From 38e8105d867922d1514b97a856f7c7a89a6de931 Mon Sep 17 00:00:00 2001
From: Sam Kirby <sam.kirby94@hotmail.co.uk>
Date: Mon, 18 Nov 2019 11:09:48 +0000
Subject: [PATCH] Create MixinPacketBuffer

As a result of this change, the integer item ID is sent (as variable length integer) instead of truncating to a short.

Closes #106
---
 src/main/java/org/dimdev/jeid/JEID.java       |  2 -
 .../jeid/mixin/core/MixinPacketBuffer.java    | 55 +++++++++++++++++++
 src/main/resources/mixins.jeid.core.json      |  3 +-
 3 files changed, 57 insertions(+), 3 deletions(-)
 create mode 100644 src/main/java/org/dimdev/jeid/mixin/core/MixinPacketBuffer.java

diff --git a/src/main/java/org/dimdev/jeid/JEID.java b/src/main/java/org/dimdev/jeid/JEID.java
index 8f73556..05bbf1d 100644
--- a/src/main/java/org/dimdev/jeid/JEID.java
+++ b/src/main/java/org/dimdev/jeid/JEID.java
@@ -51,7 +51,6 @@ public void onPreInit(FMLPreInitializationEvent event) {
             for (int i = 0; i < 5000; i++) {
                 Block block = new Block(Material.GROUND)
                         .setCreativeTab(CreativeTabs.BUILDING_BLOCKS)
-                        .setRegistryName("block_" + i)
                         .setRegistryName(new ResourceLocation("jeid:block_" + i));
 
                 blockRegistry.register(block);
@@ -64,7 +63,6 @@ public void onPreInit(FMLPreInitializationEvent event) {
             for (int i = 0; i < 40000; i++) {
                 Item item = new Item()
                         .setCreativeTab(CreativeTabs.FOOD)
-                        .setRegistryName("item_" + i)
                         .setRegistryName(new ResourceLocation("jeid:item_" + i));
 
                 itemRegistry.register(item);
diff --git a/src/main/java/org/dimdev/jeid/mixin/core/MixinPacketBuffer.java b/src/main/java/org/dimdev/jeid/mixin/core/MixinPacketBuffer.java
new file mode 100644
index 0000000..27332ff
--- /dev/null
+++ b/src/main/java/org/dimdev/jeid/mixin/core/MixinPacketBuffer.java
@@ -0,0 +1,55 @@
+package org.dimdev.jeid.mixin.core;
+
+import io.netty.buffer.ByteBuf;
+import net.minecraft.item.Item;
+import net.minecraft.item.ItemStack;
+import net.minecraft.nbt.NBTTagCompound;
+import net.minecraft.network.PacketBuffer;
+import org.spongepowered.asm.mixin.Mixin;
+import org.spongepowered.asm.mixin.Shadow;
+import org.spongepowered.asm.mixin.injection.At;
+import org.spongepowered.asm.mixin.injection.Inject;
+import org.spongepowered.asm.mixin.injection.Redirect;
+import org.spongepowered.asm.mixin.injection.callback.CallbackInfoReturnable;
+
+import javax.annotation.Nullable;
+import java.io.IOException;
+
+@Mixin(PacketBuffer.class)
+public abstract class MixinPacketBuffer {
+    @Shadow public abstract byte readByte();
+
+    @Shadow public abstract short readShort();
+
+    @Shadow public abstract int readVarInt();
+
+    @Shadow @Nullable public abstract NBTTagCompound readCompoundTag() throws IOException;
+
+    @Shadow public abstract PacketBuffer writeVarInt(int input);
+
+    @Redirect(method = "writeItemStack", at = @At(value = "INVOKE", target = "Lnet/minecraft/network/PacketBuffer;writeShort(I)Lio/netty/buffer/ByteBuf;", ordinal = 0))
+    private ByteBuf writeIntItemId(PacketBuffer packetBuffer, int p_writeShort_1_) {
+        return this.writeVarInt(p_writeShort_1_);
+    }
+
+    @Redirect(method = "writeItemStack", at = @At(value = "INVOKE", target = "Lnet/minecraft/network/PacketBuffer;writeShort(I)Lio/netty/buffer/ByteBuf;", ordinal = 1))
+    private ByteBuf writeIntItemId1(PacketBuffer packetBuffer, int p_writeShort_1_) {
+        return this.writeVarInt(p_writeShort_1_);
+    }
+
+
+    @Inject(method = "readItemStack", at = @At(value = "HEAD"), cancellable = true)
+    private void readIntItemId(CallbackInfoReturnable<ItemStack> cir) throws IOException {
+        int i = this.readVarInt();
+
+        if (i < 0) {
+            cir.setReturnValue(ItemStack.EMPTY);
+        } else {
+            int j = this.readByte();
+            int k = this.readShort();
+            ItemStack itemstack = new ItemStack(Item.getItemById(i), j, k);
+            itemstack.getItem().readNBTShareTag(itemstack, this.readCompoundTag());
+            cir.setReturnValue(itemstack);
+        }
+    }
+}
diff --git a/src/main/resources/mixins.jeid.core.json b/src/main/resources/mixins.jeid.core.json
index 7c042d4..55eb89c 100644
--- a/src/main/resources/mixins.jeid.core.json
+++ b/src/main/resources/mixins.jeid.core.json
@@ -18,7 +18,8 @@
     "MixinChunkProviderServer",
     "MixinWorldInfo",
     "MixinEnchantmentHelper",
-    "MixinItemEnchantedBook"
+    "MixinItemEnchantedBook",
+    "MixinPacketBuffer"
   ],
   "client": [
     "client.MixinChunk",