public function payDemo()
{
$this->authorize();
$addr = new Address();
$addr->setLine1('52 N Main ST');
$addr->setCity('Johnstown');
$addr->setCountryCode('US');
$addr->setPostalCode('43210');
$addr->setState('OH');
$card = new CreditCard();
$card->setNumber('4417119669820331');
$card->setType('visa');
$card->setExpireMonth('11');
$card->setExpireYear('2018');
$card->setCvv2('874');
$card->setFirstName('Joe');
$card->setLastName('Shopper');
$card->setBillingAddress($addr);
$fi = new FundingInstrument();
$fi->setCreditCard($card);
$payer = new Payer();
$payer->setPaymentMethod('credit_card');
$payer->setFundingInstruments(array($fi));
$amountDetails = new \PayPal\Api\Details();
$amountDetails->setSubtotal('7.41');
$amountDetails->setTax('0.03');
$amountDetails->setShipping('0.03');
$amount = new Amount();
$amount->setCurrency('USD');
$amount->setTotal('7.47');
$amount->setDetails($amountDetails);
$transaction = new Transaction();
$transaction->setAmount($amount);
$transaction->setDescription('This is the payment transaction description.');
$payment = new Payment();
$payment->setIntent('sale');
$payment->setPayer($payer);
$payment->setTransactions(array($transaction));
$payment->create($this->_apiContext);
}
$card->setType(strtolower($_SESSION['cc_type']));
$card->setExpireMonth($_SESSION['cc_exp_month']);
$card->setExpireYear($_SESSION['cc_exp_year']);
$card->setCvv2($_SESSION['cvv2']);
$card->setFirstName($_SESSION['billing_first_name']);
$card->setLastName($_SESSION['billing_last_name']);
$card->setBillingAddress($addr);
$fi = new \PayPal\Api\FundingInstrument();
$fi->setCreditCard($card);
$payer = new \PayPal\Api\Payer();
$payer->setPaymentMethod('credit_card');
$payer->setFundingInstruments(array($fi));
$amountDetails = new \PayPal\Api\Details();
$amountDetails->setSubtotal(str_replace(",", "", number_format($_SESSION['subtotal'], 2)));
$amountDetails->setTax(str_replace(",", "", number_format($_SESSION['tax_amount'], 2)));
$amountDetails->setShipping(str_replace(",", "", number_format($_SESSION['shipping_amount'], 2)));
$amountDetails->setHandlingFee(str_replace(",", "", number_format($_SESSION['handling_amount'], 2)));
$amount = new \PayPal\Api\Amount();
$amount->setCurrency(isset($config['CurrencyCode']) ? $config['CurrencyCode'] : 'USD');
$amount->setTotal(str_replace(",", "", number_format($_SESSION['amount'], 2)));
$amount->setDetails($amountDetails);
$transaction = new \PayPal\Api\Transaction();
$transaction->setAmount($amount);
$transaction->setDescription(isset($_SESSION['item_name']) && $_SESSION['item_name'] != '' ? $_SESSION['item_name'] : 'PayPal Payments Pro Virtual Terminal Sale');
$transaction->setInvoiceNumber($_SESSION['invoice']);
$transaction->setCustom($_SESSION['notes']);
$payment = new \PayPal\Api\Payment();
$payment->setIntent(strtolower($_SESSION['transaction_type']));
$payment->setPayer($payer);
$payment->setTransactions(array($transaction));
try {
