More absolutely cursed WIP

api/src/main/java/com/viaversion/viaversion/api/type/Type.java

@@ -179,7 +179,7 @@ public abstract class Type<T> implements ByteBufReader<T>, ByteBufWriter<T> {
     public static final Type<Item[]> FLAT_VAR_INT_ITEM_ARRAY_VAR_INT = new ArrayType<>(FLAT_VAR_INT_ITEM);
 
     public static final Type<Item> ITEM1_20_2 = new Item1_20_2Type();
-    public static final Type<Item[]> ITEM1_20_2_ARRAY_VAR_INT = new ArrayType<>(ITEM1_20_2);
+    public static final Type<Item[]> ITEM1_20_2_VAR_INT_ARRAY = new ArrayType<>(ITEM1_20_2);
 
     /* Actual Class */
     private final Class<? super T> outputClass;

common/src/main/java/com/viaversion/viaversion/protocol/ProtocolManagerImpl.java

@@ -83,6 +83,9 @@ import it.unimi.dsi.fastutil.ints.Int2ObjectLinkedOpenHashMap;
 import it.unimi.dsi.fastutil.ints.Int2ObjectMap;
 import it.unimi.dsi.fastutil.ints.Int2ObjectOpenHashMap;
 import it.unimi.dsi.fastutil.ints.Int2ObjectSortedMap;
+import org.checkerframework.checker.nullness.qual.Nullable;
+import us.myles.ViaVersion.api.protocol.ProtocolRegistry;
+
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collection;
@@ -103,8 +106,6 @@ import java.util.concurrent.TimeUnit;
 import java.util.concurrent.locks.ReadWriteLock;
 import java.util.concurrent.locks.ReentrantReadWriteLock;
 import java.util.function.Function;
-import org.checkerframework.checker.nullness.qual.Nullable;
-import us.myles.ViaVersion.api.protocol.ProtocolRegistry;
 
 public class ProtocolManagerImpl implements ProtocolManager {
     private static final Protocol BASE_PROTOCOL = new BaseProtocol();
@@ -135,7 +136,7 @@ public class ProtocolManagerImpl implements ProtocolManager {
         // Base Protocol
         registerBaseProtocol(BASE_PROTOCOL, Range.lessThan(Integer.MIN_VALUE));
         registerBaseProtocol(new BaseProtocol1_7(), Range.lessThan(ProtocolVersion.v1_16.getVersion()));
-        registerBaseProtocol(new BaseProtocol1_16(), Range.atLeast(ProtocolVersion.v1_16.getVersion()));
+        registerBaseProtocol(new BaseProtocol1_16(), Range.closed(ProtocolVersion.v1_16.getVersion(), ProtocolVersion.v1_20.getVersion()));
 
         registerProtocol(new Protocol1_9To1_8(), ProtocolVersion.v1_9, ProtocolVersion.v1_8);
         registerProtocol(new Protocol1_9_1To1_9(), Arrays.asList(ProtocolVersion.v1_9_1.getVersion(), ProtocolVersion.v1_9_2.getVersion()), ProtocolVersion.v1_9.getVersion());

common/src/main/java/com/viaversion/viaversion/protocols/base/BaseProtocol1_16.java

@@ -19,15 +19,11 @@ package com.viaversion.viaversion.protocols.base;
 
 import com.viaversion.viaversion.api.protocol.packet.PacketWrapper;
 import com.viaversion.viaversion.api.type.Type;
+
 import java.util.UUID;
 
 public class BaseProtocol1_16 extends BaseProtocol1_7 {
 
-    @Override
-    protected boolean finishLoginAfterGameprofile() {
-        return false; // Start CONFIGURATION phase after the serverbound ack
-    }
-
     @Override
     protected UUID passthroughLoginUUID(final PacketWrapper wrapper) throws Exception {
         return wrapper.passthrough(Type.UUID);

common/src/main/java/com/viaversion/viaversion/protocols/base/BaseProtocol1_7.java

@@ -121,7 +121,7 @@ public class BaseProtocol1_7 extends AbstractProtocol {
         // Login Success Packet
         registerClientbound(ClientboundLoginPackets.GAME_PROFILE, wrapper -> {
             ProtocolInfo info = wrapper.user().getProtocolInfo();
-            if (finishLoginAfterGameprofile()) {
+            if (info.getProtocolVersion() < ProtocolVersion.v1_20_2.getVersion()) {
                 info.setState(State.PLAY);
             }
 
@@ -166,8 +166,6 @@ public class BaseProtocol1_7 extends AbstractProtocol {
         });
 
         registerServerbound(ServerboundLoginPackets.LOGIN_ACKNOWLEDGED, wrapper -> wrapper.user().getProtocolInfo().setState(State.CONFIGURATION));
-        // TODO AAAAAAAAAAAAAAAAA
-        registerServerbound(ServerboundConfigurationPackets1_20_2.FINISH_CONFIGURATION, wrapper -> wrapper.user().getProtocolInfo().setState(State.PLAY));
     }
 
     @Override
@@ -192,8 +190,4 @@ public class BaseProtocol1_7 extends AbstractProtocol {
         }
         return UUID.fromString(uuidString);
     }
-
-    protected boolean finishLoginAfterGameprofile() {
-        return true;
-    }
 }

common/src/main/java/com/viaversion/viaversion/protocols/base/ServerboundLoginPackets.java

@@ -23,9 +23,8 @@ import com.viaversion.viaversion.api.protocol.packet.State;
 public enum ServerboundLoginPackets implements ServerboundPacketType {
     HELLO, // 0x00
     ENCRYPTION_KEY, // 0x01
-    CUSTOM_QUERY, // 0x02
+    CUSTOM_QUERY_ANSWER, // 0x02
-    CUSTOM_QUERY_ANSWER, // 0x03
+    LOGIN_ACKNOWLEDGED; // 0x03
-    LOGIN_ACKNOWLEDGED; // 0x04
 
     @Override
     public final int getId() {

common/src/main/java/com/viaversion/viaversion/protocols/protocol1_19_3to1_19_1/rewriter/RecipeRewriter1_19_3.java

@@ -48,7 +48,7 @@ public class RecipeRewriter1_19_3<C extends ClientboundPacketType> extends Recip
         wrapper.passthrough(Type.STRING); // Group
         wrapper.passthrough(Type.VAR_INT); // Crafting book category
         handleIngredients(wrapper);
-        rewrite(wrapper.passthrough(Type.FLAT_VAR_INT_ITEM)); // Result
+        rewrite(wrapper.passthrough(itemType())); // Result
     }
 
     @Override
@@ -59,7 +59,7 @@ public class RecipeRewriter1_19_3<C extends ClientboundPacketType> extends Recip
         for (int i = 0; i < ingredients; i++) {
             handleIngredient(wrapper);
         }
-        rewrite(wrapper.passthrough(Type.FLAT_VAR_INT_ITEM)); // Result
+        rewrite(wrapper.passthrough(itemType())); // Result
     }
 
