5.0.4 Release

- Inline tag values in 1.21 enchantments
- Fix TagRewriter addTags if the server doesn't send values for a registry
- Send the tags packet in 1.12->1.13 before the play login packet to fix tracking in 1.20->1.20.2

.editorconfig

@@ -2,7 +2,7 @@
 charset = utf-8
 indent_size = 4
 indent_style = space
-insert_final_newline = false
+insert_final_newline = true
 tab_width = 4
 
 [*.java]
@@ -13,4 +13,4 @@ ij_java_generate_final_locals = true
 ij_java_generate_final_parameters = true
 
 [{*.json,*.yml}]
-indent_size = 2
+indent_size = 2

.github/dependabot.yml

@@ -0,0 +1,6 @@
+version: 2
+updates:
+  - package-ecosystem: "github-actions"
+    directory: "/"
+    schedule:
+      interval: "weekly"

.github/workflows/build.yml

@@ -7,13 +7,13 @@ jobs:
     # Only run on PRs if the source branch is on a different repo. We do not need to run everything twice.
     if: ${{ github.event_name != 'pull_request' || github.repository != github.event.pull_request.head.repo.full_name }}
 
-    runs-on: ubuntu-22.04
+    runs-on: ubuntu-24.04
 
     steps:
     - name: Checkout Repository
       uses: actions/checkout@v4
     - name: Validate Gradle Wrapper
-      uses: gradle/actions/wrapper-validation@v3
+      uses: gradle/actions/wrapper-validation@v4
     - name: Set up JDK 17
       uses: actions/setup-java@v4
       with:

.github/workflows/publish.yml

@@ -8,12 +8,12 @@ on:
 jobs:
   publish:
     if: github.repository_owner == 'ViaVersion'
-    runs-on: ubuntu-22.04
+    runs-on: ubuntu-24.04
     steps:
       - name: Checkout Repository
         uses: actions/checkout@v4
       - name: Validate Gradle Wrapper
-        uses: gradle/actions/wrapper-validation@v3
+        uses: gradle/actions/wrapper-validation@v4
       - name: Set up JDK 17
         uses: actions/setup-java@v4
         with:

.github/workflows/update-gradle-wrapper.yml

@@ -0,0 +1,14 @@
+name: Update Gradle Wrapper
+on:
+  workflow_dispatch:
+  schedule:
+    - cron: "0 0 * * 0"
+
+jobs:
+  update-gradle-wrapper:
+    runs-on: ubuntu-24.04
+    steps:
+      - name: Checkout Repository
+        uses: actions/checkout@v4
+      - name: Update Gradle Wrapper
+        uses: gradle-update/update-gradle-wrapper-action@v2

README.md

@@ -1,7 +1,7 @@
 # ViaVersion
 
 [![Latest Release](https://img.shields.io/github/v/release/ViaVersion/ViaVersion)](https://viaversion.com)
-[![Build Status](https://github.com/ViaVersion/ViaVersion/actions/workflows/gradle.yml/badge.svg?branch=master)](https://github.com/ViaVersion/ViaVersion/actions)
+[![Build Status](https://github.com/ViaVersion/ViaVersion/actions/workflows/build.yml/badge.svg?branch=master)](https://github.com/ViaVersion/ViaVersion/actions)
 [![Discord](https://img.shields.io/badge/chat-on%20discord-blue.svg)](https://viaversion.com/discord)
 
 **Allows the connection of higher client versions to lower server versions -
@@ -9,14 +9,14 @@ it works on any platform you can think of.**
 
 The base ViaVersion jar runs on Paper and Velocity. We also have projects integrating ViaVersion to run
 on Fabric, Forge, Bungee, Sponge, or as a standalone proxy to join from basically any client version on
-any server version from the past decade. **See [HERE](https://github.com/ViaVersion) for an overview of the different Via\* projects.**
+any server version from the past decade. **See [HERE](https://viaversion.com) for an overview of the different Via\* projects.**
 
-Note that ViaVersion will be able to **run best on either Paper servers or Fabric clients** due to having
+Note that ViaVersion will be able to **run best on either Paper servers or through [ViaFabricPlus](https://github.com/ViaVersion/ViaFabricPlus?tab=readme-ov-file#viafabricplus)** due to having
 direct access to client/server state and more extensive API.
 
 Supported Versions:
 
-![Table (https://i.imgur.com/sTrVnC2.png)](https://i.imgur.com/sTrVnC2.png)
+![Table (https://i.imgur.com/zrQTcf0.png)](https://i.imgur.com/zrQTcf0.png)
 
 **User Docs:** https://docs.viaversion.com/display/VIAVERSION/
 
@@ -83,7 +83,7 @@ You need JDK 17 or newer to build ViaVersion.
 
 Mapping Files
 --------------
-Mapping files are generated and managed in our [Mappings repository](https://github.com/ViaVersion/Mappings).
+Mapping files are generated and managed in our [Mappings repository](https://github.com/ViaVersion/Mappings). The generated mapping output is stored [here](./common/src/main/resources/assets/viaversion).
 
 
 Resources
@@ -96,7 +96,7 @@ Resources
 
 License
 --------
-The entirety of the [API directory](api) (including the legacy API directory) is licensed under the MIT License;
+The entirety of the [API directory](api) is licensed under the MIT License;
 see [licenses/MIT.md](licenses/MIT.md) for
 details.
 

api/build.gradle.kts

@@ -24,8 +24,8 @@ dependencies {
         exclude("com.google.code.gson", "gson")
         exclude("com.viaversion", "nbt")
     }
+    api(libs.snakeYaml)
 
-    compileOnlyApi(libs.snakeYaml)
     compileOnlyApi(libs.netty)
     compileOnlyApi(libs.guava)
     compileOnlyApi(libs.checkerQual)

api/src/main/java/com/viaversion/viaversion/api/ViaManager.java

@@ -140,6 +140,13 @@ public interface ViaManager {
      */
     void addEnableListener(Runnable runnable);
 
+    /**
+     * Adds a runnable to be executed when ViaVersion has finished its init after the full server load.
+     *
+     * @param runnable runnable to be executed
+     */
+    void addPostEnableListener(Runnable runnable);
+
     /**
      * Returns whether the manager has been initialized (and protocols have been loaded).
      *

api/src/main/java/com/viaversion/viaversion/api/configuration/ViaVersionConfig.java

@@ -67,9 +67,9 @@ public interface ViaVersionConfig extends Config {
     boolean isShowNewDeathMessages();
 
     /**
-     * Get if metadata errors will be suppressed
+     * Get if entity data errors will be suppressed
      *
-     * @return true if metadata errors suppression is enabled
+     * @return true if entity data errors suppression is enabled
      */
     boolean isSuppressMetadataErrors();
 
@@ -292,13 +292,6 @@ public interface ViaVersionConfig extends Config {
      */
     boolean isDisable1_13AutoComplete();
 
-    /**
-     * Tries to minimize cooldown animation.
-     *
-     * @return true if enabled
-     */
-    boolean isMinimizeCooldown();
-
     /**
      * Enable the serverside blockconnections for 1.13+ clients
      *
@@ -464,4 +457,25 @@ public interface ViaVersionConfig extends Config {
      * @return true if enabled
      */
     boolean handleInvalidItemCount();
+
+    /**
+     * Tries to cancel block break/place sounds sent by 1.8 servers to 1.9+ clients to prevent them from playing twice
+     *
+     * @return true if enabled
+     */
+    boolean cancelBlockSounds();
+
+    /**
+     * Hides scoreboard numbers for 1.20.3+ clients on older server versions.
+     *
+     * @return true if enabled
+     */
+    boolean hideScoreboardNumbers();
+
+    /**
+     * Fixes 1.21+ clients on 1.20.5 servers placing water/lava buckets at the wrong location when moving fast.
+     *
+     * @return true if enabled
+     */
+    boolean fix1_21PlacementRotation();
 }

api/src/main/java/com/viaversion/viaversion/api/connection/StoredObject.java

@@ -29,6 +29,11 @@ public abstract class StoredObject implements StorableObject {
         this.user = user;
     }
 
+    public UserConnection user() {
+        return this.user;
+    }
+
+    @Deprecated
     public UserConnection getUser() {
         return user;
     }

api/src/main/java/com/viaversion/viaversion/api/connection/UserConnection.java

@@ -24,6 +24,7 @@ package com.viaversion.viaversion.api.connection;
 
 import com.viaversion.viaversion.api.configuration.ViaVersionConfig;
 import com.viaversion.viaversion.api.data.entity.EntityTracker;
+import com.viaversion.viaversion.api.minecraft.ClientWorld;
 import com.viaversion.viaversion.api.protocol.Protocol;
 import com.viaversion.viaversion.api.protocol.packet.PacketTracker;
 import com.viaversion.viaversion.api.protocol.packet.PacketWrapper;
@@ -99,14 +100,33 @@ public interface UserConnection {
     void addEntityTracker(Class<? extends Protocol> protocolClass, EntityTracker tracker);
 
     /**
-     * Clear stored objects and entity trackers.
+     * Returns the client world by the given protocol class if present.
+     *
+     * @param protocolClass protocol class
+     * @param <T>           client world type
+     * @return client world if present
+     */
+    @Nullable
+    <T extends ClientWorld> T getClientWorld(Class<? extends Protocol> protocolClass);
+
+    /**
+     * Adds a client world to the user connection.
+     * Does not override existing client worlds.
+     *
+     * @param protocolClass protocol class
+     * @param clientWorld   client world
+     */
+    void addClientWorld(Class<? extends Protocol> protocolClass, ClientWorld clientWorld);
+
+    /**
+     * Clear stored objects, entity trackers and client worlds.
      */
     default void clearStoredObjects() {
         clearStoredObjects(false);
     }
 
     /**
-     * Clear stored objects and entity trackers.
+     * Clear stored objects, entity trackers and client worlds.
      * If cleared for a proxy server switch, some stored objects and tracker data will be retained.
      *
      * @param isServerSwitch whether the clear is due to a server switch

api/src/main/java/com/viaversion/viaversion/api/data/MappingData.java

@@ -83,6 +83,10 @@ public interface MappingData {
 
     int getNewAttributeId(int id);
 
+    int getNewSoundId(int id);
+
+    int getOldSoundId(int i);
+
     /**
      * Returns a list of tags to send if present.
      *

api/src/main/java/com/viaversion/viaversion/api/data/MappingDataBase.java

@@ -46,6 +46,7 @@ public class MappingDataBase implements MappingData {
     protected ParticleMappings particleMappings;
     protected BiMappings itemMappings;
     protected BiMappings blockMappings;
+    protected BiMappings attributeMappings;
     protected Mappings blockStateMappings;
     protected Mappings blockEntityMappings;
     protected Mappings soundMappings;
@@ -53,7 +54,6 @@ public class MappingDataBase implements MappingData {
     protected Mappings enchantmentMappings;
     protected Mappings paintingMappings;
     protected Mappings menuMappings;
-    protected Mappings attributeMappings;
     protected Map<RegistryType, List<TagData>> tags;
 
     public MappingDataBase(final String unmappedVersion, final String mappedVersion) {
@@ -76,7 +76,7 @@ public class MappingDataBase implements MappingData {
         menuMappings = loadMappings(data, "menus");
         enchantmentMappings = loadMappings(data, "enchantments");
         paintingMappings = loadMappings(data, "paintings");
-        attributeMappings = loadMappings(data, "attributes");
+        attributeMappings = loadBiMappings(data, "attributes");
 
 
         final CompoundTag unmappedIdentifierData = readUnmappedIdentifiersFile("identifiers-" + unmappedVersion + ".nbt");
@@ -203,6 +203,16 @@ public class MappingDataBase implements MappingData {
         return checkValidity(id, attributeMappings.getNewId(id), "attributes");
     }
 
+    @Override
+    public int getNewSoundId(final int id) {
+        return checkValidity(id, soundMappings.getNewId(id), "sound");
+    }
+
+    @Override
+    public int getOldSoundId(final int i) {
+        return soundMappings.getNewIdOrDefault(i, 0);
+    }
+
     @Override
     public @Nullable List<TagData> getTags(final RegistryType type) {
         return tags != null ? tags.get(type) : null;
@@ -315,4 +325,4 @@ public class MappingDataBase implements MappingData {
 
     protected void loadExtras(final CompoundTag data) {
     }
-}
+}

api/src/main/java/com/viaversion/viaversion/api/data/MappingDataLoader.java

@@ -30,7 +30,6 @@ import com.google.gson.JsonObject;
 import com.google.gson.JsonSyntaxException;
 import com.viaversion.nbt.io.NBTIO;
 import com.viaversion.nbt.io.TagReader;
-import com.viaversion.nbt.tag.ByteTag;
 import com.viaversion.nbt.tag.CompoundTag;
 import com.viaversion.nbt.tag.IntArrayTag;
 import com.viaversion.nbt.tag.IntTag;
@@ -211,68 +210,64 @@ public class MappingDataLoader {
             return null;
         }
 
-        final ByteTag serializationStragetyTag = tag.getUnchecked("id");
-        final IntTag mappedSizeTag = tag.getUnchecked("mappedSize");
-        final byte strategy = serializationStragetyTag.asByte();
+        final int mappedSize = tag.getIntTag("mappedSize").asInt();
+        final byte strategy = tag.getByteTag("id").asByte();
         final V mappings;
         if (strategy == DIRECT_ID) {
             final IntArrayTag valuesTag = tag.getIntArrayTag("val");
-            return IntArrayMappings.of(valuesTag.getValue(), mappedSizeTag.asInt());
+            return IntArrayMappings.of(valuesTag.getValue(), mappedSize);
         } else if (strategy == SHIFTS_ID) {
-            final IntArrayTag shiftsAtTag = tag.getIntArrayTag("at");
-            final IntArrayTag shiftsTag = tag.getIntArrayTag("to");
-            final IntTag sizeTag = tag.getUnchecked("size");
-            final int[] shiftsAt = shiftsAtTag.getValue();
-            final int[] shiftsTo = shiftsTag.getValue();
-            final int size = sizeTag.asInt();
+            final int[] shiftsAt = tag.getIntArrayTag("at").getValue();
+            final int[] shiftsTo = tag.getIntArrayTag("to").getValue();
+            final int size = tag.getIntTag("size").asInt();
             mappings = holderSupplier.get(size);
 
-            // Handle values until first shift
             if (shiftsAt[0] != 0) {
+                // Add identity values before the first shift
                 final int to = shiftsAt[0];
                 for (int id = 0; id < to; id++) {
                     addConsumer.addTo(mappings, id, id);
                 }
             }
 
-            // Handle shifts
+            // Read shifts
             for (int i = 0; i < shiftsAt.length; i++) {
+                final boolean isLast = i == shiftsAt.length - 1;
                 final int from = shiftsAt[i];
-                final int to = i == shiftsAt.length - 1 ? size : shiftsAt[i + 1];
+                final int to = isLast ? size : shiftsAt[i + 1];
                 int mappedId = shiftsTo[i];
                 for (int id = from; id < to; id++) {
                     addConsumer.addTo(mappings, id, mappedId++);
                 }
             }
         } else if (strategy == CHANGES_ID) {
-            final IntArrayTag changesAtTag = tag.getIntArrayTag("at");
-            final IntArrayTag valuesTag = tag.getIntArrayTag("val");
-            final IntTag sizeTag = tag.getUnchecked("size");
+            final int[] changesAt = tag.getIntArrayTag("at").getValue();
+            final int[] values = tag.getIntArrayTag("val").getValue();
+            final int size = tag.getIntTag("size").asInt();
             final boolean fillBetween = tag.get("nofill") == null;
-            final int[] changesAt = changesAtTag.getValue();
-            final int[] values = valuesTag.getValue();
-            mappings = holderSupplier.get(sizeTag.asInt());
+            mappings = holderSupplier.get(size);
 
+            int nextUnhandledId = 0;
             for (int i = 0; i < changesAt.length; i++) {
-                final int id = changesAt[i];
+                final int changedId = changesAt[i];
                 if (fillBetween) {
                     // Fill from after the last change to before this change with unchanged ids
-                    final int previousId = i != 0 ? changesAt[i - 1] + 1 : 0;
-                    for (int identity = previousId; identity < id; identity++) {
-                        addConsumer.addTo(mappings, identity, identity);
+                    for (int id = nextUnhandledId; id < changedId; id++) {
+                        addConsumer.addTo(mappings, id, id);
                     }
+                    nextUnhandledId = changedId + 1;
                 }
 
                 // Assign the changed value
-                addConsumer.addTo(mappings, id, values[i]);
+                addConsumer.addTo(mappings, changedId, values[i]);
             }
         } else if (strategy == IDENTITY_ID) {
-            final IntTag sizeTag = tag.getUnchecked("size");
-            return new IdentityMappings(sizeTag.asInt(), mappedSizeTag.asInt());
+            final IntTag sizeTag = tag.getIntTag("size");
+            return new IdentityMappings(sizeTag.asInt(), mappedSize);
         } else {
             throw new IllegalArgumentException("Unknown serialization strategy: " + strategy);
         }
-        return mappingsSupplier.create(mappings, mappedSizeTag.asInt());
+        return mappingsSupplier.create(mappings, mappedSize);
     }
 
     public @Nullable List<String> identifiersFromGlobalIds(final CompoundTag mappingsTag, final String key) {
@@ -295,7 +290,7 @@ public class MappingDataLoader {
      * @return map with indexes hashed by their id value
      */
     public Object2IntMap<String> indexedObjectToMap(final JsonObject object) {
-        final Object2IntMap<String> map = new Object2IntOpenHashMap<>(object.size(), .99F);
+        final Object2IntMap<String> map = new Object2IntOpenHashMap<>(object.size());
         map.defaultReturnValue(-1);
         for (final Map.Entry<String, JsonElement> entry : object.entrySet()) {
             map.put(entry.getValue().getAsString(), Integer.parseInt(entry.getKey()));
@@ -310,7 +305,7 @@ public class MappingDataLoader {
      * @return map with indexes hashed by their id value
      */
     public Object2IntMap<String> arrayToMap(final JsonArray array) {
-        final Object2IntMap<String> map = new Object2IntOpenHashMap<>(array.size(), .99F);
+        final Object2IntMap<String> map = new Object2IntOpenHashMap<>(array.size());
         map.defaultReturnValue(-1);
         for (int i = 0; i < array.size(); i++) {
             map.put(array.get(i).getAsString(), i);

api/src/main/java/com/viaversion/viaversion/api/data/entity/EntityTracker.java

@@ -78,7 +78,7 @@ public interface EntityTracker {
     void removeEntity(int id);
 
