JavaScript HTTP request thing

http.js

var http = {
    xhr: function () {
        if (typeof XMLHttpRequest !== 'undefined') {
            return new XMLHttpRequest();
        }

        var versions = [
            "MSXML2.XmlHttp.6.0",
            "MSXML2.XmlHttp.5.0",
            "MSXML2.XmlHttp.4.0",
            "MSXML2.XmlHttp.3.0",
            "MSXML2.XmlHttp.2.0",
            "Microsoft.XmlHttp"
        ];

        var xhr;
        for (var i = 0; i < versions.length; i++) {
            try {
                xhr = new ActiveXObject(versions[i]);
                break;
            } catch (e) { }
        }

        return xhr;
    },
    send: function (url, method, data) {
        var that = this;
        return new Promise((resolve, reject) => {
            var x = that.xhr();
            x.open(method, url);
            x.onreadystatechange = function () {
                if (x.readyState == 4) {
                    var data = x.responseText;
                    try {
                        data = JSON.parse(x.responseText);
                    } catch (e) {
                        // Skip and just use raw text
                    }

                    resolve(data);
                }
            };

            if (method == 'POST') {
                x.setRequestHeader('Content-type', 'application/x-www-form-urlencoded');
            }

            x.send(data)
        });
    },
    request: function (url, data, type) {
        var query = [];
        for (var key in data) {
            if (data.hasOwnProperty(key)) {
                query.push(encodeURIComponent(key) + "=" + encodeURIComponent(data[key]));
            }
        }

        if ($js.online && $js.online.user && $js.online.user.account) {
            query.push(encodeURIComponent("accessToken") + "=" + encodeURIComponent($js.online.user.account.accessToken));

            if ($js.online.player.id) {
                query.push(encodeURIComponent("player") + "=" + encodeURIComponent($js.online.player.id));
            }
        }

        if (type == "GET") {
            if (url.indexOf("?") >= 0) {
                url += (query.length ? "&" + query.join("&") : "");
            } else {
                url += (query.length ? "?" + query.join("&") : "");
            }
        }

        return this.send(url, type, query.join('&'));
    },
    get: function (url, data) {
        return this.request(url, data, "GET");
    },
    post: function (url, data) {
        return this.request(url, data, "POST");
    },
    put: function (url, data) {
        return this.request(url, data, "PUT");
    },
    delete: function (url, data) {
        return this.request(url, data, "DELETE");
    }
};