     @Override
@@ -67,7 +67,7 @@ public class RecipeRewriter1_19_3<C extends ClientboundPacketType> extends Recip
         wrapper.passthrough(Type.STRING); // Group
         wrapper.passthrough(Type.VAR_INT); // Crafting book category
         handleIngredient(wrapper);
-        rewrite(wrapper.passthrough(Type.FLAT_VAR_INT_ITEM)); // Result
+        rewrite(wrapper.passthrough(itemType())); // Result
         wrapper.passthrough(Type.FLOAT); // EXP
         wrapper.passthrough(Type.VAR_INT); // Cooking time
     }

common/src/main/java/com/viaversion/viaversion/protocols/protocol1_20_2to1_20/Protocol1_20_2To1_20.java

@@ -28,19 +28,24 @@ import com.viaversion.viaversion.api.rewriter.EntityRewriter;
 import com.viaversion.viaversion.api.rewriter.ItemRewriter;
 import com.viaversion.viaversion.api.type.Type;
 import com.viaversion.viaversion.data.entity.EntityTrackerBase;
+import com.viaversion.viaversion.exception.CancelException;
+import com.viaversion.viaversion.protocol.packet.PacketWrapperImpl;
+import com.viaversion.viaversion.protocols.base.ClientboundLoginPackets;
 import com.viaversion.viaversion.protocols.base.ServerboundLoginPackets;
 import com.viaversion.viaversion.protocols.protocol1_19_4to1_19_3.ClientboundPackets1_19_4;
 import com.viaversion.viaversion.protocols.protocol1_19_4to1_19_3.ServerboundPackets1_19_4;
-import com.viaversion.viaversion.protocols.protocol1_20_2to1_20.rewriter.BlockItemPacketRewriter1_20_2;
-import com.viaversion.viaversion.protocols.protocol1_20_2to1_20.rewriter.EntityPacketRewriter1_20_2;
 import com.viaversion.viaversion.protocols.protocol1_20_2to1_20.packet.ClientboundConfigurationPackets1_20_2;
 import com.viaversion.viaversion.protocols.protocol1_20_2to1_20.packet.ClientboundPackets1_20_2;
 import com.viaversion.viaversion.protocols.protocol1_20_2to1_20.packet.ServerboundConfigurationPackets1_20_2;
 import com.viaversion.viaversion.protocols.protocol1_20_2to1_20.packet.ServerboundPackets1_20_2;
+import com.viaversion.viaversion.protocols.protocol1_20_2to1_20.rewriter.BlockItemPacketRewriter1_20_2;
+import com.viaversion.viaversion.protocols.protocol1_20_2to1_20.rewriter.EntityPacketRewriter1_20_2;
 import com.viaversion.viaversion.protocols.protocol1_20_2to1_20.storage.FakeProtocolState;
 import com.viaversion.viaversion.rewriter.SoundRewriter;
 import com.viaversion.viaversion.rewriter.StatisticsRewriter;
 import com.viaversion.viaversion.rewriter.TagRewriter;
+import io.netty.buffer.ByteBuf;
+import io.netty.buffer.ByteBufAllocator;
 import org.checkerframework.checker.nullness.qual.Nullable;
 
 import java.util.UUID;
@@ -57,8 +62,6 @@ public final class Protocol1_20_2To1_20 extends AbstractProtocol<ClientboundPack
 
     @Override
     protected void registerPackets() {
-        // TODO Updated NBT type used in: block entity, chunk, tag query, entity metadata data, item type, mob effect
-
         // TODO Handle Enabled features and tags before configuration phase end
         // TODO Make sure Paper/Velocity handle a 0,0 uuid fine during login
 
@@ -89,16 +92,31 @@ public final class Protocol1_20_2To1_20 extends AbstractProtocol<ClientboundPack
         });
 
         // Deal with the new CONFIGURATION protocol state the client expects
+        registerClientbound(State.LOGIN, ClientboundLoginPackets.GAME_PROFILE.getId(), ClientboundLoginPackets.GAME_PROFILE.getId(), wrapper -> {
+            wrapper.user().get(FakeProtocolState.class).setGameProfileSent(true);
+        });
+
         registerServerbound(State.LOGIN, ServerboundLoginPackets.LOGIN_ACKNOWLEDGED.getId(), -1, wrapper -> {
+            System.out.println("Login acknowleged!");
+            wrapper.user().getProtocolInfo().setState(State.PLAY);
             wrapper.user().get(FakeProtocolState.class).setConfigurationState(true);
             wrapper.cancel();
         });
+        cancelServerbound(State.LOGIN, ServerboundLoginPackets.CUSTOM_QUERY_ANSWER.getId()); // TODO ?
 
+        // TODO Make sure this is called in other protocols as well/the base protocol
         registerServerbound(State.CONFIGURATION, ServerboundConfigurationPackets1_20_2.FINISH_CONFIGURATION.getId(), -1, wrapper -> {
             wrapper.user().get(FakeProtocolState.class).setConfigurationState(false);
+            System.out.println("NOW PLAYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYY");
             wrapper.cancel();
         });
-        registerServerbound(State.CONFIGURATION, ServerboundConfigurationPackets1_20_2.CUSTOM_PAYLOAD.getId(), ServerboundPackets1_19_4.PLUGIN_MESSAGE.getId(), wrapper -> {
+        registerServerbound(State.CONFIGURATION, ServerboundConfigurationPackets1_20_2.CUSTOM_PAYLOAD.getId(), -1, wrapper -> {
+            if (wrapper.user().getProtocolInfo().getState() == State.PLAY) {
+                wrapper.setPacketType(ServerboundPackets1_19_4.PLUGIN_MESSAGE);
+            } else {
+                wrapper.user().get(FakeProtocolState.class).addPacketToQueue(wrapper, false);
+                wrapper.cancel();
+            }
         });
         registerServerbound(State.CONFIGURATION, ServerboundConfigurationPackets1_20_2.KEEP_ALIVE.getId(), ServerboundPackets1_19_4.KEEP_ALIVE.getId(), wrapper -> {
         });
@@ -120,25 +138,24 @@ public final class Protocol1_20_2To1_20 extends AbstractProtocol<ClientboundPack
     }
 
     @Override
-    public void transform(Direction direction, State state, PacketWrapper packetWrapper) throws Exception {
+    public void transform(final Direction direction, final State state, final PacketWrapper packetWrapper) throws Exception {
-        final boolean configurationState = packetWrapper.user().get(FakeProtocolState.class).isConfigurationState();
+        final FakeProtocolState fakeProtocolState = packetWrapper.user().get(FakeProtocolState.class);
-        if (direction == Direction.SERVERBOUND) {
+        if (fakeProtocolState.hasGameProfileBeenSent() && !fakeProtocolState.isConfigurationState()) {
-            // Redirect packets during the fake configuration phase
+            fakeProtocolState.addPacketToQueue(packetWrapper, direction == Direction.CLIENTBOUND);
-            // This might mess up people using Via API/other protocols down the line, but such is life. We can't have different states for server and client
+            System.out.println("added to queue " + packetWrapper.getId() + " " + direction + " " + state);
-            final State newState = configurationState ? State.CONFIGURATION : state;
+            super.transform(direction, State.PLAY, packetWrapper);
-            super.transform(direction, newState, packetWrapper);
+            throw CancelException.generate();
-            return;
         }
 
