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/loading_list_page.dart';
import 'package:farm_tpf/presentation/screens/plot_detail/sc_plot_detail.dart';
import 'package:farm_tpf/presentation/screens/plot_detail/sc_plot_information.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 'bloc/noti_bloc.dart';

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

class _NotificationScreenState extends State<NotificationScreen> {
  @override
  Widget build(BuildContext context) {
    return BlocProvider(
      create: (context) =>
          NotiBloc(repository: Repository())..add(DataFetched()),
      child: HoldInfinityWidget(),
    );
  }
}

class HoldInfinityWidget extends StatelessWidget {
  final GlobalKey<ScaffoldState> _scaffoldKey = new GlobalKey<ScaffoldState>();
  @override
  Widget build(BuildContext context) {
    return Scaffold(
        key: _scaffoldKey,
        appBar: AppBar(
          centerTitle: true,
          title: Text("Thông báo"),
          actions: <Widget>[
            IconButton(
                icon: Icon(Icons.done_all),
                onPressed: () {
                  BlocProvider.of<NotiBloc>(context)
                      .add(MarkAllNotificationUpdate(status: "1"));
                })
          ],
        ),
        body: InfinityView());
  }
}

class InfinityView extends StatefulWidget {
  @override
  _InfinityViewState createState() => _InfinityViewState();
}

class _InfinityViewState extends State<InfinityView> {
  final _scrollController = ScrollController();
  final _scrollThreshold = 250.0;
  NotiBloc _notiBloc;
  List<NotificationDTO> currentItems = new List<NotificationDTO>();
  int latestId = 0;
  int currentPage = 0;
  bool currentHasReachedMax = true;
  bool isUpdatingFromApi = true;

  var pref = LocalPref();
  // final SocketService socketService = injector.get<SocketService>();
  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);
    // socketService.initial(token);
    _notiBloc = BlocProvider.of<NotiBloc>(context);
  }

  @override
  void initState() {
    getSharedPrefs();
    super.initState();
  }

  @override
  Widget build(BuildContext context) {
    return BlocConsumer<NotiBloc, NotiState>(
      listener: (context, state) {
        //Handle Socket
        /*
        if (state is NotiLoadding) {
          isUpdatingFromApi = true;
        }
        if (state is NotiSuccess) {
          currentItems = List<NotificationDTO>.from(state.items);
          latestId = int.parse(currentItems[0].id) > latestId
              ? int.parse(currentItems[0].id)
              : latestId;
          socketService.createSocketNotificationConnection(latestId, (data) {
            print("receive data");
            if (isUpdatingFromApi == false) {
              print("Update from socket");
              var notis =
                  NotificationObjectDTO.fromJson(data, NotificationDTO());
              _notiBloc.add(ReceiveDataFromSocket(
                  currentItems: currentItems,
                  page: currentPage,
                  hasReachedMax: currentHasReachedMax,
                  updatedItemObject: notis));
            } else {
              //dont need update from socket
              print("dont need update from socket");
            }
          }, (error) {});
          isUpdatingFromApi = false;
        }
        */
      },
      builder: (context, state) {
        if (state is NotiFailure) {
          return Center(child: Text(state.errorString));
        }
        if (state is NotiSuccess) {
          if (state.items.isEmpty) {
            return Center(child: Text("Dữ liệu rỗng"));
          }
          currentItems = List<NotificationDTO>.from(state.items);
          currentPage = state.page;
          currentHasReachedMax = state.hasReachedMax;
          return Column(
            children: <Widget>[
              Container(
                child:
                    countNotification(unread: state.unread, read: state.read),
              ),
              Expanded(
                  child: RefreshIndicator(
                      child: ListView.builder(
                        itemBuilder: (BuildContext context, int index) {
                          return index >= state.items.length
                              ? BottomLoader()
                              : ItemInfinityWidget(
                                  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());
                      }))
            ],
          );
        }
        return Center(
          child: LoadingListPage(),
        );
      },
    );
  }

  Widget countNotification({num unread, num read}) {
    return Container(
      child: Row(
        mainAxisAlignment: MainAxisAlignment.center,
        mainAxisSize: MainAxisSize.max,
        children: <Widget>[
          Expanded(
              child: OutlineButton(
                  child: RichText(
                      text: TextSpan(
                          text: "Chưa đọc ",
                          style: TextStyle(
                              color: Colors.black, fontWeight: FontWeight.bold),
                          children: <TextSpan>[
                        TextSpan(
                            text: "($unread)",
                            style: TextStyle(color: Colors.blue)),
                      ])),
                  onPressed: () {})),
          Expanded(
              child: OutlineButton(
                  child: RichText(
                      text: TextSpan(
                          text: "Đã đọc ",
                          style: TextStyle(
                              color: Colors.black, fontWeight: FontWeight.bold),
                          children: <TextSpan>[
                        TextSpan(
                            text: "($read)",
                            style: TextStyle(color: Colors.grey)),
                      ])),
                  onPressed: () {}))
        ],
      ),
    );
  }

  @override
  void dispose() {
    _scrollController.dispose();
    // socketService.disconnect();
    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;

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

  @override
  Widget build(BuildContext context) {
    return GestureDetector(
        child: Card(
            margin: EdgeInsets.all(4.0),
            child: ListTile(
                title: Text(item.subject),
                subtitle: Column(
                  crossAxisAlignment: CrossAxisAlignment.start,
                  children: <Widget>[
                    Text(item.message),
                    Text(
                      item.sendDate.format_DDMMYY_HHmm(),
                      style: TextStyle(
                          color: item.isRead == 1 ? Colors.grey : Colors.blue),
                    ),
                  ],
                ),
                leading: Icon(
                  Icons.notifications_active,
                  color: item.isRead == 1 ? Colors.grey : Colors.blue,
                ))),
        onTap: () {
          if (item.contents == "ENV_UPDATE") {
            Navigator.push(
                context,
                MaterialPageRoute(
                    builder: (BuildContext context) =>
                        PlotDetailScreen(cropId: item.tbCropId))).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) => PlotInformationScreen(
                          cropId: item.tbCropId,
                        ))).then((value) {
              if (item.isRead == 0) {
                _updateReadNotification(
                    context: context,
                    unread: unread,
                    read: read,
                    item: item,
                    currentItems: currentItems,
                    currentPage: currentPage,
                    currentReachedMax: currentReachedMax);
              }
            });
          } else {}
        });
  }

  _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));
    });

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