Add anonymous subscriptions bloc and allow to subscribe to communitie…

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lib/community/bloc/anonymous_subscriptions_bloc.dart

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+
+import 'dart:async';
+import 'package:bloc/bloc.dart';
+import 'package:bloc_concurrency/bloc_concurrency.dart';
+import 'package:equatable/equatable.dart';
+import 'package:lemmy_api_client/v3.dart';
+import 'package:stream_transform/stream_transform.dart';
+import 'package:thunder/community/helpers/anonymous_subscriptions_helper.dart';
+import 'package:thunder/community/models/anonymous_subscriptions.dart';
+
+part 'anonymous_subscriptions_event.dart';
+part 'anonymous_subscriptions_state.dart';
+
+const throttleDuration = Duration(seconds: 1);
+
+EventTransformer<E> throttleDroppable<E>(Duration duration) {
+  return (events, mapper) => droppable<E>().call(events.throttle(duration), mapper);
+}
+
+class AnonymousSubscriptionsBloc extends Bloc<AnonymousSubscriptionsEvent, AnonymousSubscriptionsState>{
+  AnonymousSubscriptionsBloc() : super(const AnonymousSubscriptionsState()){
+    on<GetSubscribedCommunitiesEvent>(
+        _getSubscribedCommunities,
+        transformer: throttleDroppable(throttleDuration)
+    );
+
+    on<AddSubscriptionsEvent>(
+        _addSubscriptions,
+        transformer: throttleDroppable(throttleDuration)
+    );
+
+    on<DeleteSubscriptionsEvent>(
+        _deleteSubscriptions,
+        transformer: throttleDroppable(throttleDuration)
+    );
+  }
+
+  FutureOr<void> _deleteSubscriptions(DeleteSubscriptionsEvent event, Emitter<AnonymousSubscriptionsState> emit) async {
+    try {
+      await AnonymousSubscriptions.deleteCommunities(event.ids);
+      emit(state.copyWith(
+        status: AnonymousSubscriptionsStatus.success,
+        subscriptions: [...state.subscriptions]..removeWhere((e) => event.ids.contains(e.id)),
+        ids: {...state.ids}..removeAll(event.ids),
+      ));
+      emit(state.copyWith(status: AnonymousSubscriptionsStatus.success));
+    } catch (e) {
+      emit(state.copyWith(status: AnonymousSubscriptionsStatus.failure, errorMessage: e.toString()));
+    }
+  }
+
+  FutureOr<void> _addSubscriptions(AddSubscriptionsEvent event, Emitter<AnonymousSubscriptionsState> emit) async {
+    try {
+      await insertSubscriptions(event.communities);
+      emit(state.copyWith(
+          status: AnonymousSubscriptionsStatus.success,
+          subscriptions: [...state.subscriptions, ...event.communities],
+          ids: {...state.ids}..addAll(event.communities.map((e) => e.id))
+      ));
+
+    } catch (e) {
+      emit(state.copyWith(status: AnonymousSubscriptionsStatus.failure, errorMessage: e.toString()));
+    }
+  }
+
+  Future<void> _getSubscribedCommunities(GetSubscribedCommunitiesEvent event, Emitter<AnonymousSubscriptionsState> emit) async {
+    emit(const AnonymousSubscriptionsState(status: AnonymousSubscriptionsStatus.loading));
+    try {
+      List<CommunitySafe> subscribedCommunities = await getSubscriptions();
+      emit(state.copyWith(
+        status: AnonymousSubscriptionsStatus.success,
+        subscriptions: subscribedCommunities,
+        ids: subscribedCommunities.map((e) => e.id).toSet(),
+      ));
+    } catch (e) {
+      emit(state.copyWith(status: AnonymousSubscriptionsStatus.failure, errorMessage: e.toString()));
+    }
+  }
+}

lib/community/bloc/anonymous_subscriptions_event.dart

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+part of 'anonymous_subscriptions_bloc.dart';
+
+abstract class AnonymousSubscriptionsEvent extends Equatable {
+  const AnonymousSubscriptionsEvent();
+
+  @override
+  List<Object> get props => [];
+}
+
+class GetSubscribedCommunitiesEvent extends AnonymousSubscriptionsEvent {}
+
+class AddSubscriptionsEvent extends AnonymousSubscriptionsEvent {
+  final Set<CommunitySafe> communities;
+
+  const AddSubscriptionsEvent({required this.communities});
+}
+
+class DeleteSubscriptionsEvent extends AnonymousSubscriptionsEvent {
+  final Set<int> ids;
+
+  const DeleteSubscriptionsEvent({required this.ids});
+}

lib/community/bloc/anonymous_subscriptions_state.dart

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+part of 'anonymous_subscriptions_bloc.dart';
+
+enum AnonymousSubscriptionsStatus { initial, loading, refreshing, success, empty, failure }
+
+class AnonymousSubscriptionsState extends Equatable {
+  const AnonymousSubscriptionsState({
+    this.status = AnonymousSubscriptionsStatus.initial,
+    this.subscriptions = const [],
+    this.ids = const {},
+    this.errorMessage,
+  });
+
+  final AnonymousSubscriptionsStatus status;
+  final String? errorMessage;
+  final List<CommunitySafe> subscriptions;
+  final Set<int> ids;
+
+
+  AnonymousSubscriptionsState copyWith({
+    AnonymousSubscriptionsStatus? status,
+    List<CommunitySafe>? subscriptions,
+    Set<int>? ids,
+    String? errorMessage,
+  }) {
+    return AnonymousSubscriptionsState(
+      status: status ?? this.status,
+      ids: ids?? this.ids,
+      subscriptions: subscriptions ?? this.subscriptions,
+      errorMessage: errorMessage ?? this.errorMessage,
+    );
+  }
+
+  @override
+  List<Object?> get props => [status, subscriptions, ids, errorMessage];
+}

lib/community/helpers/anonymous_subscriptions_helper.dart

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+import 'package:lemmy_api_client/v3.dart';
+
+import '../models/anonymous_subscriptions.dart';
+
+Future<List<CommunitySafe>> getSubscriptions() async {
+  List<Community> subscribedCommunities = await AnonymousSubscriptions.getSubscribedCommunities();
+  return subscribedCommunities.map((e) => e.toCommunitySafe).toList();
+}
+
+Future<void> insertSubscriptions(Set<CommunitySafe> communities) async {
+  Set<Community> newCommunities = communities.map((e) => e.toCommunity).toSet();
+  await AnonymousSubscriptions.insertCommunities(newCommunities);
+}
+
+extension on Community {
+  CommunitySafe get toCommunitySafe {
+    return CommunitySafe(
+        id: id,
+        name: name,
+        title: title,
+        removed: false,
+        published: DateTime.now(),
+        deleted: false,
+        nsfw: false,
+        actorId: actorId,
+        local: false,
+        icon: icon,
+        instanceHost: "lemmy.world");
+  }
+}
+
+extension on CommunitySafe {
+  Community get toCommunity {
+    return Community(
+        id: id,
+        name: name,
+        title: title,
+        icon: icon,
+        actorId: actorId);
+  }
+}