-        // Make sure we don't send the client any packets from another protocol state
+        System.out.println("Transforming " + packetWrapper.getId() + " " + direction + " " + state);
-        if (configurationState) {
+        System.out.println(fakeProtocolState.isConfigurationState());
-            // TODO Queue these packets to send them later
+        if (!fakeProtocolState.isConfigurationState()) {
-            Via.getPlatform().getLogger().warning("Cancelled packet " + packetWrapper.getId() + " sent during configuration state");
-            packetWrapper.cancel();
             super.transform(direction, state, packetWrapper);
             return;
         }
 
+        if (direction == Direction.CLIENTBOUND
+                && (packetWrapper.getPacketType() == null || packetWrapper.getPacketType().state() != State.CONFIGURATION)) {
             // Map some of them to their configuration state counterparts
             final int unmappedId = packetWrapper.getId();
             if (state == State.PLAY && unmappedId != ClientboundPackets1_19_4.JOIN_GAME.getId()) {
@@ -156,11 +173,20 @@ public final class Protocol1_20_2To1_20 extends AbstractProtocol<ClientboundPack
                     packetWrapper.setPacketType(ClientboundConfigurationPackets1_20_2.UPDATE_ENABLED_FEATURES);
                 } else if (unmappedId == ClientboundPackets1_19_4.TAGS.getId()) {
                     packetWrapper.setPacketType(ClientboundConfigurationPackets1_20_2.UPDATE_TAGS);
-            }
+                } else {
+                    // TODO Queue these packets to send them later
+                    Via.getPlatform().getLogger().warning("Cancelled packet " + packetWrapper.getId() + " sent during configuration state");
+                    packetWrapper.cancel();
                     return;
                 }
 
-        super.transform(direction, state, packetWrapper);
+                super.transform(direction, State.CONFIGURATION, packetWrapper);
+            }
+        } else {
+            // Redirect packets during the fake configuration phase
+            // This might mess up people using Via API/other protocols down the line, but such is life. We can't have different states for server and client
+            super.transform(direction, State.CONFIGURATION, packetWrapper);
+        }
     }
 
     @Override

common/src/main/java/com/viaversion/viaversion/protocols/protocol1_20_2to1_20/rewriter/BlockItemPacketRewriter1_20_2.java

@@ -17,17 +17,28 @@
  */
 package com.viaversion.viaversion.protocols.protocol1_20_2to1_20.rewriter;
 
+import com.viaversion.viaversion.api.data.ParticleMappings;
+import com.viaversion.viaversion.api.data.entity.EntityTracker;
+import com.viaversion.viaversion.api.minecraft.chunks.Chunk;
+import com.viaversion.viaversion.api.minecraft.item.Item;
 import com.viaversion.viaversion.api.minecraft.metadata.ChunkPosition;
+import com.viaversion.viaversion.api.protocol.packet.PacketWrapper;
+import com.viaversion.viaversion.api.protocol.remapper.PacketHandlers;
 import com.viaversion.viaversion.api.type.Type;
+import com.viaversion.viaversion.protocols.protocol1_18to1_17_1.types.Chunk1_18Type;
 import com.viaversion.viaversion.protocols.protocol1_19_4to1_19_3.ClientboundPackets1_19_4;
+import com.viaversion.viaversion.protocols.protocol1_19_4to1_19_3.rewriter.RecipeRewriter1_19_4;
 import com.viaversion.viaversion.protocols.protocol1_20_2to1_20.Protocol1_20_2To1_20;
 import com.viaversion.viaversion.protocols.protocol1_20_2to1_20.packet.ServerboundPackets1_20_2;
+import com.viaversion.viaversion.protocols.protocol1_20_2to1_20.types.Chunk1_20_2Type;
+import com.viaversion.viaversion.protocols.protocol1_20to1_19_4.Protocol1_20To1_19_4;
 import com.viaversion.viaversion.rewriter.ItemRewriter;
+import com.viaversion.viaversion.util.MathUtil;
 
 public final class BlockItemPacketRewriter1_20_2 extends ItemRewriter<ClientboundPackets1_19_4, ServerboundPackets1_20_2, Protocol1_20_2To1_20> {
 
     public BlockItemPacketRewriter1_20_2(final Protocol1_20_2To1_20 protocol) {
-        super(protocol);
+        super(protocol, Type.ITEM1_20_2, Type.ITEM1_20_2_VAR_INT_ARRAY);
     }
 
