From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: William Blake Galbreath <Blake.Galbreath@GMail.com>
Date: Fri, 3 Jul 2020 11:58:56 -0500
Subject: [PATCH] Add PrepareResultEvent

Adds a new event for all crafting stations that generate a result slot item

Anvil, Grindstone and Smithing now extend this event

diff --git a/src/main/java/net/minecraft/world/inventory/AnvilMenu.java b/src/main/java/net/minecraft/world/inventory/AnvilMenu.java
index ffda2c984c5683edb38a56f04c53b0ea339e08fc..d685511104ac552dfc9ae2111e1bfb60fa812102 100644
--- a/src/main/java/net/minecraft/world/inventory/AnvilMenu.java
+++ b/src/main/java/net/minecraft/world/inventory/AnvilMenu.java
@@ -327,6 +327,7 @@ public class AnvilMenu extends ItemCombinerMenu {
             }
 
             this.createResult();
+            org.bukkit.craftbukkit.event.CraftEventFactory.callPrepareResultEvent(this, RESULT_SLOT); // Paper - Add PrepareResultEvent
             return true;
         } else {
             return false;
diff --git a/src/main/java/net/minecraft/world/inventory/CartographyTableMenu.java b/src/main/java/net/minecraft/world/inventory/CartographyTableMenu.java
index 11d7bf4f90083991cfc8c6c5f9a1e8ad6a162843..c52c4c4210bc6ae082443318d9795c48c816aba6 100644
--- a/src/main/java/net/minecraft/world/inventory/CartographyTableMenu.java
+++ b/src/main/java/net/minecraft/world/inventory/CartographyTableMenu.java
@@ -152,6 +152,7 @@ public class CartographyTableMenu extends AbstractContainerMenu {
             this.setupResultSlot(itemstack, itemstack1, itemstack2);
         }
 
+        org.bukkit.craftbukkit.event.CraftEventFactory.callPrepareResultEvent(this, RESULT_SLOT); // Paper - Add PrepareResultEvent
     }
 
     private void setupResultSlot(ItemStack map, ItemStack item, ItemStack oldResult) {
diff --git a/src/main/java/net/minecraft/world/inventory/GrindstoneMenu.java b/src/main/java/net/minecraft/world/inventory/GrindstoneMenu.java
index 637d77d6b07ff9ee5ac1cb0470cbefcba5c7495e..15ec798e149d80aace186f84b9236ddeaba690c3 100644
--- a/src/main/java/net/minecraft/world/inventory/GrindstoneMenu.java
+++ b/src/main/java/net/minecraft/world/inventory/GrindstoneMenu.java
@@ -160,6 +160,7 @@ public class GrindstoneMenu extends AbstractContainerMenu {
         super.slotsChanged(inventory);
         if (inventory == this.repairSlots) {
             this.createResult();
+            org.bukkit.craftbukkit.event.CraftEventFactory.callPrepareResultEvent(this, RESULT_SLOT); // Paper - Add PrepareResultEvent
         }
 
     }
diff --git a/src/main/java/net/minecraft/world/inventory/ItemCombinerMenu.java b/src/main/java/net/minecraft/world/inventory/ItemCombinerMenu.java
index 62432c347b86fc79ab529a7dde66bef32d0424dd..be840717e180b6b5abd14db6cc9263349737f9a3 100644
--- a/src/main/java/net/minecraft/world/inventory/ItemCombinerMenu.java
+++ b/src/main/java/net/minecraft/world/inventory/ItemCombinerMenu.java
@@ -110,6 +110,7 @@ public abstract class ItemCombinerMenu extends AbstractContainerMenu {
         super.slotsChanged(inventory);
         if (inventory == this.inputSlots) {
             this.createResult();
+            org.bukkit.craftbukkit.event.CraftEventFactory.callPrepareResultEvent(this, this instanceof SmithingMenu ? 3 : 2); // Paper - Add PrepareResultEvent
         }
 
     }
diff --git a/src/main/java/net/minecraft/world/inventory/LoomMenu.java b/src/main/java/net/minecraft/world/inventory/LoomMenu.java
index 69ed0753c224cb7746762b4b94c4d79d608951b8..2de558dd205a1078fdcac1bce256d059b9bf5d5f 100644
--- a/src/main/java/net/minecraft/world/inventory/LoomMenu.java
+++ b/src/main/java/net/minecraft/world/inventory/LoomMenu.java
@@ -249,7 +249,8 @@ public class LoomMenu extends AbstractContainerMenu {
                 this.resultSlot.set(ItemStack.EMPTY);
             }
 
-            this.broadcastChanges();
+            // this.broadcastChanges(); // Paper - Add PrepareResultEvent; done below
+            org.bukkit.craftbukkit.event.CraftEventFactory.callPrepareResultEvent(this, 3); // Paper - Add PrepareResultEvent
         } else {
             this.resultSlot.set(ItemStack.EMPTY);
             this.selectablePatterns = List.of();
diff --git a/src/main/java/net/minecraft/world/inventory/SmithingMenu.java b/src/main/java/net/minecraft/world/inventory/SmithingMenu.java
index 0735705def4f9505b7f16df2497cc78bbf5a8373..86e51fcce767d265ee0d3beb611be2119085830b 100644
--- a/src/main/java/net/minecraft/world/inventory/SmithingMenu.java
+++ b/src/main/java/net/minecraft/world/inventory/SmithingMenu.java
@@ -121,6 +121,7 @@ public class SmithingMenu extends ItemCombinerMenu {
             }
         }
 
