bid/module/Listings/view/partials/voucher-code.phtml

<?php
/**
 * @version 7.9 [rev.7.9.01]
 */

$userId = (!empty($userId)) ? $userId : null;
$listingId = (!empty($listingId)) ? $listingId : null;

$voucherCode = (!empty($voucherCode)) ? $voucherCode : $this->request()->getRequest()->getParam('voucher_code');

$voucher = null;
if ($voucherCode) {
    $vouchersService = new \Ppb\Service\Vouchers();
    $voucher = $vouchersService->findBy($voucherCode, $userId);
}
?>
<div class="form-group">
    <div class="input-group">
        <?php echo $this->formElement('text', 'voucher_code')
            ->setValue($voucherCode)
            ->setAttributes(array(
                'class'       => 'form-control',
                'placeholder' => $this->_('Voucher Code'),
            ))
            ->render();
        ?>

        <span class="input-group-btn">
            <?php echo $this->formElement('submit', 'voucher_add', $this->_('Apply'))
                ->setAttributes(array(
                    'class' => 'btn btn-primary',
                ))
                ->render();
            ?>
        </span>
    </div>
    <div>
        <?php
        $valid = true;
        if ($voucher instanceof \Ppb\Db\Table\Row\Voucher) {
            if ($voucher->isValid($listingId)) {
                ?>
                <span class="label label-voucher label-success">
                    <?php echo sprintf(
                        $this->_('The voucher is valid. %s reduction applied'),
                        (($voucher['reduction_type'] == 'percent') ?
                            \Cube\Locale\Format::getInstance()->numericToLocalized($voucher['reduction_amount']) . '%' :
                            $this->amount($voucher['reduction_amount']))); ?>
                </span>
                <?php
            }
            else {
                $valid = false;
            }
        }

        if ($voucherCode && !$valid) {
            ?>
            <span class="label label-voucher label-danger">
                <?php echo $this->_('The voucher is not valid.'); ?>
            </span>
            <?php
        }
        else {
            ?>
            <span class="help-block">
                <?php echo $this->_('Enter your voucher code (if applicable) then click apply.'); ?>
            </span>
        <?php } ?>
    </div>
</div>