dmc/app/lib/transport/mock/mock_flight_controller_link.dart

import 'dart:async';

import '../../domain/waypoint/flat_waypoint_list.dart';
import '../flight_controller_link.dart';

/// Synthetische Telemetrie fuer UI-Entwicklung/Tests ohne Hardware oder SITL
/// (Architektur-Doku 3.1).
class MockFlightControllerLink implements FlightControllerLink {
  bool _armed = false;
  int? _activeWaypointIndex;
  StreamController<TelemetryFrame>? _telemetryController;
  Timer? _ticker;

  @override
  FcCapabilities get capabilities => const FcCapabilities(
        supportsMultiMission: true,
        supportsInFlightUpload: false,
        maxWaypoints: 60,
      );

  @override
  Future<void> connect() async {
    _telemetryController = StreamController<TelemetryFrame>.broadcast();
    _ticker = Timer.periodic(const Duration(seconds: 1), (_) {
      _telemetryController?.add(TelemetryFrame(
        lat: 52.5,
        lon: 13.4,
        altitudeM: 120,
        speedMs: 18,
        armed: _armed,
        activeWaypointIndex: _activeWaypointIndex,
      ));
    });
  }

  @override
  Future<void> disconnect() async {
    _ticker?.cancel();
    await _telemetryController?.close();
    _telemetryController = null;
  }

  @override
  Future<void> uploadMission(FlatWaypointList mission) async {
    // iNAV/MAVLink erlauben Mission-Upload nur im unarmed-Zustand (Doku 4.5).
    if (_armed) {
      throw StateError('Mission-Upload verweigert: Drohne ist armed.');
    }
    _activeWaypointIndex = mission.waypoints.isEmpty ? null : 0;
  }

  @override
  Future<void> setFlightMode(FlightMode mode) async {}

  @override
  Future<void> arm() async {
    _armed = true;
  }

  @override
  Stream<TelemetryFrame> subscribeTelemetry() {
    final controller = _telemetryController;
    if (controller == null) {
      throw StateError('subscribeTelemetry() vor connect() aufgerufen.');
    }
    return controller.stream;
  }

  @override
  Future<int?> readActiveWaypointIndex() async => _activeWaypointIndex;
}