From 861c3fa189510a3970d34c35bd7bf053a6be433e Mon Sep 17 00:00:00 2001
From: Shane Freeder <theboyetronic@gmail.com>
Date: Sun, 11 Feb 2018 10:43:46 +0000
Subject: [PATCH] Extend Player Interact cancellation

GUIs are opened on the client, meaning that the server cannot block them from opening,
However, it is possible to close these GUIs from the server.

Flower pots are also not updated on the client when interaction is cancelled, this patch
also resolves this.

Update adjacent blocks of doors, double plants, pistons and beds
when cancelling interaction.

diff --git a/src/main/java/net/minecraft/server/PlayerInteractManager.java b/src/main/java/net/minecraft/server/PlayerInteractManager.java
index 6e524353b5..4a439ef4ca 100644
--- a/src/main/java/net/minecraft/server/PlayerInteractManager.java
+++ b/src/main/java/net/minecraft/server/PlayerInteractManager.java
@@ -110,6 +110,11 @@ public class PlayerInteractManager {
         if (event.isCancelled()) {
             // Let the client know the block still exists
             ((EntityPlayer) this.player).playerConnection.sendPacket(new PacketPlayOutBlockChange(this.world, blockposition));
+            // Paper start - brute force neighbor blocks for any attached blocks
+            for (EnumDirection dir : EnumDirection.values()) {
+                ((EntityPlayer) this.player).playerConnection.sendPacket(new PacketPlayOutBlockChange(world, blockposition.shift(dir)));
+            }
+            // Paper end
             // Update any tile entity data for this block
             TileEntity tileentity = this.world.getTileEntity(blockposition);
             if (tileentity != null) {
@@ -460,7 +465,25 @@ public class PlayerInteractManager {
                 ((EntityPlayer) entityhuman).playerConnection.sendPacket(new PacketPlayOutBlockChange(world, bottom ? blockposition.up() : blockposition.down()));
             } else if (iblockdata.getBlock() instanceof BlockCake) {
                 ((EntityPlayer) entityhuman).getBukkitEntity().sendHealthUpdate(); // SPIGOT-1341 - reset health for cake
+            // Paper start  - extend Player Interact cancellation // TODO: consider merging this into the extracted method
+            } else if (iblockdata.getBlock() instanceof BlockStructure) {
+                    ((EntityPlayer) entityhuman).playerConnection.sendPacket(new PacketPlayOutCloseWindow());
+            } else if (iblockdata.getBlock() instanceof BlockCommand) {
+                    ((EntityPlayer) entityhuman).playerConnection.sendPacket(new PacketPlayOutCloseWindow());
+            } else if (iblockdata.getBlock() instanceof BlockFlowerPot) {
+                // Send a block change to air and then send back the correct block, just to make the client happy
+                PacketPlayOutBlockChange packet = new PacketPlayOutBlockChange(this.world, blockposition);
+                packet.block = Blocks.AIR.getBlockData();
+                this.player.playerConnection.sendPacket(packet);
+
+                this.player.playerConnection.sendPacket(new PacketPlayOutBlockChange(this.world, blockposition));
+
+                TileEntity tileentity = this.world.getTileEntity(blockposition);
+                if (tileentity != null) {
+                    player.playerConnection.sendPacket(tileentity.getUpdatePacket());
+                }
             }
+            // Paper end - extend Player Interact cancellation
             ((EntityPlayer) entityhuman).getBukkitEntity().updateInventory(); // SPIGOT-2867
             enuminteractionresult = (event.useItemInHand() != Event.Result.ALLOW) ? EnumInteractionResult.SUCCESS : EnumInteractionResult.PASS;
         } else if (this.gamemode == EnumGamemode.SPECTATOR) {
-- 
2.18.0