import 'package:dmc_app/domain/mission/mission_stats.dart';
import 'package:dmc_app/domain/waypoint/flat_waypoint_list.dart';
import 'package:flutter_test/flutter_test.dart';

Waypoint _wp(double lat, double lon, {double speed = 15}) =>
    Waypoint(lat: lat, lon: lon, altitudeM: 60, speedMs: speed, catchRadiusM: 60);

void main() {
  group('computeMissionStats', () {
    test('leere/einzelne Wegpunktliste ergibt Distanz/Dauer 0', () {
      expect(computeMissionStats(const []).distanceM, 0);
      expect(computeMissionStats([_wp(0, 0)]).distanceM, 0);
      expect(computeMissionStats([_wp(0, 0)]).durationSec, 0);
    });

    test('zwei Wegpunkte: Distanz aus Grosskreis, Dauer aus Zielgeschwindigkeit', () {
      final stats = computeMissionStats([_wp(0, 0), _wp(0, 0.01, speed: 20)]);

      // 0.01 Grad Laengendifferenz am Aequator entspricht rund 1112 m.
      expect(stats.distanceM, closeTo(1112.6, 1));
      expect(stats.durationSec, closeTo(stats.distanceM / 20, 0.01));
    });

    test('mehrere Beine summieren sich, Dauer je Bein mit dessen Zielgeschwindigkeit', () {
      final stats = computeMissionStats(
        [_wp(0, 0, speed: 10), _wp(0, 0.01, speed: 20), _wp(0, 0.02, speed: 10)],
      );

      final leg1 = 1112.6;
      final leg2 = 1112.6;
      expect(stats.distanceM, closeTo(leg1 + leg2, 2));
      // Erstes Bein zaehlt mit der Geschwindigkeit des Zielwegpunkts (20),
      // zweites Bein mit dessen Zielwegpunkt (10).
      expect(stats.durationSec, closeTo(leg1 / 20 + leg2 / 10, 0.1));
    });
  });

  group('computeFlyMissionStatus', () {
    final waypoints = [_wp(0, 0), _wp(0, 0.01), _wp(0, 0.02)];

    test('kein aktiver Wegpunkt (null) ergibt null', () {
      expect(
        computeFlyMissionStatus(waypoints: waypoints, activeWaypointIndex: null),
        isNull,
      );
    });

    test('activeWaypointIndex ausserhalb der Liste ergibt null', () {
      expect(
        computeFlyMissionStatus(waypoints: waypoints, activeWaypointIndex: 3),
        isNull,
      );
      expect(
        computeFlyMissionStatus(waypoints: waypoints, activeWaypointIndex: -1),
        isNull,
      );
    });

    test('activeWaypointNumber ist 1-basiert (Index 1 -> Nummer 2)', () {
      final status = computeFlyMissionStatus(
        waypoints: waypoints,
        activeWaypointIndex: 1,
      );
      expect(status!.activeWaypointNumber, 2);
      expect(status.waypointCount, 3);
    });

    test('ohne Position (kein Fix) bleiben Distanz/ETA null', () {
      final status = computeFlyMissionStatus(
        waypoints: waypoints,
        activeWaypointIndex: 1,
      );
      expect(status!.distanceToActiveWaypointM, isNull);
      expect(status.etaToActiveWaypointSec, isNull);
    });

    test('mit Position wird die Distanz zum aktiven Wegpunkt berechnet', () {
      final status = computeFlyMissionStatus(
        waypoints: waypoints,
        activeWaypointIndex: 1,
        currentLat: 0,
        currentLon: 0,
      );
      // Wegpunkt 1 (Index 1) liegt bei (0, 0.01) - rund 1112.6 m vom
      // Ursprung entfernt.
      expect(status!.distanceToActiveWaypointM, closeTo(1112.6, 1));
      // Ohne Geschwindigkeit keine ETA.
      expect(status.etaToActiveWaypointSec, isNull);
    });

    test('mit Position und Geschwindigkeit wird die ETA berechnet', () {
      final status = computeFlyMissionStatus(
        waypoints: waypoints,
        activeWaypointIndex: 1,
        currentLat: 0,
        currentLon: 0,
        currentSpeedMs: 10,
      );
      expect(status!.etaToActiveWaypointSec, closeTo(1112.6 / 10, 0.1));
    });

    test('unter 0.5 m/s wird keine (irrefuehrende) ETA berechnet', () {
      final status = computeFlyMissionStatus(
        waypoints: waypoints,
        activeWaypointIndex: 1,
        currentLat: 0,
        currentLon: 0,
        currentSpeedMs: 0.1,
      );
      expect(status!.etaToActiveWaypointSec, isNull);
    });
  });
}