build method

@override Widget build(BuildContext context, WidgetRef ref)

Describes the part of the user interface represented by this widget.

The framework calls this method when this widget is inserted into the tree in a given BuildContext and when the dependencies of this widget change (e.g., an InheritedWidget referenced by this widget changes). This method can potentially be called in every frame and should not have any side effects beyond building a widget.

The framework replaces the subtree below this widget with the widget returned by this method, either by updating the existing subtree or by removing the subtree and inflating a new subtree, depending on whether the widget returned by this method can update the root of the existing subtree, as determined by calling Widget.canUpdate.

Typically implementations return a newly created constellation of widgets that are configured with information from this widget's constructor and from the given BuildContext.

The given BuildContext contains information about the location in the tree at which this widget is being built. For example, the context provides the set of inherited widgets for this location in the tree. A given widget might be built with multiple different BuildContext arguments over time if the widget is moved around the tree or if the widget is inserted into the tree in multiple places at once.

The implementation of this method must only depend on:

• the fields of the widget, which themselves must not change over time, and
• any ambient state obtained from the context using BuildContext.dependOnInheritedWidgetOfExactType.

If a widget's build method is to depend on anything else, use a StatefulWidget instead.

See also:

• StatelessWidget, which contains the discussion on performance considerations.

Implementation

@override
Widget build(BuildContext context, WidgetRef ref) {
  final calendarFormat = ref.watch(calendarFormatControllerProvider);
  // ignore: no_leading_underscores_for_local_identifiers
  final _focusedDay = ref.watch(focusedDayControllerProvider);

  /// Select Day(s) - Get Reservations on Selected Day(s)
  final selectedDays =
      ref.watch(selectedDaysControllerProvider); // LinkedHashSet<DateTime>
  // ReservationList, in terms of DateTime
  final reservations = useState<LinkedHashMap<DateTime, List<Reservation>>>(
      LinkedHashMap<DateTime, List<Reservation>>(
    equals: isSameDay,
    hashCode: getHashCode,
  ));

  final reservationList = ref.watch(reservationControllerProvider<T>());

  reservationList.when(data: (reservationList) {
    for (var reservation in reservationList) {
      for (var reservedDateTime in reservation.reservedDateTimes) {
        if (reservations.value.containsKey(reservedDateTime)) {
          reservations.value[reservedDateTime]!.add(reservation);
        } else {
          reservations.value[reservedDateTime] = [reservation];
        }
      }
    }
  }, loading: () {
    debugPrint("[[Loading]]: Loading...");
  }, error: (error, stackTrace) {
    debugPrint("[[Error]]: $error");
    debugPrint("[[StackTrace]]: $stackTrace");
  });

  final selectedReservations =
      // ref.watch(selectedReservationsControllerProvider);
      ref.watch(selectedItemsControllerProvider<Reservation>());

  final rangeSelectionMode = ref.watch(rangeSelectionModeControllerProvider);

  final rangeStart = ref.watch(rangeStartControllerProvider);
  debugPrint("[[Range Start]]: $rangeStart");
  final rangeEnd = ref.watch(rangeEndControllerProvider);
  debugPrint("[[Range End]]: $rangeEnd");

  // useEffect(() {
  //   _selectedDays.add(_focusedDay);
  //   debugPrint("[[called?]]: ${_selectedDays.contains(_focusedDay)}");
  //   return null;
  // }, []);

  List<Reservation> getReservationsForDay(DateTime day) {
    var reservationsForDay = reservations.value[day] ?? [];
    return reservationsForDay;
  }

  List<Reservation> getReservationsForDays(Iterable<DateTime> days) {
    var reservationsForDays = [
      for (final day in days) ...getReservationsForDay(day)
    ];
    return reservationsForDays;
  }

  List<Reservation> getReservationsForRange(DateTime start, DateTime end) {
    final days = daysInRange(start, end);
    var reservationsForRange = getReservationsForDays(days);
    return reservationsForRange;
  }

  void onDaySelected(DateTime selectedDay, DateTime focusedDay) {
    // if (!isSameDay(_selectedDay, selectedDay)) {

    /// [_selectedDays]: Update selected day
    ref.read(selectedDaysControllerProvider.notifier).toggle(selectedDay);
    ref.read(focusedDayControllerProvider.notifier).update(focusedDay);
    ref.read(rangeStartControllerProvider.notifier).update(null);
    ref.read(rangeEndControllerProvider.notifier).update(null);
    ref.read(rangeSelectionModeControllerProvider.notifier).toggleOff();
    // }

    ref
        .read(selectedReservationsControllerProvider<T>().notifier)
        // .read(selectedItemsControllerProvider<Reservation>().notifier)
        .onSelected(getReservationsForDays(selectedDays));
  }

  void onRangeSelected(DateTime? start, DateTime? end, DateTime focusedDay) {
    ref.read(focusedDayControllerProvider.notifier).update(focusedDay);

    // Enable range selection mode
    ref.read(rangeSelectionModeControllerProvider.notifier).toggleOn();

    // // Update range start and end
    ref.read(rangeStartControllerProvider.notifier).update(start);
    ref.read(rangeEndControllerProvider.notifier).update(end);

    // // Clear single-day selections
    ref.read(selectedDaysControllerProvider.notifier).clear();

    // // Debugging range values
    debugPrint("[[Range Start]]: $start");
    debugPrint("[[Range End]]: $end");

    // // Update selected reservations
    if (start != null && end != null) {
      ref
          .read(selectedReservationsControllerProvider().notifier)
          // .read(selectedItemsControllerProvider<Reservation>().notifier)
          .onSelected(getReservationsForRange(start, end));
    }
    // } else if (start != null) {
    //   ref
    //       .read(selectedReservationsControllerProvider.notifier)
    //       .update(_getReservationsForDay(start));
    // } else if (end != null) {
    //   ref
    //       .read(selectedReservationsControllerProvider.notifier)
    //       .update(_getReservationsForDay(end));
    // }
  }

  return TableCalendar<Reservation>(
    firstDay: kFirstDay,
    lastDay: kLastDay,
    focusedDay: _focusedDay,
    calendarFormat: calendarFormat,
    eventLoader: (day) {
      return getReservationsForDay(day);
    },
    selectedDayPredicate: (day) {
      // Use `selectedDayPredicate` to determine which day is currently selected.
      // If this returns true, then `day` will be marked as selected.
      // Using `isSameDay` is recommended to disregard
      // the time-part of compared DateTime objects.
      // return isSameDay(_selectedDay, day);
      // final selectedDays = ref.read(selectedDaysControllerProvider);
      return selectedDays.contains(day);
    },
    rangeStartDay: rangeStart,
    rangeEndDay: rangeEnd,
    rangeSelectionMode: rangeSelectionMode,
    onDaySelected: onDaySelected,
    // onDayLongPressed: (selectedDay, focusedDay) {
    //   ref.read(rangeSelectionModeControllerProvider.notifier).toggleOn();
    //   ref.read(rangeStartControllerProvider.notifier).update(selectedDay);
    //   ref.read(focusedDayControllerProvider.notifier).update(focusedDay);
    // },
    onRangeSelected: onRangeSelected,
    onFormatChanged: (format) {
      ref.read(calendarFormatControllerProvider.notifier).toggle();
    },
    onPageChanged: (focusedDay) {
      ref.read(focusedDayControllerProvider.notifier).update(focusedDay);
      debugPrint("[[FocusedDay]]: $focusedDay");
    },
  );
}