from pyproj import Geod

from app.core.antenna import AntennaPattern, gain
from app.models.antenna import (
    AntennaPatternSpec,
    BeamRequest,
    BeamResponse,
    PatternResponse,
    PatternSample,
)

_GEOD = Geod(ellps="WGS84")


def _to_core(spec: AntennaPatternSpec) -> AntennaPattern:
    return AntennaPattern(
        pattern=spec.pattern,
        azimuth_deg=spec.azimuth_deg,
        tilt_deg=spec.tilt_deg,
        gain_dbi=spec.gain_dbi,
        beamwidth_h=spec.beamwidth_h,
        beamwidth_v=spec.beamwidth_v,
        front_to_back_db=spec.front_to_back_db,
        sidelobe_floor_db=spec.sidelobe_floor_db,
    )


def normalize_pattern(spec: AntennaPatternSpec) -> PatternResponse:
    pattern = _to_core(spec)
    samples = [
        PatternSample(azimuth_deg=az, elevation_deg=0, gain_dbi=gain(pattern, az, 0))
        for az in range(0, 360, 5)
    ]
    return PatternResponse(pattern=spec.pattern, samples=samples)


def beam_geometry(request: BeamRequest) -> BeamResponse:
    antenna = request.antenna
    half_width = (antenna.beamwidth_h or 360.0) / 2.0
    if antenna.pattern == "omni":
        azimuths = list(range(0, 361, 10))
    else:
        start = antenna.azimuth_deg - half_width
        end = antenna.azimuth_deg + half_width
        azimuths = [start + (end - start) * i / 32 for i in range(33)]

    coords = [[request.origin.lon, request.origin.lat]]
    for azimuth in azimuths:
        lon, lat, _ = _GEOD.fwd(request.origin.lon, request.origin.lat, azimuth, request.radius_m)
        coords.append([lon, lat])
    coords.append([request.origin.lon, request.origin.lat])

    return BeamResponse(
        geojson={
            "type": "Feature",
            "properties": {
                "pattern": antenna.pattern,
                "azimuth_deg": antenna.azimuth_deg,
                "radius_m": request.radius_m,
            },
            "geometry": {"type": "Polygon", "coordinates": [coords]},
        }
    )