gistfile1.txt

    private List<MainUiModel> sortAndFilterMeetings(
        @Nullable List<Meeting> meetings,
        @Nullable Map<Room, Boolean> selectedRooms
    ) {
        List<MainUiModel> result = new ArrayList<>();

        if (meetings == null || selectedRooms == null) {
            return result;
        }

        for (Meeting meeting : meetings) {
            boolean atLeastOneRoomIsSelected = false;

            for (Map.Entry<Room, Boolean> entry : selectedRooms.entrySet()) {
                Room room = entry.getKey();
                boolean isRoomSelected = entry.getValue() != null && entry.getValue();

                if (isRoomSelected) {
                    atLeastOneRoomIsSelected = true;
                }

                if (room == meeting.getRoom() && isRoomSelected) {
                    result.add(map(meeting));
                }
            }

            if (!atLeastOneRoomIsSelected) {
                result.add(map(meeting));
            }
        }

        return result;
    }