protected function __construct()
 {
     parent::__construct();
     // Cache CC info into hidden field
     add_filter('si_credit_card_form_controls', array($this, 'credit_card_cache'), 10, 2);
     add_action('si_checkout_action', array($this, 'process_credit_card_cache'), 10, 2);
     // Add CC input fields and process & validate
     add_action('si_checkout_action_' . SI_Checkouts::PAYMENT_PAGE, array($this, 'process_payment_page'), 10, 1);
 }
 protected function __construct()
 {
     parent::__construct();
     add_action('si_checkout_action_' . SI_Checkouts::PAYMENT_PAGE, array($this, 'processed_payment_page'), 20, 1);
 }