(
            lat=60.25,
            lon=25.10,
            height_agl=0,
            gain_dbi=2,
            sensitivity_dbm=-120,
        ),
        frequency_mhz=433,
        model="manual",
        include_buildings=False,
        include_vegetation=False,
    )

    result = link_service.link_budget(request)

    assert result.fade_margin_db > 0
    assert result.fresnel_quality == "blocked"
    assert result.fresnel_clear is False
    assert result.link_viable is True