From bac28e529e52e14d9d21ff4ac3d62e6e35079395 Mon Sep 17 00:00:00 2001
From: Aikar <aikar@aikar.co>
Date: Thu, 28 May 2015 23:00:19 -0400
Subject: [PATCH] Handle Item Meta Inconsistencies

First, Enchantment order would blow away seeing 2 items as the same,
however the Client forces enchantment list in a certain order, as well
as does the /enchant command. Anvils can insert it into forced order,
causing 2 same items to be considered different.

This change makes unhandled NBT Tags and Enchantments use a sorted tree map,
so they will always be in a consistent order.

Additionally, the old enchantment API was never updated when ItemMeta
was added, resulting in 2 different ways to modify an items enchantments.

For consistency, the old API methods now forward to use the
ItemMeta API equivalents, and should deprecate the old API's.

diff --git a/src/main/java/net/minecraft/server/ItemStack.java b/src/main/java/net/minecraft/server/ItemStack.java
index 82d72ea158..5047a57e9b 100644
--- a/src/main/java/net/minecraft/server/ItemStack.java
+++ b/src/main/java/net/minecraft/server/ItemStack.java
@@ -57,6 +57,22 @@ public final class ItemStack {
     }
 
     // CraftBukkit start
+    // Paper start
+    private static final java.util.Comparator<NBTTagCompound> enchantSorter = java.util.Comparator.comparingInt(o -> o.getShort("id"));
+    private void processEnchantOrder(NBTTagCompound tag) {
+        if (tag == null || !tag.hasKeyOfType("ench", 9)) {
+            return;
+        }
+        NBTTagList list = tag.getList("ench", 10);
+        if (list.size() < 2) {
+            return;
+        }
+        try {
+            list.sort(enchantSorter); // Paper
+        } catch (Exception ignored) {}
+    }
+    // Paper end
+
     public ItemStack(Item item, int i, int j) {
         this(item, i, j, true);
     }
@@ -114,6 +130,7 @@ public final class ItemStack {
         if (nbttagcompound.hasKeyOfType("tag", 10)) {
             // CraftBukkit start - make defensive copy as this data may be coming from the save thread
             this.tag = (NBTTagCompound) nbttagcompound.getCompound("tag").clone();
+            processEnchantOrder(this.tag); // Paper
             if (this.item != null) {
                 this.item.a(this.tag);
                 // CraftBukkit end
@@ -597,6 +614,7 @@ public final class ItemStack {
     // Paper end
     public void setTag(@Nullable NBTTagCompound nbttagcompound) {
         this.tag = nbttagcompound;
+        processEnchantOrder(this.tag); // Paper
     }
 
     public String getName() {
@@ -670,6 +688,7 @@ public final class ItemStack {
         nbttagcompound.setShort("id", (short) Enchantment.getId(enchantment));
         nbttagcompound.setShort("lvl", (short) ((byte) i));
         nbttaglist.add(nbttagcompound);
+        processEnchantOrder(nbttagcompound); // Paper
     }
 
     public boolean hasEnchantments() {
diff --git a/src/main/java/net/minecraft/server/NBTTagList.java b/src/main/java/net/minecraft/server/NBTTagList.java
index ca9eb2f3b2..576c3b7141 100644
--- a/src/main/java/net/minecraft/server/NBTTagList.java
+++ b/src/main/java/net/minecraft/server/NBTTagList.java
@@ -14,6 +14,12 @@ public class NBTTagList extends NBTBase {
 
     private static final Logger b = LogManager.getLogger();
     public List<NBTBase> list = Lists.newArrayList(); // Paper
+    // Paper start
+    public void sort(java.util.Comparator<? extends NBTBase> comparator) {
+        //noinspection unchecked
+        java.util.Collections.sort(list, (java.util.Comparator<NBTBase>) comparator);
+    }
+    // Paper end
     private byte type = 0;
 
