Change status of a transaction

<?php
//the PapApi.class.php can be downloaded from the merchant panel of Post Affiliate Pro
//at Start --> Tools > Integration > API Integration > Download PAP API

include 'PapApi.class.php'; 

//----------------------------------------------
// login (as merchant)
$session = new Pap_Api_Session("URL_to_PAP/scripts/server.php");

if(!$session->login("merchant@example.com","merchant_password")) {
    die("Cannot login. Message: ".$session->getMessage());
}
//----------------------------------------------
// loading a transaction with exact id e.g.:  e367f77a
$sale = new Pap_Api_Transaction($session);

$sale->setTransId('e367f77a');

if (!($sale->load())) { //loads the record with the given transaction id.
    die ("Loading of transaction failed!".$sale->getMessage());
}
//----------------------------------------------
// reading the status of a transaction
$status = $sale->getStatus();
echo "Getting status: " . $status;

//----------------------------------------------
// changing the status of a transaction
if ($status == 'P') { //if the status of the current transaction is Pending ('P' = pending; 'A' = Approved,  'D' = Declined)
	//then change its status to Approved. (If you change the 'A' for 'D' then it will change the status of the transaction to Declined)
    $sale->setStatus('A');
    $sale->setMerchantNote('transaction verified'); //merchant note can be viewed by both merchant and affiliate
}
$sale->save();
echo "Status of the transaction has been changed.";
?>