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 34ecfb89372f459117db99d57a7edd6f681bbe8a..baf3e79489e310f443788bc917c553ae7ea86c89 100644
--- a/src/main/java/net/minecraft/server/level/ServerPlayerGameMode.java
+++ b/src/main/java/net/minecraft/server/level/ServerPlayerGameMode.java
@@ -562,6 +562,7 @@ 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);
@@ -605,6 +606,11 @@ 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 afbc246a2dc55f0f1576c0468118ef80671a034e..1c86eaf44e6c797a51e69f14e08bb9a3f91b4c20 100644
--- a/src/main/java/net/minecraft/server/network/ServerGamePacketListenerImpl.java
+++ b/src/main/java/net/minecraft/server/network/ServerGamePacketListenerImpl.java
@@ -1923,6 +1923,7 @@ 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 8b0d715d3adf4694cd93bbf1152dd2e20d3d44de..485b7c3e3a13ad8fdbf0b17fef31e05803f1615e 100644
--- a/src/main/java/net/minecraft/world/entity/LivingEntity.java
+++ b/src/main/java/net/minecraft/world/entity/LivingEntity.java
@@ -3814,6 +3814,11 @@ 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)) {