PayPal - Adaptive parallel Payments

<?php
class PaypalTest {

public $api_user = "XXXXXXXXXXXXXXXXXXXXXXXXXXX";
public $api_pass = "XXXXXXXXXXXXXXXXXXXX";
public $api_sig = "XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX";
public $app_id = "APP-80W284485P519543T";
public $apiUrl = 'https://svcs.sandbox.paypal.com/AdaptivePayments/';
//public $paypalUrl="https://www.paypal.com/webscr?cmd=_ap-payment&paykey=";
public $paypalUrl="https://sandbox.paypal.com/webscr?cmd=_ap-payment&paykey=";
public $headers;

public function __construct(){
    $this->headers = array(
        "X-PAYPAL-SECURITY-USERID: ".$this->api_user,
        "X-PAYPAL-SECURITY-PASSWORD: ".$this->api_pass,
        "X-PAYPAL-SECURITY-SIGNATURE: ".$this->api_sig,
        "X-PAYPAL-REQUEST-DATA-FORMAT: JSON",
        "X-PAYPAL-RESPONSE-DATA-FORMAT: JSON",
        "X-PAYPAL-APPLICATION-ID: ".$this->app_id,
    );
    $this->envelope= array(
            "errorLanguage" => "en_US",
            "detailLevel" => "ReturnAll",
        );
}

public function getPaymentOptions($paykey){

   $packet = array(
          "requestEnvelope" => $this->envelope ,
          "payKey" => $paykey
   );
  
   return $this->_paypalSend( $packet ,'GetPaymentOptions');
}

public function _paypalSend($data,$call){
    $ch = curl_init();
    curl_setopt($ch, CURLOPT_URL, $this->apiUrl.$call);
    curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
    curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, false);
    curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, false);
    curl_setopt($ch, CURLOPT_POSTFIELDS, json_encode($data));
    curl_setopt($ch, CURLOPT_HTTPHEADER, $this->headers);
    $response = json_decode(curl_exec($ch),true);
    return $response;

}
public function splitPay(){
    // create the pay request
    $createPacket = array(
        "actionType" =>"PAY",
        "currencyCode" => "USD",
        "receiverList" => array(
            "receiver" => array(
               array(
                    "amount"=> "2.00",
                    "email"=>"First Reciever Email"
                ),
                array(
                    "amount"=> "2.00",
                    "email"=>"Second Reciever Email"
                ),
            ),
        ),
        "returnUrl" => "http://your-site/confirm.php",
        "cancelUrl" => "http://your-site/cancel.php",
        "requestEnvelope" => $this->envelope
    );

    $response = $this->_paypalSend($createPacket,"Pay");
    $paykey =  $response['payKey'];
    //SET payment details
   
     $detailsPacket=array(
"requestEnvelope" =>$this->envelope,
"payKey" => $paykey,
"receiverOptions" => array(
    array(
    "receiver" => array("email" => "First Reciever Email"),
            "invoiceData" => array(
                "item" => array(
                    array(
                        "name" => "product1",
                        "price" => "2.00",
                        "identifier" => "p1"
                    ),
                   )
            )
    ),
    array(
        "receiver" => array("email" => 'Second Reciever Email'),
        "invoiceData" => array(
        "item" => array(
            array(
                "name" => "product1",
                "price" => "2.00",
                "identifier" => "p1"
            ),
        )
      )
    ),
)
);


    $response = $this->_paypalSend($detailsPacket,"SetPaymentOptions");
    $dets= $this->getPaymentOptions($paykey);
   
   
      header("Location: ".$this->paypalUrl.$paykey);
}
}


$payment = new PaypalTest();
$payment->splitPay();

?>