     /**
-     * Clears stored entity types and data.
+     * Clears stored entity types and data, only leaving behind the client entity.
      */
     void clearEntities();
 
@@ -102,11 +102,19 @@ public interface EntityTracker {
     @Nullable StoredEntityData entityDataIfPresent(int id);
 
     /**
-     * Returns the client entity id or -1 if unset.
+     * Returns whether the client entity id has been set.
      *
-     * @return client entity id or -1 if unset
+     * @return whether the client entity id has been set
      */
-    int clientEntityId();
+    boolean hasClientEntityId();
+
+    /**
+     * Returns the client entity id. Should be wrapped around {@link #hasClientEntityId()}.
+     *
+     * @return client entity id
+     * @throws IllegalStateException if the client entity id has not been set
+     */
+    int clientEntityId() throws IllegalStateException;
 
     /**
      * Sets the client entity id.
@@ -169,12 +177,4 @@ public interface EntityTracker {
     @Nullable DimensionData dimensionData(int dimensionId);
 
     void setDimensions(Map<String, DimensionData> dimensions);
-
-    /**
-     * Adds the client player entity to the tracker.
-     * If the client entity has not been set yet, this will return false.
-     *
-     * @return whether the client has been tracked
-     */
-    boolean trackClientEntity();
 }

api/src/main/java/com/viaversion/viaversion/api/minecraft/ClientWorld.java

@@ -23,13 +23,12 @@
 package com.viaversion.viaversion.api.minecraft;
 
 import com.viaversion.viaversion.api.connection.StorableObject;
-import org.checkerframework.checker.nullness.qual.Nullable;
 
 /**
  * Stored up until 1.14 to be used in chunk sending.
  */
 public class ClientWorld implements StorableObject {
-    private Environment environment;
+    private Environment environment = Environment.NORMAL;
 
     public ClientWorld() {
     }
@@ -38,11 +37,20 @@ public class ClientWorld implements StorableObject {
         this.environment = environment;
     }
 
-    public @Nullable Environment getEnvironment() {
+    public Environment getEnvironment() {
         return environment;
     }
 
-    public void setEnvironment(final int environmentId) {
+    /**
+     * Sets the environment of the world and returns whether the environment was changed.
+     *
+     * @param environmentId the id of the environment to set
+     * @return whether the environment was changed
+     */
+    public boolean setEnvironment(final int environmentId) {
+        final int previousEnvironmentId = environment.id();
         this.environment = Environment.getEnvironmentById(environmentId);
+
+        return previousEnvironmentId != environmentId;
     }
 }

api/src/main/java/com/viaversion/viaversion/api/minecraft/Holder.java

@@ -22,6 +22,8 @@
  */
 package com.viaversion.viaversion.api.minecraft;
 
+import it.unimi.dsi.fastutil.ints.Int2IntFunction;
+
 public interface Holder<T> {
 
     /**
@@ -79,4 +81,12 @@ public interface Holder<T> {
      * @see #hasId()
      */
     int id();
+
+    /**
+     * Returns a new holder with the id rewritten using the given function, or self if this is a direct holder or the id did not change.
+     *
+     * @param rewriteFunction the function to rewrite the id
+     * @return a new holder with the id rewritten, or self
+     */
+    Holder<T> updateId(final Int2IntFunction rewriteFunction);
 }

api/src/main/java/com/viaversion/viaversion/api/minecraft/HolderImpl.java

@@ -23,6 +23,7 @@
 package com.viaversion.viaversion.api.minecraft;
 
 import com.google.common.base.Preconditions;
+import it.unimi.dsi.fastutil.ints.Int2IntFunction;
 
 final class HolderImpl<T> implements Holder<T> {
 
@@ -61,6 +62,22 @@ final class HolderImpl<T> implements Holder<T> {
         return id;
     }
 
+    @Override
+    public Holder<T> updateId(final Int2IntFunction rewriteFunction) {
+        if (isDirect()) {
+            return this;
+        }
+
+        final int rewrittenId = rewriteFunction.applyAsInt(id);
+        if (rewrittenId == id) {
+            return this;
+        }
+        if (rewrittenId == -1) {
+            throw new IllegalArgumentException("Received invalid id in updateId");
+        }
+        return Holder.of(rewrittenId);
+    }
+
     @Override
     public String toString() {
         return "HolderImpl{" +

api/src/main/java/com/viaversion/viaversion/api/minecraft/HolderSetImpl.java

@@ -64,7 +64,7 @@ final class HolderSetImpl extends EitherImpl<String, int[]> implements HolderSet
         final int[] ids = ids();
         final int[] mappedIds = new int[ids.length];
         for (int i = 0; i < mappedIds.length; i++) {
-            mappedIds[i] = idRewriter.apply(ids[i]);
+            mappedIds[i] = idRewriter.applyAsInt(ids[i]);
         }
         return new HolderSetImpl(mappedIds);
     }

api/src/main/java/com/viaversion/viaversion/api/minecraft/Particle.java

@@ -22,6 +22,7 @@
  */
 package com.viaversion.viaversion.api.minecraft;
 
+import com.viaversion.viaversion.api.minecraft.item.Item;
 import com.viaversion.viaversion.api.protocol.packet.PacketWrapper;
 import com.viaversion.viaversion.api.type.Type;
 import com.viaversion.viaversion.util.IdHolder;
@@ -72,6 +73,14 @@ public final class Particle implements IdHolder {
         arguments.set(index, new ParticleData<>(type, value));
     }
 
+    public Particle copy() {
+        final Particle particle = new Particle(id);
+        for (ParticleData<?> argument : arguments) {
+            particle.arguments.add(argument.copy());
+        }
+        return particle;
+    }
+
     @Override
     public String toString() {
         return "Particle{" +
@@ -109,6 +118,14 @@ public final class Particle implements IdHolder {
             wrapper.write(type, value);
         }
 
+        public ParticleData<T> copy() {
+            if (value instanceof Item item) {
+                return new ParticleData<>(type, (T) item.copy());
+            } else {
+                return new ParticleData<>(type, value);
+            }
+        }
+
         @Override
         public String toString() {
             return "ParticleData{" +

api/src/main/java/com/viaversion/viaversion/api/minecraft/data/StructuredData.java

@@ -52,16 +52,14 @@ public interface StructuredData<T> extends IdHolder {
         return new EmptyStructuredData<>(key, id);
     }
 
-    void setValue(final T value);
+    @Nullable T value();
 
-    void write(final ByteBuf buffer);
+    void setValue(final T value);
 
     void setId(final int id);
 
     StructuredDataKey<T> key();
 
-    @Nullable T value();
-
     /**
      * Returns whether the structured data is present. Even if true, the value may be null.
      *
@@ -77,4 +75,6 @@ public interface StructuredData<T> extends IdHolder {
      * @return true if the structured data is empty
      */
     boolean isEmpty();
+
+    void write(final ByteBuf buffer);
 }

api/src/main/java/com/viaversion/viaversion/api/minecraft/data/StructuredDataContainer.java

@@ -33,6 +33,26 @@ import java.util.Map;
 import java.util.function.Function;
 import org.checkerframework.checker.nullness.qual.Nullable;
 
+/**
+ * Loosely represents Minecraft's data component patch, but may also be used for an item's full data components.
+ * <p>
+ * The most commonly used methods will ignore empty data (aka empty overrides that remove item defaults) since those will rarely be needed.
+ * These are:
+ * <ul>
+ *     <li>{@link #get(StructuredDataKey)}</li>
+ *     <li>{@link #set(StructuredDataKey, Object)}</li>
+ *     <li>{@link #set(StructuredDataKey)}</li>
+ *     <li>{@link #getNonEmptyData(StructuredDataKey)}</li>
+ *     <li>{@link #hasValue(StructuredDataKey)}</li>
+ * </ul>
+ *
+ * To interact with empty patches specifically, use:
+ * <ul>
+ *     <li>{@link #setEmpty(StructuredDataKey)}</li>
+ *     <li>{@link #hasEmpty(StructuredDataKey)}</li>
+ * </ul>
+ * Other methods (e.g. {@link #getData(StructuredDataKey)} and {@link #has(StructuredDataKey)}) will handle both empty and non-empty data.
+ */
 public final class StructuredDataContainer {
 
     private final Map<StructuredDataKey<?>, StructuredData<?>> data;
@@ -55,66 +75,45 @@ public final class StructuredDataContainer {
     }
 
     /**
-     * Returns structured data by id if present.
+     * Returns the non-empty value by id if present.
+     *
+     * @param key serializer id
+     * @param <T> data type
+     * @return structured data
+     * @see #hasEmpty(StructuredDataKey)
+     */
+    public @Nullable <T> T get(final StructuredDataKey<T> key) {
+        final StructuredData<?> data = this.data.get(key);
+        if (data == null || data.isEmpty()) {
+            return null;
+        }
+        //noinspection unchecked
+        return ((StructuredData<T>) data).value();
+    }
+
+    /**
+     * Returns structured data by id if present, either empty or non-empty.
      *
      * @param key serializer id
      * @param <T> data type
      * @return structured data
      */
-    public @Nullable <T> StructuredData<T> get(final StructuredDataKey<T> key) {
+    public @Nullable <T> StructuredData<T> getData(final StructuredDataKey<T> key) {
         //noinspection unchecked
         return (StructuredData<T>) this.data.get(key);
     }
 
     /**
-     * Returns structured data by id if not empty.
+     * Returns non-empty structured data by id if present.
      *
      * @param key serializer id
      * @param <T> data type
-     * @return structured data if not empty
+     * @return non-empty structured data
      */
-    public @Nullable <T> StructuredData<T> getNonEmpty(final StructuredDataKey<T> key) {
+    public @Nullable <T> StructuredData<T> getNonEmptyData(final StructuredDataKey<T> key) {
+        final StructuredData<?> data = this.data.get(key);
         //noinspection unchecked
-        final StructuredData<T> data = (StructuredData<T>) this.data.get(key);
-        return data != null && data.isPresent() ? data : null;
-    }
-
-    /**
-     * Returns structured data by id if not empty, or creates it.
-     *
-     * @param key             serializer id
-     * @param mappingFunction function to create structured data if not present
-     * @param <T>             data type
-     * @return structured data if not empty
-     */
-    public <T> StructuredData<T> computeIfAbsent(final StructuredDataKey<T> key, final Function<StructuredDataKey<T>, T> mappingFunction) {
-        final StructuredData<T> data = this.getNonEmpty(key);
-        if (data != null) {
-            return data;
-        }
-
-        final int id = serializerId(key);
-        final StructuredData<T> empty = StructuredData.of(key, mappingFunction.apply(key), id);
-        this.data.put(key, empty);
-        return empty;
-    }
-
-    /**
-     * Updates and returns the structured data by id if not empty.
-     *
-     * @param key             serializer id
-     * @param mappingFunction function to update existing data
-     * @param <T>             data type
-     * @return updated structured data if not empty
-     */
-    public <T> @Nullable StructuredData<T> updateIfPresent(final StructuredDataKey<T> key, final Function<T, T> mappingFunction) {
-        final StructuredData<T> data = this.getNonEmpty(key);
-        if (data == null) {
-            return null;
-        }
-
-        data.setValue(mappingFunction.apply(data.value()));
-        return data;
+        return data != null && data.isPresent() ? (StructuredData<T>) data : null;
     }
 
     public <T> void set(final StructuredDataKey<T> key, final T value) {
@@ -124,49 +123,105 @@ public final class StructuredDataContainer {
         }
     }
 
-    public <T> void replaceKey(final StructuredDataKey<T> key, final StructuredDataKey<T> toKey) {
-        replace(key, toKey, Function.identity());
-    }
-
-    public <T, V> void replace(final StructuredDataKey<T> key, final StructuredDataKey<V> toKey, final Function<T, V> valueMapper) {
-        final StructuredData<T> data = remove(key);
-        if (data == null) {
-            return;
-        }
-
-        if (data.isPresent()) {
-            set(toKey, valueMapper.apply(data.value()));
-        } else {
-            addEmpty(toKey);
-        }
-    }
-
     public void set(final StructuredDataKey<Unit> key) {
         this.set(key, Unit.INSTANCE);
     }
 
-    public void addEmpty(final StructuredDataKey<?> key) {
+    public void setEmpty(final StructuredDataKey<?> key) {
         // Empty optional to override the Minecraft default
         this.data.put(key, StructuredData.empty(key, serializerId(key)));
     }
 
     /**
-     * Removes and returns structured data by the given key.
+     * Updates the structured data by id if not empty.
      *
-     * @param key serializer key
-     * @param <T> data type
-     * @return removed structured data
+     * @param key         serializer id
+     * @param valueMapper function to update existing data
+     * @param <T>         data type
      */
-    public @Nullable <T> StructuredData<T> remove(final StructuredDataKey<T> key) {
-        final StructuredData<?> data = this.data.remove(key);
-        //noinspection unchecked
-        return data != null ? (StructuredData<T>) data : null;
+    public <T> void replace(final StructuredDataKey<T> key, final Function<T, @Nullable T> valueMapper) {
+        final StructuredData<T> data = this.getNonEmptyData(key);
+        if (data == null) {
+            return;
+        }
+
+        final T replacement = valueMapper.apply(data.value());
+        if (replacement != null) {
+            data.setValue(replacement);
+        } else {
+            this.data.remove(key);
+        }
     }
 
-    public boolean contains(final StructuredDataKey<?> key) {
+    public <T> void replaceKey(final StructuredDataKey<T> key, final StructuredDataKey<T> toKey) {
+        replace(key, toKey, Function.identity());
+    }
+
+    public <T, V> void replace(final StructuredDataKey<T> key, final StructuredDataKey<V> toKey, final Function<T, @Nullable V> valueMapper) {
+        final StructuredData<?> data = this.data.remove(key);
+        if (data == null) {
+            return;
+        }
+
+        if (data.isPresent()) {
+            //noinspection unchecked
+            final T value = (T) data.value();
+            final V replacement = valueMapper.apply(value);
+            if (replacement != null) {
+                set(toKey, replacement);
+            }
+        } else {
+            // Also replace the key for empty data
+            setEmpty(toKey);
+        }
+    }
+
+    /**
+     * Removes data by the given key.
+     *
+     * @param key data key
+     * @see #replace(StructuredDataKey, Function)
+     * @see #replace(StructuredDataKey, StructuredDataKey, Function)
+     * @see #replaceKey(StructuredDataKey, StructuredDataKey)
+     */
+    public void remove(final StructuredDataKey<?> key) {
+        this.data.remove(key);
+    }
+
+    /**
+     * Returns whether there is data for the given key, either empty or non-empty.
+     *
+     * @param key data key
+     * @return whether there data for the given key
+     * @see #hasEmpty(StructuredDataKey)
+     * @see #hasValue(StructuredDataKey)
+     */
+    public boolean has(final StructuredDataKey<?> key) {
         return this.data.containsKey(key);
     }
 
+    /**
+     * Returns whether there is non-empty data for the given key.
+     *
+     * @param key data key
+     * @return whether there is non-empty data for the given key
+     */
+    public boolean hasValue(final StructuredDataKey<?> key) {
+        final StructuredData<?> data = this.data.get(key);
+        return data != null && data.isPresent();
+    }
+
+    /**
+     * Returns whether the structured data has an empty patch/override.
+     *
+     * @param key serializer id
+     * @return whether the structured data has an empty patch/override
+     */
+    public boolean hasEmpty(final StructuredDataKey<?> key) {
+        final StructuredData<?> data = this.data.get(key);
+        return data != null && data.isEmpty();
+    }
+
     /**
      * Sets the lookup for serializer ids. Required to call most of the other methods.
      *
@@ -212,6 +267,8 @@ public final class StructuredDataContainer {
     public String toString() {
         return "StructuredDataContainer{" +
             "data=" + data +
+            ", lookup=" + lookup +
+            ", mappedNames=" + mappedNames +
             '}';
     }
 }

api/src/main/java/com/viaversion/viaversion/api/minecraft/entities/EntityTypes1_12.java

@@ -101,7 +101,7 @@ public class EntityTypes1_12 {
 
         LIVING_ENTITY_BASE(ENTITY),
         ARMOR_STAND(30, LIVING_ENTITY_BASE),
-        PLAYER(ENTITY), // Needed for entity (un)tracking
+        PLAYER(LIVING_ENTITY_BASE), // Needed for entity (un)tracking
 
         // Living entities as a larger subclass
         LIVING_ENTITY(LIVING_ENTITY_BASE),

api/src/main/java/com/viaversion/viaversion/api/minecraft/entities/EntityTypes1_14.java

@@ -51,11 +51,12 @@ public enum EntityTypes1_14 implements EntityType {
 
     // Projectiles
     PROJECTILE(ENTITY, null), // Not actually its own abstract type, but useful for categorizing
-    SNOWBALL(PROJECTILE),
-    ENDER_PEARL(PROJECTILE),
-    EGG(PROJECTILE),
+    ITEM_PROJECTILE(PROJECTILE, null),
+    SNOWBALL(ITEM_PROJECTILE),
+    ENDER_PEARL(ITEM_PROJECTILE),
+    EGG(ITEM_PROJECTILE),
     POTION(PROJECTILE),
-    EXPERIENCE_BOTTLE(PROJECTILE),
+    EXPERIENCE_BOTTLE(ITEM_PROJECTILE),
     FIREWORK_ROCKET(PROJECTILE),
     LLAMA_SPIT(PROJECTILE),
     SHULKER_BULLET(PROJECTILE),

api/src/main/java/com/viaversion/viaversion/api/minecraft/entities/EntityTypes1_15.java

@@ -51,11 +51,12 @@ public enum EntityTypes1_15 implements EntityType {
 
     // Projectiles
     PROJECTILE(ENTITY, null), // Not actually its own abstract type, but useful for categorizing
-    SNOWBALL(PROJECTILE),
-    ENDER_PEARL(PROJECTILE),
-    EGG(PROJECTILE),
+    ITEM_PROJECTILE(PROJECTILE, null),
+    SNOWBALL(ITEM_PROJECTILE),
+    ENDER_PEARL(ITEM_PROJECTILE),
+    EGG(ITEM_PROJECTILE),
     POTION(PROJECTILE),
-    EXPERIENCE_BOTTLE(PROJECTILE),
+    EXPERIENCE_BOTTLE(ITEM_PROJECTILE),
     FIREWORK_ROCKET(PROJECTILE),
     LLAMA_SPIT(PROJECTILE),
     SHULKER_BULLET(PROJECTILE),

api/src/main/java/com/viaversion/viaversion/api/minecraft/entities/EntityTypes1_16.java

