Let Minecraft handle packet decoding during recording

We've done this ourselves only because it was easier at the beginning.
However with 1.20.5, Minecraft's packet decoding became substantially
more sophisticated, to the point that it's probably a bad idea to try
to do it ourselves.

Additionally, getting the packet ids, which we require for identifying
the packets which we want to decode, has becomes significantly more
difficult too, and this way it's a simple instanceof check.

src/main/java/com/replaymod/recording/packet/PacketListener.java

@@ -73,7 +73,6 @@ import java.util.concurrent.atomic.AtomicInteger;
 
 import static com.replaymod.core.versions.MCVer.*;
 import static com.replaymod.replaystudio.util.Utils.writeInt;
-import static java.util.Objects.requireNonNull;
 
 //#if MC>=11904
 //$$ import net.minecraft.network.PacketBundleHandler;
@@ -92,28 +91,6 @@ public class PacketListener extends ChannelInboundHandlerAdapter {
     private static final MinecraftClient mc = getMinecraft();
     private static final Logger logger = LogManager.getLogger();
 
-    private static final ResourcePackSendS2CPacket RESOURCE_PACK_SEND_PACKET =
-            //#if MC>=12003
-            //$$ new ResourcePackSendS2CPacket(null, "", "", false, null)
-            //#elseif MC>=11700
-            //$$ new ResourcePackSendS2CPacket("", "", false, null)
-            //#else
-            new ResourcePackSendS2CPacket()
-            //#endif
-            ;
-    private static final int PACKET_ID_RESOURCE_PACK_SEND = getPacketId(NetworkState.PLAY, RESOURCE_PACK_SEND_PACKET);
-    //#if MC>=12002
-    //$$ private static final int PACKET_ID_CONFIG_RESOURCE_PACK_SEND = getPacketId(NetworkState.CONFIGURATION, RESOURCE_PACK_SEND_PACKET);
-    //#endif
-    //#if MC>=11700
-    //$$ private static final int PACKET_ID_LOGIN_COMPRESSION = getPacketId(NetworkState.LOGIN, new LoginCompressionS2CPacket(0));
-    //#else
-    private static final int PACKET_ID_LOGIN_COMPRESSION = getPacketId(NetworkState.LOGIN, new LoginCompressionS2CPacket());
-    //#endif
-    //#if MC<10904
-    //$$ private static final int PACKET_ID_PLAY_COMPRESSION = getPacketId(EnumConnectionState.PLAY, new S46PacketSetCompressionLevel());
-    //#endif
-
     private final ReplayMod core;
     private final Path outputPath;
     private final ReplayFile replayFile;
@@ -126,6 +103,7 @@ public class PacketListener extends ChannelInboundHandlerAdapter {
     private ReplayMetaData metaData;
 
     private ChannelHandlerContext context = null;
+    private Packet currentRawPacket;
 
     private final long startTime;
     private long lastSentPacket;
@@ -199,17 +177,6 @@ public class PacketListener extends ChannelInboundHandlerAdapter {
             return;
         }
         try {
-            //#if MC>=11800
-            if (packet.getRegistry().getState() == State.LOGIN && packet.getId() == PACKET_ID_LOGIN_COMPRESSION) {
-                return; // Replay data is never compressed on the packet level
-            }
-            //#if MC<10904
-            //$$ if (packet.getRegistry().getState() == State.PLAY && packet.getId() == PACKET_ID_PLAY_COMPRESSION) {
-            //$$     return; // Replay data is never compressed on the packet level
-            //$$ }
-            //#endif
-            //#endif
-
             long now = System.currentTimeMillis();
             if (serverWasPaused) {
                 timePassedWhilePaused = now - startTime - lastSentPacket;
@@ -388,24 +355,15 @@ public class PacketListener extends ChannelInboundHandlerAdapter {
             //#endif
         }
 
