Open next week once there are no more school days for this week anymore (#2131)

Closes #1702

Author: nilsreichardt

app/lib/navigation/models/navigation_item.dart

@@ -192,7 +192,7 @@ extension NavigationItemExtension on NavigationItem {
       case NavigationItem.homework:
         return const HomeworkPage();
       case NavigationItem.timetable:
-        return TimetablePage();
+        return const TimetablePage();
       case NavigationItem.blackboard:
         return const BlackboardPage();
       case NavigationItem.grades:

app/lib/settings/src/subpages/timetable/timetable_settings_page.dart

@@ -58,6 +58,8 @@ class TimetableSettingsPage extends StatelessWidget {
                   const Divider(),
                   _TimetableEnabledWeekDaysField(),
                   const Divider(),
+                  _OpenUpcomingWeekOnNonSchoolDays(),
+                  const Divider(),
                   const _ICalLinks(),
                   // We only show the time picker settings on iOS because on
                   // other platforms we use the different time picker where we
@@ -240,6 +242,38 @@ class _TimetableEnabledWeekDaysField extends StatelessWidget {
   }
 }
 
+class _OpenUpcomingWeekOnNonSchoolDays extends StatelessWidget {
+  @override
+  Widget build(BuildContext context) {
+    final bloc = BlocProvider.of<UserSettingsBloc>(context);
+    return StreamBuilder<UserSettings>(
+      stream: bloc.streamUserSettings(),
+      builder: (context, snapshot) {
+        if (!snapshot.hasData) return const SizedBox.shrink();
+        final userSettings = snapshot.data!;
+        return SwitchListTile.adaptive(
+          title: Text(
+            context.l10n.timetableSettingsOpenUpcomingWeekOnNonSchoolDaysTitle,
+          ),
+          subtitle: Text(
+            context
+                .l10n
+                .timetableSettingsOpenUpcomingWeekOnNonSchoolDaysSubtitle,
+          ),
+          value: userSettings.openUpcomingWeekOnNonSchoolDays,
+          onChanged: (newValue) {
+            bloc.updateSettings(
+              userSettings.copyWith(
+                openUpcomingWeekOnNonSchoolDays: newValue,
+              ),
+            );
+          },
+        );
+      },
+    );
+  }
+}
+
 class LessonsLengthField extends StatelessWidget {
   const LessonsLengthField({
     super.key,

app/lib/timetable/src/bloc/timetable_bloc.dart

@@ -310,6 +310,10 @@ class TimetableConfig {
     return _getUserSettings().showAbbreviation;
   }
 
+  bool openUpcomingWeekOnNonSchoolDays() {
+    return _getUserSettings().openUpcomingWeekOnNonSchoolDays;
+  }
+
   Time getTimetableStartTime() {
     return _getUserSettings().timetableStartTime;
   }

app/lib/timetable/src/logic/timetable_date_helper.dart

@@ -6,13 +6,15 @@
 //
 // SPDX-License-Identifier: EUPL-1.2
 
+import 'dart:math';
+
 import 'package:date/date.dart';
 import 'package:user/user.dart';
 
 class TimetableDateHelper {
-  static Date dateBeginThisWeek() {
-    Date today = Date.today();
-    Date startOfThisWeek = today.addDays(-(today.weekDay - 1));
+  static Date dateBeginThisWeek({Date? today}) {
+    final currentDate = today ?? Date.today();
+    Date startOfThisWeek = currentDate.addDays(-(currentDate.weekDay - 1));
     return startOfThisWeek;
   }
 
@@ -24,6 +26,28 @@ class TimetableDateHelper {
     return dateAddDays(date, weeks * 7);
   }
 
+  static bool shouldOpenUpcomingWeek({
+    required Date today,
+    required EnabledWeekDays enabledWeekDays,
+    required bool isFeatureEnabled,
+    required Iterable<Date> eventDatesInCurrentWeek,
+  }) {
+    if (!isFeatureEnabled) return false;
+    final enabledDays = enabledWeekDays.getEnabledWeekDaysList();
+    if (enabledDays.isEmpty) return false;
+    final lastEnabledIndex = enabledDays.map((day) => day.index).reduce(max);
+    if (today.weekDayEnum.index <= lastEnabledIndex) return false;
+    final hasUpcomingEventOnNonEnabledDay = eventDatesInCurrentWeek.any((
+      eventDate,
+    ) {
+      final isEnabledDay =
+          enabledWeekDays.getValue(eventDate.weekDayEnum) ?? false;
+      if (isEnabledDay) return false;
+      return !eventDate.isBefore(today);
+    });
+    return !hasUpcomingEventOnNonEnabledDay;
+  }
+
   // THERE ARE MORE OPTIMAL CALCULATION METHODES, BUT I LIKE THIS DESIGN :)
   static List<Date> generateDaysList(
     Date startDate,