@@ -51,11 +51,12 @@ public enum EntityTypes1_16 implements EntityType {
 
     // Projectiles
     PROJECTILE(ENTITY, null), // Not actually its own abstract type, but useful for categorizing
-    SNOWBALL(PROJECTILE),
-    ENDER_PEARL(PROJECTILE),
-    EGG(PROJECTILE),
-    POTION(PROJECTILE),
-    EXPERIENCE_BOTTLE(PROJECTILE),
+    ITEM_PROJECTILE(PROJECTILE, null),
+    SNOWBALL(ITEM_PROJECTILE),
+    ENDER_PEARL(ITEM_PROJECTILE),
+    EGG(ITEM_PROJECTILE),
+    POTION(ITEM_PROJECTILE),
+    EXPERIENCE_BOTTLE(ITEM_PROJECTILE),
     FIREWORK_ROCKET(PROJECTILE),
     LLAMA_SPIT(PROJECTILE),
     SHULKER_BULLET(PROJECTILE),

api/src/main/java/com/viaversion/viaversion/api/minecraft/entities/EntityTypes1_16_2.java

@@ -51,11 +51,12 @@ public enum EntityTypes1_16_2 implements EntityType {
 
     // Projectiles
     PROJECTILE(ENTITY, null), // Not actually its own abstract type, but useful for categorizing
-    SNOWBALL(PROJECTILE),
-    ENDER_PEARL(PROJECTILE),
-    EGG(PROJECTILE),
-    POTION(PROJECTILE),
-    EXPERIENCE_BOTTLE(PROJECTILE),
+    ITEM_PROJECTILE(PROJECTILE, null),
+    SNOWBALL(ITEM_PROJECTILE),
+    ENDER_PEARL(ITEM_PROJECTILE),
+    EGG(ITEM_PROJECTILE),
+    POTION(ITEM_PROJECTILE),
+    EXPERIENCE_BOTTLE(ITEM_PROJECTILE),
     FIREWORK_ROCKET(PROJECTILE),
     LLAMA_SPIT(PROJECTILE),
     SHULKER_BULLET(PROJECTILE),

api/src/main/java/com/viaversion/viaversion/api/minecraft/entities/EntityTypes1_17.java

@@ -53,11 +53,12 @@ public enum EntityTypes1_17 implements EntityType {
 
     // Projectiles
     PROJECTILE(ENTITY, null), // Not actually its own abstract type, but useful for categorizing
-    SNOWBALL(PROJECTILE),
-    ENDER_PEARL(PROJECTILE),
-    EGG(PROJECTILE),
-    POTION(PROJECTILE),
-    EXPERIENCE_BOTTLE(PROJECTILE),
+    ITEM_PROJECTILE(PROJECTILE, null),
+    SNOWBALL(ITEM_PROJECTILE),
+    ENDER_PEARL(ITEM_PROJECTILE),
+    EGG(ITEM_PROJECTILE),
+    POTION(ITEM_PROJECTILE),
+    EXPERIENCE_BOTTLE(ITEM_PROJECTILE),
     FIREWORK_ROCKET(PROJECTILE),
     LLAMA_SPIT(PROJECTILE),
     SHULKER_BULLET(PROJECTILE),

api/src/main/java/com/viaversion/viaversion/api/minecraft/entities/EntityTypes1_19.java

@@ -53,11 +53,12 @@ public enum EntityTypes1_19 implements EntityType {
 
     // Projectiles
     PROJECTILE(ENTITY, null), // Not actually its own abstract type, but useful for categorizing
-    SNOWBALL(PROJECTILE),
-    ENDER_PEARL(PROJECTILE),
-    EGG(PROJECTILE),
-    POTION(PROJECTILE),
-    EXPERIENCE_BOTTLE(PROJECTILE),
+    ITEM_PROJECTILE(PROJECTILE, null),
+    SNOWBALL(ITEM_PROJECTILE),
+    ENDER_PEARL(ITEM_PROJECTILE),
+    EGG(ITEM_PROJECTILE),
+    POTION(ITEM_PROJECTILE),
+    EXPERIENCE_BOTTLE(ITEM_PROJECTILE),
     FIREWORK_ROCKET(PROJECTILE),
     LLAMA_SPIT(PROJECTILE),
     SHULKER_BULLET(PROJECTILE),

api/src/main/java/com/viaversion/viaversion/api/minecraft/entities/EntityTypes1_19_3.java

@@ -53,11 +53,12 @@ public enum EntityTypes1_19_3 implements EntityType {
 
     // Projectiles
     PROJECTILE(ENTITY, null), // Not actually its own abstract type, but useful for categorizing
-    SNOWBALL(PROJECTILE),
-    ENDER_PEARL(PROJECTILE),
-    EGG(PROJECTILE),
-    POTION(PROJECTILE),
-    EXPERIENCE_BOTTLE(PROJECTILE),
+    ITEM_PROJECTILE(PROJECTILE, null),
+    SNOWBALL(ITEM_PROJECTILE),
+    ENDER_PEARL(ITEM_PROJECTILE),
+    EGG(ITEM_PROJECTILE),
+    POTION(ITEM_PROJECTILE),
+    EXPERIENCE_BOTTLE(ITEM_PROJECTILE),
     FIREWORK_ROCKET(PROJECTILE),
     LLAMA_SPIT(PROJECTILE),
     SHULKER_BULLET(PROJECTILE),

api/src/main/java/com/viaversion/viaversion/api/minecraft/entities/EntityTypes1_19_4.java

@@ -59,11 +59,12 @@ public enum EntityTypes1_19_4 implements EntityType {
 
     // Projectiles
     PROJECTILE(ENTITY, null), // Not actually its own abstract type, but useful for categorizing
-    SNOWBALL(PROJECTILE),
-    ENDER_PEARL(PROJECTILE),
-    EGG(PROJECTILE),
-    POTION(PROJECTILE),
-    EXPERIENCE_BOTTLE(PROJECTILE),
+    ITEM_PROJECTILE(PROJECTILE, null),
+    SNOWBALL(ITEM_PROJECTILE),
+    ENDER_PEARL(ITEM_PROJECTILE),
+    EGG(ITEM_PROJECTILE),
+    POTION(ITEM_PROJECTILE),
+    EXPERIENCE_BOTTLE(ITEM_PROJECTILE),
     FIREWORK_ROCKET(PROJECTILE),
     LLAMA_SPIT(PROJECTILE),
     SHULKER_BULLET(PROJECTILE),

api/src/main/java/com/viaversion/viaversion/api/minecraft/entities/EntityTypes1_20_3.java

@@ -59,11 +59,12 @@ public enum EntityTypes1_20_3 implements EntityType {
 
     // Projectiles
     PROJECTILE(ENTITY, null), // Not actually its own abstract type, but useful for categorizing
-    SNOWBALL(PROJECTILE),
-    ENDER_PEARL(PROJECTILE),
-    EGG(PROJECTILE),
-    POTION(PROJECTILE),
-    EXPERIENCE_BOTTLE(PROJECTILE),
+    ITEM_PROJECTILE(PROJECTILE, null),
+    SNOWBALL(ITEM_PROJECTILE),
+    ENDER_PEARL(ITEM_PROJECTILE),
+    EGG(ITEM_PROJECTILE),
+    POTION(ITEM_PROJECTILE),
+    EXPERIENCE_BOTTLE(ITEM_PROJECTILE),
     FIREWORK_ROCKET(PROJECTILE),
     LLAMA_SPIT(PROJECTILE),
     SHULKER_BULLET(PROJECTILE),

api/src/main/java/com/viaversion/viaversion/api/minecraft/entities/EntityTypes1_20_5.java

@@ -59,12 +59,13 @@ public enum EntityTypes1_20_5 implements EntityType {
     GLOW_ITEM_FRAME(ITEM_FRAME),
 
     // Projectiles
-    PROJECTILE(ENTITY, null), // Not actually its own abstract type, but useful for categorizing
-    SNOWBALL(PROJECTILE),
-    ENDER_PEARL(PROJECTILE),
-    EGG(PROJECTILE),
-    POTION(PROJECTILE),
-    EXPERIENCE_BOTTLE(PROJECTILE),
+    PROJECTILE(ENTITY, null),
+    ITEM_PROJECTILE(PROJECTILE, null),
+    SNOWBALL(ITEM_PROJECTILE),
+    ENDER_PEARL(ITEM_PROJECTILE),
+    EGG(ITEM_PROJECTILE),
+    POTION(ITEM_PROJECTILE),
+    EXPERIENCE_BOTTLE(ITEM_PROJECTILE),
     FIREWORK_ROCKET(PROJECTILE),
     LLAMA_SPIT(PROJECTILE),
     SHULKER_BULLET(PROJECTILE),

api/src/main/java/com/viaversion/viaversion/api/minecraft/entities/EntityTypes1_8.java

@@ -93,7 +93,7 @@ public class EntityTypes1_8 {
 
         LIVING_ENTITY_BASE(ENTITY),
         ARMOR_STAND(30, LIVING_ENTITY_BASE),
-        PLAYER(LIVING_ENTITY_BASE), // Needed for entity (un)tracking and metadata indexing
+        PLAYER(LIVING_ENTITY_BASE), // Needed for entity (un)tracking and entity data indexing
 
         // Living entities as a larger subclass
         LIVING_ENTITY(48, LIVING_ENTITY_BASE),

api/src/main/java/com/viaversion/viaversion/api/minecraft/entities/EntityTypes1_9.java

@@ -99,7 +99,7 @@ public class EntityTypes1_9 {
 
         LIVING_ENTITY_BASE(ENTITY),
         ARMOR_STAND(30, LIVING_ENTITY_BASE),
-        PLAYER(ENTITY), // Needed for entity (un)tracking
+        PLAYER(LIVING_ENTITY_BASE), // Needed for entity (un)tracking
 
         // Living entities as a larger subclass
         LIVING_ENTITY(48, LIVING_ENTITY_BASE),

api/src/main/java/com/viaversion/viaversion/api/minecraft/entitydata/EntityData.java

@@ -28,21 +28,21 @@ import org.checkerframework.checker.nullness.qual.Nullable;
 
 public final class EntityData {
     private int id;
-    private EntityDataType metaType;
+    private EntityDataType dataType;
     private Object value;
 
     /**
-     * Creates a new metadata instance.
+     * Creates a new entity data instance.
      *
-     * @param id       metadata index
-     * @param metaType metadata type
+     * @param id       data index
+     * @param dataType data type
      * @param value    value if present
-     * @throws IllegalArgumentException if the value and metaType are incompatible
+     * @throws IllegalArgumentException if the value and dataType are incompatible
      */
-    public EntityData(int id, EntityDataType metaType, @Nullable Object value) {
+    public EntityData(int id, EntityDataType dataType, @Nullable Object value) {
         this.id = id;
-        this.metaType = metaType;
-        this.value = checkValue(metaType, value);
+        this.dataType = dataType;
+        this.value = checkValue(dataType, value);
     }
 
     public int id() {
@@ -54,19 +54,19 @@ public final class EntityData {
     }
 
     public EntityDataType dataType() {
-        return metaType;
+        return dataType;
     }
 
     /**
-     * Sets the metadata type if compatible with the current value.
+     * Sets the entity data type if compatible with the current value.
      *
-     * @param metaType metadata type
-     * @throws IllegalArgumentException if the metadata type and current value are incompatible
+     * @param dataType entity data type
+     * @throws IllegalArgumentException if the entity data type and current value are incompatible
      * @see #setTypeAndValue(EntityDataType, Object)
      */
-    public void setDataType(EntityDataType metaType) {
-        checkValue(metaType, this.value);
-        this.metaType = metaType;
+    public void setDataType(EntityDataType dataType) {
+        checkValue(dataType, this.value);
+        this.dataType = dataType;
     }
 
     public @Nullable <T> T value() {
@@ -78,32 +78,32 @@ public final class EntityData {
     }
 
     /**
-     * Sets the metadata value if compatible with the current meta type.
+     * Sets the entity data value if compatible with the current data type.
      *
      * @param value value
-     * @throws IllegalArgumentException if the value and current metaType are incompatible
+     * @throws IllegalArgumentException if the value and current dataType are incompatible
      * @see #setTypeAndValue(EntityDataType, Object)
      */
     public void setValue(@Nullable Object value) {
-        this.value = checkValue(this.metaType, value);
+        this.value = checkValue(this.dataType, value);
     }
 
     /**
-     * Sets metadata type and value.
+     * Sets entity data type and value.
      *
-     * @param metaType metadata type
+     * @param dataType entity data type
      * @param value    value
-     * @throws IllegalArgumentException if the value and metaType are incompatible
+     * @throws IllegalArgumentException if the value and dataType are incompatible
      */
-    public void setTypeAndValue(EntityDataType metaType, @Nullable Object value) {
-        this.value = checkValue(metaType, value);
-        this.metaType = metaType;
+    public void setTypeAndValue(EntityDataType dataType, @Nullable Object value) {
+        this.value = checkValue(dataType, value);
+        this.dataType = dataType;
     }
 
-    private Object checkValue(EntityDataType metaType, @Nullable Object value) {
-        Preconditions.checkNotNull(metaType);
-        if (value != null && !metaType.type().getOutputClass().isAssignableFrom(value.getClass())) {
-            throw new IllegalArgumentException("Metadata value and metaType are incompatible. Type=" + metaType
+    private Object checkValue(EntityDataType dataType, @Nullable Object value) {
+        Preconditions.checkNotNull(dataType);
+        if (value != null && !dataType.type().getOutputClass().isAssignableFrom(value.getClass())) {
+            throw new IllegalArgumentException("Entity data value and dataType are incompatible. Type=" + dataType
                 + ", value=" + value + " (" + value.getClass().getSimpleName() + ")");
         }
         return value;
@@ -111,32 +111,32 @@ public final class EntityData {
 
     @Deprecated
     public void setDataTypeUnsafe(EntityDataType type) {
-        this.metaType = type;
+        this.dataType = type;
     }
 
     @Override
     public boolean equals(final Object o) {
         if (this == o) return true;
         if (o == null || getClass() != o.getClass()) return false;
-        EntityData metadata = (EntityData) o;
-        if (id != metadata.id) return false;
-        if (metaType != metadata.metaType) return false;
-        return Objects.equals(value, metadata.value);
+        EntityData entityData = (EntityData) o;
+        if (id != entityData.id) return false;
+        if (dataType != entityData.dataType) return false;
+        return Objects.equals(value, entityData.value);
     }
 
     @Override
     public int hashCode() {
         int result = id;
-        result = 31 * result + metaType.hashCode();
+        result = 31 * result + dataType.hashCode();
         result = 31 * result + (value != null ? value.hashCode() : 0);
         return result;
     }
 
     @Override
     public String toString() {
-        return "Metadata{" +
+        return "EntityData{" +
             "id=" + id +
-            ", metaType=" + metaType +
+            ", dataType=" + dataType +
             ", value=" + value +
             '}';
     }

api/src/main/java/com/viaversion/viaversion/api/minecraft/entitydata/EntityDataType.java

@@ -35,7 +35,7 @@ public interface EntityDataType {
     Type type();
 
     /**
-     * Get type id from the specific MetaDataType
+     * Get type id from the specific EntityDataType
      *
      * @return Type id as an integer
      */
@@ -67,7 +67,7 @@ public interface EntityDataType {
 
         @Override
         public String toString() {
-            return "EntityDataType{" +
+            return "EntityDataTypeImpl{" +
                 "typeId=" + typeId +
                 ", type=" + type +
                 '}';
@@ -77,9 +77,9 @@ public interface EntityDataType {
         public boolean equals(final Object o) {
             if (this == o) return true;
             if (o == null || getClass() != o.getClass()) return false;
-            final EntityDataTypeImpl metaType = (EntityDataTypeImpl) o;
-            if (typeId != metaType.typeId) return false;
-            return type.equals(metaType.type);
+            final EntityDataTypeImpl dataType = (EntityDataTypeImpl) o;
+            if (typeId != dataType.typeId) return false;
+            return type.equals(dataType.type);
         }
 
         @Override

api/src/main/java/com/viaversion/viaversion/api/minecraft/entitydata/types/AbstractEntityDataTypes.java

@@ -44,8 +44,8 @@ public abstract class AbstractEntityDataTypes implements EntityDataTypes {
     }
 
     protected EntityDataType add(final int typeId, final Type<?> type) {
-        final EntityDataType metaType = EntityDataType.create(typeId, type);
-        values[typeId] = metaType;
-        return metaType;
+        final EntityDataType dataType = EntityDataType.create(typeId, type);
+        values[typeId] = dataType;
+        return dataType;
     }
 }

api/src/main/java/com/viaversion/viaversion/api/minecraft/entitydata/types/EntityDataTypes.java

@@ -27,18 +27,18 @@ import com.viaversion.viaversion.api.minecraft.entitydata.EntityDataType;
 public interface EntityDataTypes {
 
     /**
-     * Returns the meta type by the given id.
+     * Returns the data type by the given id.
      *
      * @param id type id
-     * @return meta type by id
+     * @return data type by id
      * @throws IndexOutOfBoundsException if id is out of bounds
      */
     EntityDataType byId(int id);
 
     /**
-     * Returns an array of meta types.
+     * Returns an array of data types.
      *
-     * @return array of meta types
+     * @return array of data types
      */
     EntityDataType[] values();
 }

api/src/main/java/com/viaversion/viaversion/api/minecraft/item/DataItem.java

@@ -124,11 +124,11 @@ public class DataItem implements Item {
 
     @Override
     public String toString() {
-        return "Item{" +
+        return "DataItem{" +
             "identifier=" + identifier +
             ", amount=" + amount +
             ", data=" + data +
             ", tag=" + tag +
             '}';
     }
-}
+}

api/src/main/java/com/viaversion/viaversion/api/minecraft/item/data/AttributeModifiers1_21.java

