AppFlowy/frontend/app_flowy/lib/workspace/application/app/app_bloc.dart

import 'package:app_flowy/plugin/plugin.dart';
import 'package:app_flowy/startup/startup.dart';
import 'package:app_flowy/workspace/application/app/app_listener.dart';
import 'package:app_flowy/workspace/application/app/app_service.dart';
import 'package:app_flowy/workspace/presentation/home/menu/menu.dart';
import 'package:expandable/expandable.dart';
import 'package:flowy_sdk/log.dart';
import 'package:flowy_sdk/protobuf/flowy-folder-data-model/app.pb.dart';
import 'package:flowy_sdk/protobuf/flowy-folder-data-model/view.pb.dart';
import 'package:flowy_sdk/protobuf/flowy-error/errors.pb.dart';
import 'package:flutter/foundation.dart';
import 'package:freezed_annotation/freezed_annotation.dart';
import 'package:flutter_bloc/flutter_bloc.dart';
import 'package:dartz/dartz.dart';

part 'app_bloc.freezed.dart';

class AppBloc extends Bloc<AppEvent, AppState> {
  final App app;
  final AppService appService;
  final AppListener appListener;

  AppBloc({required this.app, required this.appService, required this.appListener}) : super(AppState.initial(app)) {
    on<AppEvent>((event, emit) async {
      await event.map(initial: (e) async {
        _startListening();
        await _loadViews(emit);
      }, createView: (CreateView value) async {
        await _createView(value, emit);
      }, didReceiveViewUpdated: (e) async {
        await _didReceiveViewUpdated(e.views, emit);
      }, delete: (e) async {
        await _deleteView(emit);
      }, rename: (e) async {
        await _renameView(e, emit);
      }, appDidUpdate: (e) async {
        emit(state.copyWith(app: e.app));
      });
    });
  }

  void _startListening() {
    appListener.start(
      viewsChanged: (result) {
        result.fold(
          (views) => add(AppEvent.didReceiveViewUpdated(views)),
          (error) => Log.error(error),
        );
      },
      appUpdated: (app) => add(AppEvent.appDidUpdate(app)),
    );
  }

  Future<void> _renameView(Rename e, Emitter<AppState> emit) async {
    final result = await appService.updateApp(appId: app.id, name: e.newName);
    result.fold(
      (l) => emit(state.copyWith(successOrFailure: left(unit))),
      (error) => emit(state.copyWith(successOrFailure: right(error))),
    );
  }

  Future<void> _deleteView(Emitter<AppState> emit) async {
    final result = await appService.delete(appId: app.id);
    result.fold(
      (unit) => emit(state.copyWith(successOrFailure: left(unit))),
      (error) => emit(state.copyWith(successOrFailure: right(error))),
    );
  }

  Future<void> _createView(CreateView value, Emitter<AppState> emit) async {
    final viewOrFailed = await appService.createView(
      appId: app.id,
      name: value.name,
      desc: value.desc,
      dataType: value.dataType,
      pluginType: value.pluginType,
    );
    viewOrFailed.fold(
      (view) => emit(state.copyWith(
        latestCreatedView: view,
        successOrFailure: left(unit),
      )),
      (error) {
        Log.error(error);
        emit(state.copyWith(successOrFailure: right(error)));
      },
    );
  }

  @override
  Future<void> close() async {
    await appListener.close();
    return super.close();
  }

  Future<void> _didReceiveViewUpdated(List<View> views, Emitter<AppState> emit) async {
    final latestCreatedView = state.latestCreatedView;
    AppState newState = state.copyWith(views: views);
    if (latestCreatedView != null) {
      final index = views.indexWhere((element) => element.id == latestCreatedView.id);
      if (index == -1) {
        newState = newState.copyWith(latestCreatedView: null);
      }
    }

    emit(newState);
  }

  Future<void> _loadViews(Emitter<AppState> emit) async {
    final viewsOrFailed = await appService.getViews(appId: app.id);
    viewsOrFailed.fold(
      (views) => emit(state.copyWith(views: views)),
      (error) {
        Log.error(error);
        emit(state.copyWith(successOrFailure: right(error)));
      },
    );
  }
}

@freezed
class AppEvent with _$AppEvent {
  const factory AppEvent.initial() = Initial;
  const factory AppEvent.createView(
    String name,
    String desc,
    PluginDataType dataType,
    PluginType pluginType,
  ) = CreateView;
  const factory AppEvent.delete() = Delete;
  const factory AppEvent.rename(String newName) = Rename;
  const factory AppEvent.didReceiveViewUpdated(List<View> views) = ReceiveViews;
  const factory AppEvent.appDidUpdate(App app) = AppDidUpdate;
}

@freezed
class AppState with _$AppState {
  const factory AppState({
    required App app,
    required List<View> views,
    View? latestCreatedView,
    required Either<Unit, FlowyError> successOrFailure,
  }) = _AppState;

  factory AppState.initial(App app) => AppState(
        app: app,
        views: [],
        successOrFailure: left(unit),
      );
}

class AppViewDataNotifier extends ChangeNotifier {
  List<View> _views = [];
  View? _selectedView;
  ExpandableController expandController = ExpandableController(initialExpanded: false);

  AppViewDataNotifier() {
    _setLatestView(getIt<MenuSharedState>().latestOpenView);
    getIt<MenuSharedState>().addLatestViewListener((view) {
      _setLatestView(view);
    });
  }

  void _setLatestView(View? view) {
    view?.freeze();
    _selectedView = view;
    _expandIfNeed();
  }

  View? get selectedView => _selectedView;

  set views(List<View> views) {
    if (_views != views) {
      _views = views;
      _expandIfNeed();
      notifyListeners();
    }
  }

  void _expandIfNeed() {
    if (_selectedView == null) {
      return;
    }

    if (!_views.contains(_selectedView!)) {
      return;
    }

    if (expandController.expanded == false) {
      // Workaround: Delay 150 milliseconds to make the smooth animation while expanding
      Future.delayed(const Duration(milliseconds: 150), () {
        expandController.expanded = true;
      });
    }
  }

  UnmodifiableListView<View> get views => UnmodifiableListView(_views);
}