mobile-app/lib/data/repository/authentication_repository.dart

import 'dart:async';

import 'package:farm_tpf/custom_model/user.dart';
import 'package:farm_tpf/custom_model/user_request.dart';
import 'package:farm_tpf/data/api/dio_provider.dart';
import 'package:farm_tpf/data/api/rest_client.dart';
import 'package:farm_tpf/utils/const_common.dart';
import 'package:farm_tpf/utils/pref.dart';

enum AuthenticationStatus { unknown, authenticated, unauthenticated }

class AuthenticationRepository {
  final _controller = StreamController<AuthenticationStatus>();
  final dio = DioProvider.instance();
  final pref = LocalPref();

  Stream<AuthenticationStatus> get status async* {
    try {
      var token = await pref.getString(DATA_CONST.TOKEN_KEY);
      var expiredTime = await pref.getString(DATA_CONST.EXPIRED_TIME);
      int currentTime = DateTime.now().millisecondsSinceEpoch;
      bool isNotExpired =
          (currentTime - int.tryParse(expiredTime)) < ConstCommon.kExpiredTime;

      if (token.isNotEmpty && isNotExpired) {
        yield AuthenticationStatus.authenticated;
      } else {
        yield AuthenticationStatus.unauthenticated;
      }
    } catch (_) {
      yield AuthenticationStatus.unauthenticated;
    }
    yield* _controller.stream;
  }

  Future<User> signInWithCredentials(String username, String password) {
    final client = RestClient(dio);
    var result =
        client.login(UserRequest(username: username, password: password));
    return result;
  }

  void logOut() {
    pref.saveString(DATA_CONST.TOKEN_KEY, "");
    _controller.add(AuthenticationStatus.unauthenticated);
  }

  void dispose() => _controller.close();
}