app/lib/timetable/timetable_page/timetable_page.dart

@@ -6,9 +6,11 @@
 //
 // SPDX-License-Identifier: EUPL-1.2
 
+import 'dart:async';
 import 'dart:math';
 
 import 'package:bloc_provider/bloc_provider.dart';
+import 'package:date/date.dart';
 import 'package:flutter/cupertino.dart';
 import 'package:flutter/foundation.dart';
 import 'package:flutter/gestures.dart';
@@ -49,10 +51,9 @@ class TimetablePage extends StatelessWidget {
   static const tag = "timetable-page";
   static const days = 5;
 
-  final today = TimetableDateHelper.dateBeginThisWeek();
   static const timetableScale = 1.00;
 
-  TimetablePage({super.key});
+  const TimetablePage({super.key});
 
   String getAdUnitId(BuildContext context) {
     if (kDebugMode) {
@@ -143,8 +144,8 @@ class _SettingsIcon extends StatelessWidget {
   }
 }
 
-class TimeTableUnit extends StatelessWidget {
-  TimeTableUnit({
+class TimeTableUnit extends StatefulWidget {
+  const TimeTableUnit({
     super.key,
     required this.groupInfos,
     required this.lessons,
@@ -155,12 +156,60 @@ class TimeTableUnit extends StatelessWidget {
   final List<Lesson> lessons;
   final TimetableConfig timetableConfig;
 
-  final today = TimetableDateHelper.dateBeginThisWeek();
+  @override
+  State<TimeTableUnit> createState() => _TimeTableUnitState();
+}
+
+class _TimeTableUnitState extends State<TimeTableUnit> {
+  late final Date _today = Date.today();
+  late final Date _startOfCurrentWeek = TimetableDateHelper.dateBeginThisWeek(
+    today: _today,
+  );
+  late final Date _endOfCurrentWeek = TimetableDateHelper.dateAddDays(
+    _startOfCurrentWeek,
+    6,
+  );
+  final PageController _pageController = PageController();
+  late StreamSubscription<List<CalendricalEvent>>? _initialWeekSub;
+
+  void _maybeJumpToUpcomingWeek(Iterable<CalendricalEvent> events) {
+    final shouldOpenUpcomingWeek = TimetableDateHelper.shouldOpenUpcomingWeek(
+      today: _today,
+      enabledWeekDays: widget.timetableConfig.getEnabledWeekDays(),
+      isFeatureEnabled:
+          widget.timetableConfig.openUpcomingWeekOnNonSchoolDays(),
+      eventDatesInCurrentWeek: events.map((e) => e.date),
+    );
+
+    if (!shouldOpenUpcomingWeek || !mounted) return;
+    _pageController.jumpToPage(1);
+  }
 
   @override
-  Widget build(BuildContext context) {
-    final bloc = BlocProvider.of<TimetableBloc>(context);
+  void initState() {
+    super.initState();
+
+    WidgetsBinding.instance.addPostFrameCallback((_) {
+      if (!mounted) return;
 
+      final bloc = context.read<TimetableBloc>();
+      _initialWeekSub = bloc
+          .events(_startOfCurrentWeek, endDate: _endOfCurrentWeek)
+          .where((events) => events.isNotEmpty || true)
+          .take(1)
+          .listen(_maybeJumpToUpcomingWeek);
+    });
+  }
+
+  @override
+  void dispose() {
+    _initialWeekSub?.cancel();
+    _pageController.dispose();
+    super.dispose();
+  }
+
+  @override
+  Widget build(BuildContext context) {
     return PageView.builder(
       // Users expect to be able to drag the timetable horizontally to the
       // next/previous week via mouse as this is old behavior.
@@ -170,25 +219,31 @@ class TimeTableUnit extends StatelessWidget {
       // workaround to explicitly re-enable this behavior. See:
       // https://docs.flutter.dev/release/breaking-changes/default-scroll-behavior-drag
       //
-      // In the future we might add explicit buttons to go forward or backwards
-      // a week in the timetable - in this case desktop might remove this
-      // behavior.
+      // In the future we might add explicit buttons to go forward or
+      // backwards a week in the timetable - in this case desktop might
+      // remove this behavior.
       scrollBehavior: ScrollConfiguration.of(context).copyWith(
         dragDevices: {PointerDeviceKind.touch, PointerDeviceKind.mouse},
       ),
+      controller: _pageController,
       itemBuilder: (context, index) {
-        final startOfWeek = TimetableDateHelper.dateAddWeeks(today, index);
+        final startOfWeek = TimetableDateHelper.dateAddWeeks(
+          _startOfCurrentWeek,
+          index,
+        );
         final endDate = TimetableDateHelper.dateAddDays(startOfWeek, 6);
         final daysList = TimetableDateHelper.generateDaysList(
           startOfWeek,
           endDate,
-          timetableConfig.getEnabledWeekDays(),
+          widget.timetableConfig.getEnabledWeekDays(),
         );
 
