react-use/src/useMultiStateValidator.ts

import { useCallback, useEffect, useRef, useState } from 'react';
import { StateValidator, UseStateValidatorReturn, ValidityState } from './useStateValidator';

export type MultiStateValidatorStates = any[] | { [p: string]: any } | { [p: number]: any };
export type MultiStateValidator<V extends ValidityState, S extends MultiStateValidatorStates> = StateValidator<V, S>;

export function useMultiStateValidator<V extends ValidityState, S extends MultiStateValidatorStates, I extends V>(
  states: S,
  validator: MultiStateValidator<V, S>,
  initialValidity: I = [undefined] as I
): UseStateValidatorReturn<V> {
  if (typeof states !== 'object') {
    throw new Error('states expected to be an object or array, got ' + typeof states);
  }

  const validatorInner = useRef(validator);
  const statesInner = useRef(states);

  validatorInner.current = validator;
  statesInner.current = states;

  const [validity, setValidity] = useState(initialValidity as V);

  const validate = useCallback(() => {
    if (validatorInner.current.length >= 2) {
      validatorInner.current(statesInner.current, setValidity);
    } else {
      setValidity(validatorInner.current(statesInner.current));
    }
  }, [setValidity]);

  useEffect(() => {
    validate();
  }, Object.values(states));

  return [validity, validate];
}