I am using react-multi-date-picker to create an exemptions scheduler. The react-multi-date-picker is used inside of a react-table as follows:

const [data, setData] = useState(0);
const [dateValues, setDateValues] = useState({});

const columns = useMemo(
  () => [
    {
      Header: "Exemptions",
      // First group columns
      columns: [
        {
          Header: "Exemptions",
          accessor: "exemptions",
          Cell: ({ row, data }) => (
            <DatePicker
              multiple
              key={data[row.index].id}
              onChange={(dateValues) => {
                const valueId = data[row.index].id;
                Object.keys(dateValues).map((key) => {
                  setDateValues((oldArray) => ({
                    ...oldArray,
                    [valueId]: {
                      ...oldArray[valueId],
                      [key]: dateValues[key]
                        ?.toDate?.()
                        .toISOString?.()
                        .substring?.(0, 10),
                    },
                  }));
                });
              }}
              plugins={[<DatePanel />]}
            />
          ),
        },
      ],
    },
  ],
  []
);

data produces an object from an axios call with the following structure.

(1) [{…}]
0:
  exemptions: null
  id: 1
  name: "John Smith"
  user_supervisor: "Joe Black"
  [[Prototype]]: Object

If I were to select 4 dates from the react-multi-date-picker and after my onChange call in the memoization hook, I am left with this in the dateValues:

{1: {…}}
1:
  0: "2022-02-02"
  1: "2022-02-03"
  2: "2022-02-08"
  3: "2022-02-08"
  [[Prototype]]: Object
[[Prototype]]: Object

This all works as expected. What I am struggling with is removing dates from the dateValues object when a user deselects the date from the react-multi-date-picker. I have tried using a ternary, I have tried using .filter and .includes. Every option I have tried throws a different error.

I am at a mental block on the logic needed. My thoughts have been I need to compare the previous state with the new state and keep matching values while discarding any values that don't match between the two states. I just can't code it in a way that works. Any help on this would be much appreciated.