PaperMC/Remapped-Spigot-Server-Patches/0432-Add-Raw-Byte-ItemStack-Serialization.patch

From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Mariell Hoversholm <proximyst@proximyst.com>
Date: Thu, 30 Apr 2020 16:56:54 +0200
Subject: [PATCH] Add Raw Byte ItemStack Serialization

Serializes using NBT which is safer for server data migrations than bukkits format.

diff --git a/src/main/java/net/minecraft/nbt/NbtIo.java b/src/main/java/net/minecraft/nbt/NbtIo.java
index b3838e709c1581c25da7738c9a03a827761845b1..05ace1d046e32a261e67bff5afc18c2d32e1a8aa 100644
--- a/src/main/java/net/minecraft/nbt/NbtIo.java
+++ b/src/main/java/net/minecraft/nbt/NbtIo.java
@@ -51,6 +51,7 @@ public class NbtIo {
         return nbttagcompound;
     }
 
+    public static CompoundTag readNBT(InputStream inputstream) throws IOException { return readCompressed(inputstream); } // Paper - OBFHELPER
     public static CompoundTag readCompressed(InputStream stream) throws IOException {
         DataInputStream datainputstream = new DataInputStream(new BufferedInputStream(new GZIPInputStream(stream)));
         Throwable throwable = null;
@@ -106,6 +107,7 @@ public class NbtIo {
 
     }
 
+    public static void writeNBT(CompoundTag nbttagcompound, OutputStream outputstream) throws IOException { writeCompressed(nbttagcompound, outputstream); } // Paper - OBFHELPER
     public static void writeCompressed(CompoundTag tag, OutputStream stream) throws IOException {
         DataOutputStream dataoutputstream = new DataOutputStream(new BufferedOutputStream(new GZIPOutputStream(stream)));
         Throwable throwable = null;
diff --git a/src/main/java/net/minecraft/util/datafix/DataFixers.java b/src/main/java/net/minecraft/util/datafix/DataFixers.java
index 950a4b67f9091af551ec1036ebeb943e3b335e91..dc4e2fc26e1bc2c545f955d30c052bb86e3ef614 100644
--- a/src/main/java/net/minecraft/util/datafix/DataFixers.java
+++ b/src/main/java/net/minecraft/util/datafix/DataFixers.java
@@ -78,6 +78,7 @@ public class DataFixers {
         return datafixerbuilder.build(Util.bootstrapExecutor());
     }
 
+    public static DataFixer getDataFixer() { return getDataFixer(); } // Paper - OBFHELPER
     public static DataFixer getDataFixer() {
         return DataFixers.DATA_FIXER;
     }
diff --git a/src/main/java/net/minecraft/world/item/ItemStack.java b/src/main/java/net/minecraft/world/item/ItemStack.java
index ac996d581925c8f92832009945c766962e5b51c5..458cdfbeac9d757c9721acd4557a548affa0ede1 100644
--- a/src/main/java/net/minecraft/world/item/ItemStack.java
+++ b/src/main/java/net/minecraft/world/item/ItemStack.java
@@ -196,6 +196,7 @@ public final class ItemStack {
         this.updateEmptyCacheFlag();
     }
 
+    public static ItemStack fromCompound(CompoundTag nbttagcompound) { return of(nbttagcompound); } // Paper - OBFHELPER
     public static ItemStack of(CompoundTag tag) {
         try {
             return new ItemStack(tag);
diff --git a/src/main/java/org/bukkit/craftbukkit/util/CraftMagicNumbers.java b/src/main/java/org/bukkit/craftbukkit/util/CraftMagicNumbers.java
index 86b319337fc41a09dd45df466df60cadaed1343f..a5a5038a84434e69fda8f6b41d2f00b4989e25ae 100644
--- a/src/main/java/org/bukkit/craftbukkit/util/CraftMagicNumbers.java
+++ b/src/main/java/org/bukkit/craftbukkit/util/CraftMagicNumbers.java
@@ -378,6 +378,46 @@ public final class CraftMagicNumbers implements UnsafeValues {
     public boolean isSupportedApiVersion(String apiVersion) {
         return apiVersion != null && SUPPORTED_API.contains(apiVersion);
     }
+
+    @Override
+    public byte[] serializeItem(ItemStack item) {
+        Preconditions.checkNotNull(item, "null cannot be serialized");
+        Preconditions.checkArgument(item.getType() != Material.AIR, "air cannot be serialized");
+
+        java.io.ByteArrayOutputStream outputStream = new java.io.ByteArrayOutputStream();
+        CompoundTag compound = (item instanceof CraftItemStack ? ((CraftItemStack) item).getHandle() : CraftItemStack.asNMSCopy(item)).save(new CompoundTag());
+        compound.putInt("DataVersion", getDataVersion());
+        try {
+            net.minecraft.nbt.NbtIo.writeNBT(
+                compound,
+                outputStream
+            );
+        } catch (IOException ex) {
+            throw new RuntimeException(ex);
+        }
+
+        return outputStream.toByteArray();
+    }
+
+    @Override
+    public ItemStack deserializeItem(byte[] data) {
+        Preconditions.checkNotNull(data, "null cannot be deserialized");
+        Preconditions.checkArgument(data.length > 0, "cannot deserialize nothing");
+
+        try {
+            CompoundTag compound = net.minecraft.nbt.NbtIo.readNBT(
+                new java.io.ByteArrayInputStream(data)
+            );
+            int dataVersion = compound.getInt("DataVersion");
+
+            Preconditions.checkArgument(dataVersion <= getDataVersion(), "Newer version! Server downgrades are not supported!");
+            Dynamic<Tag> converted = DataFixers.getDataFixer().update(References.ITEM_STACK, new Dynamic<Tag>(NbtOps.INSTANCE, compound), dataVersion, getDataVersion());
+            return CraftItemStack.asCraftMirror(net.minecraft.world.item.ItemStack.fromCompound((CompoundTag) converted.getValue()));
+        } catch (IOException ex) {
+            com.destroystokyo.paper.util.SneakyThrow.sneaky(ex);
+            throw new RuntimeException();
+        }
+    }
     // Paper end
 
     /**