     @Override
@@ -37,5 +48,250 @@ public final class BlockItemPacketRewriter1_20_2 extends ItemRewriter<Clientboun
             final int z = wrapper.read(Type.INT);
             wrapper.write(Type.CHUNK_POSITION, new ChunkPosition(x, z));
         });
+
+        protocol.registerClientbound(ClientboundPackets1_19_4.NBT_QUERY, wrapper -> {
+            wrapper.passthrough(Type.VAR_INT); // Transaction id
+            wrapper.write(Type.NAMELESS_NBT, wrapper.read(Type.NBT));
+        });
+
+        protocol.registerClientbound(ClientboundPackets1_19_4.BLOCK_ENTITY_DATA, wrapper -> {
+            wrapper.passthrough(Type.POSITION1_14); // Position
+            wrapper.passthrough(Type.VAR_INT); // Type
+            wrapper.write(Type.NAMELESS_NBT, wrapper.read(Type.NBT));
+        });
+
+        protocol.registerClientbound(ClientboundPackets1_19_4.CHUNK_DATA, wrapper -> {
+            final EntityTracker tracker = protocol.getEntityRewriter().tracker(wrapper.user());
+            final Type<Chunk> chunkType = new Chunk1_18Type(tracker.currentWorldSectionHeight(),
+                    MathUtil.ceilLog2(Protocol1_20To1_19_4.MAPPINGS.getBlockStateMappings().mappedSize()),
+                    MathUtil.ceilLog2(tracker.biomesSent()));
+            final Chunk chunk = wrapper.read(chunkType);
+
+            final Type<Chunk> newChunkType = new Chunk1_20_2Type(tracker.currentWorldSectionHeight(),
+                    MathUtil.ceilLog2(Protocol1_20To1_19_4.MAPPINGS.getBlockStateMappings().mappedSize()),
+                    MathUtil.ceilLog2(tracker.biomesSent()));
+            wrapper.write(newChunkType, chunk);
+        });
+
+        // Weeeeeeeeeeeeeeeeeeeeeeeeeeeeee
+        protocol.registerClientbound(ClientboundPackets1_19_4.WINDOW_ITEMS, new PacketHandlers() {
+            @Override
+            public void register() {
+                map(Type.UNSIGNED_BYTE); // Window id
+                map(Type.VAR_INT); // State id
+                handler(wrapper -> {
+                    wrapper.write(Type.ITEM1_20_2_VAR_INT_ARRAY, wrapper.read(Type.FLAT_ITEM_ARRAY_VAR_INT)); // Items
+                    wrapper.write(Type.ITEM1_20_2, wrapper.read(Type.FLAT_VAR_INT_ITEM)); // Carried item
+                });
+            }
+        });
+        protocol.registerClientbound(ClientboundPackets1_19_4.SET_SLOT, new PacketHandlers() {
+            @Override
+            public void register() {
+                map(Type.UNSIGNED_BYTE); // Window id
+                map(Type.VAR_INT); // State id
+                map(Type.SHORT); // Slot id
+                map(Type.FLAT_VAR_INT_ITEM, Type.ITEM1_20_2); // Item
+            }
+        });
+        protocol.registerClientbound(ClientboundPackets1_19_4.ADVANCEMENTS, wrapper -> {
+            wrapper.passthrough(Type.BOOLEAN); // Reset/clear
+            int size = wrapper.passthrough(Type.VAR_INT); // Mapping size
+            for (int i = 0; i < size; i++) {
+                wrapper.passthrough(Type.STRING); // Identifier
+
+                // Parent
+                if (wrapper.passthrough(Type.BOOLEAN))
+                    wrapper.passthrough(Type.STRING);
+
+                // Display data
+                if (wrapper.passthrough(Type.BOOLEAN)) {
+                    wrapper.passthrough(Type.COMPONENT); // Title
+                    wrapper.passthrough(Type.COMPONENT); // Description
+                    wrapper.write(Type.ITEM1_20_2, wrapper.read(Type.FLAT_VAR_INT_ITEM)); // Icon
+                    wrapper.passthrough(Type.VAR_INT); // Frame type
+                    int flags = wrapper.passthrough(Type.INT); // Flags
+                    if ((flags & 1) != 0) {
+                        wrapper.passthrough(Type.STRING); // Background texture
+                    }
+                    wrapper.passthrough(Type.FLOAT); // X
+                    wrapper.passthrough(Type.FLOAT); // Y
+                }
+
+                wrapper.passthrough(Type.STRING_ARRAY); // Criteria
+
+                int arrayLength = wrapper.passthrough(Type.VAR_INT);
+                for (int array = 0; array < arrayLength; array++) {
+                    wrapper.passthrough(Type.STRING_ARRAY); // String array
+                }
+
+                wrapper.passthrough(Type.BOOLEAN); // Send telemetry
+            }
+        });
+        protocol.registerClientbound(ClientboundPackets1_19_4.ENTITY_EQUIPMENT, new PacketHandlers() {
+            @Override
+            public void register() {
+                map(Type.VAR_INT); // 0 - Entity ID
+                handler(wrapper -> {
+                    byte slot;
+                    do {
+                        slot = wrapper.passthrough(Type.BYTE);
+                        wrapper.write(Type.ITEM1_20_2, wrapper.read(Type.FLAT_VAR_INT_ITEM));
+                    } while ((slot & 0xFFFFFF80) != 0);
+                });
+            }
+        });
+        protocol.registerServerbound(ServerboundPackets1_20_2.CLICK_WINDOW, new PacketHandlers() {
+            @Override
+            public void register() {
+                map(Type.UNSIGNED_BYTE); // Window Id
+                map(Type.VAR_INT); // State id
+                map(Type.SHORT); // Slot
+                map(Type.BYTE); // Button
+                map(Type.VAR_INT); // Mode
+
+                handler(wrapper -> {
+                    // Affected items
+                    int length = wrapper.passthrough(Type.VAR_INT);
+                    for (int i = 0; i < length; i++) {
+                        wrapper.passthrough(Type.SHORT); // Slot
+                        wrapper.write(Type.FLAT_VAR_INT_ITEM, wrapper.read(Type.ITEM1_20_2));
+                    }
+
+                    // Carried item
+                    wrapper.write(Type.FLAT_VAR_INT_ITEM, wrapper.read(Type.ITEM1_20_2));
+                });
+            }
+        });
+        protocol.registerClientbound(ClientboundPackets1_19_4.TRADE_LIST, wrapper -> {
+            wrapper.passthrough(Type.VAR_INT); // Container id
+            int size = wrapper.passthrough(Type.VAR_INT);
+            for (int i = 0; i < size; i++) {
+                wrapper.write(Type.ITEM1_20_2, wrapper.read(Type.FLAT_VAR_INT_ITEM)); // Input
+                wrapper.write(Type.ITEM1_20_2, wrapper.read(Type.FLAT_VAR_INT_ITEM)); // Output
+                wrapper.write(Type.ITEM1_20_2, wrapper.read(Type.FLAT_VAR_INT_ITEM)); // Second Item
+
+                wrapper.passthrough(Type.BOOLEAN); // Trade disabled
+                wrapper.passthrough(Type.INT); // Number of tools uses
+                wrapper.passthrough(Type.INT); // Maximum number of trade uses
+
+                wrapper.passthrough(Type.INT); // XP
+                wrapper.passthrough(Type.INT); // Special price
+                wrapper.passthrough(Type.FLOAT); // Price multiplier
+                wrapper.passthrough(Type.INT); // Demand
+            }
+        });
+        protocol.registerServerbound(ServerboundPackets1_20_2.CREATIVE_INVENTORY_ACTION, new PacketHandlers() {
+            @Override
+            public void register() {
+                map(Type.SHORT); // 0 - Slot
+                map(Type.ITEM1_20_2, Type.FLAT_VAR_INT_ITEM); // 1 - Clicked Item
+            }
+        });
+        protocol.registerClientbound(ClientboundPackets1_19_4.SPAWN_PARTICLE, new PacketHandlers() {
+            @Override
+            public void register() {
+                map(Type.VAR_INT); // 0 - Particle ID
+                map(Type.BOOLEAN); // 1 - Long Distance
+                map(Type.DOUBLE); // 2 - X
+                map(Type.DOUBLE); // 3 - Y
+                map(Type.DOUBLE); // 4 - Z
+                map(Type.FLOAT); // 5 - Offset X
+                map(Type.FLOAT); // 6 - Offset Y
+                map(Type.FLOAT); // 7 - Offset Z
+                map(Type.FLOAT); // 8 - Particle Data
+                map(Type.INT); // 9 - Particle Count
+                handler(wrapper -> {
+                    int id = wrapper.get(Type.VAR_INT, 0);
+                    ParticleMappings mappings = Protocol1_20To1_19_4.MAPPINGS.getParticleMappings();
+                    if (mappings.isItemParticle(id)) {
+                        wrapper.write(Type.ITEM1_20_2, wrapper.read(Type.FLAT_VAR_INT_ITEM));
+                    }
+                });
+            }
+        });
+
+        new RecipeRewriter1_19_4<ClientboundPackets1_19_4>(protocol) {
+            @Override
+            public void handleCraftingShapeless(final PacketWrapper wrapper) throws Exception {
+                wrapper.passthrough(Type.STRING); // Group
+                wrapper.passthrough(Type.VAR_INT); // Crafting book category
+                handleIngredients(wrapper);
+
+                final Item result = wrapper.read(itemType());
+                rewrite(result);
+                wrapper.write(Type.ITEM1_20_2, result);
+            }
+
+            @Override
+            public void handleSmelting(final PacketWrapper wrapper) throws Exception {
+                wrapper.passthrough(Type.STRING); // Group
+                wrapper.passthrough(Type.VAR_INT); // Crafting book category
+                handleIngredient(wrapper);
+
+                final Item result = wrapper.read(itemType());
+                rewrite(result);
+                wrapper.write(Type.ITEM1_20_2, result);
+
+                wrapper.passthrough(Type.FLOAT); // EXP
+                wrapper.passthrough(Type.VAR_INT); // Cooking time
+            }
+
+            @Override
+            public void handleCraftingShaped(final PacketWrapper wrapper) throws Exception {
+                final int ingredients = wrapper.passthrough(Type.VAR_INT) * wrapper.passthrough(Type.VAR_INT);
+                wrapper.passthrough(Type.STRING); // Group
+                wrapper.passthrough(Type.VAR_INT); // Crafting book category
+                for (int i = 0; i < ingredients; i++) {
+                    handleIngredient(wrapper);
+                }
+
+                final Item result = wrapper.read(itemType());
+                rewrite(result);
+                wrapper.write(Type.ITEM1_20_2, result);
+
+                wrapper.passthrough(Type.BOOLEAN); // Show notification
+            }
+
+            @Override
+            public void handleStonecutting(final PacketWrapper wrapper) throws Exception {
+                wrapper.passthrough(Type.STRING); // Group
+                handleIngredient(wrapper);
+
+                final Item result = wrapper.read(itemType());
+                rewrite(result);
+                wrapper.write(Type.ITEM1_20_2, result);
+            }
+
+            @Override
+            public void handleSmithing(final PacketWrapper wrapper) throws Exception {
+                handleIngredient(wrapper); // Base
+                handleIngredient(wrapper); // Addition
+
+                final Item result = wrapper.read(itemType());
+                rewrite(result);
+                wrapper.write(Type.ITEM1_20_2, result);
+            }
+
+            @Override
+            public void handleSmithingTransform(final PacketWrapper wrapper) throws Exception {
+                handleIngredient(wrapper); // Template
+                handleIngredient(wrapper); // Base
+                handleIngredient(wrapper); // Additions
+
+                final Item result = wrapper.read(itemType());
+                rewrite(result);
+                wrapper.write(Type.ITEM1_20_2, result);
+            }
+
+            @Override
+            protected void handleIngredient(final PacketWrapper wrapper) throws Exception {
+                final Item[] items = wrapper.read(itemArrayType());
+                wrapper.write(Type.ITEM1_20_2_VAR_INT_ARRAY, items);
+                for (final Item item : items) {
+                    rewrite(item);
+                }
+            }
+        }.register(ClientboundPackets1_19_4.DECLARE_RECIPES);
     }
 }