@@ -26,6 +26,7 @@ import com.viaversion.viaversion.api.type.Type;
 import com.viaversion.viaversion.api.type.Types;
 import com.viaversion.viaversion.api.type.types.ArrayType;
 import io.netty.buffer.ByteBuf;
+import it.unimi.dsi.fastutil.ints.Int2IntFunction;
 
 public record AttributeModifiers1_21(AttributeModifier[] modifiers, boolean showInTooltip) {
 
@@ -44,6 +45,15 @@ public record AttributeModifiers1_21(AttributeModifier[] modifiers, boolean show
         }
     };
 
+    public AttributeModifiers1_21 rewrite(final Int2IntFunction rewriteFunction) {
+        final AttributeModifier[] modifiers = new AttributeModifier[this.modifiers.length];
+        for (int i = 0; i < this.modifiers.length; i++) {
+            final AttributeModifier modifier = this.modifiers[i];
+            modifiers[i] = new AttributeModifier(rewriteFunction.applyAsInt(modifier.attribute()), modifier.modifier(), modifier.slotType());
+        }
+        return new AttributeModifiers1_21(modifiers, showInTooltip);
+    }
+
     public record AttributeModifier(int attribute, ModifierData modifier, int slotType) {
 
         public static final Type<AttributeModifier> TYPE = new Type<>(AttributeModifier.class) {

api/src/main/java/com/viaversion/viaversion/api/minecraft/item/data/Instrument.java

@@ -27,6 +27,7 @@ import com.viaversion.viaversion.api.minecraft.SoundEvent;
 import com.viaversion.viaversion.api.type.Types;
 import com.viaversion.viaversion.api.type.types.misc.HolderType;
 import io.netty.buffer.ByteBuf;
+import it.unimi.dsi.fastutil.ints.Int2IntFunction;
 
 public record Instrument(Holder<SoundEvent> soundEvent, int useDuration, float range) {
 
@@ -47,4 +48,8 @@ public record Instrument(Holder<SoundEvent> soundEvent, int useDuration, float r
         }
     };
 
+    public Instrument rewrite(final Int2IntFunction soundIdRewriteFunction) {
+        final Holder<SoundEvent> soundEvent = this.soundEvent.updateId(soundIdRewriteFunction);
+        return soundEvent == this.soundEvent ? this : new Instrument(soundEvent, useDuration, range);
+    }
 }

api/src/main/java/com/viaversion/viaversion/api/minecraft/item/data/JukeboxPlayable.java

@@ -30,6 +30,7 @@ import com.viaversion.viaversion.api.type.Types;
 import com.viaversion.viaversion.api.type.types.misc.HolderType;
 import com.viaversion.viaversion.util.Either;
 import io.netty.buffer.ByteBuf;
+import it.unimi.dsi.fastutil.ints.Int2IntFunction;
 
 public record JukeboxPlayable(Either<Holder<JukeboxSong>, String> song, boolean showInTooltip) {
 
@@ -56,6 +57,20 @@ public record JukeboxPlayable(Either<Holder<JukeboxSong>, String> song, boolean
         }
     };
 
+    public JukeboxPlayable rewrite(final Int2IntFunction soundIdRewriteFunction) {
+        if (song.isRight()) {
+            return this;
+        }
+
+        final Holder<JukeboxSong> songHolder = this.song.left();
+        if (songHolder.hasId()) {
+            return this;
+        }
+
+        final JukeboxSong rewrittenSong = songHolder.value().rewrite(soundIdRewriteFunction);
+        return rewrittenSong == songHolder.value() ? this : new JukeboxPlayable(Holder.of(rewrittenSong), showInTooltip);
+    }
+
     public record JukeboxSong(Holder<SoundEvent> soundEvent, Tag description,
                               float lengthInSeconds, int comparatorOutput) {
 
@@ -77,5 +92,10 @@ public record JukeboxPlayable(Either<Holder<JukeboxSong>, String> song, boolean
                 Types.VAR_INT.writePrimitive(buffer, value.comparatorOutput);
             }
         };
+
+        public JukeboxSong rewrite(final Int2IntFunction soundIdRewriteFunction) {
+            final Holder<SoundEvent> soundEvent = this.soundEvent.updateId(soundIdRewriteFunction);
+            return soundEvent == this.soundEvent ? this : new JukeboxSong(soundEvent, description, lengthInSeconds, comparatorOutput);
+        }
     }
 }

api/src/main/java/com/viaversion/viaversion/api/minecraft/item/data/MapDecorations.java

@@ -1,56 +0,0 @@
-/*
- * This file is part of ViaVersion - https://github.com/ViaVersion/ViaVersion
- * Copyright (C) 2016-2024 ViaVersion and contributors
- *
- * Permission is hereby granted, free of charge, to any person obtaining a copy
- * of this software and associated documentation files (the "Software"), to deal
- * in the Software without restriction, including without limitation the rights
- * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
- * copies of the Software, and to permit persons to whom the Software is
- * furnished to do so, subject to the following conditions:
- *
- * The above copyright notice and this permission notice shall be included in all
- * copies or substantial portions of the Software.
- *
- * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
- * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
- * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
- * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
- * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
- * SOFTWARE.
- */
-package com.viaversion.viaversion.api.minecraft.item.data;
-
-import com.viaversion.viaversion.api.type.Type;
-import com.viaversion.viaversion.api.type.Types;
-import io.netty.buffer.ByteBuf;
-import it.unimi.dsi.fastutil.objects.Object2ObjectMap;
-import it.unimi.dsi.fastutil.objects.Object2ObjectOpenHashMap;
-import java.util.Map;
-
-public record MapDecorations(Map<String, MapDecoration> decorations) {
-
-    public static final Type<MapDecorations> TYPE = new Type<>(MapDecorations.class) {
-        @Override
-        public MapDecorations read(final ByteBuf buffer) {
-            final Object2ObjectMap<String, MapDecoration> decorations = new Object2ObjectOpenHashMap<>();
-            final int size = Types.VAR_INT.readPrimitive(buffer);
-            for (int i = 0; i < size; i++) {
-                final String id = Types.STRING.read(buffer);
-                final MapDecoration decoration = MapDecoration.TYPE.read(buffer);
-                decorations.put(id, decoration);
-            }
-            return new MapDecorations(decorations);
-        }
-
-        @Override
-        public void write(final ByteBuf buffer, final MapDecorations value) {
-            Types.VAR_INT.writePrimitive(buffer, value.decorations.size());
-            for (final Map.Entry<String, MapDecoration> entry : value.decorations.entrySet()) {
-                Types.STRING.write(buffer, entry.getKey());
-                MapDecoration.TYPE.write(buffer, entry.getValue());
-            }
-        }
-    };
-}

api/src/main/java/com/viaversion/viaversion/api/platform/ViaPlatform.java

@@ -215,4 +215,13 @@ public interface ViaPlatform<T> {
      * @return whether the platform has a plugin/mod with the given name
      */
     boolean hasPlugin(String name);
+
+    /**
+     * Returns whether the platform might be reloading.
+     *
+     * @return whether the platform might be reloading
+     */
+    default boolean couldBeReloading() {
+        return true;
+    }
 }

api/src/main/java/com/viaversion/viaversion/api/platform/ViaServerProxyPlatform.java

@@ -30,4 +30,9 @@ public interface ViaServerProxyPlatform<T> extends ViaPlatform<T> {
      * @return protocol detector service
      */
     ProtocolDetectorService protocolDetectorService();
+
+    @Override
+    default boolean couldBeReloading() {
+        return false;
+    }
 }

api/src/main/java/com/viaversion/viaversion/api/protocol/ProtocolManager.java

@@ -25,6 +25,7 @@ package com.viaversion.viaversion.api.protocol;
 import com.google.common.collect.Range;
 import com.viaversion.viaversion.api.connection.UserConnection;
 import com.viaversion.viaversion.api.protocol.packet.ClientboundPacketType;
+import com.viaversion.viaversion.api.protocol.packet.Direction;
 import com.viaversion.viaversion.api.protocol.packet.PacketType;
 import com.viaversion.viaversion.api.protocol.packet.PacketWrapper;
 import com.viaversion.viaversion.api.protocol.packet.ServerboundPacketType;
@@ -73,13 +74,14 @@ public interface ProtocolManager {
     Protocol getBaseProtocol();
 
     /**
-     * Returns the base protocol for a specific server protocol version.
+     * Returns the base protocols for a specific server and client protocol version.
      * The standard base protocols deal with status and login packets for userconnection initialization.
      *
+     * @param clientVersion client protocol version
      * @param serverVersion server protocol version
-     * @return base protocol for the given server protocol version if present, else null
+     * @return base protocols for the given server and client protocol version
      */
-    @Nullable Protocol getBaseProtocol(ProtocolVersion serverVersion);
+    List<Protocol> getBaseProtocols(@Nullable ProtocolVersion clientVersion, @Nullable ProtocolVersion serverVersion);
 
     /**
      * Returns an immutable collection of registered protocols.
@@ -120,11 +122,12 @@ public interface ProtocolManager {
      * Registers and initializes a base protocol. Base Protocols registered later have higher priority.
      * Only base protocol will always be added to pipeline.
      *
+     * @param direction          direction of the base protocol
      * @param baseProtocol       base protocol to register
      * @param supportedProtocols protocol versions supported by the base protocol
      * @throws IllegalArgumentException if the protocol is not a base protocol as given by {@link Protocol#isBaseProtocol()}
      */
-    void registerBaseProtocol(Protocol baseProtocol, Range<ProtocolVersion> supportedProtocols);
+    void registerBaseProtocol(Direction direction, Protocol baseProtocol, Range<ProtocolVersion> supportedProtocols);
 
     /**
      * Calculates and returns the protocol path from a client protocol version to server protocol version.

api/src/main/java/com/viaversion/viaversion/api/protocol/packet/PacketWrapper.java

@@ -145,6 +145,18 @@ public interface PacketWrapper {
      */
     <T> T passthrough(Type<T> type) throws InformativeException;
 
+    /**
+     * Take a value from the input and write to the output, mapping the output type.
+     * This only works for types implementing {@link com.viaversion.viaversion.api.type.TypeConverter}, which is generally only the primitive wrapper types.
+     *
+     * @param type       The type to read.
+     * @param mappedType The type to write.
+     * @param <T>        The return type of the type you wish to pass through.
+     * @return The type which was read/written.
+     * @throws InformativeException If it failed to read or write
+     */
+    <T> T passthroughAndMap(Type<?> type, Type<T> mappedType) throws InformativeException;
+
     /**
      * Take all the inputs and write them to the output.
      *
@@ -224,6 +236,14 @@ public interface PacketWrapper {
      */
     void sendRaw() throws InformativeException;
 
+    /**
+     * Sends this packet to the associated user, submitted to netty's event loop.
+     * <b>Unlike {@link #sendFuture(Class)}, this method does not handle the pipeline with packet id and data changes.</b>
+     *
+     * @throws InformativeException if it fails to write
+     */
+    ChannelFuture sendFutureRaw() throws InformativeException;
+
     /**
      * Sends this packet to the associated user, submitted to netty's event loop.
      * <b>Unlike {@link #send(Class)}, this method does not handle the pipeline with packet id and data changes.</b>

api/src/main/java/com/viaversion/viaversion/api/protocol/remapper/PacketHandlers.java

@@ -54,7 +54,7 @@ public abstract class PacketHandlers implements PacketHandler {
      * @param type type to map
      */
     public <T> void map(Type<T> type) {
-        handler(wrapper -> wrapper.write(type, wrapper.read(type)));
+        handler(wrapper -> wrapper.passthrough(type));
     }
 
     /**
@@ -63,8 +63,8 @@ public abstract class PacketHandlers implements PacketHandler {
      * @param oldType old type
      * @param newType new type
      */
-    public void map(Type oldType, Type newType) {
-        handler(wrapper -> wrapper.write(newType, wrapper.read(oldType)));
+    public void map(Type<?> oldType, Type<?> newType) {
+        handler(wrapper -> wrapper.passthroughAndMap(oldType, newType));
     }
 
     /**

api/src/main/java/com/viaversion/viaversion/api/protocol/version/ProtocolVersion.java

@@ -84,7 +84,7 @@ public class ProtocolVersion implements Comparable<ProtocolVersion> {
     public static final ProtocolVersion v1_20_2 = register(764, "1.20.2");
     public static final ProtocolVersion v1_20_3 = register(765, "1.20.3-1.20.4", new SubVersionRange("1.20", 3, 4));
     public static final ProtocolVersion v1_20_5 = register(766, "1.20.5-1.20.6", new SubVersionRange("1.20", 5, 6));
-    public static final ProtocolVersion v1_21 = register(767, "1.21");
+    public static final ProtocolVersion v1_21 = register(767, "1.21-1.21.1", new SubVersionRange("1.21", 0, 1));
     public static final ProtocolVersion unknown = new ProtocolVersion(VersionType.SPECIAL, -1, -1, "UNKNOWN", null);
 
     public static ProtocolVersion register(int version, String name) {

api/src/main/java/com/viaversion/viaversion/api/protocol/version/VersionProvider.java

@@ -28,6 +28,31 @@ import com.viaversion.viaversion.api.platform.providers.Provider;
 @FunctionalInterface
 public interface VersionProvider extends Provider {
 
+    /**
+     * Optionally allows platforms to specify the client version of a user. This is needed when the platform supports
+     * connecting other version types then {@link VersionType#RELEASE} to the server.
+     *
+     * @param connection connection
+     * @return client protocol version, or null if handshake packet should be used
+     */
+    default ProtocolVersion getClientProtocol(UserConnection connection) {
+        return null;
+    }
+
+    /**
+     * Calls {@link #getClosestServerProtocol(UserConnection)} and catches any exceptions by returning null.
+     *
+     * @param connection connection
+     * @return closest server protocol version to the user's protocol version
+     */
+    default ProtocolVersion getServerProtocol(UserConnection connection) {
+        try {
+            return getClosestServerProtocol(connection);
+        } catch (Exception e) {
+            return null;
+        }
+    }
+
     /**
      * Returns the closest server protocol version to the user's protocol version.
      * On non-proxy servers, this returns the actual server version.

api/src/main/java/com/viaversion/viaversion/api/rewriter/EntityRewriter.java

@@ -59,13 +59,13 @@ public interface EntityRewriter<T extends Protocol<?, ?, ?, ?>> extends Rewriter
     int newEntityId(int id);
 
     /**
-     * Handles and transforms metadata of an entity.
+     * Handles and transforms entity data of an entity.
      *
      * @param entityId     entity id
-     * @param metadataList full, mutable list of metadata
+     * @param dataList full, mutable list of entity data
      * @param connection   user connection
      */
-    void handleEntityData(int entityId, List<EntityData> metadataList, UserConnection connection);
+    void handleEntityData(int entityId, List<EntityData> dataList, UserConnection connection);
 
     /**
      * Returns the entity tracker for the current protocol.

api/src/main/java/com/viaversion/viaversion/api/type/types/ComponentType.java

@@ -44,7 +44,9 @@ public class ComponentType extends Type<JsonElement> {
         try {
             return JsonParser.parseString(s);
         } catch (JsonSyntaxException e) {
-            Via.getPlatform().getLogger().severe("Error when trying to parse json: " + s);
+            if (Via.getManager().isDebug()) {
+                Via.getPlatform().getLogger().severe("Error when trying to parse json: " + s);
+            }
             throw e;
         }
     }

api/src/main/java/com/viaversion/viaversion/api/type/types/entitydata/EntityDataListType.java

@@ -40,20 +40,20 @@ public final class EntityDataListType extends EntityDataListTypeTemplate {
     @Override
     public List<EntityData> read(final ByteBuf buffer) {
         final List<EntityData> list = new ArrayList<>();
-        EntityData meta;
+        EntityData data;
         do {
-            meta = this.type.read(buffer);
-            if (meta != null) {
-                list.add(meta);
+            data = this.type.read(buffer);
+            if (data != null) {
+                list.add(data);
             }
-        } while (meta != null);
+        } while (data != null);
         return list;
     }
 
     @Override
     public void write(final ByteBuf buffer, final List<EntityData> object) {
-        for (final EntityData metadata : object) {
-            this.type.write(buffer, metadata);
+        for (final EntityData data : object) {
+            this.type.write(buffer, data);
         }
         this.type.write(buffer, null);
     }

api/src/main/java/com/viaversion/viaversion/api/type/types/entitydata/EntityDataType.java

@@ -26,14 +26,14 @@ import com.viaversion.viaversion.api.minecraft.entitydata.types.EntityDataTypes;
 
 public final class EntityDataType extends ModernEntityDataType {
 
-    private final EntityDataTypes metaTypes;
+    private final EntityDataTypes dataTypes;
 
-    public EntityDataType(final EntityDataTypes metaTypes) {
-        this.metaTypes = metaTypes;
+    public EntityDataType(final EntityDataTypes dataTypes) {
+        this.dataTypes = dataTypes;
     }
 
     @Override
     protected com.viaversion.viaversion.api.minecraft.entitydata.EntityDataType getType(final int index) {
-        return metaTypes.byId(index);
+        return dataTypes.byId(index);
     }
 }

api/src/main/java/com/viaversion/viaversion/api/type/types/entitydata/ModernEntityDataType.java

@@ -33,7 +33,7 @@ public abstract class ModernEntityDataType extends EntityDataTypeTemplate {
     @Override
     public EntityData read(final ByteBuf buffer) {
         final short index = buffer.readUnsignedByte();
-        if (index == END) return null; // End of metadata
+        if (index == END) return null; // End of data
         final EntityDataType type = this.getType(Types.VAR_INT.readPrimitive(buffer));
         return new EntityData(index, type, type.type().read(buffer));
     }

api/src/main/java/com/viaversion/viaversion/api/type/types/entitydata/OldEntityDataType.java

@@ -32,7 +32,7 @@ public abstract class OldEntityDataType extends EntityDataTypeTemplate {
     @Override
     public EntityData read(final ByteBuf buffer) {
         final byte index = buffer.readByte();
-        if (index == END) return null; // End of metadata
+        if (index == END) return null; // End of data
         final EntityDataType type = this.getType((index & 224) >> 5);
         return new EntityData(index & 31, type, type.type().read(buffer));
     }

api/src/main/java/com/viaversion/viaversion/api/type/types/item/StructuredDataType.java

