import 'dart:async';
import 'dart:convert';

import 'package:flutter_secure_storage/flutter_secure_storage.dart';
import 'package:logger/logger.dart';
import 'package:rxdart/rxdart.dart';
import 'package:seshat/config/constants.dart';
import 'package:seshat/domain/models/owner.dart';
import 'package:web_socket_channel/web_socket_channel.dart';

/// API Client to manages connections to WebSockets
class WebsocketClient {
  /// Storage to access JWT
  FlutterSecureStorage? _secureStorage;

  /// Raw channel of data from WebSocket
  WebSocketChannel? _channel;

  /// Global WebSocket Stream
  final BehaviorSubject<dynamic> _baseController = BehaviorSubject();

  /// WebSocket Stream dedicated to [Owner] entries
  final BehaviorSubject<Owner> _ownersController = BehaviorSubject<Owner>(
    sync: true,
  );

  /// Subscription to [_baseController]
  late final StreamSubscription sub;
  Logger log = Logger(
    printer: PrettyPrinter(
      colors: true,
      lineLength: 100,
      methodCount: 0,
      dateTimeFormat: DateTimeFormat.dateAndTime,
    ),
  );

  /// Gets a stream of [Owner]
  Stream<Owner> get owners => _ownersController.stream;

  /// Initializes connection to the [_secureStorage]
  Future<void> _initStore() async {
    _secureStorage ??= const FlutterSecureStorage();
  }

  /// Connects to the websocket
  Future<void> connect() async {
    final url = "wss://$apiBasePath/ws";
    log.i("Webocket: $url");
    await _initStore();
    if (_channel != null) return;

    _channel = WebSocketChannel.connect(Uri.parse(url));

    await _channel!.ready;
    var token = await _secureStorage!.read(key: "token");

    _channel!.sink.add(jsonEncode({"token": "$token"}));
    _channel!.stream.listen((message) {
      _baseController.add(message);
    });
    var data = await _baseController.stream.first;
    var result = jsonDecode(data);

    if (result["type"] == "auth_success") {
      sub = _baseController.stream.listen(
        (message) {
          final Map<String, dynamic> data = jsonDecode(message);
          switch (data["type"]) {
            case "new_owner":
              final owner = Owner.fromJSON(data["data"]);
              _ownersController.add(owner);
              break;
            default:
          }
        },
        onDone: _handleDisconnect,
        onError: (error) {
          _handleDisconnect();
        },
      );
    }
  }

  /// Disconnects from the websocket
  void _handleDisconnect() {
    sub.cancel();
    _channel = null;
  }

  /// Closes all connections
  void dispose() {
    sub.cancel();
    _channel?.sink.close();
    _ownersController.close();
  }
}