common/src/main/java/com/viaversion/viaversion/protocols/protocol1_20_2to1_20/rewriter/EntityPacketRewriter1_20_2.java

@@ -18,11 +18,10 @@
 package com.viaversion.viaversion.protocols.protocol1_20_2to1_20.rewriter;
 
 import com.github.steveice10.opennbt.tag.builtin.CompoundTag;
-import com.viaversion.viaversion.api.connection.UserConnection;
 import com.viaversion.viaversion.api.minecraft.entities.Entity1_19_4Types;
 import com.viaversion.viaversion.api.minecraft.entities.EntityType;
-import com.viaversion.viaversion.api.minecraft.metadata.Metadata;
 import com.viaversion.viaversion.api.protocol.packet.PacketWrapper;
+import com.viaversion.viaversion.api.protocol.packet.State;
 import com.viaversion.viaversion.api.protocol.remapper.PacketHandlers;
 import com.viaversion.viaversion.api.type.Type;
 import com.viaversion.viaversion.api.type.types.version.Types1_20;
@@ -32,8 +31,6 @@ import com.viaversion.viaversion.protocols.protocol1_20_2to1_20.Protocol1_20_2To
 import com.viaversion.viaversion.protocols.protocol1_20_2to1_20.packet.ClientboundConfigurationPackets1_20_2;
 import com.viaversion.viaversion.rewriter.EntityRewriter;
 
-import java.util.List;
-
 public final class EntityPacketRewriter1_20_2 extends EntityRewriter<ClientboundPackets1_19_4, Protocol1_20_2To1_20> {
 
     public EntityPacketRewriter1_20_2(final Protocol1_20_2To1_20 protocol) {
@@ -95,6 +92,11 @@ public final class EntityPacketRewriter1_20_2 extends EntityRewriter<Clientbound
                     enableFeaturesPacket.write(Type.STRING, "minecraft:vanilla");
                     enableFeaturesPacket.scheduleSend(Protocol1_20_2To1_20.class);
 
+                    final PacketWrapper finishConfigurationPacket = wrapper.create(ClientboundConfigurationPackets1_20_2.FINISH_CONFIGURATION);
+                    finishConfigurationPacket.send(Protocol1_20_2To1_20.class);
+
+                    System.out.println("PLEASEEEEEEEE");
+
                     // Manually send it at the end and hope nothing breaks
                     wrapper.send(Protocol1_20_2To1_20.class);
                     wrapper.cancel();
@@ -126,6 +128,17 @@ public final class EntityPacketRewriter1_20_2 extends EntityRewriter<Clientbound
                 handler(worldDataTrackerHandlerByKey()); // Tracks world height and name for chunk data and entity (un)tracking
             }
         });
+
+        protocol.registerClientbound(ClientboundPackets1_19_4.ENTITY_EFFECT, wrapper -> {
+            wrapper.passthrough(Type.VAR_INT); // Entity id
+            wrapper.passthrough(Type.VAR_INT); // Effect id
+            wrapper.passthrough(Type.BYTE); // Amplifier
+            wrapper.passthrough(Type.VAR_INT); // Duration
+            wrapper.passthrough(Type.BYTE); // Flags
+            if (wrapper.passthrough(Type.BOOLEAN)) {
+                wrapper.write(Type.NAMELESS_NBT, wrapper.read(Type.NBT)); // Factor data
+            }
+        });
     }
 
