import math
from pathlib import Path
from types import SimpleNamespace

import pytest

from leonida.park import M_PER_DEG_LAT, M_PER_DEG_LON, REF_LAT, REF_LON, ParkFit, load_park, local_metres

DATA = Path(__file__).resolve().parents[1] / "data"


def latlon(x: float, y: float) -> tuple[float, float]:
    """Lokale Meter -> Breite/Länge, die Umkehrung von local_metres."""
    return REF_LAT + y / M_PER_DEG_LAT, REF_LON + x / M_PER_DEG_LON


# Echter Park 100 × 200 m, Spielpark 200 × 400 m ab (1000 | 1000), Anlage 50 m vom Westrand:
# Welt-x = 1050 + x, Welt-y = 1000 + 2 · y.
FAKE = SimpleNamespace(
    real={"sw": latlon(0, 0), "se": latlon(100, 0), "nw": latlon(0, 200)},
    game={"sw": (1000.0, 1000.0), "se": (1200.0, 1000.0), "ne": (1200.0, 1400.0), "nw": (1000.0, 1400.0)},
    scale_u=1.0, offset_u=50.0,
)


def test_reference_point_is_the_local_origin():
    assert math.dist(local_metres(REF_LAT, REF_LON), (0.0, 0.0)) < 1e-9


def test_park_coords_run_west_to_east_and_south_to_north():
    s, t = ParkFit(FAKE).park_coords(25.0, 150.0)
    assert (s, t) == pytest.approx((0.25, 0.75))


def test_real_corners_and_centre_land_in_the_game_park():
    fit = ParkFit(FAKE)
    assert fit.to_game(*latlon(0, 0)) == pytest.approx((1050.0, 1000.0))
    assert fit.to_game(*latlon(100, 0)) == pytest.approx((1150.0, 1000.0))
    assert fit.to_game(*latlon(0, 200)) == pytest.approx((1050.0, 1400.0))
    assert fit.to_game(*latlon(50, 100)) == pytest.approx((1100.0, 1200.0))


def test_quads_cover_real_and_game_park():
    fit = ParkFit(FAKE)
    assert fit.real_quad().area == pytest.approx(100 * 200)
    assert fit.game_quad.area == pytest.approx(200 * 400)


def test_committed_fit_puts_tribune_and_hood_yard_within_one_and_a_half_metres():
    config = load_park(DATA / "flamingo-park.toml")
    fit = ParkFit(config)
    for anchor in config.anchors:
        assert math.dist(fit.to_game(*anchor.real), anchor.game) <= 1.5, anchor.name


def test_committed_fit_keeps_the_south_edge_true_to_scale_and_offset_from_the_corner():
    config = load_park(DATA / "flamingo-park.toml")
    fit = ParkFit(config)
    sw, se, nw = (fit.to_game(*config.real[key]) for key in ("sw", "se", "nw"))
    assert math.dist(sw, se) == pytest.approx(fit.real_width, abs=0.01)
    assert fit.real_width == pytest.approx(200.57, abs=0.01)
    assert math.dist(sw, config.game["sw"]) == pytest.approx(config.offset_u, abs=0.01)
    assert math.dist(nw, config.game["nw"]) == pytest.approx(config.offset_u, abs=0.01)