     public NBTTagList() {}
diff --git a/src/main/java/org/bukkit/craftbukkit/inventory/CraftItemStack.java b/src/main/java/org/bukkit/craftbukkit/inventory/CraftItemStack.java
index fb1dc542dd..8ffe18b092 100644
--- a/src/main/java/org/bukkit/craftbukkit/inventory/CraftItemStack.java
+++ b/src/main/java/org/bukkit/craftbukkit/inventory/CraftItemStack.java
@@ -4,6 +4,7 @@ import static org.bukkit.craftbukkit.inventory.CraftMetaItem.ENCHANTMENTS;
 import static org.bukkit.craftbukkit.inventory.CraftMetaItem.ENCHANTMENTS_ID;
 import static org.bukkit.craftbukkit.inventory.CraftMetaItem.ENCHANTMENTS_LVL;
 
+import java.util.Iterator;
 import java.util.Map;
 
 import net.minecraft.server.EnchantmentManager;
@@ -183,28 +184,11 @@ public final class CraftItemStack extends ItemStack {
     public void addUnsafeEnchantment(Enchantment ench, int level) {
         Validate.notNull(ench, "Cannot add null enchantment");
 
-        if (!makeTag(handle)) {
-            return;
-        }
-        NBTTagList list = getEnchantmentList(handle);
-        if (list == null) {
-            list = new NBTTagList();
-            handle.getTag().set(ENCHANTMENTS.NBT, list);
-        }
-        int size = list.size();
-
-        for (int i = 0; i < size; i++) {
-            NBTTagCompound tag = (NBTTagCompound) list.get(i);
-            short id = tag.getShort(ENCHANTMENTS_ID.NBT);
-            if (id == ench.getId()) {
-                tag.setShort(ENCHANTMENTS_LVL.NBT, (short) level);
-                return;
-            }
-        }
-        NBTTagCompound tag = new NBTTagCompound();
-        tag.setShort(ENCHANTMENTS_ID.NBT, (short) ench.getId());
-        tag.setShort(ENCHANTMENTS_LVL.NBT, (short) level);
-        list.add(tag);
+        // Paper start - Replace whole method
+        final ItemMeta itemMeta = getItemMeta();
+        itemMeta.addEnchant(ench, level, true);
+        setItemMeta(itemMeta);
+        // Paper end
     }
 
     static boolean makeTag(net.minecraft.server.ItemStack item) {
@@ -221,66 +205,31 @@ public final class CraftItemStack extends ItemStack {
 
     @Override
     public boolean containsEnchantment(Enchantment ench) {
-        return getEnchantmentLevel(ench) > 0;
+        return hasItemMeta() && getItemMeta().hasEnchant(ench); // Paper - use meta
     }
 
     @Override
     public int getEnchantmentLevel(Enchantment ench) {
-        Validate.notNull(ench, "Cannot find null enchantment");
-        if (handle == null) {
-            return 0;
-        }
-        return EnchantmentManager.getEnchantmentLevel(CraftEnchantment.getRaw(ench), handle);
+        return hasItemMeta() ? getItemMeta().getEnchantLevel(ench) : 0; // Pape - replace entire method with meta
     }
 
     @Override
     public int removeEnchantment(Enchantment ench) {
         Validate.notNull(ench, "Cannot remove null enchantment");
-
-        NBTTagList list = getEnchantmentList(handle), listCopy;
-        if (list == null) {
-            return 0;
+        // Paper start - replace entire method
+        final ItemMeta itemMeta = getItemMeta();
+        int level = itemMeta.getEnchantLevel(ench);
+        if (level > 0) {
+            itemMeta.removeEnchant(ench);
+            setItemMeta(itemMeta);
         }
-        int index = Integer.MIN_VALUE;
-        int level = Integer.MIN_VALUE;
-        int size = list.size();
-
-        for (int i = 0; i < size; i++) {
-            NBTTagCompound enchantment = (NBTTagCompound) list.get(i);
-            int id = 0xffff & enchantment.getShort(ENCHANTMENTS_ID.NBT);
-            if (id == ench.getId()) {
-                index = i;
-                level = 0xffff & enchantment.getShort(ENCHANTMENTS_LVL.NBT);
-                break;
-            }
-        }
-
-        if (index == Integer.MIN_VALUE) {
-            return 0;
-        }
-        if (size == 1) {
-            handle.getTag().remove(ENCHANTMENTS.NBT);
-            if (handle.getTag().isEmpty()) {
-                handle.setTag(null);
-            }
-            return level;
-        }
-
-        // This is workaround for not having an index removal
-        listCopy = new NBTTagList();
-        for (int i = 0; i < size; i++) {
-            if (i != index) {
-                listCopy.add(list.get(i));
-            }
-        }
-        handle.getTag().set(ENCHANTMENTS.NBT, listCopy);
-
         return level;
+        // Paper end
     }
 
