group method

Implementation

Map<Weekday, Map<(SlotTimeUnit, SlotTimeUnit), List<Slot>>> group() {
  if (!state.hasData) {
    return {};
  }

  final grouped = <Weekday, SplayTreeMap<(SlotTimeUnit, SlotTimeUnit), List<Slot>>>{};

  for (final slot in state.requireData) {
    grouped[slot.weekday] ??= SplayTreeMap((a, b) {
      if (a.$1 == b.$1) {
        return a.$2.compareTo(b.$2);
      }

      return a.$1.compareTo(b.$1);
    });

    final timeGroup = (slot.startUnit, slot.endUnit);

    grouped[slot.weekday]![timeGroup] ??= [];

    grouped[slot.weekday]![timeGroup]!.add(slot);
  }

  return grouped;
}