improved performance and battery usage on older devices

lib/view/pages/timetable/data/calendar_logic.dart

@@ -1,7 +1,7 @@
-import 'package:rrule/rrule.dart';
 import 'package:syncfusion_flutter_calendar/calendar.dart';
 
 import '../../../../extensions/date_time.dart';
+import '../../../../utils/recurrence_occurrences.dart';
 import 'arbitrary_appointment.dart';
 import 'calendar_layout.dart';
 import 'lesson_period_schedule.dart';
@@ -103,7 +103,6 @@ partitionAppointmentsForWeek(
       continue;
     }
     try {
-      final parsed = RecurrenceRule.fromString(rule);
       final anchorUtc = a.startTime.toUtc();
       final duration = a.endTime.difference(a.startTime);
       // Day-keyed set of exception dates so occurrences scheduled for one
@@ -112,9 +111,12 @@ partitionAppointmentsForWeek(
       final exceptionDayKeys = (a.recurrenceExceptionDates ?? const <DateTime>[])
           .map((d) => '${d.year}-${d.month}-${d.day}')
           .toSet();
-      for (final occUtc in parsed.getInstances(start: anchorUtc)) {
-        if (!occUtc.isBefore(weekEndUtc)) break;
-        if (occUtc.isBefore(weekStartUtc)) continue;
+      for (final occUtc in RecurrenceOccurrences.between(
+        rule,
+        anchorUtc,
+        weekStartUtc,
+        weekEndUtc,
+      )) {
         final occLocal = occUtc.toLocal();
         if (exceptionDayKeys.contains(
           '${occLocal.year}-${occLocal.month}-${occLocal.day}',

lib/view/pages/timetable/timetable.dart

@@ -266,11 +266,12 @@ class _ViewingBanner extends StatelessWidget {
   @override
   Widget build(BuildContext context) {
     final theme = Theme.of(context);
-    final isFavorite = context
-        .watch<SettingsCubit>()
-        .val()
-        .timetableFavoritesSettings
-        .isFavorite(element.type, element.id);
+    final isFavorite = context.select(
+      (SettingsCubit c) => c.state.timetableFavoritesSettings.isFavorite(
+        element.type,
+        element.id,
+      ),
+    );
 
     final onColor = theme.colorScheme.onSecondaryContainer;
     // Compact icon button: ~32px square, no extra padding, so the banner stays

lib/view/pages/timetable/widgets/timetable_calendar_view.dart

@@ -7,10 +7,10 @@ import '../../../../extensions/date_time.dart';
 import '../../../../state/app/modules/capabilities/bloc/capabilities_cubit.dart';
 import '../../../../state/app/modules/settings/bloc/settings_cubit.dart';
 import '../../../../state/app/modules/timetable/bloc/timetable_state.dart';
-import '../../../../storage/timetable_settings.dart';
 import '../data/arbitrary_appointment.dart';
 import '../data/lesson_period_schedule.dart';
 import '../data/timetable_appointment_factory.dart';
+import '../data/timetable_name_mode.dart';
 import 'custom_workweek_calendar.dart';
 import 'special_regions_builder.dart';
 
@@ -51,9 +51,10 @@ class TimetableCalendarViewState extends State<TimetableCalendarView> {
       GlobalKey<CustomWorkWeekCalendarState>();
 
   List<Appointment>? _cachedAppointments;
-  // TimetableSettings and List define no `==`, so record equality degrades to
-  // the same identity checks the cache always used.
-  (int, TimetableSettings, List<CustomTimetableEvent>, bool)? _cacheKey;
+  // Settings are keyed by the values the factory reads: the settings object is
+  // re-created on every settings write, so its identity would miss the cache
+  // for unrelated changes. The event list has no `==` and compares by identity.
+  (int, bool, TimetableNameMode, List<CustomTimetableEvent>, bool)? _cacheKey;
 
   // Stable identities let the calendar reuse its per-week pages across
   // rebuilds; rebuilding these every frame would invalidate that cache.
@@ -71,13 +72,16 @@ class TimetableCalendarViewState extends State<TimetableCalendarView> {
   }
 
   List<Appointment> _appointments(TimetableState state) {
-    final timetableSettings = context
-        .watch<SettingsCubit>()
-        .val()
-        .timetableSettings;
+    final (connectDoubleLessons, nameMode) = context.select(
+      (SettingsCubit c) => (
+        c.state.timetableSettings.connectDoubleLessons,
+        c.state.timetableSettings.timetableNameMode,
+      ),
+    );
     final key = (
       state.dataVersion,
-      timetableSettings,
+      connectDoubleLessons,
+      nameMode,
       widget.customEvents,
       widget.showClassInsteadOfTeacher,
     );
@@ -91,7 +95,7 @@ class TimetableCalendarViewState extends State<TimetableCalendarView> {
       customEvents: widget.customEvents,
       subjects: state.subjects?.result ?? const [],
       holidays: state.schoolHolidays?.result ?? const [],
-      settings: timetableSettings,
+      settings: context.read<SettingsCubit>().val().timetableSettings,
       now: DateTime.now(),
       showClassInsteadOfTeacher: widget.showClassInsteadOfTeacher,
     ).build();