     @Override
     public Map<Enchantment, Integer> getEnchantments() {
-        return getEnchantments(handle);
+        return hasItemMeta() ? getItemMeta().getEnchants() : ImmutableMap.<Enchantment, Integer>of(); // Paper - use Item Meta
     }
 
     static Map<Enchantment, Integer> getEnchantments(net.minecraft.server.ItemStack item) {
diff --git a/src/main/java/org/bukkit/craftbukkit/inventory/CraftMetaItem.java b/src/main/java/org/bukkit/craftbukkit/inventory/CraftMetaItem.java
index c743ae066e..0cdc8007a4 100644
--- a/src/main/java/org/bukkit/craftbukkit/inventory/CraftMetaItem.java
+++ b/src/main/java/org/bukkit/craftbukkit/inventory/CraftMetaItem.java
@@ -6,13 +6,8 @@ import java.lang.annotation.RetentionPolicy;
 import java.lang.annotation.Target;
 import java.lang.reflect.Constructor;
 import java.lang.reflect.InvocationTargetException;
-import java.util.ArrayList;
-import java.util.Collection;
-import java.util.HashMap;
-import java.util.List;
-import java.util.Map;
-import java.util.NoSuchElementException;
 
+import com.google.common.collect.ImmutableSortedMap;
 import net.minecraft.server.NBTBase;
 import net.minecraft.server.NBTTagCompound;
 import net.minecraft.server.NBTTagList;
@@ -38,10 +33,18 @@ import com.google.common.collect.Sets;
 import java.io.ByteArrayInputStream;
 import java.io.ByteArrayOutputStream;
 import java.io.IOException;
+import java.util.ArrayList;
 import java.util.Arrays;
+import java.util.Collection;
+import java.util.Comparator;
 import java.util.EnumSet;
+import java.util.HashMap;
 import java.util.HashSet;
+import java.util.List;
+import java.util.Map;
+import java.util.NoSuchElementException;
 import java.util.Set;
+import java.util.TreeMap;
 import java.util.logging.Level;
 import java.util.logging.Logger;
 import net.minecraft.server.NBTCompressedStreamTools;
@@ -226,7 +229,7 @@ class CraftMetaItem implements ItemMeta, Repairable {
     private String displayName;
     private String locName;
     private List<String> lore;
-    private Map<Enchantment, Integer> enchantments;
+    private EnchantmentMap enchantments; // Paper
     private int repairCost;
     private int hideFlag;
     private boolean unbreakable;
@@ -234,7 +237,7 @@ class CraftMetaItem implements ItemMeta, Repairable {
     private static final Set<String> HANDLED_TAGS = Sets.newHashSet();
 
     private NBTTagCompound internalTag;
-    private final Map<String, NBTBase> unhandledTags = new HashMap<String, NBTBase>();
+    private final Map<String, NBTBase> unhandledTags = new TreeMap<>(); // Paper
 
     CraftMetaItem(CraftMetaItem meta) {
         if (meta == null) {
@@ -249,7 +252,7 @@ class CraftMetaItem implements ItemMeta, Repairable {
         }
 
         if (meta.enchantments != null) { // Spigot
-            this.enchantments = new HashMap<Enchantment, Integer>(meta.enchantments);
+            this.enchantments = new EnchantmentMap(meta.enchantments); // Paper
         }
 
         this.repairCost = meta.repairCost;
@@ -470,13 +473,13 @@ class CraftMetaItem implements ItemMeta, Repairable {
         }
     }
 
