mobile-app/lib/presentation/screens/notification/sc_notification.dart

import 'package:farm_tpf/custom_model/NotificationDTO.dart';
import 'package:farm_tpf/data/repository/repository.dart';
import 'package:farm_tpf/presentation/custom_widgets/bottom_loader.dart';
import 'package:farm_tpf/presentation/custom_widgets/dash_line_widget.dart';
import 'package:farm_tpf/presentation/custom_widgets/loading_list_page.dart';
import 'package:farm_tpf/presentation/screens/notification/update_count_noti_bloc.dart';
import 'package:farm_tpf/presentation/screens/plot_detail/sc_plot_detail.dart';
import 'package:farm_tpf/utils/NotificationsBloc.dart';
import 'package:farm_tpf/utils/const_icons.dart';
import 'package:farm_tpf/utils/pref.dart';
import 'package:flutter/material.dart';
import 'package:flutter_bloc/flutter_bloc.dart';
import 'package:farm_tpf/utils/formatter.dart';
import 'package:flutter_svg/svg.dart';

import 'bloc/noti_bloc.dart';

class NotificationScreen extends StatefulWidget {
  @override
  _NotificationScreenState createState() => _NotificationScreenState();
}

class _NotificationScreenState extends State<NotificationScreen> {
  var notiBloc = NotiBloc(repository: Repository());

  final _scrollController = ScrollController();
  final _scrollThreshold = 250.0;
  List<NotificationDTO> currentItems = new List<NotificationDTO>();
  int latestId = 0;
  int currentPage = 0;
  bool currentHasReachedMax = true;
  bool isUpdatingFromApi = true;
  Stream<LocalNotification> _notificationsStream;

  var pref = LocalPref();
  var token;
  Future<Null> getSharedPrefs() async {
    _scrollController.addListener(() {
      final maxScroll = _scrollController.position.maxScrollExtent;
      final currentScroll = _scrollController.position.pixels;
      if (maxScroll - currentScroll < _scrollThreshold) {
        notiBloc.add(DataFetched());
      }
    });
    token = await pref.getString(DATA_CONST.TOKEN_KEY);
  }

  @override
  void initState() {
    getSharedPrefs();
    notiBloc.add(DataFetched());
    _notificationsStream = NotificationsBloc.instance.notificationsStream;
    _notificationsStream.listen((notification) {
      updateCountNotiBloc.getNotifications((data) {}, (err) {});
      print('Notification: $notification');
      notiBloc.add(OnRefresh());
    });
    super.initState();
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      backgroundColor: Colors.white,
      body: BlocBuilder<NotiBloc, NotiState>(
        cubit: notiBloc,
        builder: (context, state) {
          if (state is NotiFailure) {
            return Center(child: Text(state.errorString));
          } else if (state is NotiSuccess) {
            updateCountNotiBloc.getNotifications((data) {}, (err) {});
            if (state.items.isEmpty) {
              return SafeArea(
                child: Column(
                  crossAxisAlignment: CrossAxisAlignment.start,
                  children: [
                    SizedBox(
                      height: 8,
                    ),
                    Padding(
                      padding: const EdgeInsets.all(8.0),
                      child: Text('Thông báo',
                          style: TextStyle(
                              fontWeight: FontWeight.w500, fontSize: 22)),
                    ),
                    Expanded(
                      child: Center(child: Text("Không có thông báo")),
                    ),
                  ],
                ),
              );
            }
            currentItems = List<NotificationDTO>.from(state.items);
            currentPage = state.page;
            currentHasReachedMax = state.hasReachedMax;

            return SafeArea(
              child: Column(
                children: <Widget>[
                  Container(
                      padding: EdgeInsets.all(8),
                      color: Colors.white,
                      child: Row(
                        children: [
                          SizedBox(
                            height: 8,
                          ),
                          Expanded(
                              child: Text(
                            'Thông báo',
                            style: TextStyle(
                                fontWeight: FontWeight.w500, fontSize: 22),
                          )),
                          FlatButton(
                              onPressed: () {
                                notiBloc.add(
                                    MarkAllNotificationUpdate(status: "1"));
                              },
                              child: Text('Đánh dấu đã đọc tất cả',
                                  style: TextStyle(
                                      fontWeight: FontWeight.normal,
                                      fontSize: 14,
                                      color: Colors.blue)))
                        ],
                      )),
                  Expanded(
                      child: RefreshIndicator(
                          child: ListView.builder(
                            physics: AlwaysScrollableScrollPhysics(),
                            itemBuilder: (BuildContext context, int index) {
                              return index >= state.items.length
                                  ? BottomLoader()
                                  : ItemInfinityWidget(
                                      notiBloc: notiBloc,
                                      unread: state.unread,
                                      read: state.read,
                                      currentItems: currentItems,
                                      item: state.items[index],
                                      currentPage: state.page,
                                      currentReachedMax: state.hasReachedMax,
                                    );
                            },
                            itemCount: state.hasReachedMax
                                ? state.items.length
                                : state.items.length + 1,
                            controller: _scrollController,
                          ),
                          onRefresh: () async {
                            notiBloc.add(OnRefresh());
                          }))
                ],
              ),
            );
          } else if (state is NotiLoadding) {
            return Center(
              child: LoadingListPage(),
            );
          }
          return Container();
        },
      ),
    );
  }