@@ -50,7 +50,7 @@ public class StructuredDataType extends Type<StructuredData<?>> {
     public StructuredData<?> read(final ByteBuf buffer) {
         Preconditions.checkNotNull(types, "StructuredDataType has not been initialized");
         final int id = Types.VAR_INT.readPrimitive(buffer);
-        final StructuredDataKey<?> key = this.types[id];
+        final StructuredDataKey<?> key = key(id);
         if (key == null) {
             throw new IllegalArgumentException("No data component serializer found for id " + id);
         }

api/src/main/java/com/viaversion/viaversion/api/type/types/version/Types1_12.java

@@ -31,11 +31,11 @@ import java.util.List;
 public final class Types1_12 {
 
     /**
-     * Metadata type for 1.12
+     * Entity data type for 1.12
      */
     public static final Type<EntityData> ENTITY_DATA = new EntityDataType1_12();
     /**
-     * Metadata list type for 1.12
+     * Entity data list type for 1.12
      */
     public static final Type<List<EntityData>> ENTITY_DATA_LIST = new EntityDataListType(ENTITY_DATA);
 }

api/src/main/java/com/viaversion/viaversion/api/type/types/version/Types1_8.java

@@ -33,11 +33,11 @@ import java.util.List;
 public final class Types1_8 {
 
     /**
-     * Metadata type for 1.8
+     * Entity data type for 1.8
      */
     public static final Type<EntityData> ENTITY_DATA = new EntityDataType1_8();
     /**
-     * Metadata list type for 1.8
+     * Entity data list type for 1.8
      */
     public static final Type<List<EntityData>> ENTITY_DATA_LIST = new EntityDataListType(ENTITY_DATA);
 

api/src/main/java/com/viaversion/viaversion/api/type/types/version/Types1_9.java

@@ -32,11 +32,11 @@ import java.util.List;
 
 public final class Types1_9 {
     /**
-     * Metadata type for 1.9
+     * Entity data type for 1.9
      */
     public static final Type<EntityData> ENTITY_DATA = new EntityDataType1_9();
     /**
-     * Metadata list type for 1.9
+     * Entity data list type for 1.9
      */
     public static final Type<List<EntityData>> ENTITY_DATA_LIST = new EntityDataListType(ENTITY_DATA);
 

build-logic/build.gradle.kts

@@ -8,5 +8,5 @@ repositories {
 
 dependencies {
     // version must be manually kept in sync with the one in root project settings.gradle.kts
-    implementation("com.github.johnrengelman", "shadow", "8.1.1")
+    implementation("com.gradleup.shadow", "shadow-gradle-plugin", "8.3.0")
 }

build-logic/src/main/kotlin/via.base-conventions.gradle.kts

@@ -5,7 +5,7 @@ plugins {
 tasks {
     // Variable replacements
     processResources {
-        filesMatching(listOf("plugin.yml", "fabric.mod.json")) {
+        filesMatching(listOf("plugin.yml", "META-INF/sponge_plugins.json", "fabric.mod.json")) {
             expand("version" to project.version, "description" to project.description, "url" to "https://viaversion.com")
         }
     }

build-logic/src/main/kotlin/via.shadow-conventions.gradle.kts

@@ -4,7 +4,7 @@ import org.gradle.jvm.tasks.Jar
 plugins {
     id("via.base-conventions")
     id("maven-publish")
-    id("com.github.johnrengelman.shadow")
+    id("com.gradleup.shadow")
 }
 
 tasks {
@@ -45,6 +45,7 @@ fun ShadowJar.configureRelocations() {
     relocate("com.google.gson", "com.viaversion.viaversion.libs.gson")
     relocate("it.unimi.dsi.fastutil", "com.viaversion.viaversion.libs.fastutil")
     relocate("net.lenni0451.mcstructs", "com.viaversion.viaversion.libs.mcstructs")
+    relocate("org.yaml.snakeyaml", "com.viaversion.viaversion.libs.snakeyaml")
 }
 
 fun ShadowJar.configureExcludes() {

build.gradle.kts

@@ -6,7 +6,7 @@ plugins {
 allprojects {
     group = "com.viaversion"
     version = property("projectVersion") as String // from gradle.properties
-    description = "Allow newer clients to join older server versions."
+    description = "Allows the connection of newer clients to older server versions for Minecraft servers."
 }
 
 val main = setOf(

bukkit-legacy/src/main/java/com/viaversion/viaversion/bukkit/listeners/v1_8to1_9/ArmorListener.java

@@ -15,7 +15,7 @@
  * 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.bukkit.listeners.protocol1_9to1_8;
+package com.viaversion.viaversion.bukkit.listeners.v1_8to1_9;
 
 import com.viaversion.viaversion.api.Via;
 import com.viaversion.viaversion.api.protocol.packet.PacketWrapper;
@@ -117,4 +117,4 @@ public class ArmorListener extends ViaBukkitListener {
         if (!isOnPipe(player)) return; // Don't start a task if the player is not on the pipe
         Via.getPlatform().runSync(() -> sendArmorUpdate(player));
     }
-}
+}

bukkit-legacy/src/main/java/com/viaversion/viaversion/bukkit/listeners/v1_8to1_9/BlockListener.java

@@ -15,7 +15,7 @@
  * 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.bukkit.listeners.protocol1_9to1_8;
+package com.viaversion.viaversion.bukkit.listeners.v1_8to1_9;
 
 import com.viaversion.viaversion.api.minecraft.BlockPosition;
 import com.viaversion.viaversion.bukkit.listeners.ViaBukkitListener;

bukkit-legacy/src/main/java/com/viaversion/viaversion/bukkit/listeners/v1_8to1_9/DeathListener.java

@@ -15,7 +15,7 @@
  * 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.bukkit.listeners.protocol1_9to1_8;
+package com.viaversion.viaversion.bukkit.listeners.v1_8to1_9;
 
 import com.viaversion.viaversion.api.Via;
 import com.viaversion.viaversion.api.connection.UserConnection;

bukkit-legacy/src/main/java/com/viaversion/viaversion/bukkit/listeners/v1_8to1_9/HandItemCache.java

@@ -15,7 +15,7 @@
  * 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.bukkit.listeners.protocol1_9to1_8;
+package com.viaversion.viaversion.bukkit.listeners.v1_8to1_9;
 
 import com.viaversion.viaversion.api.minecraft.item.DataItem;
 import com.viaversion.viaversion.api.minecraft.item.Item;

bukkit-legacy/src/main/java/com/viaversion/viaversion/bukkit/listeners/v1_8to1_9/PaperPatch.java

@@ -15,7 +15,7 @@
  * 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.bukkit.listeners.protocol1_9to1_8;
+package com.viaversion.viaversion.bukkit.listeners.v1_8to1_9;
 
 import com.viaversion.viaversion.bukkit.listeners.ViaBukkitListener;
 import com.viaversion.viaversion.bukkit.util.CollisionChecker;

bukkit/src/main/java/com/viaversion/viaversion/ViaVersionPlugin.java

@@ -268,6 +268,11 @@ public class ViaVersionPlugin extends JavaPlugin implements ViaPlatform<Player>
         return getServer().getPluginManager().getPlugin(name) != null;
     }
 
+    @Override
+    public boolean couldBeReloading() {
+        return !(PaperViaInjector.PAPER_IS_STOPPING_METHOD && Bukkit.isStopping());
+    }
+
     public boolean isLateBind() {
         return lateBind;
     }

bukkit/src/main/java/com/viaversion/viaversion/bukkit/listeners/JoinListener.java

@@ -112,7 +112,10 @@ public class JoinListener implements Listener {
             return;
         }
         // The connection has already closed, that was a quick leave
-        if (!channel.isOpen()) return;
+        // Channel may be null if a plugin is manually calling the event for a non-player...
+        if (channel == null || !channel.isOpen()) {
+            return;
+        }
 
         UserConnection user = getUserConnection(channel);
         if (user == null) {

bukkit/src/main/java/com/viaversion/viaversion/bukkit/listeners/v1_14_4to1_15/EntityToggleGlideListener.java

@@ -51,13 +51,13 @@ public class EntityToggleGlideListener extends ViaBukkitListener {
 
         if (!isOnPipe(player)) return;
 
-        // Cancelling can only be done by updating the player's metadata
+        // Cancelling can only be done by updating the player's entity data
         if (event.isGliding() && event.isCancelled()) {
             PacketWrapper packet = PacketWrapper.create(ClientboundPackets1_15.SET_ENTITY_DATA, null, getUserConnection(player));
             packet.write(Types.VAR_INT, player.getEntityId());
 
             byte bitmask = 0;
-            // Collect other metadata for the mitmask
+            // Collect other entity data for the mitmask
             if (player.getFireTicks() > 0) {
                 bitmask |= 0x01;
             }

bukkit/src/main/java/com/viaversion/viaversion/bukkit/listeners/v1_20_5to1_21/PaperPlayerChangeItemListener.java

@@ -0,0 +1,51 @@
+/*
+ * This file is part of ViaVersion - https://github.com/ViaVersion/ViaVersion
+ * Copyright (C) 2016-2024 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.bukkit.listeners.v1_20_5to1_21;
+
+import com.viaversion.viaversion.ViaVersionPlugin;
+import io.papermc.paper.event.player.PlayerInventorySlotChangeEvent;
+import org.bukkit.entity.Player;
+import org.bukkit.event.EventHandler;
+import org.bukkit.event.EventPriority;
+import org.bukkit.inventory.ItemStack;
+import org.bukkit.inventory.PlayerInventory;
+
+public final class PaperPlayerChangeItemListener extends PlayerChangeItemListener {
+
+    public PaperPlayerChangeItemListener(final ViaVersionPlugin plugin) {
+        super(plugin);
+    }
+
+    @EventHandler(priority = EventPriority.MONITOR, ignoreCancelled = true)
+    public void onPlayerInventorySlotChangedEvent(final PlayerInventorySlotChangeEvent event) {
+        final Player player = event.getPlayer();
+        final ItemStack item = event.getNewItemStack();
+        final PlayerInventory inventory = player.getInventory();
+        final int slot = event.getSlot();
+        if (slot == inventory.getHeldItemSlot()) {
+            sendAttributeUpdate(player, item, Slot.HAND);
+        } else if (slot == 36) {
+            sendAttributeUpdate(player, item, Slot.BOOTS);
+        } else if (slot == 37) {
+            sendAttributeUpdate(player, item, Slot.LEGGINGS);
+        } else if (slot == 39) {
+            sendAttributeUpdate(player, item, Slot.HELMET);
+        }
+    }
+
+}

bukkit/src/main/java/com/viaversion/viaversion/bukkit/listeners/v1_20_5to1_21/PlayerChangeItemListener.java

@@ -23,50 +23,31 @@ import com.viaversion.viaversion.api.connection.UserConnection;
 import com.viaversion.viaversion.bukkit.listeners.ViaBukkitListener;
 import com.viaversion.viaversion.protocols.v1_20_5to1_21.Protocol1_20_5To1_21;
 import com.viaversion.viaversion.protocols.v1_20_5to1_21.storage.EfficiencyAttributeStorage;
-import io.papermc.paper.event.player.PlayerInventorySlotChangeEvent;
-import org.bukkit.NamespacedKey;
 import org.bukkit.enchantments.Enchantment;
 import org.bukkit.entity.Player;
 import org.bukkit.event.EventHandler;
 import org.bukkit.event.EventPriority;
 import org.bukkit.event.player.PlayerItemHeldEvent;
 import org.bukkit.inventory.ItemStack;
-import org.bukkit.inventory.PlayerInventory;
 import org.checkerframework.checker.nullness.qual.Nullable;
 
 /**
  * For some reason, mining efficiency is not calculated by the client anymore, but by the server,
  * then sending the current value to the client every time the item changes. This roughly emulates that behavior.
  */
-public final class PlayerChangeItemListener extends ViaBukkitListener {
+public class PlayerChangeItemListener extends ViaBukkitListener {
 
-    private final Enchantment efficiency = Enchantment.getByKey(NamespacedKey.minecraft("efficiency"));
-    private final Enchantment aquaAffinity = Enchantment.getByKey(NamespacedKey.minecraft("aqua_affinity"));
-    private final Enchantment depthStrider = Enchantment.getByKey(NamespacedKey.minecraft("depth_strider"));
-    private final Enchantment soulSpeed = Enchantment.getByKey(NamespacedKey.minecraft("soul_speed"));
-    private final Enchantment swiftSneak = Enchantment.getByKey(NamespacedKey.minecraft("swift_sneak"));
+    // Use legacy function and names here to support all versions
+    private final Enchantment efficiency = getByName("efficiency", "DIG_SPEED");
+    private final Enchantment aquaAffinity = getByName("aqua_affinity", "WATER_WORKER");
+    private final Enchantment depthStrider = getByName("depth_strider", "DEPTH_STRIDER");
+    private final Enchantment soulSpeed = getByName("soul_speed", "SOUL_SPEED");
+    private final Enchantment swiftSneak = getByName("swift_sneak", "SWIFT_SNEAK");
 
     public PlayerChangeItemListener(final ViaVersionPlugin plugin) {
         super(plugin, Protocol1_20_5To1_21.class);
     }
 
-    @EventHandler(priority = EventPriority.MONITOR, ignoreCancelled = true)
-    public void onPlayerInventorySlotChangedEvent(final PlayerInventorySlotChangeEvent event) {
-        final Player player = event.getPlayer();
-        final ItemStack item = event.getNewItemStack();
-        final PlayerInventory inventory = player.getInventory();
-        final int slot = event.getSlot();
-        if (slot == inventory.getHeldItemSlot()) {
-            sendAttributeUpdate(player, item, Slot.HAND);
-        } else if (slot == 36) {
-            sendAttributeUpdate(player, item, Slot.BOOTS);
-        } else if (slot == 37) {
-            sendAttributeUpdate(player, item, Slot.LEGGINGS);
-        } else if (slot == 39) {
-            sendAttributeUpdate(player, item, Slot.HELMET);
-        }
-    }
-
     @EventHandler(priority = EventPriority.MONITOR, ignoreCancelled = true)
     public void onPlayerItemHeld(final PlayerItemHeldEvent event) {
         final Player player = event.getPlayer();
@@ -74,7 +55,7 @@ public final class PlayerChangeItemListener extends ViaBukkitListener {
         sendAttributeUpdate(player, item, Slot.HAND);
     }
 
-    private void sendAttributeUpdate(final Player player, @Nullable final ItemStack item, final Slot slot) {
+    void sendAttributeUpdate(final Player player, @Nullable final ItemStack item, final Slot slot) {
         final UserConnection connection = Via.getAPI().getConnection(player.getUniqueId());
         if (connection == null || !isOnPipe(player)) {
             return;
@@ -105,7 +86,15 @@ public final class PlayerChangeItemListener extends ViaBukkitListener {
         storage.setEnchants(player.getEntityId(), connection, efficiencyLevel, soulSpeedLevel, swiftSneakLevel, aquaAffinityLevel, depthStriderLevel);
     }
 
-    private enum Slot {
+    enum Slot {
         HAND, BOOTS, LEGGINGS, HELMET
     }
+
+    private Enchantment getByName(final String newName, final String oldName) {
+        final Enchantment enchantment = Enchantment.getByName(newName);
+        if (enchantment == null) {
+            return Enchantment.getByName(oldName);
+        }
+        return enchantment;
+    }
 }

bukkit/src/main/java/com/viaversion/viaversion/bukkit/platform/BukkitViaConfig.java

@@ -19,19 +19,20 @@ package com.viaversion.viaversion.bukkit.platform;
 
 import com.viaversion.viaversion.configuration.AbstractViaConfig;
 import java.io.File;
-import java.util.Arrays;
 import java.util.List;
 import java.util.Map;
 import java.util.logging.Logger;
 
 public class BukkitViaConfig extends AbstractViaConfig {
-    private static final List<String> UNSUPPORTED = Arrays.asList("velocity-ping-interval", "velocity-ping-save", "velocity-servers");
     private boolean quickMoveActionFix;
     private boolean hitboxFix1_9;
     private boolean hitboxFix1_14;
     private String blockConnectionMethod;
     private boolean armorToggleFix;
     private boolean registerUserConnectionOnJoin;
+    private boolean useNewDeathMessages;
+    private boolean itemCache;
+    private boolean nmsPlayerTicking;
 
     public BukkitViaConfig(final File folder, final Logger logger) {
         super(new File(folder, "config.yml"), logger);
@@ -46,6 +47,9 @@ public class BukkitViaConfig extends AbstractViaConfig {
         hitboxFix1_14 = getBoolean("change-1_14-hitbox", false);
         blockConnectionMethod = getString("blockconnection-method", "packet");
         armorToggleFix = getBoolean("armor-toggle-fix", true);
+        useNewDeathMessages = getBoolean("use-new-deathmessages", true);
+        itemCache = getBoolean("item-cache", true);
+        nmsPlayerTicking = getBoolean("nms-player-ticking", true);
     }
 
     @Override
@@ -82,8 +86,23 @@ public class BukkitViaConfig extends AbstractViaConfig {
         return armorToggleFix;
     }
 
+    @Override
+    public boolean isShowNewDeathMessages() {
+        return useNewDeathMessages;
+    }
+
+    @Override
+    public boolean isItemCache() {
+        return itemCache;
+    }
+
+    @Override
+    public boolean isNMSPlayerTicking() {
+        return nmsPlayerTicking;
+    }
+
     @Override
     public List<String> getUnsupportedOptions() {
-        return UNSUPPORTED;
+        return VELOCITY_ONLY_OPTIONS;
     }
 }

bukkit/src/main/java/com/viaversion/viaversion/bukkit/platform/BukkitViaLoader.java

