/**
 * @fileoverview Utilities to operate on option objects.
 * @author Josh Goldberg
 */

'use strict';

/**
 * Determines whether any of input's properties are different
 * from values that already exist in original.
 * @template T
 * @param {Partial<T>} input New value.
 * @param {T} original Original value.
 * @returns {boolean} Whether input includes an explicit difference.
 */
function containsDifferentProperty(input, original) {
  if (input === original) {
    return false;
  }

  if (
    typeof input !== typeof original ||
    Array.isArray(input) !== Array.isArray(original)
  ) {
    return true;
  }

  if (Array.isArray(input)) {
    return (
      input.length !== original.length ||
      input.some((value, i) => containsDifferentProperty(value, original[i]))
    );
  }

  if (typeof input === 'object') {
    if (input === null || original === null) {
      return true;
    }

    const inputKeys = Object.keys(input);
    const originalKeys = Object.keys(original);

    return (
      inputKeys.length !== originalKeys.length ||
      inputKeys.some(
        (inputKey) =>
          !Object.hasOwn(original, inputKey) ||
          containsDifferentProperty(input[inputKey], original[inputKey])
      )
    );
  }

  return true;
}

module.exports = {
  containsDifferentProperty,
};