public function email_pay_now_button($order)
 {
     $type = $this->get_current_email_object();
     if ($type && $type->id == 'customer_processing_order') {
         WC_GZD_Checkout::instance()->add_payment_link($order->id);
     }
 }
 public static function instance()
 {
     if (is_null(self::$_instance)) {
         self::$_instance = new self();
     }
     return self::$_instance;
 }
 /**
  * Pay now button on success page
  */
 function woocommerce_gzd_template_order_pay_now_button($order_id)
 {
     WC_GZD_Checkout::instance()->add_payment_link($order_id);
 }