import 'dart:async';
import 'dart:typed_data';
import 'package:app_flowy/workspace/domain/i_app.dart';
import 'package:dartz/dartz.dart';
import 'package:flowy_infra/flowy_logger.dart';
import 'package:flowy_sdk/dispatch/dispatch.dart';
import 'package:flowy_sdk/protobuf/flowy-observable/subject.pb.dart';
import 'package:flowy_sdk/protobuf/flowy-workspace/app_create.pb.dart';
import 'package:flowy_sdk/protobuf/flowy-workspace/app_query.pb.dart';
import 'package:flowy_sdk/protobuf/flowy-workspace/errors.pb.dart';
import 'package:flowy_sdk/protobuf/flowy-workspace/observable.pb.dart';
import 'package:flowy_sdk/protobuf/flowy-workspace/view_create.pb.dart';
import 'package:flowy_sdk/protobuf/flowy-workspace/view_create.pbenum.dart';
import 'package:flowy_sdk/rust_stream.dart';
import 'helper.dart';

class AppRepository {
  String appId;
  AppRepository({
    required this.appId,
  });

  Future<Either<App, WorkspaceError>> getAppDesc() {
    final request = QueryAppRequest.create()
      ..appId = appId
      ..readBelongings = false;

    return WorkspaceEventReadApp(request).send();
  }

  Future<Either<View, WorkspaceError>> createView(
      String name, String desc, ViewType viewType) {
    final request = CreateViewRequest.create()
      ..belongToId = appId
      ..name = name
      ..desc = desc
      ..viewType = viewType;

    return WorkspaceEventCreateView(request).send();
  }

  Future<Either<List<View>, WorkspaceError>> getViews() {
    final request = QueryAppRequest.create()
      ..appId = appId
      ..readBelongings = true;

    return WorkspaceEventReadApp(request).send().then((result) {
      return result.fold(
        (app) => left(app.belongings.items),
        (error) => right(error),
      );
    });
  }
}

class AppWatchRepository {
  StreamSubscription<ObservableSubject>? _subscription;
  AppCreateViewCallback? _createView;
  AppDeleteViewCallback? _deleteView;
  AppUpdatedCallback? _update;
  late WorkspaceObservableParser _extractor;
  String appId;

  AppWatchRepository({
    required this.appId,
  });

  void startWatching(
      {AppCreateViewCallback? createView,
      AppDeleteViewCallback? deleteView,
      AppUpdatedCallback? update}) {
    _createView = createView;
    _deleteView = deleteView;
    _update = update;
    _extractor =
        WorkspaceObservableParser(id: appId, callback: _bservableCallback);
    _subscription =
        RustStreamReceiver.listen((observable) => _extractor.parse(observable));
  }

  void _bservableCallback(
      WorkspaceObservable ty, Either<Uint8List, WorkspaceError> result) {
    switch (ty) {
      case WorkspaceObservable.AppCreateView:
        if (_createView != null) {
          result.fold(
            (payload) {
              final repeatedView = RepeatedView.fromBuffer(payload);
              _createView!(left(repeatedView.items));
            },
            (error) => _createView!(right(error)),
          );
        }
        break;
      case WorkspaceObservable.AppDeleteView:
        if (_deleteView != null) {
          result.fold(
            (payload) => _deleteView!(
              left(RepeatedView.fromBuffer(payload).items),
            ),
            (error) => _deleteView!(right(error)),
          );
        }
        break;
      case WorkspaceObservable.AppUpdated:
        if (_update != null) {
          result.fold(
            (payload) {
              final app = App.fromBuffer(payload);
              _update!(app.name, app.desc);
            },
            (error) => Log.error(error),
          );
        }
        break;
      default:
        break;
    }
  }

  Future<void> close() async {
    await _subscription?.cancel();
  }
}