import 'dart:convert';
import 'dart:io';
import 'dart:typed_data';
import 'package:flutter/material.dart';
import 'package:flutter_dotenv/flutter_dotenv.dart';
import 'package:flutter/services.dart';
import 'package:http/http.dart' as http;
import 'package:mapbox_maps_flutter/mapbox_maps_flutter.dart' as mapbox;
import 'package:shared_preferences/shared_preferences.dart';
import 'package:geolocator/geolocator.dart' as geo;

import '../classes/alert.dart';
import '../variable/globals.dart' as globals;
import '../classes/MyDrawer.dart';
import '../classes/auth_service.dart';

import 'package:flutter_localizations/flutter_localizations.dart';
import 'package:covas_mobile/gen_l10n/app_localizations.dart';
import 'package:provider/provider.dart';
import '../locale_provider.dart';

void main() async {
  WidgetsFlutterBinding.ensureInitialized();
  await dotenv.load(fileName: ".env");

  // Set the access token globally
  mapbox.MapboxOptions.setAccessToken(dotenv.env['MAPBOX_ACCESS_TOKEN'] ?? '');

  runApp(const MyApp());
}

class MyApp extends StatelessWidget {
  const MyApp({Key? key}) : super(key: key);

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Flutter Directions Example',
      theme: ThemeData(primarySwatch: Colors.blue),
      home: const MapboxPages(title: 'Event Location', place: "Flutter"),
    );
  }
}

class MapboxPages extends StatefulWidget {
  const MapboxPages({Key? key, required this.title, required this.place})
      : super(key: key);

  final String title;
  final String place;

  @override
  State<MapboxPages> createState() => _MapboxPagesState();
}

class _MapboxPagesState extends State<MapboxPages> with ShowAlertDialog {
  final AuthService _authService = AuthService();

  mapbox.MapboxMap? mapboxMap;
  mapbox.PointAnnotationManager? pointAnnotationManager;
  mapbox.PolylineAnnotationManager? polylineAnnotationManager;

  double longitude = 0.0;
  double latitude = 0.0;
  bool isLoading = true;
  mapbox.Point? userPosition;
  bool isUserPositionInitialized = false;

  String selectedMode = 'driving';
  List<List<double>> routeCoordinates = [];

  @override
  void initState() {
    super.initState();
    _authService.checkTokenStatus(context);
    _getUserLocation();
  }

  Future<void> _getEventInfo() async {
    SharedPreferences prefs = await SharedPreferences.getInstance();
    var accessToken = prefs.getString("access_token") ?? "";

    if (accessToken.isNotEmpty) {
      var urlGet = Uri.parse("${globals.api}/events/${widget.title}");

      var responseGet = await http.get(urlGet,
          headers: {HttpHeaders.cookieHeader: 'access_token=${accessToken}'});
      if (responseGet.statusCode == 200) {
        var events = jsonDecode(utf8.decode(responseGet.bodyBytes));
        latitude = events["latitude"];
        longitude = events["longitude"];

        setState(() => isLoading = false);
      } else {
        _handleErrorResponse(responseGet.statusCode);
      }
    } else {
      showAlertDialog(context, "Error", "Invalid cache.");
    }
  }

  void _handleErrorResponse(int statusCode) {
    final errorMessage = "Error $statusCode fetching event";
    showAlertDialog(context, "Error", errorMessage);
  }

  Future<void> _getUserLocation() async {
    try {
      bool serviceEnabled = await geo.Geolocator.isLocationServiceEnabled();
      if (!serviceEnabled) return;

      geo.LocationPermission permission =
          await geo.Geolocator.checkPermission();
      if (permission == geo.LocationPermission.denied) {
        permission = await geo.Geolocator.requestPermission();
      }

      if (permission == geo.LocationPermission.deniedForever) return;

      geo.Position position = await geo.Geolocator.getCurrentPosition();
      setState(() {
        userPosition = mapbox.Point(
            coordinates:
                mapbox.Position(position.latitude, position.longitude));
        isUserPositionInitialized = true;
      });

      _getEventInfo();
    } catch (e) {
      showAlertDialog(context, "Error", "Failed to get location");
    }
  }

  Future<void> _fetchRoute(
      mapbox.Point origin, mapbox.Point destination, String mode) async {
    final url = Uri.parse(
      'https://api.mapbox.com/directions/v5/mapbox/$mode/${origin.coordinates.lng},${origin.coordinates.lat};${destination.coordinates.lng},${destination.coordinates.lat}?geometries=geojson&access_token=${dotenv.env['MAPBOX_ACCESS_TOKEN']}',
    );

    final response = await http.get(url);
    if (response.statusCode == 200) {
      final data = jsonDecode(response.body);
      final geometry = data['routes'][0]['geometry']['coordinates'];
      setState(() {
        routeCoordinates = (geometry as List)
            .map<List<double>>((coord) => [coord[0], coord[1]])
            .toList();
      });
    }
  }

  Future<void> _drawRouteAndMarkers() async {
    if (mapboxMap == null || !isUserPositionInitialized) return;

    // Managers
    pointAnnotationManager ??=
        await mapboxMap!.annotations.createPointAnnotationManager();
    polylineAnnotationManager ??=
        await mapboxMap!.annotations.createPolylineAnnotationManager();

    // Clear old annotations
    await pointAnnotationManager!.deleteAll();
    await polylineAnnotationManager!.deleteAll();

    final destination =
        mapbox.Point(coordinates: mapbox.Position(longitude, latitude));

    // Add user marker
    final userIcon = await _loadMarkerImage('images/marker.png');
    await pointAnnotationManager!.create(mapbox.PointAnnotationOptions(
      geometry: mapbox.Point(
          coordinates: mapbox.Position(
              userPosition!.coordinates.lng, userPosition!.coordinates.lat)),
      image: userIcon,
      iconSize: 0.4,
    ));

    // Add event marker
    final eventIcon = await _loadMarkerImage('images/marker-red.png');
    await pointAnnotationManager!.create(mapbox.PointAnnotationOptions(
      geometry: mapbox.Point(
          coordinates: mapbox.Position(
              destination.coordinates.lng, destination.coordinates.lat)),
      image: eventIcon,
      iconSize: 0.4,
    ));

    // Fetch and draw route
    await _fetchRoute(userPosition!, destination, selectedMode);
    if (routeCoordinates.isNotEmpty) {
      await polylineAnnotationManager!.create(mapbox.PolylineAnnotationOptions(
        geometry: mapbox.LineString(
          coordinates:
              routeCoordinates.map((c) => mapbox.Position(c[0], c[1])).toList(),
        ),
        lineColor: Colors.blue.value,
        lineWidth: 4.0,
      ));
    }
  }

  Future<Uint8List> _loadMarkerImage(String assetPath) async {
    final ByteData data = await rootBundle.load(assetPath);
    return data.buffer.asUint8List();
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(title: Text(widget.place)),
      drawer: MyDrawer(),
      body: isLoading
          ? const Center(child: CircularProgressIndicator())
          : mapbox.MapWidget(
              onMapCreated: (controller) {
                mapboxMap = controller;
              },
              cameraOptions: mapbox.CameraOptions(
                center: mapbox.Point(
                    coordinates: mapbox.Position(longitude, latitude)),
                zoom: 14.0,
              ),
            ),
      floatingActionButton: FloatingActionButton(
        onPressed: _drawRouteAndMarkers,
        child: const Icon(Icons.directions),
      ),
    );
  }
}