class Req {
    static post(url, data, callback) {
        const xhttp = new XMLHttpRequest();
        xhttp.open("POST",url,true);
        xhttp.onload = function(){
            if (this.readyState == 4 && this.status == 200) {
                callback(JSON.parse(xhttp.responseText));
            }
        }
        xhttp.onerror = function () {
            console.log("error")
        };
        xhttp.setRequestHeader("Content-type", "application/x-www-form-urlencoded");
        xhttp.send(data);
    }

    static postData(url, data, callback) {
        const xhttp = new XMLHttpRequest();
        xhttp.open("POST",url,true);
        xhttp.onload = function(){
            if (this.readyState == 4 && this.status == 200) {
                callback(xhttp.responseText);
            }
        }
        xhttp.onerror = function () {
            console.log("error")
        };
        xhttp.setRequestHeader("Content-type", "application/x-www-form-urlencoded");
        xhttp.send(data);
    }

    static get(url, callback) {
        const xhttp = new XMLHttpRequest();
        xhttp.onreadystatechange = function(){
            if (this.readyState == 4 && this.status == 200) {
                callback(JSON.parse(xhttp.responseText));
            }else{
                console.log("err")
            }
        }

        xhttp.open("GET",url,true);
        xhttp.send();
    }

    static ready(callback){
        document.addEventListener('DOMContentLoaded', callback);
    }
}