  @override
  void dispose() {
    _scrollController.dispose();
    super.dispose();
  }
}

class ItemInfinityWidget extends StatelessWidget {
  final int unread;
  final int read;
  final NotificationDTO item;
  final List<NotificationDTO> currentItems;
  final int currentPage;
  final bool currentReachedMax;
  final NotiBloc notiBloc;

  const ItemInfinityWidget(
      {Key key,
      @required this.unread,
      @required this.read,
      @required this.currentItems,
      @required this.item,
      @required this.currentPage,
      @required this.currentReachedMax,
      @required this.notiBloc})
      : super(key: key);

  @override
  Widget build(BuildContext context) {
    var type;
    try {
      type = int.parse(item.type);
    } catch (_) {
      type = -1;
    }
    return Column(
      children: [
        GestureDetector(
            child: Container(
                margin: EdgeInsets.all(4.0),
                child: Column(
                  children: [
                    ListTile(
                        title: Text(item.subject),
                        subtitle: Column(
                          crossAxisAlignment: CrossAxisAlignment.start,
                          children: <Widget>[
                            Text(item.message),
                            Row(children: [
                              Icon(Icons.access_time,
                                  color: item.isRead == 1
                                      ? Colors.grey
                                      : Colors.blue,
                                  size: 18),
                              SizedBox(
                                width: 4,
                              ),
                              Text(item.sendDate.format_DDMMYY_HHmm(),
                                  style: TextStyle(
                                      color: item.isRead == 1
                                          ? Colors.grey
                                          : Colors.blue))
                            ]),
                          ],
                        ),
                        leading: SvgPicture.asset(AppIcons.icNotificationItem)),
                  ],
                )),
            onTap: () {
              if (item.contents == "ENV_UPDATE") {
                Navigator.push(
                    context,
                    MaterialPageRoute(
                        builder: (BuildContext context) => PlotDetailScreen(
                              cropType: type,
                              cropId: item.tbCropId,
                              initialIndex: 0,
                            ))).then((value) {
                  if (item.isRead == 0) {
                    _updateReadNotification(
                        context: context,
                        unread: unread,
                        read: read,
                        item: item,
                        currentItems: currentItems,
                        currentPage: currentPage,
                        currentReachedMax: currentReachedMax);
                  }
                });
              } else if (item.contents == "PIC_UPDATE") {
                Navigator.push(
                    context,
                    MaterialPageRoute(
                        builder: (BuildContext context) => PlotDetailScreen(
                              cropType: type,
                              cropId: item.tbCropId,
                              initialIndex: 1,
                            ))).then((value) {
                  if (item.isRead == 0) {
                    _updateReadNotification(
                        context: context,
                        unread: unread,
                        read: read,
                        item: item,
                        currentItems: currentItems,
                        currentPage: currentPage,
                        currentReachedMax: currentReachedMax);
                  }
                });
              } else {}
            }),
        Container(
            padding: EdgeInsets.only(left: 16, right: 16),
            child: DashLineWidget())
      ],
    );
  }

  _updateReadNotification(
      {BuildContext context,
      int unread,
      int read,
      NotificationDTO item,
      List<NotificationDTO> currentItems,
      int currentPage,
      bool currentReachedMax}) {
    List<NotificationDTO> updatedItems = new List<NotificationDTO>();
    currentItems.forEach((e) {
      if (e.id == item.id) {
        e.isRead = 1;
      } else {}
      updatedItems.add(NotificationDTO.clone(e));
    });

    notiBloc.add(OnUpdate<NotificationDTO>(
        unread: unread - 1,
        read: read + 1,
        currentItemId: item.id,
        currentItems: updatedItems,
        currentPage: currentPage,
        hasReachedMax: currentReachedMax));
  }
}