import { isString } from '@rawmodel/utils/dist/helpers/is-string';
import { isUndefined } from '@rawmodel/utils/dist/helpers/is-undefined';
import { isNull } from '@rawmodel/utils/dist/helpers/is-null';

const ISO8601_REGEX = /^([\+-]?\d{4}(?!\d{2}\b))((-?)((0[1-9]|1[0-2])(\3([12]\d|0[1-9]|3[01]))?|W([0-4]\d|5[0-2])(-?[1-7])?|(00[1-9]|0[1-9]\d|[12]\d{2}|3([0-5]\d|6[1-6])))([T\s]((([01]\d|2[0-3])((:?)[0-5]\d)?|24:?00)([\.,]\d+(?!:))?)?(\17[0-5]\d([\.,]\d+)?)?([zZ]|([\+-])([01]\d|2[0-3]):?([0-5]\d)?)?)?)?$/;

/**
 * Returns a function for detecting date values.
 */
export function dateValidator(recipe: {
  iso?: boolean;
} = {}) {
  return (value?: any) => {

    if (isUndefined(value) || isNull(value)) {
      return true;
    }
    else if (!isString(value)) {
      return false;
    }

    const date = Date.parse(value);
    if (!date) return false;

    const { iso } = recipe;
    if (iso) {
      return ISO8601_REGEX.test(value);
    }

    return true;
  };
}