dmc/app/test/domain/wind_math_test.dart

import 'package:flutter_test/flutter_test.dart';

import 'package:dmc_app/domain/waypoint/flat_waypoint_list.dart';
import 'package:dmc_app/domain/wind/wind_math.dart';

void main() {
  group('interpolateAngle', () {
    test('nimmt den kuerzeren Weg ueber die 0/360-Grenze', () {
      expect(interpolateAngle(350, 10, 0.5), closeTo(0, 0.001));
    });

    test('interpoliert linear ohne Grenzuebergang', () {
      expect(interpolateAngle(10, 30, 0.5), closeTo(20, 0.001));
    });
  });

  group('interpolateWindAtHeight', () {
    const levels = [
      WindLevel(heightAmslM: 100, speedMs: 4, dirFromDeg: 200),
      WindLevel(heightAmslM: 300, speedMs: 8, dirFromDeg: 220),
    ];

    test('klemmt unterhalb des tiefsten Stuetzpunkts', () {
      final result = interpolateWindAtHeight(levels, 50);
      expect(result!.speedMs, 4);
      expect(result.dirFromDeg, 200);
    });

    test('klemmt oberhalb des hoechsten Stuetzpunkts', () {
      final result = interpolateWindAtHeight(levels, 500);
      expect(result!.speedMs, 8);
      expect(result.dirFromDeg, 220);
    });

    test('interpoliert linear zwischen zwei Stuetzpunkten', () {
      final result = interpolateWindAtHeight(levels, 200);
      expect(result!.speedMs, closeTo(6, 0.001));
      expect(result.dirFromDeg, closeTo(210, 0.001));
    });

    test('liefert null ohne Stuetzpunkte', () {
      expect(interpolateWindAtHeight(const [], 100), isNull);
    });
  });

  group('bearingBetweenDeg', () {
    test('nach Norden ergibt ~0 Grad', () {
      expect(bearingBetweenDeg(0, 0, 1, 0), closeTo(0, 0.5));
    });

    test('nach Osten ergibt ~90 Grad', () {
      expect(bearingBetweenDeg(0, 0, 0, 1), closeTo(90, 0.5));
    });
  });

  group('headTailwindComponent', () {
    test('Wind von hinten ergibt vollen positiven Rueckenwind', () {
      // Kurs 0 (Nord), Wind weht aus Sueden (180) - also von hinten.
      expect(headTailwindComponent(0, 10, 180), closeTo(10, 0.001));
    });

    test('Wind von vorne ergibt vollen negativen Gegenwind', () {
      // Kurs 0 (Nord), Wind weht aus Norden (0) - also von vorne.
      expect(headTailwindComponent(0, 10, 0), closeTo(-10, 0.001));
    });

    test('Seitenwind ergibt ~0 Laengskomponente', () {
      expect(headTailwindComponent(0, 10, 90), closeTo(0, 0.001));
    });
  });

  group('computeLegWindComponent / computeLegWind / computeGroundSpeeds', () {
    const a = Waypoint(
      lat: 0,
      lon: 0,
      altitudeM: 60,
      speedMs: 15,
      catchRadiusM: 60,
    );
    const bWithWind = Waypoint(
      lat: 1,
      lon: 0,
      altitudeM: 60,
      speedMs: 15,
      catchRadiusM: 60,
      windSpeedMs: 10,
      windDirFromDeg: 180,
    );
    const bWithoutWind = Waypoint(
      lat: 1,
      lon: 0,
      altitudeM: 60,
      speedMs: 15,
      catchRadiusM: 60,
    );

    test('null solange am Zielwegpunkt kein Wind geladen ist', () {
      expect(computeLegWindComponent(a, bWithoutWind), isNull);
    });

    test('Rueckenwind auf dem Leg erhoeht die Bodengeschwindigkeit', () {
      final component = computeLegWindComponent(a, bWithWind);
      expect(component, closeTo(10, 0.001));

      final groundSpeeds = computeGroundSpeeds([a, bWithWind]);
      expect(groundSpeeds.single, closeTo(25, 0.001));
    });

    test('computeLegWind liefert eine Komponente pro Leg', () {
      final legWind = computeLegWind([a, bWithWind, bWithoutWind]);
      expect(legWind, hasLength(2));
      expect(legWind[0], isNotNull);
      expect(legWind[1], isNull);
    });
  });
}