         final filteredLessonsList = getFilteredLessonList(
-          lessons,
-          timetableConfig.getWeekType(daysList.first),
+          widget.lessons,
+          widget.timetableConfig.getWeekType(daysList.first),
         );
+
+        final bloc = BlocProvider.of<TimetableBloc>(context);
         return StreamBuilder<List<CalendricalEvent>>(
           stream: bloc.events(startOfWeek, endDate: endDate),
           builder: (context, snapshot) {
@@ -197,13 +252,13 @@ class TimeTableUnit extends StatelessWidget {
               filteredLessonsList,
               daysList,
               events,
-              groupInfos,
+              widget.groupInfos,
             );
             return TimetableWeekView(
               dates: daysList,
               elements: [...builder.buildElements()],
-              config: timetableConfig,
-              periods: timetableConfig.getPeriods(),
+              config: widget.timetableConfig,
+              periods: widget.timetableConfig.getPeriods(),
             );
           },
         );

app/test/timetable/timetable_date_helper_test.dart

@@ -0,0 +1,76 @@
+// Copyright (c) 2024 Sharezone UG (haftungsbeschränkt)
+// Licensed under the EUPL-1.2-or-later.
+//
+// You may obtain a copy of the Licence at:
+// https://joinup.ec.europa.eu/software/page/eupl
+//
+// SPDX-License-Identifier: EUPL-1.2
+
+import 'package:date/date.dart';
+import 'package:date/weekday.dart';
+import 'package:flutter_test/flutter_test.dart';
+import 'package:sharezone/timetable/src/logic/timetable_date_helper.dart';
+import 'package:user/user.dart';
+
+void main() {
+  group(TimetableDateHelper.shouldOpenUpcomingWeek, () {
+    test(
+      'opens upcoming week after last enabled weekday when feature is enabled',
+      () {
+        final today = Date.parse('2024-08-10'); // Saturday
+        final result = TimetableDateHelper.shouldOpenUpcomingWeek(
+          today: today,
+          enabledWeekDays: EnabledWeekDays.standard,
+          isFeatureEnabled: true,
+          eventDatesInCurrentWeek: <Date>[],
+        );
+
+        expect(result, isTrue);
+      },
+    );
+
+    test('does not open upcoming week when feature is disabled', () {
+      final today = Date.parse('2024-08-10'); // Saturday
+      final result = TimetableDateHelper.shouldOpenUpcomingWeek(
+        today: today,
+        enabledWeekDays: EnabledWeekDays.standard,
+        isFeatureEnabled: false,
+        eventDatesInCurrentWeek: <Date>[],
+      );
+
+      expect(result, isFalse);
+    });
+
+    test('does not open upcoming week when today is an enabled weekday', () {
+      final today = Date.parse('2024-08-10'); // Saturday
+      final enabledWeekDays = EnabledWeekDays.fromEnabledWeekDaysList([
+        WeekDay.monday,
+        WeekDay.tuesday,
+        WeekDay.wednesday,
+        WeekDay.thursday,
+        WeekDay.friday,
+        WeekDay.saturday,
+      ]);
+      final result = TimetableDateHelper.shouldOpenUpcomingWeek(
+        today: today,
+        enabledWeekDays: enabledWeekDays,
+        isFeatureEnabled: true,
+        eventDatesInCurrentWeek: <Date>[],
+      );
+
+      expect(result, isFalse);
+    });
+
+    test('does not open upcoming week when there is an upcoming event', () {
+      final today = Date.parse('2024-08-10'); // Saturday
+      final result = TimetableDateHelper.shouldOpenUpcomingWeek(
+        today: today,
+        enabledWeekDays: EnabledWeekDays.standard,
+        isFeatureEnabled: true,
+        eventDatesInCurrentWeek: [Date.parse('2024-08-10')],
+      );
+
+      expect(result, isFalse);
+    });
+  });
+}