cloudsolutions-atoms/lib/controllers/providers/api/notifications_provider.dart

import 'dart:convert';

import 'package:flutter/cupertino.dart';
import 'package:http/http.dart';
import 'package:test_sa/controllers/api_routes/api_manager.dart';
import 'package:test_sa/controllers/api_routes/urls.dart';
import 'package:test_sa/models/system_notification_model.dart';
import 'package:test_sa/models/user.dart';

class NotificationsProvider extends ChangeNotifier {
  // number of items call in each request
  final pageItemNumber = 12;

  //reset provider data
  void reset() {
    notifications = [];
    nextPage = true;
    stateCode = null;
  }

  // state code of current request to defied error message
  // like 400 customer request failed
  // 500 service not available
  int stateCode;

  // true if there is next page in product list and false if not
  bool nextPage = true;

  // list of user requests
  List<SystemNotificationModel> notifications = [];

  // when requests in-process _loading = true
  // done _loading = true
  // failed _loading = false
  bool isLoading;

  /// return -2 if request in progress
  /// return -1 if error happen when sending request
  /// return state code if request complete may be 200, 404 or 403
  /// for more details check http state manager
  /// lib\controllers\http_status_manger\http_status_manger.dart
  Future<int> getSystemNotifications({User user, bool resetProvider = false}) async {
    if (isLoading == true) return -2;

    if (resetProvider) {
      reset();
    }
    isLoading = true;
    notifyListeners();
    Response response;
    try {
      final Map<String, dynamic> body = {"pageSize": pageItemNumber, "pageNumber": notifications.length ~/ pageItemNumber + 1, "userId": user.userID};
      response = await ApiManager.instance.post(URLs.getSystemNotifications, body: body);

      stateCode = response.statusCode;
      if (response.statusCode >= 200 && response.statusCode < 300) {
        // client's request was successfully received
        //  List requestsListJson = json.decode(utf8.decode(response.bodyBytes));

        List requestsListJson = json.decode(response.body)["data"];
        List<SystemNotificationModel> _serviceRequestsPage = requestsListJson.map((request) => SystemNotificationModel.fromJson(request)).toList();
        if (notifications == null) notifications = [];
        notifications.addAll(_serviceRequestsPage);
        if (_serviceRequestsPage.length == pageItemNumber) {
          nextPage = true;
        } else {
          nextPage = false;
        }
      }
      isLoading = false;
      notifyListeners();
      return response.statusCode;
    } catch (error) {
      print(error);
      isLoading = false;
      stateCode = -1;
      notifyListeners();
      return -1;
    }
  }

  /// return -2 if request in progress
  /// return -1 if error happen when sending request
  /// return state code if request complete may be 200, 404 or 403
  /// for more details check http state manager
  /// lib\controllers\http_status_manger\http_status_manger.dart
  Future<List<SystemNotificationModel>> getRecentNotifications({
    @required String host,
    @required User user,
  }) async {
    Response response;
    //userId = 397.toString(); // testing id to view data

    try {
      response = await get(Uri.parse(host + URLs.getSystemNotifications + "?uid=${user.id}&token=${user.token}"), headers: {"Content-Type": "application/json; charset=utf-8"});

      stateCode = response.statusCode;
      if (response.statusCode >= 200 && response.statusCode < 300) {
        // client's request was successfully received
        List requestsListJson = json.decode(utf8.decode(response.bodyBytes));
        List<SystemNotificationModel> _recentNotifications = requestsListJson.map((request) => SystemNotificationModel.fromJson(request)).toList();
        return _recentNotifications;
      }
      return null;
    } catch (error) {
      return null;
    }
  }
}