@@ -28,11 +28,12 @@ import com.viaversion.viaversion.bukkit.listeners.multiversion.PlayerSneakListen
 import com.viaversion.viaversion.bukkit.listeners.v1_14_4to1_15.EntityToggleGlideListener;
 import com.viaversion.viaversion.bukkit.listeners.v1_19_3to1_19_4.ArmorToggleListener;
 import com.viaversion.viaversion.bukkit.listeners.v1_18_2to1_19.BlockBreakListener;
-import com.viaversion.viaversion.bukkit.listeners.protocol1_9to1_8.ArmorListener;
-import com.viaversion.viaversion.bukkit.listeners.protocol1_9to1_8.BlockListener;
-import com.viaversion.viaversion.bukkit.listeners.protocol1_9to1_8.DeathListener;
-import com.viaversion.viaversion.bukkit.listeners.protocol1_9to1_8.HandItemCache;
-import com.viaversion.viaversion.bukkit.listeners.protocol1_9to1_8.PaperPatch;
+import com.viaversion.viaversion.bukkit.listeners.v1_8to1_9.ArmorListener;
+import com.viaversion.viaversion.bukkit.listeners.v1_8to1_9.BlockListener;
+import com.viaversion.viaversion.bukkit.listeners.v1_8to1_9.DeathListener;
+import com.viaversion.viaversion.bukkit.listeners.v1_8to1_9.HandItemCache;
+import com.viaversion.viaversion.bukkit.listeners.v1_8to1_9.PaperPatch;
+import com.viaversion.viaversion.bukkit.listeners.v1_20_5to1_21.PaperPlayerChangeItemListener;
 import com.viaversion.viaversion.bukkit.listeners.v1_20_5to1_21.PlayerChangeItemListener;
 import com.viaversion.viaversion.bukkit.providers.BukkitAckSequenceProvider;
 import com.viaversion.viaversion.bukkit.providers.BukkitBlockConnectionProvider;
@@ -87,7 +88,9 @@ public class BukkitViaLoader implements ViaPlatformLoader {
         if (serverProtocolVersion.olderThan(ProtocolVersion.v1_9)) {
             new ArmorListener(plugin).register();
             new DeathListener(plugin).register();
-            new BlockListener(plugin).register();
+            if (plugin.getConf().cancelBlockSounds()) {
+                new BlockListener(plugin).register();
+            }
 
             if (plugin.getConf().isItemCache()) {
                 handItemCache = new HandItemCache();
@@ -177,8 +180,12 @@ public class BukkitViaLoader implements ViaPlatformLoader {
             Via.getManager().getProviders().use(AckSequenceProvider.class, new BukkitAckSequenceProvider(plugin));
             new BlockBreakListener(plugin).register();
         }
-        if (serverProtocolVersion.olderThan(ProtocolVersion.v1_21) && PaperViaInjector.hasClass("io.papermc.paper.event.player.PlayerInventorySlotChangeEvent")) {
-            new PlayerChangeItemListener(plugin).register();
+        if (serverProtocolVersion.olderThan(ProtocolVersion.v1_21)) {
+            if (PaperViaInjector.hasClass("io.papermc.paper.event.player.PlayerInventorySlotChangeEvent")) {
+                new PaperPlayerChangeItemListener(plugin).register();
+            } else {
+                new PlayerChangeItemListener(plugin).register();
+            }
         }
     }
 

bukkit/src/main/java/com/viaversion/viaversion/bukkit/platform/PaperViaInjector.java

@@ -28,6 +28,7 @@ public final class PaperViaInjector {
     public static final boolean PAPER_INJECTION_METHOD = hasPaperInjectionMethod();
     public static final boolean PAPER_PROTOCOL_METHOD = hasServerProtocolMethod();
     public static final boolean PAPER_PACKET_LIMITER = hasPacketLimiter();
+    public static final boolean PAPER_IS_STOPPING_METHOD = hasIsStoppingMethod();
 
     private PaperViaInjector() {
     }
@@ -76,6 +77,15 @@ public final class PaperViaInjector {
         return hasClass("io.papermc.paper.network.ChannelInitializeListener");
     }
 
+    private static boolean hasIsStoppingMethod() {
+        try {
+            Bukkit.class.getDeclaredMethod("isStopping");
+            return true;
+        } catch (final NoSuchMethodException e) {
+            return false;
+        }
+    }
+
     private static boolean hasPacketLimiter() {
         return hasClass("com.destroystokyo.paper.PaperConfig$PacketLimit") || hasClass("io.papermc.paper.configuration.GlobalConfiguration$PacketLimiter");
     }

bukkit/src/main/java/com/viaversion/viaversion/bukkit/providers/BukkitAckSequenceProvider.java

@@ -20,7 +20,7 @@ package com.viaversion.viaversion.bukkit.providers;
 import com.viaversion.viaversion.ViaVersionPlugin;
 import com.viaversion.viaversion.api.connection.UserConnection;
 import com.viaversion.viaversion.api.protocol.version.ProtocolVersion;
-import com.viaversion.viaversion.bukkit.tasks.protocol1_19to1_18_2.AckSequenceTask;
+import com.viaversion.viaversion.bukkit.tasks.v1_18_2to1_19.AckSequenceTask;
 import com.viaversion.viaversion.protocols.v1_18_2to1_19.provider.AckSequenceProvider;
 import com.viaversion.viaversion.protocols.v1_18_2to1_19.storage.SequenceStorage;
 
@@ -45,4 +45,4 @@ public final class BukkitAckSequenceProvider extends AckSequenceProvider {
             }
         }
     }
-}
+}

bukkit/src/main/java/com/viaversion/viaversion/bukkit/providers/BukkitInventoryQuickMoveProvider.java

@@ -21,7 +21,7 @@ import com.viaversion.viaversion.api.Via;
 import com.viaversion.viaversion.api.connection.ProtocolInfo;
 import com.viaversion.viaversion.api.connection.UserConnection;
 import com.viaversion.viaversion.api.protocol.version.ProtocolVersion;
-import com.viaversion.viaversion.bukkit.tasks.protocol1_12to1_11_1.BukkitInventoryUpdateTask;
+import com.viaversion.viaversion.bukkit.tasks.v1_11_1to1_12.BukkitInventoryUpdateTask;
 import com.viaversion.viaversion.bukkit.util.NMSUtil;
 import com.viaversion.viaversion.protocols.v1_11_1to1_12.provider.InventoryQuickMoveProvider;
 import com.viaversion.viaversion.protocols.v1_11_1to1_12.storage.ItemTransactionStorage;
@@ -201,4 +201,4 @@ public class BukkitInventoryQuickMoveProvider extends InventoryQuickMoveProvider
         final ProtocolVersion protocol = Via.getAPI().getServerVersion().lowestSupportedProtocolVersion();
         return protocol.newerThanOrEqualTo(ProtocolVersion.v1_8) && protocol.olderThanOrEqualTo(ProtocolVersion.v1_11_1);
     }
-}
+}

bukkit/src/main/java/com/viaversion/viaversion/bukkit/tasks/v1_11_1to1_12/BukkitInventoryUpdateTask.java

@@ -15,7 +15,7 @@
  * 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.bukkit.tasks.protocol1_12to1_11_1;
+package com.viaversion.viaversion.bukkit.tasks.v1_11_1to1_12;
 
 import com.viaversion.viaversion.bukkit.providers.BukkitInventoryQuickMoveProvider;
 import com.viaversion.viaversion.protocols.v1_11_1to1_12.storage.ItemTransactionStorage;
@@ -65,4 +65,4 @@ public class BukkitInventoryUpdateTask implements Runnable {
             provider.onTaskExecuted(uuid);
         }
     }
-}
+}

bukkit/src/main/java/com/viaversion/viaversion/bukkit/tasks/v1_18_2to1_19/AckSequenceTask.java

@@ -15,7 +15,7 @@
  * 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.bukkit.tasks.protocol1_19to1_18_2;
+package com.viaversion.viaversion.bukkit.tasks.v1_18_2to1_19;
 
 import com.viaversion.viaversion.api.Via;
 import com.viaversion.viaversion.api.connection.UserConnection;

common/build.gradle.kts

@@ -3,13 +3,11 @@ dependencies {
     api(rootProject.libs.text) {
         exclude("com.google.code.gson", "gson")
     }
-    implementation(projects.compat.snakeyaml2Compat)
-    implementation(projects.compat.snakeyaml1Compat)
 
     // Note: If manually starting tests doesn't work for you in IJ, change 'Gradle -> Run Tests Using' to 'IntelliJ IDEA'
     testImplementation(rootProject.libs.netty)
     testImplementation(rootProject.libs.guava)
-    testImplementation(rootProject.libs.snakeYaml2)
+    testImplementation(rootProject.libs.snakeYaml)
     testImplementation(rootProject.libs.bundles.junit)
 }
 

common/src/main/java/com/viaversion/viaversion/ViaManagerImpl.java

@@ -67,6 +67,7 @@ public class ViaManagerImpl implements ViaManager {
     private final ViaPlatformLoader loader;
     private final Set<String> subPlatforms = new HashSet<>();
     private List<Runnable> enableListeners = new ArrayList<>();
+    private List<Runnable> postEnableListeners = new ArrayList<>();
     private PlatformTask<?> mappingLoadingTask;
     private boolean initialized;
 
@@ -150,7 +151,7 @@ public class ViaManagerImpl implements ViaManager {
                 platform.getLogger().warning("and if you're still unsure, feel free to join our Discord-Server for further assistance.");
             } else if (protocolVersion.highestSupportedProtocolVersion().olderThan(ProtocolVersion.v1_13)) {
                 platform.getLogger().warning("This version of Minecraft is extremely outdated and support for it has reached its end of life. "
-                    + "You will still be able to run Via on this Minecraft version, but we are unlikely to provide any further fixes or help with problems specific to legacy Minecraft versions. "
+                    + "You will still be able to run Via on this Minecraft version, but we will prioritize issues with legacy Minecraft versions less. "
                     + "Please consider updating to give your players a better experience and to avoid issues that have long been fixed.");
             }
         }
@@ -184,6 +185,11 @@ public class ViaManagerImpl implements ViaManager {
 
         // Refresh Versions
         protocolManager.refreshVersions();
+
+        for (final Runnable listener : postEnableListeners) {
+            listener.run();
+        }
+        postEnableListeners = null;
     }
 
     private void loadServerProtocol() {
@@ -204,8 +210,10 @@ public class ViaManagerImpl implements ViaManager {
     }
 
     public void destroy() {
-        // Uninject
-        platform.getLogger().info("ViaVersion is disabling, if this is a reload and you experience issues consider rebooting.");
+        if (platform.couldBeReloading()) {
+            platform.getLogger().info("ViaVersion is disabling. If this is a reload and you experience issues, please reboot instead.");
+        }
+
         try {
             injector.uninject();
         } catch (Exception e) {
@@ -214,6 +222,8 @@ public class ViaManagerImpl implements ViaManager {
 
         loader.unload();
         scheduler.shutdown();
+
+        platform.getLogger().info("ViaVersion has been disabled; uninjected the platform and shut down the scheduler.");
     }
 
     private void checkJavaVersion() { // Stolen from Paper
@@ -235,7 +245,8 @@ public class ViaManagerImpl implements ViaManager {
 
         if (version < 17) {
             platform.getLogger().warning("You are running an outdated Java version, please update it to at least Java 17 (your version is " + javaVersion + ").");
-            platform.getLogger().warning("Starting with Minecraft 1.21, ViaVersion will no longer officially be compatible with this version of Java, only offering unsupported compatibility builds.");
+            platform.getLogger().warning("ViaVersion no longer officially supports this version of Java, only offering unsupported compatibility builds.");
+            platform.getLogger().warning("See https://github.com/ViaVersion/ViaVersion/releases/tag/5.0.0 for more information.");
         }
     }
 
@@ -316,25 +327,21 @@ public class ViaManagerImpl implements ViaManager {
         return configurationProvider;
     }
 
-    /**
-     * Returns a mutable set of self-added subplatform version strings.
-     * This set is expanded by the subplatform itself (e.g. ViaBackwards), and may not contain all running ones.
-     *
-     * @return mutable set of subplatform versions
-     */
+    @Override
     public Set<String> getSubPlatforms() {
         return subPlatforms;
     }
 
-    /**
-     * Adds a runnable to be executed when ViaVersion has finished its init before the full server load.
-     *
-     * @param runnable runnable to be executed
-     */
+    @Override
     public void addEnableListener(Runnable runnable) {
         enableListeners.add(runnable);
     }
 
+    @Override
+    public void addPostEnableListener(final Runnable runnable) {
+        postEnableListeners.add(runnable);
+    }
+
     @Override
     public boolean isInitialized() {
         return initialized;

common/src/main/java/com/viaversion/viaversion/commands/defaultsubs/DumpSubCmd.java

@@ -30,7 +30,7 @@ public class DumpSubCmd implements ViaSubCommand {
 
     @Override
     public String description() {
-        return "Dump information about your server, this is helpful if you report bugs.";
+        return "Dump information about your platform implementation, this is helpful if you report bugs.";
     }
 
     @Override

common/src/main/java/com/viaversion/viaversion/configuration/AbstractViaConfig.java

@@ -25,21 +25,26 @@ import com.viaversion.viaversion.api.protocol.version.BlockedProtocolVersions;
 import com.viaversion.viaversion.api.protocol.version.ProtocolVersion;
 import com.viaversion.viaversion.protocol.BlockedProtocolVersionsImpl;
 import com.viaversion.viaversion.util.Config;
+import it.unimi.dsi.fastutil.objects.ObjectOpenHashSet;
+import it.unimi.dsi.fastutil.objects.ObjectSet;
 import java.io.File;
+import java.util.Arrays;
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
 import java.util.logging.Logger;
-import it.unimi.dsi.fastutil.objects.ObjectOpenHashSet;
-import it.unimi.dsi.fastutil.objects.ObjectSet;
 import org.checkerframework.checker.nullness.qual.Nullable;
 
 public abstract class AbstractViaConfig extends Config implements ViaVersionConfig {
+    public static final List<String> BUKKIT_ONLY_OPTIONS = Arrays.asList("register-userconnections-on-join", "quick-move-action-fix",
+        "change-1_9-hitbox", "change-1_14-hitbox", "blockconnection-method", "armor-toggle-fix", "use-new-deathmessages",
+        "item-cache", "nms-player-ticking");
+
+    public static final List<String> VELOCITY_ONLY_OPTIONS = Arrays.asList("velocity-ping-interval", "velocity-ping-save", "velocity-servers");
 
     private boolean checkForUpdates;
     private boolean preventCollision;
     private boolean useNewEffectIndicator;
-    private boolean useNewDeathmessages;
     private boolean suppressMetadataErrors;
     private boolean shieldBlocking;
     private boolean noDelayShieldBlocking;
@@ -57,8 +62,6 @@ public abstract class AbstractViaConfig extends Config implements ViaVersionConf
     private String maxPPSWarningsKickMessage;
     private boolean sendSupportedVersions;
     private boolean simulatePlayerTick;
-    private boolean itemCache;
-    private boolean nmsPlayerTicking;
     private boolean replacePistons;
     private int pistonReplacementId;
     private boolean chunkBorderFix;
@@ -69,7 +72,6 @@ public abstract class AbstractViaConfig extends Config implements ViaVersionConf
     private String reloadDisconnectMessage;
     private boolean suppressConversionWarnings;
     private boolean disable1_13TabComplete;
-    private boolean minimizeCooldown;
     private boolean teamColourFix;
     private boolean serversideBlockConnections;
     private boolean reduceBlockStorageMemory;
@@ -91,6 +93,9 @@ public abstract class AbstractViaConfig extends Config implements ViaVersionConf
     private boolean translateOcelotToCat;
     private boolean enforceSecureChat;
     private boolean handleInvalidItemCount;
+    private boolean cancelBlockSounds;
+    private boolean hideScoreboardNumbers;
+    private boolean fix1_21PlacementRotation;
 
     protected AbstractViaConfig(final File configFile, final Logger logger) {
         super(configFile, logger);
@@ -106,7 +111,6 @@ public abstract class AbstractViaConfig extends Config implements ViaVersionConf
         checkForUpdates = getBoolean("check-for-updates", true);
         preventCollision = getBoolean("prevent-collision", true);
         useNewEffectIndicator = getBoolean("use-new-effect-indicator", true);
-        useNewDeathmessages = getBoolean("use-new-deathmessages", true);
         suppressMetadataErrors = getBoolean("suppress-metadata-errors", false);
         shieldBlocking = getBoolean("shield-blocking", true);
         noDelayShieldBlocking = getBoolean("no-delay-shield-blocking", false);
@@ -124,8 +128,6 @@ public abstract class AbstractViaConfig extends Config implements ViaVersionConf
         maxPPSWarningsKickMessage = getString("tracking-max-kick-msg", "You are sending too many packets, :(");
         sendSupportedVersions = getBoolean("send-supported-versions", false);
         simulatePlayerTick = getBoolean("simulate-pt", true);
-        itemCache = getBoolean("item-cache", true);
-        nmsPlayerTicking = getBoolean("nms-player-ticking", true);
         replacePistons = getBoolean("replace-pistons", false);
         pistonReplacementId = getInt("replacement-piston-id", 0);
         chunkBorderFix = getBoolean("chunk-border-fix", false);
@@ -134,7 +136,6 @@ public abstract class AbstractViaConfig extends Config implements ViaVersionConf
         blockedProtocolVersions = loadBlockedProtocolVersions();
         blockedDisconnectMessage = getString("block-disconnect-msg", "You are using an unsupported Minecraft version!");
         reloadDisconnectMessage = getString("reload-disconnect-msg", "Server reload, please rejoin!");
-        minimizeCooldown = getBoolean("minimize-cooldown", true);
         teamColourFix = getBoolean("team-colour-fix", true);
         suppressConversionWarnings = getBoolean("suppress-conversion-warnings", false);
         disable1_13TabComplete = getBoolean("disable-1_13-auto-complete", false);
@@ -161,6 +162,9 @@ public abstract class AbstractViaConfig extends Config implements ViaVersionConf
         translateOcelotToCat = getBoolean("translate-ocelot-to-cat", true);
         enforceSecureChat = getBoolean("enforce-secure-chat", false);
         handleInvalidItemCount = getBoolean("handle-invalid-item-count", false);
+        cancelBlockSounds = getBoolean("cancel-block-sounds", true);
+        hideScoreboardNumbers = getBoolean("hide-scoreboard-numbers", false);
+        fix1_21PlacementRotation = getBoolean("fix-1_21-placement-rotation", false);
     }
 
     private BlockedProtocolVersions loadBlockedProtocolVersions() {
@@ -254,7 +258,7 @@ public abstract class AbstractViaConfig extends Config implements ViaVersionConf
 
     @Override
     public boolean isShowNewDeathMessages() {
-        return useNewDeathmessages;
+        return false;
     }
 
     @Override
@@ -344,12 +348,12 @@ public abstract class AbstractViaConfig extends Config implements ViaVersionConf
 