+        org.bukkit.craftbukkit.event.CraftEventFactory.callPrepareResultEvent(this, RESULT_SLOT); // Paper - Add PrepareResultEvent
     }
 
     @Override
diff --git a/src/main/java/net/minecraft/world/inventory/StonecutterMenu.java b/src/main/java/net/minecraft/world/inventory/StonecutterMenu.java
index 30ea1f9e97db86a2ad7baeea4f5a76c821874daa..5b4f03128499b0c1a4b8c5f5ccd17e4bdb391e81 100644
--- a/src/main/java/net/minecraft/world/inventory/StonecutterMenu.java
+++ b/src/main/java/net/minecraft/world/inventory/StonecutterMenu.java
@@ -182,6 +182,7 @@ public class StonecutterMenu extends AbstractContainerMenu {
             this.setupRecipeList(inventory, itemstack);
         }
 
+        org.bukkit.craftbukkit.event.CraftEventFactory.callPrepareResultEvent(this, RESULT_SLOT); // Paper - Add PrepareResultEvent
     }
 
     private static SingleRecipeInput createRecipeInput(Container inventory) {
diff --git a/src/main/java/org/bukkit/craftbukkit/event/CraftEventFactory.java b/src/main/java/org/bukkit/craftbukkit/event/CraftEventFactory.java
index 752aba27c3eb9815bdd2b4683483c70e891711e7..44fd82bf887e5c6d946d7eed18e21f966efda9de 100644
--- a/src/main/java/org/bukkit/craftbukkit/event/CraftEventFactory.java
+++ b/src/main/java/org/bukkit/craftbukkit/event/CraftEventFactory.java
@@ -1681,6 +1681,12 @@ public class CraftEventFactory {
     }
 
     public static PrepareAnvilEvent callPrepareAnvilEvent(AnvilView view, ItemStack item) {
+        // Paper start - Add PrepareResultEvent
+        if (true) {
+            view.getTopInventory().setItem(net.minecraft.world.inventory.AnvilMenu.RESULT_SLOT, CraftItemStack.asCraftMirror(item));
+            return null; // verify nothing uses return - disable event: handled below in PrepareResult
+        }
+        // Paper end - Add PrepareResultEvent
         PrepareAnvilEvent event = new PrepareAnvilEvent(view, CraftItemStack.asCraftMirror(item).clone());
         event.getView().getPlayer().getServer().getPluginManager().callEvent(event);
         event.getInventory().setItem(2, event.getResult());
@@ -1688,6 +1694,12 @@ public class CraftEventFactory {
     }
 
     public static PrepareGrindstoneEvent callPrepareGrindstoneEvent(InventoryView view, ItemStack item) {
+        // Paper start - Add PrepareResultEvent
+        if (true) {
+            view.getTopInventory().setItem(net.minecraft.world.inventory.GrindstoneMenu.RESULT_SLOT, CraftItemStack.asCraftMirror(item));
+            return null; // verify nothing uses return - disable event: handled below in PrepareResult
+        }
+        // Paper end - Add PrepareResultEvent
         PrepareGrindstoneEvent event = new PrepareGrindstoneEvent(view, CraftItemStack.asCraftMirror(item).clone());
         event.getView().getPlayer().getServer().getPluginManager().callEvent(event);
         event.getInventory().setItem(2, event.getResult());
@@ -1695,12 +1707,39 @@ public class CraftEventFactory {
     }
 
     public static PrepareSmithingEvent callPrepareSmithingEvent(InventoryView view, ItemStack item) {
+        // Paper start - Add PrepareResultEvent
+        if (true) {
+            view.getTopInventory().setItem(net.minecraft.world.inventory.SmithingMenu.RESULT_SLOT, CraftItemStack.asCraftMirror(item));
+            return null; // verify nothing uses return - disable event: handled below in PrepareResult
+        }
+        // Paper end - Add PrepareResultEvent
         PrepareSmithingEvent event = new PrepareSmithingEvent(view, CraftItemStack.asCraftMirror(item).clone());
         event.getView().getPlayer().getServer().getPluginManager().callEvent(event);
         event.getInventory().setResult(event.getResult());
         return event;
     }
 
+    // Paper start - Add PrepareResultEvent
+    public static void callPrepareResultEvent(AbstractContainerMenu container, int resultSlot) {
+        final com.destroystokyo.paper.event.inventory.PrepareResultEvent event;
+        InventoryView view = container.getBukkitView();
+        org.bukkit.inventory.ItemStack origItem = view.getTopInventory().getItem(resultSlot);
+        CraftItemStack result = origItem != null ? CraftItemStack.asCraftCopy(origItem) : null;
+        if (view.getTopInventory() instanceof org.bukkit.inventory.AnvilInventory && view instanceof AnvilView anvilView) {
+            event = new PrepareAnvilEvent(anvilView, result);
+        } else if (view.getTopInventory() instanceof org.bukkit.inventory.GrindstoneInventory) {
+            event = new PrepareGrindstoneEvent(view, result);
+        } else if (view.getTopInventory() instanceof org.bukkit.inventory.SmithingInventory) {
+            event = new PrepareSmithingEvent(view, result);
+        } else {
+            event = new com.destroystokyo.paper.event.inventory.PrepareResultEvent(view, result);
+        }
+        event.callEvent();
+        event.getInventory().setItem(resultSlot, event.getResult());
+        container.broadcastChanges();;
+    }
+    // Paper end - Add PrepareResultEvent
+
     /**
      * Mob spawner event.
      */