Facade Design Pattern

function Facade(){
    
}
Facade.prototype.Select = function(s){
    if(s === undefined){return;}
    this.selector = s.trim();
    this.elem = document.getElementById(this.selector)
    console.log(this)
    return this;
}
Facade.prototype.removeClass = function(cls){
    var elem = this.elem;
    var RTN = " " + elem.getAttribute("class") + " ";
    if(elem.getAttribute("class") != "" && elem.getAttribute("class") !== null && elem.getAttribute("class") !== undefined){
        RTN = RTN.replace(new RegExp(" " + cls + " ", "g"),"");
        RTN = RTN.replace(/  /g, " ");
        this.elem.setAttribute("class", RTN.trim());
    }
    return elem.getAttribute("class");
}
Facade.prototype.addClass = function(cls){
    var elem = this.elem;
    var clss = "";
    if(elem.getAttribute("class") === null){
        clss = cls;
    }else{
        clss = elem.getAttribute("class").trim() + " " + cls;
    }
    elem.setAttribute("class", clss);
    return clss;
}
var facade = new Facade();
var $ = facade.Select.bind(facade);
/**
*   EXAMPLE 
*/
$("test").addClass("test");