     @Override
     public boolean isItemCache() {
-        return itemCache;
+        return false;
     }
 
     @Override
     public boolean isNMSPlayerTicking() {
-        return nmsPlayerTicking;
+        return false;
     }
 
     @Override
@@ -403,11 +407,6 @@ public abstract class AbstractViaConfig extends Config implements ViaVersionConf
         return reloadDisconnectMessage;
     }
 
-    @Override
-    public boolean isMinimizeCooldown() {
-        return minimizeCooldown;
-    }
-
     @Override
     public boolean is1_13TeamColourFix() {
         return teamColourFix;
@@ -542,4 +541,19 @@ public abstract class AbstractViaConfig extends Config implements ViaVersionConf
     public boolean handleInvalidItemCount() {
         return handleInvalidItemCount;
     }
+
+    @Override
+    public boolean cancelBlockSounds() {
+        return cancelBlockSounds;
+    }
+
+    @Override
+    public boolean hideScoreboardNumbers() {
+        return hideScoreboardNumbers;
+    }
+
+    @Override
+    public boolean fix1_21PlacementRotation() {
+        return fix1_21PlacementRotation;
+    }
 }

common/src/main/java/com/viaversion/viaversion/connection/UserConnectionImpl.java

@@ -23,6 +23,7 @@ import com.viaversion.viaversion.api.connection.ProtocolInfo;
 import com.viaversion.viaversion.api.connection.StorableObject;
 import com.viaversion.viaversion.api.connection.UserConnection;
 import com.viaversion.viaversion.api.data.entity.EntityTracker;
+import com.viaversion.viaversion.api.minecraft.ClientWorld;
 import com.viaversion.viaversion.api.platform.ViaInjector;
 import com.viaversion.viaversion.api.protocol.Protocol;
 import com.viaversion.viaversion.api.protocol.packet.Direction;
@@ -58,6 +59,7 @@ public class UserConnectionImpl implements UserConnection {
     private final long id = IDS.incrementAndGet();
     private final Map<Class<?>, StorableObject> storedObjects = new ConcurrentHashMap<>();
     private final Map<Class<? extends Protocol>, EntityTracker> entityTrackers = new HashMap<>();
+    private final Map<Class<? extends Protocol>, ClientWorld> clientWorlds = new HashMap<>();
     private final PacketTracker packetTracker = new PacketTracker(this);
     private final Set<UUID> passthroughTokens = Collections.newSetFromMap(CacheBuilder.newBuilder()
         .expireAfterWrite(10, TimeUnit.SECONDS)
@@ -125,9 +127,17 @@ public class UserConnectionImpl implements UserConnection {
 
     @Override
     public void addEntityTracker(Class<? extends Protocol> protocolClass, EntityTracker tracker) {
-        if (!entityTrackers.containsKey(protocolClass)) {
-            entityTrackers.put(protocolClass, tracker);
-        }
+        entityTrackers.putIfAbsent(protocolClass, tracker);
+    }
+
+    @Override
+    public @Nullable <T extends ClientWorld> T getClientWorld(final Class<? extends Protocol> protocolClass) {
+        return (T) clientWorlds.get(protocolClass);
+    }
+
+    @Override
+    public void addClientWorld(final Class<? extends Protocol> protocolClass, final ClientWorld clientWorld) {
+        clientWorlds.putIfAbsent(protocolClass, clientWorld);
     }
 
     @Override
@@ -142,7 +152,6 @@ public class UserConnectionImpl implements UserConnection {
             });
             for (EntityTracker tracker : entityTrackers.values()) {
                 tracker.clearEntities();
-                tracker.trackClientEntity();
             }
         } else {
             for (StorableObject object : storedObjects.values()) {
@@ -150,6 +159,7 @@ public class UserConnectionImpl implements UserConnection {
             }
             storedObjects.clear();
             entityTrackers.clear();
+            clientWorlds.clear();
         }
     }
 

common/src/main/java/com/viaversion/viaversion/data/entity/DimensionDataImpl.java

@@ -73,8 +73,9 @@ public final class DimensionDataImpl implements DimensionData {
 
     @Override
     public String toString() {
-        return "DimensionData{" +
-            "minY=" + minY +
+        return "DimensionDataImpl{" +
+            "id=" + id +
+            ", minY=" + minY +
             ", height=" + height +
             '}';
     }

common/src/main/java/com/viaversion/viaversion/data/entity/EntityTrackerBase.java

@@ -34,10 +34,10 @@ import java.util.Map;
 import org.checkerframework.checker.nullness.qual.Nullable;
 
 public class EntityTrackerBase implements EntityTracker, ClientEntityIdChangeListener {
-    private final Int2ObjectMap<TrackedEntity> entities = new Int2ObjectOpenHashMap<>();
+    protected final Int2ObjectMap<TrackedEntity> entities = new Int2ObjectOpenHashMap<>();
     private final UserConnection connection;
     private final EntityType playerType;
-    private int clientEntityId = -1;
+    private Integer clientEntityId;
     private int currentWorldSectionHeight = -1;
     private int currentMinY;
     private String currentWorld;
@@ -87,7 +87,6 @@ public class EntityTrackerBase implements EntityTracker, ClientEntityIdChangeLis
         return entity != null && entity.hasData() ? entity.data() : null;
     }
 
-    //TODO Soft memory leak: Remove entities on respawn in protocols prior to 1.18 (1.16+ only when the worldname is different)
     @Override
     public void removeEntity(int id) {
         entities.remove(id);
@@ -95,11 +94,27 @@ public class EntityTrackerBase implements EntityTracker, ClientEntityIdChangeLis
 
     @Override
     public void clearEntities() {
-        entities.clear();
+        // Call wrapper function in case protocols need to do additional removals
+        for (final int id : entities.keySet().toIntArray()) {
+            removeEntity(id);
+        }
+
+        // Re-add the client entity. Keep the call above to untrack attached data if necessary
+        if (clientEntityId != null) {
+            entities.put(clientEntityId.intValue(), new TrackedEntityImpl(playerType));
+        }
     }
 
     @Override
-    public int clientEntityId() {
+    public boolean hasClientEntityId() {
+        return clientEntityId != null;
+    }
+
+    @Override
+    public int clientEntityId() throws IllegalStateException {
+        if (clientEntityId == null) {
+            throw new IllegalStateException("Client entity id not set");
+        }
         return clientEntityId;
     }
 
@@ -107,7 +122,7 @@ public class EntityTrackerBase implements EntityTracker, ClientEntityIdChangeLis
     public void setClientEntityId(int clientEntityId) {
         Preconditions.checkNotNull(playerType);
         final TrackedEntity oldEntity;
-        if (this.clientEntityId != -1 && (oldEntity = entities.remove(this.clientEntityId)) != null) {
+        if (this.clientEntityId != null && (oldEntity = entities.remove(this.clientEntityId.intValue())) != null) {
             entities.put(clientEntityId, oldEntity);
         } else {
             entities.put(clientEntityId, new TrackedEntityImpl(playerType));
@@ -116,15 +131,6 @@ public class EntityTrackerBase implements EntityTracker, ClientEntityIdChangeLis
         this.clientEntityId = clientEntityId;
     }
 
-    @Override
-    public boolean trackClientEntity() {
-        if (clientEntityId != -1) {
-            entities.put(clientEntityId, new TrackedEntityImpl(playerType));
-            return true;
-        }
-        return false;
-    }
-
     @Override
     public int currentWorldSectionHeight() {
         return currentWorldSectionHeight;

common/src/main/java/com/viaversion/viaversion/dump/VersionInfo.java

@@ -17,10 +17,9 @@
  */
 package com.viaversion.viaversion.dump;
 
-import com.viaversion.viaversion.api.protocol.version.VersionType;
 import java.util.Set;
 
-public record VersionInfo(String javaVersion, String operatingSystem, VersionType versionType,
+public record VersionInfo(String javaVersion, String operatingSystem,
                           int serverProtocol, String serverVersion,
                           Set<String> enabledProtocols, String platformName,
                           String platformVersion, String pluginVersion,

common/src/main/java/com/viaversion/viaversion/legacy/bossbar/CommonBoss.java

@@ -19,6 +19,7 @@ package com.viaversion.viaversion.legacy.bossbar;
 
 import com.google.common.base.Preconditions;
 import com.google.common.collect.MapMaker;
+import com.google.gson.JsonParser;
 import com.viaversion.viaversion.api.Via;
 import com.viaversion.viaversion.api.connection.UserConnection;
 import com.viaversion.viaversion.api.legacy.bossbar.BossBar;
@@ -26,7 +27,6 @@ import com.viaversion.viaversion.api.legacy.bossbar.BossColor;
 import com.viaversion.viaversion.api.legacy.bossbar.BossFlag;
 import com.viaversion.viaversion.api.legacy.bossbar.BossStyle;
 import com.viaversion.viaversion.api.protocol.packet.PacketWrapper;
-import com.viaversion.viaversion.api.type.Type;
 import com.viaversion.viaversion.api.type.Types;
 import com.viaversion.viaversion.protocols.v1_8to1_9.Protocol1_8To1_9;
 import com.viaversion.viaversion.protocols.v1_8to1_9.packet.ClientboundPackets1_9;
@@ -246,28 +246,32 @@ public class CommonBoss implements BossBar {
             wrapper.write(Types.UUID, uuid);
             wrapper.write(Types.VAR_INT, action.getId());
             switch (action) {
-                case ADD:
-                    wrapper.write(Types.COMPONENT, ComponentUtil.plainToJson(title));
+                case ADD -> {
+                    try {
+                        wrapper.write(Types.COMPONENT, JsonParser.parseString(this.title));
+                    } catch (Exception e) {
+                        wrapper.write(Types.COMPONENT, ComponentUtil.plainToJson(this.title));
+                    }
                     wrapper.write(Types.FLOAT, health);
                     wrapper.write(Types.VAR_INT, color.getId());
                     wrapper.write(Types.VAR_INT, style.getId());
                     wrapper.write(Types.BYTE, (byte) flagToBytes());
-                    break;
-                case REMOVE:
-                    break;
-                case UPDATE_HEALTH:
-                    wrapper.write(Types.FLOAT, health);
-                    break;
-                case UPDATE_TITLE:
-                    wrapper.write(Types.COMPONENT, ComponentUtil.plainToJson(title));
-                    break;
-                case UPDATE_STYLE:
+                }
+                case REMOVE -> {
+                }
+                case UPDATE_HEALTH -> wrapper.write(Types.FLOAT, health);
+                case UPDATE_TITLE -> {
+                    try {
+                        wrapper.write(Types.COMPONENT, JsonParser.parseString(this.title));
+                    } catch (Exception e) {
+                        wrapper.write(Types.COMPONENT, ComponentUtil.plainToJson(this.title));
+                    }
+                }
+                case UPDATE_STYLE -> {
                     wrapper.write(Types.VAR_INT, color.getId());
                     wrapper.write(Types.VAR_INT, style.getId());
-                    break;
-                case UPDATE_FLAGS:
-                    wrapper.write(Types.BYTE, (byte) flagToBytes());
-                    break;
+                }
+                case UPDATE_FLAGS -> wrapper.write(Types.BYTE, (byte) flagToBytes());
             }
 
             return wrapper;

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

@@ -29,6 +29,7 @@ import com.viaversion.viaversion.api.protocol.ProtocolManager;
 import com.viaversion.viaversion.api.protocol.ProtocolPathEntry;
 import com.viaversion.viaversion.api.protocol.ProtocolPathKey;
 import com.viaversion.viaversion.api.protocol.packet.ClientboundPacketType;
+import com.viaversion.viaversion.api.protocol.packet.Direction;
 import com.viaversion.viaversion.api.protocol.packet.PacketType;
 import com.viaversion.viaversion.api.protocol.packet.PacketWrapper;
 import com.viaversion.viaversion.api.protocol.packet.ServerboundPacketType;
@@ -38,10 +39,9 @@ import com.viaversion.viaversion.api.protocol.version.ServerProtocolVersion;
 import com.viaversion.viaversion.api.protocol.version.VersionType;
 import com.viaversion.viaversion.protocol.packet.PacketWrapperImpl;
 import com.viaversion.viaversion.protocol.packet.VersionedPacketTransformerImpl;
-import com.viaversion.viaversion.protocols.base.BaseProtocol;
-import com.viaversion.viaversion.protocols.base.BaseProtocol1_16;
-import com.viaversion.viaversion.protocols.base.BaseProtocol1_7;
-import com.viaversion.viaversion.protocols.v1_20_5to1_21.Protocol1_20_5To1_21;
+import com.viaversion.viaversion.protocols.base.InitialBaseProtocol;
+import com.viaversion.viaversion.protocols.base.v1_7.ClientboundBaseProtocol1_7;
+import com.viaversion.viaversion.protocols.base.v1_7.ServerboundBaseProtocol1_7;
 import com.viaversion.viaversion.protocols.v1_10to1_11.Protocol1_10To1_11;
 import com.viaversion.viaversion.protocols.v1_11_1to1_12.Protocol1_11_1To1_12;
 import com.viaversion.viaversion.protocols.v1_11to1_11_1.Protocol1_11To1_11_1;
@@ -74,6 +74,7 @@ import com.viaversion.viaversion.protocols.v1_19_4to1_20.Protocol1_19_4To1_20;
 import com.viaversion.viaversion.protocols.v1_19to1_19_1.Protocol1_19To1_19_1;
 import com.viaversion.viaversion.protocols.v1_20_2to1_20_3.Protocol1_20_2To1_20_3;
 import com.viaversion.viaversion.protocols.v1_20_3to1_20_5.Protocol1_20_3To1_20_5;
+import com.viaversion.viaversion.protocols.v1_20_5to1_21.Protocol1_20_5To1_21;
 import com.viaversion.viaversion.protocols.v1_20to1_20_2.Protocol1_20To1_20_2;
 import com.viaversion.viaversion.protocols.v1_8to1_9.Protocol1_8To1_9;
 import com.viaversion.viaversion.protocols.v1_9_1to1_9_3.Protocol1_9_1To1_9_3;
@@ -109,14 +110,15 @@ import java.util.logging.Level;
 import org.checkerframework.checker.nullness.qual.Nullable;
 
 public class ProtocolManagerImpl implements ProtocolManager {
-    private static final Protocol BASE_PROTOCOL = new BaseProtocol();
+    private static final Protocol BASE_PROTOCOL = new InitialBaseProtocol();
 
     // Input Version -> Output Version & Protocol (Allows fast lookup)
     private final Object2ObjectMap<ProtocolVersion, Object2ObjectMap<ProtocolVersion, Protocol>> registryMap = new Object2ObjectOpenHashMap<>(32);
     private final Map<Class<? extends Protocol>, Protocol<?, ?, ?, ?>> protocols = new HashMap<>(64);
     private final Map<ProtocolPathKey, List<ProtocolPathEntry>> pathCache = new ConcurrentHashMap<>();
     private final Set<ProtocolVersion> supportedVersions = new HashSet<>();
-    private final List<Pair<Range<ProtocolVersion>, Protocol>> baseProtocols = Lists.newCopyOnWriteArrayList();
+    private final List<Pair<Range<ProtocolVersion>, Protocol>> serverboundBaseProtocols = Lists.newCopyOnWriteArrayList();
+    private final List<Pair<Range<ProtocolVersion>, Protocol>> clientboundBaseProtocols = Lists.newCopyOnWriteArrayList();
 
     private final ReadWriteLock mappingLoaderLock = new ReentrantReadWriteLock();
     private Map<Class<? extends Protocol>, CompletableFuture<Void>> mappingLoaderFutures = new HashMap<>();
@@ -137,8 +139,8 @@ public class ProtocolManagerImpl implements ProtocolManager {
         // Base Protocol
         BASE_PROTOCOL.initialize();
         BASE_PROTOCOL.register(Via.getManager().getProviders());
-        registerBaseProtocol(new BaseProtocol1_7(), Range.closedOpen(ProtocolVersion.v1_7_2, ProtocolVersion.v1_16));
-        registerBaseProtocol(new BaseProtocol1_16(), Range.atLeast(ProtocolVersion.v1_16));
+        registerBaseProtocol(Direction.CLIENTBOUND, new ClientboundBaseProtocol1_7(), Range.atLeast(ProtocolVersion.v1_7_2));
+        registerBaseProtocol(Direction.SERVERBOUND, new ServerboundBaseProtocol1_7(), Range.atLeast(ProtocolVersion.v1_7_2));
 
         registerProtocol(new Protocol1_8To1_9(), ProtocolVersion.v1_9, ProtocolVersion.v1_8);
         registerProtocol(new Protocol1_9To1_9_1(), Arrays.asList(ProtocolVersion.v1_9_1, ProtocolVersion.v1_9_2), ProtocolVersion.v1_9);
@@ -234,7 +236,7 @@ public class ProtocolManagerImpl implements ProtocolManager {
     }
 
     @Override
-    public void registerBaseProtocol(Protocol baseProtocol, Range<ProtocolVersion> supportedProtocols) {
+    public void registerBaseProtocol(Direction direction, Protocol baseProtocol, Range<ProtocolVersion> supportedProtocols) {
         Preconditions.checkArgument(baseProtocol.isBaseProtocol(), "Protocol is not a base protocol");
         final ProtocolVersion lower = supportedProtocols.hasLowerBound() ? supportedProtocols.lowerEndpoint() : null;
         final ProtocolVersion upper = supportedProtocols.hasUpperBound() ? supportedProtocols.upperEndpoint() : null;
@@ -243,7 +245,11 @@ public class ProtocolManagerImpl implements ProtocolManager {
 
         baseProtocol.initialize();
 
-        baseProtocols.add(new Pair<>(supportedProtocols, baseProtocol));
+        if (direction == Direction.SERVERBOUND) {
+            serverboundBaseProtocols.add(new Pair<>(supportedProtocols, baseProtocol));
+        } else {
+            clientboundBaseProtocols.add(new Pair<>(supportedProtocols, baseProtocol));
+        }
         baseProtocol.register(Via.getManager().getProviders());
         if (Via.getManager().isInitialized()) {
             refreshVersions();
@@ -273,12 +279,14 @@ public class ProtocolManagerImpl implements ProtocolManager {
         ProtocolPathKey protocolKey = new ProtocolPathKeyImpl(clientVersion, serverVersion);
         List<ProtocolPathEntry> protocolList = pathCache.get(protocolKey);
         if (protocolList != null) {
-            return protocolList;
+            return protocolList.isEmpty() ? null : protocolList;
         }
 