     @Override

common/src/main/java/com/viaversion/viaversion/protocols/protocol1_20_2to1_20/rewriter/RecipeRewriter1_20_2.java

@@ -0,0 +1,41 @@
+/*
+ * This file is part of ViaVersion - https://github.com/ViaVersion/ViaVersion
+ * Copyright (C) 2023 ViaVersion and contributors
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+package com.viaversion.viaversion.protocols.protocol1_20_2to1_20.rewriter;
+
+import com.viaversion.viaversion.api.minecraft.item.Item;
+import com.viaversion.viaversion.api.protocol.Protocol;
+import com.viaversion.viaversion.api.protocol.packet.ClientboundPacketType;
+import com.viaversion.viaversion.api.type.Type;
+import com.viaversion.viaversion.protocols.protocol1_19_4to1_19_3.rewriter.RecipeRewriter1_19_4;
+
+public class RecipeRewriter1_20_2<C extends ClientboundPacketType> extends RecipeRewriter1_19_4<C> {
+
+    public RecipeRewriter1_20_2(final Protocol<C, ?, ?, ?> protocol) {
+        super(protocol);
+    }
+
+    @Override
+    protected Type<Item> itemType() {
+        return Type.ITEM1_20_2;
+    }
+
+    @Override
+    protected Type<Item[]> itemArrayType() {
+        return Type.ITEM1_20_2_VAR_INT_ARRAY;
+    }
+}

common/src/main/java/com/viaversion/viaversion/protocols/protocol1_20_2to1_20/storage/FakeProtocolState.java

@@ -18,10 +18,18 @@
 package com.viaversion.viaversion.protocols.protocol1_20_2to1_20.storage;
 
 import com.viaversion.viaversion.api.connection.StorableObject;
+import com.viaversion.viaversion.api.protocol.packet.PacketWrapper;
+import com.viaversion.viaversion.protocol.packet.PacketWrapperImpl;
+import io.netty.buffer.ByteBuf;
+
+import java.util.ArrayList;
+import java.util.List;
 
 public class FakeProtocolState implements StorableObject {
 
+    private final List<QueuedPacket> packetQueue = new ArrayList<>();
     private boolean configurationState;
+    private boolean gameProfileSent;
 
     public boolean isConfigurationState() {
         return configurationState;
@@ -31,8 +39,42 @@ public class FakeProtocolState implements StorableObject {
         this.configurationState = configurationState;
     }
 
+    public void addPacketToQueue(final PacketWrapper wrapper, final boolean clientbound) {
+        packetQueue.add(new QueuedPacket(((PacketWrapperImpl) wrapper).getInputBuffer().copy(), clientbound)); // TODO
+    }
+
+    public List<QueuedPacket> packetQueue() {
+        return packetQueue;
+    }
+
+    public boolean hasGameProfileBeenSent() {
+        return gameProfileSent;
+    }
+
+    public void setGameProfileSent(final boolean gameProfileSent) {
+        this.gameProfileSent = gameProfileSent;
+    }
+
     @Override
     public boolean clearOnServerSwitch() {
         return false;
     }
+
+    public static final class QueuedPacket {
+        private final ByteBuf buf;
+        private final boolean clientbound;
+
+        private QueuedPacket(final ByteBuf buf, final boolean clientbound) {
+            this.buf = buf;
+            this.clientbound = clientbound;
+        }
+
+        public ByteBuf buf() {
+            return buf;
+        }
+
+        public boolean clientbound() {
+            return clientbound;
+        }
+    }
 }

common/src/main/java/com/viaversion/viaversion/protocols/protocol1_20_2to1_20/types/Chunk1_20_2Type.java

@@ -0,0 +1,102 @@
+/*
+ * This file is part of ViaVersion - https://github.com/ViaVersion/ViaVersion
+ * Copyright (C) 2016-2023 ViaVersion and contributors
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+package com.viaversion.viaversion.protocols.protocol1_20_2to1_20.types;
+
+import com.github.steveice10.opennbt.tag.builtin.CompoundTag;
+import com.google.common.base.Preconditions;
+import com.viaversion.viaversion.api.Via;
+import com.viaversion.viaversion.api.minecraft.blockentity.BlockEntity;
+import com.viaversion.viaversion.api.minecraft.chunks.Chunk;
+import com.viaversion.viaversion.api.minecraft.chunks.Chunk1_18;
+import com.viaversion.viaversion.api.minecraft.chunks.ChunkSection;
+import com.viaversion.viaversion.api.type.Type;
+import com.viaversion.viaversion.api.type.types.minecraft.BaseChunkType;
+import com.viaversion.viaversion.api.type.types.version.ChunkSectionType1_18;
+import com.viaversion.viaversion.api.type.types.version.Types1_18;
+import io.netty.buffer.ByteBuf;
+
+import java.util.ArrayList;
+import java.util.List;
+
+public final class Chunk1_20_2Type extends Type<Chunk> {
+    private final ChunkSectionType1_18 sectionType;
+    private final int ySectionCount;
+
+    public Chunk1_20_2Type(final int ySectionCount, final int globalPaletteBlockBits, final int globalPaletteBiomeBits) {
+        super(Chunk.class);
+        Preconditions.checkArgument(ySectionCount > 0);
+        this.sectionType = new ChunkSectionType1_18(globalPaletteBlockBits, globalPaletteBiomeBits);
+        this.ySectionCount = ySectionCount;
+    }
+
+    @Override
+    public Chunk read(final ByteBuf buffer) throws Exception {
+        final int chunkX = buffer.readInt();
+        final int chunkZ = buffer.readInt();
+        final CompoundTag heightMap = Type.NAMELESS_NBT.read(buffer);
+
+        // Read sections
+        final ByteBuf sectionsBuf = buffer.readBytes(Type.VAR_INT.readPrimitive(buffer));
+        final ChunkSection[] sections = new ChunkSection[ySectionCount];
+        try {
+            for (int i = 0; i < ySectionCount; i++) {
+                sections[i] = sectionType.read(sectionsBuf);
+            }
+        } finally {
+            sectionsBuf.release();
+        }
+
+        final int blockEntitiesLength = Type.VAR_INT.readPrimitive(buffer);
+        final List<BlockEntity> blockEntities = new ArrayList<>(blockEntitiesLength);
+        for (int i = 0; i < blockEntitiesLength; i++) {
+            blockEntities.add(Types1_18.BLOCK_ENTITY.read(buffer));
+        }
+
+        return new Chunk1_18(chunkX, chunkZ, sections, heightMap, blockEntities);
+    }
+
+    @Override
+    public void write(final ByteBuf buffer, final Chunk chunk) throws Exception {
+        buffer.writeInt(chunk.getX());
+        buffer.writeInt(chunk.getZ());
+
+        Type.NAMELESS_NBT.write(buffer, chunk.getHeightMap());
+
+        final ByteBuf sectionBuffer = buffer.alloc().buffer();
+        try {
+            for (final ChunkSection section : chunk.getSections()) {
+                sectionType.write(sectionBuffer, section);
+            }
+            sectionBuffer.readerIndex(0);
+            Type.VAR_INT.writePrimitive(buffer, sectionBuffer.readableBytes());
+            buffer.writeBytes(sectionBuffer);
+        } finally {
+            sectionBuffer.release(); // release buffer
+        }
+
+        Type.VAR_INT.writePrimitive(buffer, chunk.blockEntities().size());
+        for (final BlockEntity blockEntity : chunk.blockEntities()) {
+            Types1_18.BLOCK_ENTITY.write(buffer, blockEntity);
+        }
+    }
+
+    @Override
+    public Class<? extends Type> getBaseClass() {
+        return BaseChunkType.class;
+    }
+}

