import 'package:flutter_riverpod/flutter_riverpod.dart';
import '../data/routing_repository.dart';

class RoutingState {
  final double? originLat;
  final double? originLon;
  final String originName;
  final double? destLat;
  final double? destLon;
  final String destName;
  final String profile; // driving, walking, cycling
  final List<RouteData> routes;
  final int selectedRouteIndex;
  final bool isLoading;
  final String? error;

  const RoutingState({
    this.originLat,
    this.originLon,
    this.originName = 'My Location',
    this.destLat,
    this.destLon,
    this.destName = '',
    this.profile = 'driving',
    this.routes = const [],
    this.selectedRouteIndex = 0,
    this.isLoading = false,
    this.error,
  });

  RoutingState copyWith({
    double? originLat,
    double? originLon,
    String? originName,
    double? destLat,
    double? destLon,
    String? destName,
    String? profile,
    List<RouteData>? routes,
    int? selectedRouteIndex,
    bool? isLoading,
    String? error,
    bool clearError = false,
  }) {
    return RoutingState(
      originLat: originLat ?? this.originLat,
      originLon: originLon ?? this.originLon,
      originName: originName ?? this.originName,
      destLat: destLat ?? this.destLat,
      destLon: destLon ?? this.destLon,
      destName: destName ?? this.destName,
      profile: profile ?? this.profile,
      routes: routes ?? this.routes,
      selectedRouteIndex: selectedRouteIndex ?? this.selectedRouteIndex,
      isLoading: isLoading ?? this.isLoading,
      error: clearError ? null : (error ?? this.error),
    );
  }

  RouteData? get selectedRoute =>
      routes.isNotEmpty && selectedRouteIndex < routes.length
          ? routes[selectedRouteIndex]
          : null;
}

class RoutingNotifier extends StateNotifier<RoutingState> {
  final RoutingRepository _repository;

  RoutingNotifier(this._repository) : super(const RoutingState());

  void setOrigin(double lat, double lon, String name) {
    state = state.copyWith(
      originLat: lat,
      originLon: lon,
      originName: name,
      routes: [],
    );
  }

  void setDestination(double lat, double lon, String name) {
    state = state.copyWith(
      destLat: lat,
      destLon: lon,
      destName: name,
      routes: [],
    );
  }

  void setProfile(String profile) {
    state = state.copyWith(profile: profile, routes: []);
  }

  void selectRoute(int index) {
    state = state.copyWith(selectedRouteIndex: index);
  }

  Future<void> calculateRoute() async {
    if (state.originLat == null ||
        state.originLon == null ||
        state.destLat == null ||
        state.destLon == null) {
      state = state.copyWith(error: 'Please set both origin and destination.');
      return;
    }

    state = state.copyWith(isLoading: true, clearError: true, routes: []);

    try {
      final routes = await _repository.getRoute(
        profile: state.profile,
        originLat: state.originLat!,
        originLon: state.originLon!,
        destLat: state.destLat!,
        destLon: state.destLon!,
      );
      if (mounted) {
        state = state.copyWith(
          routes: routes,
          selectedRouteIndex: 0,
          isLoading: false,
        );
      }
    } catch (e) {
      if (mounted) {
        state = state.copyWith(
          isLoading: false,
          error: 'Could not calculate route. Please try again.',
        );
      }
    }
  }
}

final routingProvider =
    StateNotifierProvider.autoDispose<RoutingNotifier, RoutingState>((ref) {
  return RoutingNotifier(ref.watch(routingRepositoryProvider));
});