public function checkSync()
    {
        $content = $this->vbot->http->get($this->vbot->config['server.uri.push'].'/synccheck', ['timeout' => 35, 'query' => [
            'r'        => time(),
            'sid'      => $this->vbot->config['server.sid'],
            'uin'      => $this->vbot->config['server.uin'],
            'skey'     => $this->vbot->config['server.skey'],
            'deviceid' => $this->vbot->config['server.deviceId'],
            'synckey'  => $this->vbot->config['server.syncKeyStr'],
            '_'        => time(),
        ]]);

        if (!$content) {
            $this->vbot->console->log('checkSync no response');

            return false;
        }

        return preg_match('/window.synccheck=\{retcode:"(\d+)",selector:"(\d+)"\}/', $content, $matches) ?
            [$matches[1], $matches[2]] : false;
    }