public function redirectToPaypal()
    {
        $parameters = Request::getRequestArrayFromString($request = null);
        foreach ($parameters as $name => $param) {
            if ($name == 'idSite'
                || $name == 'module'
                || $name == 'action'
            ) {
                unset($parameters[$name]);
            }
        }
        $paypalParameters = [
            "cmd" => "_s-xclick"
        ];
        if (empty($parameters["onetime"]) || $parameters["onetime"] != "true") {
            $paypalParameters["hosted_button_id"] = "DVKLY73RS7JTE";
            $paypalParameters["currency_code"] = "USD";
            $paypalParameters["on0"] = "Piwik Supporter";
            if (!empty($parameters["os0"])) {
                $paypalParameters["os0"] = $parameters["os0"];
            }
        } else {
            $paypalParameters["hosted_button_id"] = "RPL23NJURMTFA";
        }

        $url = "https://www.paypal.com/cgi-bin/webscr?" . Url::getQueryStringFromParameters($paypalParameters);

        Url::redirectToUrl($url);
        exit;
    }