common/src/main/java/com/viaversion/viaversion/rewriter/BlockRewriter.java

@@ -42,10 +42,16 @@ import org.checkerframework.checker.nullness.qual.Nullable;
 public class BlockRewriter<C extends ClientboundPacketType> {
     private final Protocol<C, ?, ?, ?> protocol;
     private final Type<Position> positionType;
+    private final Type<CompoundTag> nbtType;
 
     public BlockRewriter(Protocol<C, ?, ?, ?> protocol, Type<Position> positionType) {
+        this(protocol, positionType, Type.NBT);
+    }
+
+    public BlockRewriter(Protocol<C, ?, ?, ?> protocol, Type<Position> positionType, Type<CompoundTag> nbtType) {
         this.protocol = protocol;
         this.positionType = positionType;
+        this.nbtType = nbtType;
     }
 
     public void registerBlockAction(C packetType) {
@@ -203,7 +209,7 @@ public class BlockRewriter<C extends ClientboundPacketType> {
 
     public void registerBlockEntityData(C packetType, @Nullable Consumer<BlockEntity> blockEntityHandler) {
         protocol.registerClientbound(packetType, wrapper -> {
-            final Position position = wrapper.passthrough(Type.POSITION1_14);
+            final Position position = wrapper.passthrough(positionType);
 
             final int blockEntityId = wrapper.read(Type.VAR_INT);
             final Mappings mappings = protocol.getMappingData().getBlockEntityMappings();
@@ -214,7 +220,7 @@ public class BlockRewriter<C extends ClientboundPacketType> {
             }
 
             final CompoundTag tag;
-            if (blockEntityHandler != null && (tag = wrapper.passthrough(Type.NBT)) != null) {
+            if (blockEntityHandler != null && (tag = wrapper.passthrough(nbtType)) != null) {
                 final BlockEntity blockEntity = new BlockEntityImpl(BlockEntity.pack(position.x(), position.z()), (short) position.y(), blockEntityId, tag);
                 blockEntityHandler.accept(blockEntity);
             }

common/src/main/java/com/viaversion/viaversion/rewriter/ItemRewriter.java

@@ -31,9 +31,17 @@ import org.checkerframework.checker.nullness.qual.Nullable;
 
 public abstract class ItemRewriter<C extends ClientboundPacketType, S extends ServerboundPacketType,
         T extends Protocol<C, ?, ?, S>> extends RewriterBase<T> implements com.viaversion.viaversion.api.rewriter.ItemRewriter<T> {
+    private final Type<Item> itemType;
+    private final Type<Item[]> itemArrayType;
 
     protected ItemRewriter(T protocol) {
+        this(protocol, Type.FLAT_VAR_INT_ITEM, Type.FLAT_VAR_INT_ITEM_ARRAY);
+    }
+
+    public ItemRewriter(T protocol, Type<Item> itemType, Type<Item[]> itemArrayType) {
         super(protocol);
+        this.itemType = itemType;
+        this.itemArrayType = itemArrayType;
     }
 
     // These two methods always return the same item instance *for now*
@@ -74,12 +82,12 @@ public abstract class ItemRewriter<C extends ClientboundPacketType, S extends Se
                 map(Type.UNSIGNED_BYTE); // Window id
                 map(Type.VAR_INT); // State id
                 handler(wrapper -> {
-                    Item[] items = wrapper.passthrough(Type.FLAT_VAR_INT_ITEM_ARRAY_VAR_INT);
+                    Item[] items = wrapper.passthrough(itemArrayType);
                     for (Item item : items) {
                         handleItemToClient(item);
                     }
 
-                    handleItemToClient(wrapper.passthrough(Type.FLAT_VAR_INT_ITEM)); // Carried item
+                    handleItemToClient(wrapper.passthrough(itemType)); // Carried item
                 });
             }
         });
@@ -123,8 +131,8 @@ public abstract class ItemRewriter<C extends ClientboundPacketType, S extends Se
                 map(Type.UNSIGNED_BYTE); // Window id
                 map(Type.VAR_INT); // State id
                 map(Type.SHORT); // Slot id
-                map(Type.FLAT_VAR_INT_ITEM); // Item
+                map(itemType); // Item
-                handler(itemToClientHandler(Type.FLAT_VAR_INT_ITEM));
+                handler(itemToClientHandler(itemType));
             }
         });
     }
@@ -155,7 +163,7 @@ public abstract class ItemRewriter<C extends ClientboundPacketType, S extends Se
                     do {
                         slot = wrapper.passthrough(Type.BYTE);
                         // & 0x7F into an extra variable if slot is needed
-                        handleItemToClient(wrapper.passthrough(Type.FLAT_VAR_INT_ITEM));
+                        handleItemToClient(wrapper.passthrough(itemType));
                     } while ((slot & 0xFFFFFF80) != 0);
                 });
             }
@@ -168,7 +176,6 @@ public abstract class ItemRewriter<C extends ClientboundPacketType, S extends Se
             public void register() {
                 map(Type.SHORT); // 0 - Slot
                 map(type); // 1 - Clicked Item
-
                 handler(itemToServerHandler(type));
             }
         });
@@ -205,11 +212,11 @@ public abstract class ItemRewriter<C extends ClientboundPacketType, S extends Se
                     int length = wrapper.passthrough(Type.VAR_INT);
                     for (int i = 0; i < length; i++) {
                         wrapper.passthrough(Type.SHORT); // Slot
-                        handleItemToServer(wrapper.passthrough(Type.FLAT_VAR_INT_ITEM));
+                        handleItemToServer(wrapper.passthrough(itemType));
                     }
 