-        if (packet != null) {
+        currentRawPacket = packet;
-            if (connectionState == NetworkState.PLAY && packet.getId() == PACKET_ID_RESOURCE_PACK_SEND
+        try {
-                    //#if MC>=12002
+            super.channelRead(ctx, msg);
-                    //$$ || connectionState == NetworkState.CONFIGURATION && packet.getId() == PACKET_ID_CONFIG_RESOURCE_PACK_SEND
+        } finally {
-                    //#endif
+            if (currentRawPacket != null) {
-            ) {
+                currentRawPacket.release();
-                ClientConnection connection = ctx.pipeline().get(ClientConnection.class);
+                currentRawPacket = null;
-                save(resourcePackRecorder.handleResourcePack(connection, (ResourcePackSendS2CPacket) decodeMcPacket(packet)));
-                //#if MC>=12003
-                //$$ super.channelRead(ctx, msg);
-                //#endif
-                return;
             }
-
-            save(packet);
         }
-
-        super.channelRead(ctx, msg);
     }
 
     private NetworkState getConnectionState() {
@@ -448,26 +406,6 @@ public class PacketListener extends ChannelInboundHandlerAdapter {
         }
     }
 
-    private static net.minecraft.network.Packet decodeMcPacket(Packet packet) throws IOException, IllegalAccessException, InstantiationException {
-        NetworkState connectionState = asMc(packet.getRegistry().getState());
-        int packetId = packet.getId();
-        PacketByteBuf packetBuf = new PacketByteBuf(Unpooled.wrappedBuffer(packet.getBuf().nioBuffer()));
-
-        //#if MC>=12002
-        //$$ return connectionState.getHandler(NetworkSide.CLIENTBOUND).createPacket(packetId, packetBuf);
-        //#elseif MC>=11700
-        //$$ return connectionState.getPacketHandler(NetworkSide.CLIENTBOUND, packetId, packetBuf);
-        //#else
-        //#if MC>=10800
-        net.minecraft.network.Packet p = connectionState.getPacketHandler(NetworkSide.CLIENTBOUND, packetId);
-        //#else
-        //$$ net.minecraft.network.Packet p = net.minecraft.network.Packet.generatePacket(connectionState.func_150755_b(), packetId);
-        //#endif
-        p.read(packetBuf);
-        return p;
-        //#endif
-    }
-
     private static Packet decodePacket(NetworkState connectionState, ByteBuf buf) {
         PacketByteBuf packetBuf = new PacketByteBuf(buf.slice());
         int packetId = packetBuf.readVarInt();
@@ -480,14 +418,6 @@ public class PacketListener extends ChannelInboundHandlerAdapter {
         );
     }
 
-    private static int getPacketId(NetworkState networkState, net.minecraft.network.Packet packet) {
-        try {
-            return requireNonNull(networkState.getPacketId(NetworkSide.CLIENTBOUND, packet));
-        } catch (Exception e) {
-            throw new RuntimeException("Failed to determine packet id for " + packet.getClass(), e);
-        }
-    }
-
     public void addMarker(String name) {
         addMarker(name, (int) getCurrentDuration());
     }
@@ -535,6 +465,17 @@ public class PacketListener extends ChannelInboundHandlerAdapter {
         @Override
         public void channelRead(ChannelHandlerContext ctx, Object msg) throws Exception {
 
+            if (msg instanceof LoginCompressionS2CPacket) {
+                super.channelRead(ctx, msg);
+                return;
+            }
+            //#if MC<10904
+            //$$ if (msg instanceof S46PacketSetCompressionLevel) {
+            //$$     super.channelRead(ctx, msg);
+            //$$     return;
+            //$$ }
+            //#endif
+
             if (msg instanceof CustomPayloadS2CPacket) {
                 CustomPayloadS2CPacket packet = (CustomPayloadS2CPacket) msg;
                 if (Restrictions.PLUGIN_CHANNEL.equals(packet.getChannel())) {
@@ -559,6 +500,20 @@ public class PacketListener extends ChannelInboundHandlerAdapter {
                 saveMetaData();
             }
 
+            if (msg instanceof ResourcePackSendS2CPacket) {
+                ClientConnection connection = ctx.pipeline().get(ClientConnection.class);
+                save(resourcePackRecorder.handleResourcePack(connection, (ResourcePackSendS2CPacket) msg));
+                //#if MC>=12003
+                //$$ super.channelRead(ctx, msg);
+                //#endif
+                return;
+            }
+
+            if (currentRawPacket != null) {
+                save(currentRawPacket);
+                currentRawPacket = null;
+            }
+
             super.channelRead(ctx, msg);
         }
     }