/**
 * lodash (Custom Build) <https://lodash.com/>
 * Build: `lodash modularize exports="npm" -o ./`
 * Copyright jQuery Foundation and other contributors <https://jquery.org/>
 * Released under MIT license <https://lodash.com/license>
 * Based on Underscore.js 1.8.3 <http://underscorejs.org/LICENSE>
 * Copyright Jeremy Ashkenas, DocumentCloud and Investigative Reporters & Editors
 */
var baseEachRight = require('lodash._baseeachright'),
    baseIteratee = require('lodash._baseiteratee'),
    baseReduce = require('lodash._basereduce');

/**
 * A specialized version of `_.reduceRight` for arrays without support for
 * iteratee shorthands.
 *
 * @private
 * @param {Array} array The array to iterate over.
 * @param {Function} iteratee The function invoked per iteration.
 * @param {*} [accumulator] The initial value.
 * @param {boolean} [initAccum] Specify using the last element of `array` as
 *  the initial value.
 * @returns {*} Returns the accumulated value.
 */
function arrayReduceRight(array, iteratee, accumulator, initAccum) {
  var length = array.length;
  if (initAccum && length) {
    accumulator = array[--length];
  }
  while (length--) {
    accumulator = iteratee(accumulator, array[length], length, array);
  }
  return accumulator;
}

/**
 * This method is like `_.reduce` except that it iterates over elements of
 * `collection` from right to left.
 *
 * @static
 * @memberOf _
 * @since 0.1.0
 * @category Collection
 * @param {Array|Object} collection The collection to iterate over.
 * @param {Function} [iteratee=_.identity] The function invoked per iteration.
 * @param {*} [accumulator] The initial value.
 * @returns {*} Returns the accumulated value.
 * @see _.reduce
 * @example
 *
 * var array = [[0, 1], [2, 3], [4, 5]];
 *
 * _.reduceRight(array, function(flattened, other) {
 *   return flattened.concat(other);
 * }, []);
 * // => [4, 5, 2, 3, 0, 1]
 */
function reduceRight(collection, iteratee, accumulator) {
  var func = isArray(collection) ? arrayReduceRight : baseReduce,
      initAccum = arguments.length < 3;

  return func(collection, baseIteratee(iteratee, 4), accumulator, initAccum, baseEachRight);
}

/**
 * Checks if `value` is classified as an `Array` object.
 *
 * @static
 * @memberOf _
 * @since 0.1.0
 * @type {Function}
 * @category Lang
 * @param {*} value The value to check.
 * @returns {boolean} Returns `true` if `value` is correctly classified,
 *  else `false`.
 * @example
 *
 * _.isArray([1, 2, 3]);
 * // => true
 *
 * _.isArray(document.body.children);
 * // => false
 *
 * _.isArray('abc');
 * // => false
 *
 * _.isArray(_.noop);
 * // => false
 */
var isArray = Array.isArray;

module.exports = reduceRight;