                     // Carried item
-                    handleItemToServer(wrapper.passthrough(Type.FLAT_VAR_INT_ITEM));
+                    handleItemToServer(wrapper.passthrough(itemType));
                 });
             }
         });
@@ -228,11 +235,11 @@ public abstract class ItemRewriter<C extends ClientboundPacketType, S extends Se
             wrapper.passthrough(Type.VAR_INT);
             int size = wrapper.passthrough(Type.UNSIGNED_BYTE);
             for (int i = 0; i < size; i++) {
-                handleItemToClient(wrapper.passthrough(Type.FLAT_VAR_INT_ITEM)); // Input
+                handleItemToClient(wrapper.passthrough(itemType)); // Input
-                handleItemToClient(wrapper.passthrough(Type.FLAT_VAR_INT_ITEM)); // Output
+                handleItemToClient(wrapper.passthrough(itemType)); // Output
 
                 if (wrapper.passthrough(Type.BOOLEAN)) { // Has second item
-                    handleItemToClient(wrapper.passthrough(Type.FLAT_VAR_INT_ITEM)); // Second Item
+                    handleItemToClient(wrapper.passthrough(itemType)); // Second Item
                 }
 
                 wrapper.passthrough(Type.BOOLEAN); // Trade disabled
@@ -253,9 +260,9 @@ public abstract class ItemRewriter<C extends ClientboundPacketType, S extends Se
             wrapper.passthrough(Type.VAR_INT); // Container id
             int size = wrapper.passthrough(Type.VAR_INT);
             for (int i = 0; i < size; i++) {
-                handleItemToClient(wrapper.passthrough(Type.FLAT_VAR_INT_ITEM)); // Input
+                handleItemToClient(wrapper.passthrough(itemType)); // Input
-                handleItemToClient(wrapper.passthrough(Type.FLAT_VAR_INT_ITEM)); // Output
+                handleItemToClient(wrapper.passthrough(itemType)); // Output
-                handleItemToClient(wrapper.passthrough(Type.FLAT_VAR_INT_ITEM)); // Second Item
+                handleItemToClient(wrapper.passthrough(itemType)); // Second Item
 
                 wrapper.passthrough(Type.BOOLEAN); // Trade disabled
                 wrapper.passthrough(Type.INT); // Number of tools uses
@@ -304,7 +311,7 @@ public abstract class ItemRewriter<C extends ClientboundPacketType, S extends Se
         });
     }
 
-    public void registerAdvancements1_20(C packetType, Type<Item> type) {
+    public void registerAdvancements1_20(C packetType) {
         protocol.registerClientbound(packetType, wrapper -> {
             wrapper.passthrough(Type.BOOLEAN); // Reset/clear
             int size = wrapper.passthrough(Type.VAR_INT); // Mapping size
@@ -319,7 +326,7 @@ public abstract class ItemRewriter<C extends ClientboundPacketType, S extends Se
                 if (wrapper.passthrough(Type.BOOLEAN)) {
                     wrapper.passthrough(Type.COMPONENT); // Title
                     wrapper.passthrough(Type.COMPONENT); // Description
-                    handleItemToClient(wrapper.passthrough(type)); // Icon
+                    handleItemToClient(wrapper.passthrough(itemType)); // Icon
                     wrapper.passthrough(Type.VAR_INT); // Frame type
                     int flags = wrapper.passthrough(Type.INT); // Flags
                     if ((flags & 1) != 0) {
@@ -396,7 +403,7 @@ public abstract class ItemRewriter<C extends ClientboundPacketType, S extends Se
                 map(Type.FLOAT); // 7 - Offset Z
                 map(Type.FLOAT); // 8 - Particle Data
                 map(Type.INT); // 9 - Particle Count
-                handler(getSpawnParticleHandler(Type.VAR_INT, Type.FLAT_VAR_INT_ITEM));
+                handler(getSpawnParticleHandler(Type.VAR_INT, itemType));
             }
         });
     }

common/src/main/java/com/viaversion/viaversion/rewriter/RecipeRewriter.java

@@ -82,19 +82,19 @@ public class RecipeRewriter<C extends ClientboundPacketType> {
         for (int i = 0; i < ingredientsNo; i++) {
             handleIngredient(wrapper);
         }
-        rewrite(wrapper.passthrough(Type.FLAT_VAR_INT_ITEM)); // Result
+        rewrite(wrapper.passthrough(itemType())); // Result
     }
 
     public void handleCraftingShapeless(PacketWrapper wrapper) throws Exception {
         wrapper.passthrough(Type.STRING); // Group
         handleIngredients(wrapper);
-        rewrite(wrapper.passthrough(Type.FLAT_VAR_INT_ITEM)); // Result
+        rewrite(wrapper.passthrough(itemType())); // Result
     }
 
     public void handleSmelting(PacketWrapper wrapper) throws Exception {
         wrapper.passthrough(Type.STRING); // Group
         handleIngredient(wrapper);
-        rewrite(wrapper.passthrough(Type.FLAT_VAR_INT_ITEM)); // Result
+        rewrite(wrapper.passthrough(itemType())); // Result
         wrapper.passthrough(Type.FLOAT); // EXP
         wrapper.passthrough(Type.VAR_INT); // Cooking time
     }
@@ -102,13 +102,13 @@ public class RecipeRewriter<C extends ClientboundPacketType> {
     public void handleStonecutting(PacketWrapper wrapper) throws Exception {
         wrapper.passthrough(Type.STRING); // Group
         handleIngredient(wrapper);
-        rewrite(wrapper.passthrough(Type.FLAT_VAR_INT_ITEM)); // Result
+        rewrite(wrapper.passthrough(itemType())); // Result
     }
 
     public void handleSmithing(PacketWrapper wrapper) throws Exception {
         handleIngredient(wrapper); // Base
         handleIngredient(wrapper); // Addition
-        rewrite(wrapper.passthrough(Type.FLAT_VAR_INT_ITEM)); // Result
+        rewrite(wrapper.passthrough(itemType())); // Result
     }
 
     public void handleSimpleRecipe(final PacketWrapper wrapper) throws Exception {
@@ -119,7 +119,7 @@ public class RecipeRewriter<C extends ClientboundPacketType> {
         handleIngredient(wrapper); // Template
         handleIngredient(wrapper); // Base
         handleIngredient(wrapper); // Additions
-        rewrite(wrapper.passthrough(Type.FLAT_VAR_INT_ITEM)); // Result
+        rewrite(wrapper.passthrough(itemType())); // Result
     }
 
     public void handleSmithingTrim(final PacketWrapper wrapper) throws Exception {
@@ -135,7 +135,7 @@ public class RecipeRewriter<C extends ClientboundPacketType> {
     }
 
     protected void handleIngredient(final PacketWrapper wrapper) throws Exception {
-        final Item[] items = wrapper.passthrough(Type.FLAT_VAR_INT_ITEM_ARRAY_VAR_INT);
+        final Item[] items = wrapper.passthrough(itemArrayType());
         for (final Item item : items) {
             rewrite(item);
         }
@@ -153,4 +153,12 @@ public class RecipeRewriter<C extends ClientboundPacketType> {
 
         void accept(PacketWrapper wrapper) throws Exception;
     }
+
+    protected Type<Item> itemType() {
+        return Type.FLAT_VAR_INT_ITEM;
+    }
+
+    protected Type<Item[]> itemArrayType() {
+        return Type.FLAT_VAR_INT_ITEM_ARRAY_VAR_INT;
+    }
 }