feat: Implement a basic anime calendar

lib/src/ui/bloc/calendar_bloc.dart

@@ -0,0 +1,59 @@
+import 'dart:async';
+
+import 'package:anitrack/src/ui/bloc/anime_list_bloc.dart';
+import 'package:bloc/bloc.dart';
+import 'package:freezed_annotation/freezed_annotation.dart';
+import 'package:get_it/get_it.dart';
+import 'package:jikan_api/jikan_api.dart';
+
+part 'calendar_state.dart';
+part 'calendar_bloc.freezed.dart';
+part 'calendar_event.dart';
+
+class CalendarBloc extends Bloc<CalendarEvent, CalendarState> {
+  CalendarBloc() : super(CalendarState(false, 0, 0)) {
+    on<RefreshPerformedEvent>(_onRefreshPerformed);
+  }
+
+  Future<void> _onRefreshPerformed(
+    RefreshPerformedEvent event,
+    Emitter<CalendarState> emit,
+  ) async {
+    emit(
+      state.copyWith(
+        refreshing: true,
+        refreshingCount: 0,
+        refreshingTotal: 0,
+      ),
+    );
+
+    final al = GetIt.I.get<AnimeListBloc>();
+    final animes = al.state.animes.where((anime) => anime.airing);
+    emit(
+      state.copyWith(
+        refreshing: true,
+        refreshingCount: 0,
+        refreshingTotal: animes.length,
+      ),
+    );
+
+    for (final anime in animes) {
+      emit(state.copyWith(refreshingCount: state.refreshingCount + 1));
+
+      final apiData = await Jikan().getAnime(int.parse(anime.id));
+      if (!apiData.airing) {
+        al.add(
+          AnimeUpdatedEvent(
+            anime.copyWith(airing: false, broadcastDay: null),
+            commit: true,
+          ),
+        );
+      }
+
+      // Prevent hammering Jikan
+      await Future<void>.delayed(const Duration(milliseconds: 500));
+    }
+
+    emit(state.copyWith(refreshing: false));
+  }
+}