From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Owen1212055 <23108066+Owen1212055@users.noreply.github.com>
Date: Tue, 23 May 2023 22:33:36 -0400
Subject: [PATCH] Properly Cancel Usable Items

This fixes the bug causing cancelling PlayerInteractEvent to cause items to continue to be used despite being cancelled on the server.

For example, items being consumed but never finishing, shields being put up, etc.
The underlying issue of this is that the client modifies their synced data values, and so we have to (forcibly) resend
them in order for the client to reset their using item state.

diff --git a/src/main/java/net/minecraft/server/level/ServerPlayerGameMode.java b/src/main/java/net/minecraft/server/level/ServerPlayerGameMode.java
index f58386e952d29a16d160b628a23efbe102791277..82f26186156a487f29ad3abff3f68852e5b8a1f9 100644
--- a/src/main/java/net/minecraft/server/level/ServerPlayerGameMode.java
+++ b/src/main/java/net/minecraft/server/level/ServerPlayerGameMode.java
@@ -557,6 +557,7 @@ public class ServerPlayerGameMode {
             }
             // Paper end - extend Player Interact cancellation
             player.getBukkitEntity().updateInventory(); // SPIGOT-2867
+            this.player.resyncUsingItem(this.player); // Paper - Resend player's using item status
             enuminteractionresult = (event.useItemInHand() != Event.Result.ALLOW) ? InteractionResult.SUCCESS : InteractionResult.PASS;
         } else if (this.gameModeForPlayer == GameType.SPECTATOR) {
             MenuProvider itileinventory = iblockdata.getMenuProvider(world, blockposition);
@@ -600,6 +601,11 @@ public class ServerPlayerGameMode {
 
                 return enuminteractionresult1;
             }
+            // Paper start - Cancel only if cancelled + if the interact result is different from default response
+            else if (this.interactResult && this.interactResult != cancelledItem) {
+                this.player.resyncUsingItem(this.player);
+            }
+            // Paper end
         }
         return enuminteractionresult;
         // CraftBukkit end
diff --git a/src/main/java/net/minecraft/server/network/ServerGamePacketListenerImpl.java b/src/main/java/net/minecraft/server/network/ServerGamePacketListenerImpl.java
index 207576cbf4517d43a5159d7543db47782612c8c9..ccd6b734534a9f2b4205ee857ac650b26be74d5e 100644
--- a/src/main/java/net/minecraft/server/network/ServerGamePacketListenerImpl.java
+++ b/src/main/java/net/minecraft/server/network/ServerGamePacketListenerImpl.java
@@ -1951,6 +1951,7 @@ public class ServerGamePacketListenerImpl extends ServerCommonPacketListenerImpl
             }
 
             if (cancelled) {
+                this.player.resyncUsingItem(this.player); // Paper - Resend player's using item status
                 this.player.getBukkitEntity().updateInventory(); // SPIGOT-2524
                 return;
             }
diff --git a/src/main/java/net/minecraft/world/entity/LivingEntity.java b/src/main/java/net/minecraft/world/entity/LivingEntity.java
index f359f63ac8cf3133b63096dad4e3142c6c4b1cbf..bed0a01be1703aad8fbfa549d5799e3f84759f32 100644
--- a/src/main/java/net/minecraft/world/entity/LivingEntity.java
+++ b/src/main/java/net/minecraft/world/entity/LivingEntity.java
@@ -3813,6 +3813,11 @@ public abstract class LivingEntity extends Entity implements Attackable {
         return ((Byte) this.entityData.get(LivingEntity.DATA_LIVING_ENTITY_FLAGS) & 2) > 0 ? InteractionHand.OFF_HAND : InteractionHand.MAIN_HAND;
     }
 
+    // Paper start
+    public void resyncUsingItem(ServerPlayer serverPlayer) {
+        this.getEntityData().resendPossiblyDesyncedDataValues(java.util.List.of(DATA_LIVING_ENTITY_FLAGS), serverPlayer);
+    }
+    // Paper end
     private void updatingUsingItem() {
         if (this.isUsingItem()) {
             if (ItemStack.isSameItem(this.getItemInHand(this.getUsedItemHand()), this.useItem)) {