payment window fix

src/main/java/com/unicenta/pos/payment/PaymentGatewayPaymentSense.java

@@ -26,6 +26,7 @@ import lombok.extern.slf4j.Slf4j;
 
 import javax.swing.*;
 import java.awt.*;
+import java.util.ArrayList;
 
 @Slf4j
 public class PaymentGatewayPaymentSense implements PaymentGateway {
@@ -34,13 +35,26 @@ public class PaymentGatewayPaymentSense implements PaymentGateway {
     public PaymentGatewayPaymentSense() {
     }
 
-    Window getPaymentWindow() {
-        for (Window window : Window.getWindows()) {
-            if (window.isActive()) {
-                return window;
+    Window getPaymentWindow(double amount) {
+        if (amount > 0) {
+            ArrayList<JPaymentSelectReceipt> paymentWindows = new ArrayList<>();
+            for (Window window : Window.getWindows()) {
+                if (window instanceof JPaymentSelectReceipt) {
+                    paymentWindows.add((JPaymentSelectReceipt) window);
+                }
             }
+            return paymentWindows.get(paymentWindows.size()-1);
         }
-        return null;
+        else {
+            ArrayList<JPaymentSelectRefund> paymentWindows = new ArrayList<>();
+            for (Window window : Window.getWindows()) {
+                if (window instanceof JPaymentSelectRefund) {
+                    paymentWindows.add((JPaymentSelectRefund) window);
+                }
+            }
+            return paymentWindows.get(paymentWindows.size()-1);
+        }
+
     }
 
     /**