From 1dab50ca003abc59e4115a329bcb46f76c105e15 Mon Sep 17 00:00:00 2001
From: LexManos <LexManos@gmail.com>
Date: Mon, 10 Aug 2026 21:56:47 -0700
Subject: [PATCH] Fix mod packets being processed after vanilla packets when
 received in the same tick.

---
 .../net/minecraftforge/common/ForgeHooks.java | 31 +++++++++++++++++++
 .../common/util/LogicalSidedProvider.java     |  2 ++
 .../network/simple/SimpleFlow.java            |  2 +-
 3 files changed, 34 insertions(+), 1 deletion(-)

diff --git a/src/main/java/net/minecraftforge/common/ForgeHooks.java b/src/main/java/net/minecraftforge/common/ForgeHooks.java
index e44f8c4a8c..0a988ce2c3 100644
--- a/src/main/java/net/minecraftforge/common/ForgeHooks.java
+++ b/src/main/java/net/minecraftforge/common/ForgeHooks.java
@@ -15,6 +15,7 @@ import java.util.List;
 import java.util.Map;
 import java.util.Objects;
 import java.util.Optional;
+import java.util.function.BiConsumer;
 import java.util.function.Function;
 import java.util.function.Predicate;
 import java.util.regex.Matcher;
@@ -54,6 +55,7 @@ import net.minecraft.core.particles.ParticleTypes;
 import net.minecraft.core.registries.Registries;
 import net.minecraft.network.Connection;
 import net.minecraft.network.FriendlyByteBuf;
+import net.minecraft.network.PacketListener;
 import net.minecraft.network.RegistryFriendlyByteBuf;
 import net.minecraft.network.VarInt;
 import net.minecraft.network.chat.ClickEvent;
@@ -107,6 +109,7 @@ import net.minecraft.nbt.CompoundTag;
 import net.minecraft.nbt.ListTag;
 import net.minecraft.network.protocol.Packet;
 import net.minecraft.network.protocol.PacketFlow;
+import net.minecraft.network.protocol.PacketType;
 import net.minecraft.network.protocol.common.custom.CustomPacketPayload;
 import net.minecraft.network.protocol.common.custom.DiscardedPayload;
 import net.minecraft.network.syncher.EntityDataSerializer;
@@ -1305,4 +1308,32 @@ public final class ForgeHooks {
 
         return Optional.of(ret);
     }
+
+    // This is similar to PacketUtils.ensureRunningOnSameThread, we can't use the normal LogicalSidedProvider.WORKQUEUE because it is processed after packets.
+    // So any vanilla packets that are received after this packet, will be processed before our enqueued packet.
+    public static <MSG> void enqueuePacket(BiConsumer<MSG, CustomPayloadEvent.Context> handler, MSG packet, CustomPayloadEvent.Context context) {
+        var processor = LogicalSidedProvider.PACKETS.get(context.isClientSide());
+        if (!processor.isSameThread())
+            processor.scheduleIfPossible(context.getConnection().getPacketListener(), new DummyPacket<>(handler, packet, context));
+        else
+            handler.accept(packet, context);
+    }
+
+    private static final record DummyPacket<MSG>(
+        BiConsumer<MSG, CustomPayloadEvent.Context> handler,
+        MSG packet,
+        CustomPayloadEvent.Context context
+    ) implements Packet<PacketListener> {
+        private static final PacketType<DummyPacket<?>> TYPE = new PacketType<>(PacketFlow.CLIENTBOUND, Identifier.fromNamespaceAndPath("forge", "dummy_for_schedualing"));
+
+        @Override
+        public PacketType<DummyPacket<?>> type() {
+            return TYPE;
+        }
+
+        @Override
+        public void handle(PacketListener listener) {
+            handler.accept(packet, context);
+        }
+    }
 }
\ No newline at end of file
diff --git a/src/main/java/net/minecraftforge/common/util/LogicalSidedProvider.java b/src/main/java/net/minecraftforge/common/util/LogicalSidedProvider.java
index 8020174ac0..02a725ac34 100644
--- a/src/main/java/net/minecraftforge/common/util/LogicalSidedProvider.java
+++ b/src/main/java/net/minecraftforge/common/util/LogicalSidedProvider.java
@@ -6,6 +6,7 @@
 package net.minecraftforge.common.util;
 
 import net.minecraft.client.Minecraft;
+import net.minecraft.network.PacketProcessor;
 import net.minecraft.server.MinecraftServer;
 import net.minecraft.server.TickTask;
 import net.minecraft.util.thread.BlockableEventLoop;
@@ -21,6 +22,7 @@ import org.jetbrains.annotations.ApiStatus;
 public class LogicalSidedProvider<T> {
     public static final LogicalSidedProvider<BlockableEventLoop<? super TickTask>> WORKQUEUE = new LogicalSidedProvider<>(Supplier::get, Supplier::get);
     public static final LogicalSidedProvider<Optional<Level>> CLIENTWORLD = new LogicalSidedProvider<>((c)-> Optional.of(c.get().level), (s)->Optional.empty());
+    public static final LogicalSidedProvider<PacketProcessor> PACKETS = new LogicalSidedProvider<>(client -> client.get().packetProcessor(), server -> server.get().packetProcessor());
 
     public T get(LogicalSide side) {
         return side == LogicalSide.CLIENT ? clientSide.apply(client) : serverSide.apply(server);
diff --git a/src/main/java/net/minecraftforge/network/simple/SimpleFlow.java b/src/main/java/net/minecraftforge/network/simple/SimpleFlow.java
index bd9f3a5b1e..c1906d1633 100644
--- a/src/main/java/net/minecraftforge/network/simple/SimpleFlow.java
+++ b/src/main/java/net/minecraftforge/network/simple/SimpleFlow.java
@@ -28,7 +28,7 @@ public interface SimpleFlow<BUF extends FriendlyByteBuf, BASE> extends SimplePro
      */
     default <MSG extends BASE> SimpleFlow<BUF, BASE> addMain(Class<MSG> type, StreamCodec<BUF, MSG> codec, BiConsumer<MSG, CustomPayloadEvent.Context> handler) {
         return add(type, codec, (msg, ctx) -> {
-            ctx.enqueueWork(() -> handler.accept(msg, ctx));
+            net.minecraftforge.common.ForgeHooks.enqueuePacket(handler, msg, ctx);
             ctx.setPacketHandled(true);
         });
     }