Fix MerchantGui onTrade number of calls on shift click

src/main/java/eu/pb4/sgui/api/gui/MerchantGui.java

@@ -183,10 +183,18 @@ public TradeOffer getSelectedTrade() {
      * @param offer the trade offer being done
      * @return if the trade should complete
      */
-    public boolean onTrade(TradeOffer offer) {
+    public boolean shouldTrade(TradeOffer offer) {
         return true;
     }
 
+    /**
+     * Runs after a trade has been completed.
+     *
+     * @param offer the trade offer being done
+     */
+    public void onTrade(TradeOffer offer) {
+    }
+
     /**
      * Runs when a suggested trade is placed into the selling slot.
      *

src/main/java/eu/pb4/sgui/virtual/merchant/VirtualMerchant.java

@@ -5,6 +5,7 @@
 import net.minecraft.server.network.ServerPlayerEntity;
 import net.minecraft.text.Text;
 import net.minecraft.village.SimpleMerchant;
+import net.minecraft.village.TradeOffer;
 
 public class VirtualMerchant extends SimpleMerchant {
 
@@ -48,4 +49,14 @@ public void sendOffers(PlayerEntity player, Text test, int levelProgress) {
             ((VirtualMerchantScreenHandler) player.currentScreenHandler).getGui().sendUpdate();
         }
     }
+
+    @Override
+    public void trade(TradeOffer offer) {
+        super.trade(offer);
+        ServerPlayerEntity player = (ServerPlayerEntity) this.getCustomer();
+        assert player != null;
+        if (player.currentScreenHandler instanceof VirtualMerchantScreenHandler) {
+            ((VirtualMerchantScreenHandler) player.currentScreenHandler).getGui().onTrade(offer);
+        }
+    }
 }

src/main/java/eu/pb4/sgui/virtual/merchant/VirtualTradeOutputSlot.java

@@ -18,7 +18,7 @@ public VirtualTradeOutputSlot(PlayerEntity player, VirtualMerchant merchant, Mer
     public boolean canTakeItems(PlayerEntity playerEntity) {
         TradeOffer tradeOffer = this.merchantInventory.getTradeOffer();
         VirtualMerchantScreenHandler handler = (VirtualMerchantScreenHandler) playerEntity.currentScreenHandler;
-        return tradeOffer != null && handler.getGui().onTrade(tradeOffer);
+        return tradeOffer != null && handler.getGui().shouldTrade(tradeOffer);
     }
 
 }

src/testmod/java/eu/pb4/sgui/testmod/SGuiTest.java

@@ -360,7 +360,7 @@ public void onSelectTrade(TradeOffer offer) {
                 }
 
                 @Override
-                public boolean onTrade(TradeOffer offer) {
+                public boolean shouldTrade(TradeOffer offer) {
                     return player.isCreative();
                 }