/**
 * lodash 3.0.0 (Custom Build) <https://lodash.com/>
 * Build: `lodash modern modularize exports="npm" -o ./`
 * Copyright 2012-2015 The Dojo Foundation <http://dojofoundation.org/>
 * Based on Underscore.js 1.7.0 <http://underscorejs.org/LICENSE>
 * Copyright 2009-2015 Jeremy Ashkenas, DocumentCloud and Investigative Reporters & Editors
 * Available under MIT license <https://lodash.com/license>
 */
var isArguments = require('lodash.isarguments'),
    isArray = require('lodash.isarray'),
    isFunction = require('lodash.isfunction'),
    isString = require('lodash.isstring'),
    keys = require('lodash.keys');

/**
 * Checks if `value` is object-like.
 *
 * @private
 * @param {*} value The value to check.
 * @returns {boolean} Returns `true` if `value` is object-like, else `false`.
 */
function isObjectLike(value) {
  return (value && typeof value == 'object') || false;
}

/**
 * Used as the maximum length of an array-like value.
 * See the [ES spec](https://people.mozilla.org/~jorendorff/es6-draft.html#sec-number.max_safe_integer)
 * for more details.
 */
var MAX_SAFE_INTEGER = Math.pow(2, 53) - 1;

/**
 * Checks if `value` is a valid array-like length.
 *
 * **Note:** This function is based on ES `ToLength`. See the
 * [ES spec](https://people.mozilla.org/~jorendorff/es6-draft.html#sec-tolength)
 * for more details.
 *
 * @private
 * @param {*} value The value to check.
 * @returns {boolean} Returns `true` if `value` is a valid length, else `false`.
 */
function isLength(value) {
  return typeof value == 'number' && value > -1 && value % 1 == 0 && value <= MAX_SAFE_INTEGER;
}

/**
 * Checks if `value` is empty. A value is considered empty unless it is an
 * `arguments` object, array, string, or jQuery-like collection with a length
 * greater than `0` or an object with own enumerable properties.
 *
 * @static
 * @memberOf _
 * @category Lang
 * @param {Array|Object|string} value The value to inspect.
 * @returns {boolean} Returns `true` if `value` is empty, else `false`.
 * @example
 *
 * _.isEmpty(null);
 * // => true
 *
 * _.isEmpty(true);
 * // => true
 *
 * _.isEmpty(1);
 * // => true
 *
 * _.isEmpty([1, 2, 3]);
 * // => false
 *
 * _.isEmpty({ 'a': 1 });
 * // => false
 */
function isEmpty(value) {
  if (value == null) {
    return true;
  }
  var length = value.length;
  if (isLength(length) && (isArray(value) || isString(value) || isArguments(value) ||
      (isObjectLike(value) && isFunction(value.splice)))) {
    return !length;
  }
  return !keys(value).length;
}

module.exports = isEmpty;