stateOrder.ts

export const stateOrder = selectorFamily<IOrder, IRecoilId>({
  key: 'state-order',
  get: (familyKey) => ({ get }) => {
    const { color, size, productId, count } = get(
      waitForAll({
        productId: stateProductId(familyKey),
        color: stateColor(familyKey),
        size: stateSize(familyKey),
        count: stateCount(familyKey),
      })
    );
    return {id: familyKey.id, count, size, color, productId};
  },
  set: (familyKey) => ({ set, reset }, value) => {
    const { journey, id } = familyKey;
    // reset (when recoil's value is empty, will discuss later)
    if (guardRecoilDefaultValue(value)) {
      reset(stateProductId(familyKey));
      reset(stateColor(familyKey));
      reset(stateSize(familyKey));
      reset(stateCount(familyKey));
      // remove from tracking
      set(stateTracking(journey),
               (prv) => [...prv.filter((m) => m !== id)]);
      return;
    }
    // set
    set(stateProductId(familyKey), value.productId);
    set(stateColor(familyKey), value.color);
    set(stateSize(familyKey), value.size);
    set(stateCount(familyKey), value.count);
    // track
    set(stateTracking(journey), (prv) => {
      return [...prv, id];
    });
  }
});