From 69aecad8ffaaa88760f8c3b0b152cc80ec669eb0 Mon Sep 17 00:00:00 2001
From: Aikar <aikar@aikar.co>
Date: Wed, 26 Jul 2017 21:12:15 -0400
Subject: [PATCH] Fix Recipe Books


diff --git a/src/main/java/net/minecraft/server/PlayerConnection.java b/src/main/java/net/minecraft/server/PlayerConnection.java
index 682211cdd..034081cbe 100644
--- a/src/main/java/net/minecraft/server/PlayerConnection.java
+++ b/src/main/java/net/minecraft/server/PlayerConnection.java
@@ -2027,12 +2027,6 @@ public class PlayerConnection implements PacketListenerPlayIn, ITickable {
     public void a(PacketPlayInAutoRecipe packetplayinautorecipe) {
         PlayerConnectionUtils.ensureMainThread(packetplayinautorecipe, this, this.player.x());
         this.player.resetIdleTimer();
-        // CraftBukkit start
-        if (!player.getBukkitEntity().hasPermission("minecraft.autocraft")) {
-            player.getBukkitEntity().updateInventory();
-            return;
-        }
-        // CraftBukkit end
         if (this.player.activeContainer.windowId == packetplayinautorecipe.a() && this.player.activeContainer.c(this.player)) {
             this.player.playerConnection.sendPacket(new PacketPlayOutTransaction(packetplayinautorecipe.a(), packetplayinautorecipe.b(), true));
             Iterator iterator;
@@ -2046,10 +2040,19 @@ public class PlayerConnection implements PacketListenerPlayIn, ITickable {
                 while (iterator.hasNext()) {
                     packetplayinautorecipe_a = (PacketPlayInAutoRecipe.a) iterator.next();
                     itemstack = this.player.activeContainer.getSlot(packetplayinautorecipe_a.b).getItem();
-                    if (this.a(packetplayinautorecipe_a.a, itemstack)) {
+                    // Paper start - improve validation
+                    int toSlot = packetplayinautorecipe_a.c;
+                    ItemStack to = toSlot != -1 ? this.player.inventory.getItem(toSlot) : ItemStack.a;
+                    ItemStack ref = packetplayinautorecipe_a.a;
+                    if (this.a(ref, itemstack) && (to.isEmpty() || this.a(ref, to)) && (ref.getCount() + to.getCount() <= ref.getMaxStackSize())) {
+                        // Paper end
                         i = packetplayinautorecipe_a.a.getCount();
                         if (packetplayinautorecipe_a.c == -1) {
-                            this.player.drop(packetplayinautorecipe_a.a, true);
+                            // Paper start
+                            this.player.drop(itemstack, true);
+                            this.player.activeContainer.setItem(packetplayinautorecipe_a.b, ItemStack.a);
+                            continue;
+                            // Paper end
                         } else {
                             ItemStack itemstack1 = this.player.inventory.getItem(packetplayinautorecipe_a.c);
 
@@ -2066,6 +2069,12 @@ public class PlayerConnection implements PacketListenerPlayIn, ITickable {
                             itemstack.subtract(i);
                         }
                     }
+                    // Paper start
+                    else {
+                        this.player.getBukkitEntity().updateInventory();
+                        return;
+                    }
+                    // Paper end
                 }
             }
 
@@ -2075,7 +2084,11 @@ public class PlayerConnection implements PacketListenerPlayIn, ITickable {
                 while (iterator.hasNext()) {
                     packetplayinautorecipe_a = (PacketPlayInAutoRecipe.a) iterator.next();
                     itemstack = this.player.inventory.getItem(packetplayinautorecipe_a.c);
-                    if (this.a(packetplayinautorecipe_a.a, itemstack)) {
+                    // Paper start
+                    ItemStack ref = packetplayinautorecipe_a.a;
+                    ItemStack to = this.player.activeContainer.getSlot(packetplayinautorecipe_a.b).getItem();
+                    if (this.a(ref, itemstack) && (to.isEmpty() || this.a(ref, to)) && (ref.getCount() + to.getCount() <= ref.getMaxStackSize())) {
+                        // Paper end
                         i = packetplayinautorecipe_a.a.getCount();
                         if (itemstack.getCount() == i) {
                             this.player.inventory.splitWithoutUpdate(packetplayinautorecipe_a.c);
@@ -2083,8 +2096,17 @@ public class PlayerConnection implements PacketListenerPlayIn, ITickable {
                             itemstack.subtract(i);
                         }
 
-                        this.player.activeContainer.b(packetplayinautorecipe_a.b, packetplayinautorecipe_a.a);
+                        // Paper start
+                        if (to.isEmpty()) {
+                            this.player.activeContainer.b(packetplayinautorecipe_a.b, packetplayinautorecipe_a.a);
+                        } else {
+                            to.add(i);
+                        }
+                    } else {
+                        this.player.getBukkitEntity().updateInventory();
+                        return;
                     }
+                    // Paper end
                 }
             }
 
-- 
2.13.0