functions.php

require_once('PagSeguroLibrary/PagSeguroLibrary.php');

function generate_pagseguro($user_id){
    
    // Instantiate a new payment request
    $paymentRequest = new PagSeguroPaymentRequest();

    // Set the currency
    $paymentRequest->setCurrency("BRL");

    // Add an item for this payment request
    $paymentRequest->addItem('0001', 'Anuidade', 1, 150.00);

    // Set a reference code for this payment request. It is useful to identify this payment
    // in future notifications.
    $paymentRequest->setReference("REF123");

    // Set shipping information for this payment request
    //$sedexCode = PagSeguroShippingType::getCodeByType('SEDEX');
    //$paymentRequest->setShippingType($sedexCode);
    /*$paymentRequest->setShippingAddress(
        '01452002',
        'Av. Brig. Faria Lima',
        '1384',
        'apto. 114',
        'Jardim Paulistano',
        'São Paulo',
        'SP',
        'BRA'
    );*/

    // Set your customer information.
    $paymentRequest->setSender(
        'João Comprador',
        'c10812467032782726659@sandbox.pagseguro.com.br',
        '11',
        '56273440',
        'CPF',
        '156.009.442-76'
    );

    // Set the url used by PagSeguro to redirect user after checkout process ends
    //$paymentRequest->setRedirectUrl("http://wordpress.local/pagseguro");

    // Add checkout metadata information
    //$paymentRequest->addMetadata('PASSENGER_CPF', '15600944276', 1);
    //$paymentRequest->addMetadata('GAME_NAME', 'DOTA');
    //$paymentRequest->addMetadata('PASSENGER_PASSPORT', '23456', 1);

    // Another way to set checkout parameters
    //$paymentRequest->addParameter('notificationURL', 'http://www.lojamodelo.com.br/nas');
    //$paymentRequest->addParameter('senderBornDate', '07/05/1981');
    //$paymentRequest->addIndexedParameter('itemId', '0003', 3);
    //$paymentRequest->addIndexedParameter('itemDescription', 'Notebook Preto', 3);
    //$paymentRequest->addIndexedParameter('itemQuantity', '1', 3);
    //$paymentRequest->addIndexedParameter('itemAmount', '200.00', 3);

    // Add installment without addition per payment method
    //$paymentRequest->addPaymentMethodConfig('CREDIT_CARD', 6, 'MAX_INSTALLMENTS_NO_INTEREST');

    // Add installment limit per payment method
    //$paymentRequest->addPaymentMethodConfig('CREDIT_CARD', 8, 'MAX_INSTALLMENTS_LIMIT');

    // Add and remove a group and payment methods
    //$paymentRequest->acceptPaymentMethodGroup('CREDIT_CARD', 'DEBITO_ITAU');      
    //$paymentRequest->excludePaymentMethodGroup('BOLETO', 'BOLETO');

    try {

        /*
         * #### Credentials #####
         * Replace the parameters below with your credentials
         * You can also get your credentials from a config file. See an example:
         * $credentials = new PagSeguroAccountCredentials("vendedor@lojamodelo.com.br",
         * "E231B2C9BCC8474DA2E260B6C8CF60D3");
         */

        // seller authentication
        $credentials = PagSeguroConfig::getAccountCredentials();

        // application authentication
        //$credentials = PagSeguroConfig::getApplicationCredentials();

        //$credentials->setAuthorizationCode("E231B2C9BCC8474DA2E260B6C8CF60D3");

        // Register this payment request in PagSeguro to obtain the payment URL to redirect your customer.
        $url = $paymentRequest->register($credentials);

        add_user_meta( $user_id, 'pagseguro', $url, true );

        return $url;

    } catch (PagSeguroServiceException $e) {
        die($e->getMessage());
    }
}

add_action( 'user_register', 'register_pagseguro', 10, 1 );
function register_pagseguro( $user_id ) {
	$pagseguro_url = generate_pagseguro($user_id);
	wp_redirect( $pagseguro_url );
	exit;
}