protected function getPurchaseParams()
    {
        $url = "checkout/complete/{$this->data_order['order_id']}";

        return array(
            'currency' => $this->data_order['currency'],
            'amount' => $this->data_order['total_formatted_number'],
            'returnUrl' => $this->controller->url($url, array('authorize_return' => true), true),
            'cancelUrl' => $this->controller->url($url, array('authorize_return' => true, 'cancel' => true), true)
        );
    }