-    static Map<Enchantment, Integer> buildEnchantments(NBTTagCompound tag, ItemMetaKey key) {
+    static EnchantmentMap buildEnchantments(NBTTagCompound tag, ItemMetaKey key) { // Paper
         if (!tag.hasKey(key.NBT)) {
             return null;
         }
 
         NBTTagList ench = tag.getList(key.NBT, CraftMagicNumbers.NBT.TAG_COMPOUND);
-        Map<Enchantment, Integer> enchantments = new HashMap<Enchantment, Integer>(ench.size());
+        EnchantmentMap enchantments = new EnchantmentMap(); // Paper
 
         for (int i = 0; i < ench.size(); i++) {
             int id = 0xffff & ((NBTTagCompound) ench.get(i)).getShort(ENCHANTMENTS_ID.NBT);
@@ -546,13 +549,13 @@ class CraftMetaItem implements ItemMeta, Repairable {
     void deserializeInternal(NBTTagCompound tag) {
     }
 
-    static Map<Enchantment, Integer> buildEnchantments(Map<String, Object> map, ItemMetaKey key) {
+    static EnchantmentMap buildEnchantments(Map<String, Object> map, ItemMetaKey key) { // Paper
         Map<?, ?> ench = SerializableMeta.getObject(Map.class, map, key.BUKKIT, true);
         if (ench == null) {
             return null;
         }
 
-        Map<Enchantment, Integer> enchantments = new HashMap<Enchantment, Integer>(ench.size());
+        EnchantmentMap enchantments = new EnchantmentMap(); // Paper
         for (Map.Entry<?, ?> entry : ench.entrySet()) {
             // Doctor older enchants
             String enchantKey = entry.getKey().toString();
@@ -703,13 +706,13 @@ class CraftMetaItem implements ItemMeta, Repairable {
     }
 
     public Map<Enchantment, Integer> getEnchants() {
-        return hasEnchants() ? ImmutableMap.copyOf(enchantments) : ImmutableMap.<Enchantment, Integer>of();
+        return hasEnchants() ? ImmutableSortedMap.copyOfSorted(enchantments) : ImmutableMap.<Enchantment, Integer>of(); // Paper
     }
 
     public boolean addEnchant(Enchantment ench, int level, boolean ignoreRestrictions) {
         Validate.notNull(ench, "Enchantment cannot be null");
         if (enchantments == null) {
-            enchantments = new HashMap<Enchantment, Integer>(4);
+            enchantments = new EnchantmentMap(); // Paper
         }
 
         if (ignoreRestrictions || level >= ench.getStartLevel() && level <= ench.getMaxLevel()) {
@@ -880,7 +883,7 @@ class CraftMetaItem implements ItemMeta, Repairable {
                 clone.lore = new ArrayList<String>(this.lore);
             }
             if (this.enchantments != null) {
-                clone.enchantments = new HashMap<Enchantment, Integer>(this.enchantments);
+                clone.enchantments = new EnchantmentMap(this.enchantments); // Paper
             }
             clone.hideFlag = this.hideFlag;
             clone.unbreakable = this.unbreakable;
@@ -1038,6 +1041,23 @@ class CraftMetaItem implements ItemMeta, Repairable {
         }
     }
 
+    // Paper start
+    private static class EnchantmentMap extends TreeMap<Enchantment, Integer> {
+        private EnchantmentMap(Map<Enchantment, Integer> enchantments) {
+            this();
+            putAll(enchantments);
+        }
+
+        private EnchantmentMap() {
+            super((o1, o2) -> ((Integer) o1.getId()).compareTo(o2.getId()));
+        }
+
+        public EnchantmentMap clone() {
+            return (EnchantmentMap) super.clone();
+        }
+    }
+    // Paper end
+
     // Spigot start
     private final Spigot spigot = new Spigot()
     {
-- 
2.18.0