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 dff005cc860fc5ff0759d6e35502deebd00943ed..ae0ba6b0e1f0bee3c3a701b22725171e499b97a3 100644
--- a/src/main/java/net/minecraft/world/inventory/AnvilMenu.java
+++ b/src/main/java/net/minecraft/world/inventory/AnvilMenu.java
@@ -333,6 +333,7 @@ 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 5b31d09b158c694b3e54ab3a228817accaa00a0c..8b72d1fd551dcb113f4137aee441a9531c00288a 100644
--- a/src/main/java/net/minecraft/world/inventory/CartographyTableMenu.java
+++ b/src/main/java/net/minecraft/world/inventory/CartographyTableMenu.java
@@ -140,6 +140,7 @@ 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 13bc52bc856031c930370828b0381e43920aabd2..8e58dbb4b110338dfe8add26697d0b1c9ec5fa9c 100644
--- a/src/main/java/net/minecraft/world/inventory/GrindstoneMenu.java
+++ b/src/main/java/net/minecraft/world/inventory/GrindstoneMenu.java
@@ -148,6 +148,7 @@ 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 594a387d7e3a67da02ea54b4f259426df2eb21a2..4734dd90f2a66e1ac7a64b35ecd62a630108cf07 100644
--- a/src/main/java/net/minecraft/world/inventory/ItemCombinerMenu.java
+++ b/src/main/java/net/minecraft/world/inventory/ItemCombinerMenu.java
@@ -96,6 +96,7 @@ 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 d988747ccb81ca74db8ce14fea49d13c9c1b4476..58470d8e9a4ceb1eca05b342481ed8260588e225 100644
--- a/src/main/java/net/minecraft/world/inventory/LoomMenu.java
+++ b/src/main/java/net/minecraft/world/inventory/LoomMenu.java
@@ -237,7 +237,8 @@ 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 4b0d07a22cb922aa5ef0c99279663158a5918f1f..89d2f26504bb072c2d75af4ec600ca123e10a600 100644
--- a/src/main/java/net/minecraft/world/inventory/SmithingMenu.java
+++ b/src/main/java/net/minecraft/world/inventory/SmithingMenu.java
@@ -115,6 +115,7 @@ public class SmithingMenu extends ItemCombinerMenu {
             this.hasRecipeError.set(flag ? 1 : 0);
         }
 
+        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 0fb0ee5b22dc96c48d68e4391fd71b03d4e799f0..97837d1baf6b929a50e5562ef466050e70c2c8b1 100644
--- a/src/main/java/net/minecraft/world/inventory/StonecutterMenu.java
+++ b/src/main/java/net/minecraft/world/inventory/StonecutterMenu.java
@@ -170,6 +170,7 @@ public class StonecutterMenu extends AbstractContainerMenu {
             this.setupRecipeList(itemstack);
         }
 
+        org.bukkit.craftbukkit.event.CraftEventFactory.callPrepareResultEvent(this, RESULT_SLOT); // Paper - Add PrepareResultEvent
     }
 
     private void setupRecipeList(ItemStack stack) {
diff --git a/src/main/java/org/bukkit/craftbukkit/event/CraftEventFactory.java b/src/main/java/org/bukkit/craftbukkit/event/CraftEventFactory.java
index b8e1a7251f9fa09f03b00b387013af1c623a1e52..f8ec0bca1683d172bc673afc28cf9f7b76e26130 100644
--- a/src/main/java/org/bukkit/craftbukkit/event/CraftEventFactory.java
+++ b/src/main/java/org/bukkit/craftbukkit/event/CraftEventFactory.java
@@ -1679,6 +1679,12 @@ 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());
@@ -1686,6 +1692,12 @@ 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());
@@ -1693,12 +1705,39 @@ 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.
      */