var $ = (function () {

    'use strict';

    /**
     * Create the constructor
     * @param {String} selector The selector to use
     */
    var Constructor = function (selector) {
        if (!selector) return;
        if (selector === 'document') {
            this.elems = [document];
        } else if (selector === 'window') {
            this.elems = [window];
        } else {
            this.elems = document.querySelectorAll(selector);
        }
    };

    /**
     * Do ajax stuff
     * @param  {String} url The URL to get
     */
    Constructor.prototype.ajax = function (url) {
        // Do some XHR/Fetch thing here
        console.log(url);
    };

    /**
     * Run a callback on each item
     * @param  {Function} callback The callback function to run
     */
    Constructor.prototype.each = function (callback) {
        if (!callback || typeof callback !== 'function') return;
        for (var i = 0; i < this.elems.length; i++) {
            callback(this.elems[i], i);
        }
        return this;
    };

    /**
     * Add a class to elements
     * @param {String} className The class name
     */
    Constructor.prototype.addClass = function (className) {
        this.each(function (item) {
            item.classList.add(className);
        });
        return this;
    };

    /**
     * Remove a class to elements
     * @param {String} className The class name
     */
    Constructor.prototype.removeClass = function (className) {
        this.each(function (item) {
            item.classList.remove(className);
        });
        return this;
    };

    /**
     * Instantiate a new constructor
     */
    var instantiate = function (selector) {
        return new Constructor(selector);
    };

    /**
     * Return the constructor instantiation
     */
    return instantiate;

})();