var is = require('../lang/is');
var isArray = require('../lang/isArray');
var every = require('./every');

    /**
     * Compares if both arrays have the same elements
     */
    function equals(a, b, callback){
        callback = callback || is;

        if (!isArray(a) || !isArray(b)) {
            return callback(a, b);
        }

        if (a.length !== b.length) {
            return false;
        }

        return every(a, makeCompare(callback), b);
    }

    function makeCompare(callback) {
        return function(value, i) {
            return i in this && callback(value, this[i]);
        };
    }

    module.exports = equals;