         // Calculate path
         Object2ObjectSortedMap<ProtocolVersion, Protocol> outputPath = getProtocolPath(new Object2ObjectLinkedOpenHashMap<>(), clientVersion, serverVersion);
         if (outputPath == null) {
+            // Also cache that there is no path
+            pathCache.put(protocolKey, List.of());
             return null;
         }
 
@@ -365,13 +373,23 @@ public class ProtocolManagerImpl implements ProtocolManager {
     }
 
     @Override
-    public @Nullable Protocol getBaseProtocol(ProtocolVersion serverVersion) {
-        for (Pair<Range<ProtocolVersion>, Protocol> rangeProtocol : Lists.reverse(baseProtocols)) {
-            if (rangeProtocol.key().contains(serverVersion)) {
-                return rangeProtocol.value();
+    public List<Protocol> getBaseProtocols(@Nullable ProtocolVersion clientVersion, @Nullable ProtocolVersion serverVersion) {
+        final List<Protocol> list = new ArrayList<>();
+        if (clientVersion != null) {
+            for (Pair<Range<ProtocolVersion>, Protocol> rangeProtocol : serverboundBaseProtocols) {
+                if (rangeProtocol.key().contains(clientVersion)) {
+                    list.add(rangeProtocol.value());
+                }
             }
         }
-        return null;
+        if (serverVersion != null) {
+            for (Pair<Range<ProtocolVersion>, Protocol> rangeProtocol : clientboundBaseProtocols) {
+                if (rangeProtocol.key().contains(serverVersion)) {
+                    list.add(rangeProtocol.value());
+                }
+            }
+        }
+        return list;
     }
 
     @Override
@@ -518,7 +536,7 @@ public class ProtocolManagerImpl implements ProtocolManager {
         Preconditions.checkArgument(!mappingsLoaded);
 
         // If this log message is missing, something is wrong
-        Via.getPlatform().getLogger().info("Finished mapping loading, shutting down loader executor!");
+        Via.getPlatform().getLogger().info("Finished mapping loading, shutting down loader executor.");
         mappingsLoaded = true;
         mappingLoaderExecutor.shutdown();
         mappingLoaderExecutor = null;

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

@@ -24,8 +24,10 @@ import java.util.Comparator;
 import org.checkerframework.checker.nullness.qual.Nullable;
 
 /**
- * Special protocol version that compares to another version. This can be used for e.g. April Fool versions which are depending
- * on vanilla game versions.
+ * Intended API class for protocol versions with the version type {@link VersionType#SPECIAL}.
+ * <p>
+ * Compares equal to the given origin version and allows base protocol determination via {@link #getBaseProtocolVersion()}
+ * which can be null for special cases where there is no base protocol.
  */
 public class RedirectProtocolVersion extends ProtocolVersion {
 
@@ -52,4 +54,14 @@ public class RedirectProtocolVersion extends ProtocolVersion {
         };
     }
 
+    public ProtocolVersion getOrigin() {
+        return origin;
+    }
+
+    /**
+     * @return the protocol version used to determine the base protocol, null in case there is no base protocol.
+     */
+    public @Nullable ProtocolVersion getBaseProtocolVersion() {
+        return origin;
+    }
 }

common/src/main/java/com/viaversion/viaversion/protocol/packet/PacketWrapperImpl.java

@@ -123,7 +123,7 @@ public class PacketWrapperImpl implements PacketWrapper {
                 continue;
             }
             if (currentIndex == index) {
-                packetValue.setValue(attemptTransform(type, value));
+                packetValue.setValue(value);
                 return;
             }
             currentIndex++;
@@ -133,23 +133,26 @@ public class PacketWrapperImpl implements PacketWrapper {
 
     @Override
     public <T> T read(Type<T> type) {
-        if (readableObjects.isEmpty()) {
-            Preconditions.checkNotNull(inputBuffer, "This packet does not have an input buffer.");
-            // We could in the future log input read values, but honestly for things like bulk maps, mem waste D:
-            try {
-                return type.read(inputBuffer);
-            } catch (Exception e) {
-                throw createInformativeException(e, type, packetValues.size() + 1);
-            }
-        }
+        return readableObjects.isEmpty() ? readFromBuffer(type) : pollReadableObject(type).value;
+    }
 
-        PacketValue readValue = readableObjects.poll();
+    private <T> T readFromBuffer(Type<T> type) {
+        Preconditions.checkNotNull(inputBuffer, "This packet does not have an input buffer.");
+        try {
+            return type.read(inputBuffer);
+        } catch (Exception e) {
+            throw createInformativeException(e, type, packetValues.size() + 1);
+        }
+    }
+
+    private <T> PacketValue<T> pollReadableObject(Type<T> type) {
+        PacketValue<?> readValue = readableObjects.poll();
         Type<?> readType = readValue.type();
         if (readType == type
             || (type.getBaseClass() == readType.getBaseClass()
             && type.getOutputClass() == readType.getOutputClass())) {
             //noinspection unchecked
-            return (T) readValue.value();
+            return (PacketValue<T>) readValue;
         } else {
             throw createInformativeException(new IOException("Unable to read type " + type.getTypeName() + ", found " + readValue.type().getTypeName()), type, readableObjects.size());
         }
@@ -157,7 +160,7 @@ public class PacketWrapperImpl implements PacketWrapper {
 
     @Override
     public <T> void write(Type<T> type, T value) {
-        packetValues.add(new PacketValue<>(type, attemptTransform(type, value)));
+        packetValues.add(new PacketValue<>(type, value));
     }
 
     /**
@@ -167,7 +170,7 @@ public class PacketWrapperImpl implements PacketWrapper {
      * @param value        value
      * @return value if already matching, else the converted value or possibly unmatched value
      */
-    private <T> @Nullable T attemptTransform(Type<T> expectedType, @Nullable T value) {
+    private <T> @Nullable T attemptTransform(Type<T> expectedType, @Nullable Object value) {
         if (value != null && !expectedType.getOutputClass().isAssignableFrom(value.getClass())) {
             // Attempt conversion
             if (expectedType instanceof TypeConverter<?>) {
@@ -177,14 +180,33 @@ public class PacketWrapperImpl implements PacketWrapper {
 
             Via.getPlatform().getLogger().warning("Possible type mismatch: " + value.getClass().getName() + " -> " + expectedType.getOutputClass());
         }
-        return value;
+        //noinspection unchecked
+        return (T) value;
     }
 
     @Override
     public <T> T passthrough(Type<T> type) throws InformativeException {
-        T value = read(type);
-        write(type, value);
-        return value;
+        if (readableObjects.isEmpty()) {
+            T value = readFromBuffer(type);
+            packetValues.add(new PacketValue<>(type, value));
+            return value;
+        } else {
+            PacketValue<T> value = pollReadableObject(type);
+            packetValues.add(value);
+            return value.value;
+        }
+    }
+
+    @Override
+    public <T> T passthroughAndMap(Type<?> type, Type<T> mappedType) throws InformativeException {
+        if (type == mappedType) {
+            return passthrough(mappedType);
+        }
+
+        final Object value = read(type);
+        final T mappedValue = attemptTransform(mappedType, value);
+        write(mappedType, mappedValue);
+        return mappedValue;
     }
 
     @Override
@@ -318,7 +340,7 @@ public class PacketWrapperImpl implements PacketWrapper {
             }
             return user().sendRawPacketFuture(output);
         }
-        return user().getChannel().newFailedFuture(new RuntimeException("Tried to send cancelled packet"));
+        return cancelledFuture();
     }
 
     @Override
@@ -326,6 +348,21 @@ public class PacketWrapperImpl implements PacketWrapper {
         sendRaw(true);
     }
 
+    @Override
+    public ChannelFuture sendFutureRaw() throws InformativeException {
+        if (isCancelled()) {
+            return cancelledFuture();
+        }
+
+        ByteBuf output = inputBuffer == null ? user().getChannel().alloc().buffer() : inputBuffer.alloc().buffer();
+        try {
+            writeToBuffer(output);
+            return user().sendRawPacketFuture(output.retain());
+        } finally {
+            output.release();
+        }
+    }
+
     @Override
     public void scheduleSendRaw() throws InformativeException {
         sendRaw(false);
@@ -349,6 +386,10 @@ public class PacketWrapperImpl implements PacketWrapper {
         }
     }
 
+    private ChannelFuture cancelledFuture() {
+        return user().getChannel().newFailedFuture(new RuntimeException("Tried to send cancelled packet"));
+    }
+
     @Override
     public PacketWrapperImpl create(int packetId) {
         return new PacketWrapperImpl(packetId, null, user());

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

@@ -35,6 +35,7 @@ import com.viaversion.viaversion.api.protocol.version.VersionType;
 import com.viaversion.viaversion.api.type.Types;
 import com.viaversion.viaversion.exception.CancelException;
 import com.viaversion.viaversion.exception.InformativeException;
+import com.viaversion.viaversion.protocol.RedirectProtocolVersion;
 import com.viaversion.viaversion.protocol.version.BaseVersionProvider;
 import com.viaversion.viaversion.protocols.base.packet.BaseClientboundPacket;
 import com.viaversion.viaversion.protocols.base.packet.BasePacketTypesProvider;
@@ -42,34 +43,45 @@ import com.viaversion.viaversion.protocols.base.packet.BaseServerboundPacket;
 import java.util.ArrayList;
 import java.util.List;
 
-public class BaseProtocol extends AbstractProtocol<BaseClientboundPacket, BaseClientboundPacket, BaseServerboundPacket, BaseServerboundPacket> {
+/**
+ * Initial base protocol which is kept always in the pipeline.
+ * <p>
+ * State tracking for configuration state is done via {@link AbstractProtocol#registerConfigurationChangeHandlers()}
+ */
+public class InitialBaseProtocol extends AbstractProtocol<BaseClientboundPacket, BaseClientboundPacket, BaseServerboundPacket, BaseServerboundPacket> {
 
     private static final int STATUS_INTENT = 1;
     private static final int LOGIN_INTENT = 2;
     private static final int TRANSFER_INTENT = 3;
 
-    public BaseProtocol() {
+    public InitialBaseProtocol() {
         super(BaseClientboundPacket.class, BaseClientboundPacket.class, BaseServerboundPacket.class, BaseServerboundPacket.class);
     }
 
     @Override
     protected void registerPackets() {
-        // Handshake Packet
+        // Setup protocol pipeline + track initial state
         registerServerbound(ServerboundHandshakePackets.CLIENT_INTENTION, wrapper -> {
             int protocolVersion = wrapper.passthrough(Types.VAR_INT);
             wrapper.passthrough(Types.STRING); // Server Address
             wrapper.passthrough(Types.UNSIGNED_SHORT); // Server Port
             int state = wrapper.passthrough(Types.VAR_INT);
 
-            ProtocolInfo info = wrapper.user().getProtocolInfo();
-            info.setProtocolVersion(ProtocolVersion.getProtocol(protocolVersion));
-            // Ensure the server has a version provider
             VersionProvider versionProvider = Via.getManager().getProviders().get(VersionProvider.class);
+            // Ensure the server has a version provider
             if (versionProvider == null) {
                 wrapper.user().setActive(false);
                 return;
             }
 
+            ProtocolInfo info = wrapper.user().getProtocolInfo();
+            info.setProtocolVersion(ProtocolVersion.getProtocol(protocolVersion));
+
+            ProtocolVersion clientVersion = versionProvider.getClientProtocol(wrapper.user());
+            if (clientVersion != null) {
+                info.setProtocolVersion(clientVersion);
+            }
+
             // Choose the pipe
             ProtocolVersion serverProtocol;
             try {
@@ -83,16 +95,22 @@ public class BaseProtocol extends AbstractProtocol<BaseClientboundPacket, BaseCl
             ProtocolManager protocolManager = Via.getManager().getProtocolManager();
             List<ProtocolPathEntry> protocolPath = protocolManager.getProtocolPath(info.protocolVersion(), serverProtocol);
 
-            // Add Base Protocol
             ProtocolPipeline pipeline = info.getPipeline();
 
-            // Special versions might compare equal to normal versions and would break this getter
+            // Save manually added protocols for later
+            List<Protocol> alreadyAdded = new ArrayList<>(pipeline.pipes());
+
+            // Special versions might compare equal to normal versions and would the normal lookup,
+            // platforms can use the RedirectProtocolVersion API or need to manually handle their base protocols.
+            ProtocolVersion clientboundBaseProtocolVersion = null;
             if (serverProtocol.getVersionType() != VersionType.SPECIAL) {
-                final Protocol baseProtocol = protocolManager.getBaseProtocol(serverProtocol);
-                // Platforms might add their base protocol manually (e.g. SPECIAL versions)
-                if (baseProtocol != null) {
-                    pipeline.add(baseProtocol);
-                }
+                clientboundBaseProtocolVersion = serverProtocol;
+            } else if (serverProtocol instanceof RedirectProtocolVersion version) {
+                clientboundBaseProtocolVersion = version.getBaseProtocolVersion();
+            }
+            // Add base protocols
+            for (final Protocol protocol : protocolManager.getBaseProtocols(info.protocolVersion(), clientboundBaseProtocolVersion)) {
+                pipeline.add(protocol);
             }
 
             // Add other protocols
@@ -112,11 +130,22 @@ public class BaseProtocol extends AbstractProtocol<BaseClientboundPacket, BaseCl
                 wrapper.set(Types.VAR_INT, 0, serverProtocol.getOriginalVersion());
             }
 
+            // Send client intention into the pipeline in case protocols down the line need to transform it
+            try {
+                final List<Protocol> protocols = new ArrayList<>(pipeline.pipes());
+                protocols.removeAll(alreadyAdded); // Skip all manually added protocols to prevent double handling
+                wrapper.resetReader();
+                wrapper.apply(Direction.SERVERBOUND, State.HANDSHAKE, protocols);
+            } catch (CancelException e) {
+                wrapper.cancel();
+            }
+
             if (Via.getManager().isDebug()) {
                 Via.getPlatform().getLogger().info("User connected with protocol: " + info.protocolVersion() + " and serverProtocol: " + info.serverProtocolVersion());
                 Via.getPlatform().getLogger().info("Protocol pipeline: " + pipeline.pipes());
             }
 
+            // Set initial state
             if (state == STATUS_INTENT) {
                 info.setState(State.STATUS);
             } else if (state == LOGIN_INTENT) {
@@ -156,4 +185,4 @@ public class BaseProtocol extends AbstractProtocol<BaseClientboundPacket, BaseCl
     protected PacketTypesProvider<BaseClientboundPacket, BaseClientboundPacket, BaseServerboundPacket, BaseServerboundPacket> createPacketTypesProvider() {
         return BasePacketTypesProvider.INSTANCE;
     }
-}
+}

common/src/main/java/com/viaversion/viaversion/protocols/base/v1_7/ClientboundBaseProtocol1_7.java

@@ -15,7 +15,7 @@
  * 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.base;
+package com.viaversion.viaversion.protocols.base.v1_7;
 
 import com.google.common.base.Joiner;
 import com.google.gson.JsonElement;
@@ -26,7 +26,6 @@ import com.viaversion.viaversion.api.connection.ProtocolInfo;
 import com.viaversion.viaversion.api.connection.UserConnection;
 import com.viaversion.viaversion.api.protocol.AbstractProtocol;
 import com.viaversion.viaversion.api.protocol.ProtocolPathEntry;
-import com.viaversion.viaversion.api.protocol.packet.PacketWrapper;
 import com.viaversion.viaversion.api.protocol.packet.State;
 import com.viaversion.viaversion.api.protocol.packet.provider.PacketTypesProvider;
 import com.viaversion.viaversion.api.protocol.remapper.PacketHandlers;
@@ -35,25 +34,25 @@ import com.viaversion.viaversion.api.protocol.version.VersionProvider;
 import com.viaversion.viaversion.api.type.Types;
 import com.viaversion.viaversion.protocol.ProtocolManagerImpl;
 import com.viaversion.viaversion.protocol.ServerProtocolVersionSingleton;
+import com.viaversion.viaversion.protocols.base.ClientboundLoginPackets;
+import com.viaversion.viaversion.protocols.base.ClientboundStatusPackets;
 import com.viaversion.viaversion.protocols.base.packet.BaseClientboundPacket;
 import com.viaversion.viaversion.protocols.base.packet.BasePacketTypesProvider;
 import com.viaversion.viaversion.protocols.base.packet.BaseServerboundPacket;
-import com.viaversion.viaversion.util.ChatColorUtil;
-import com.viaversion.viaversion.util.ComponentUtil;
 import com.viaversion.viaversion.util.GsonUtil;
-import io.netty.channel.ChannelFuture;
 import java.util.List;
 import java.util.UUID;
 import java.util.logging.Level;
 
-public class BaseProtocol1_7 extends AbstractProtocol<BaseClientboundPacket, BaseClientboundPacket, BaseServerboundPacket, BaseServerboundPacket> {
+public class ClientboundBaseProtocol1_7 extends AbstractProtocol<BaseClientboundPacket, BaseClientboundPacket, BaseServerboundPacket, BaseServerboundPacket> {
 
-    public BaseProtocol1_7() {
+    public ClientboundBaseProtocol1_7() {
         super(BaseClientboundPacket.class, BaseClientboundPacket.class, BaseServerboundPacket.class, BaseServerboundPacket.class);
     }
 
     @Override
     protected void registerPackets() {
+        // Handle server pinging sent by the client
         registerClientbound(ClientboundStatusPackets.STATUS_RESPONSE, new PacketHandlers() {
             @Override
             public void register() {
@@ -128,60 +127,27 @@ public class BaseProtocol1_7 extends AbstractProtocol<BaseClientboundPacket, Bas
             }
         });
 
-        // Login Success Packet
+        // Track player name/uuid and setup connection + track state
         registerClientbound(ClientboundLoginPackets.GAME_PROFILE, wrapper -> {
-            ProtocolInfo info = wrapper.user().getProtocolInfo();
-            if (info.protocolVersion().olderThan(ProtocolVersion.v1_20_2)) { // On 1.20.2+, wait for the login ack
-                info.setState(State.PLAY);
-            }
-
-            UUID uuid = passthroughLoginUUID(wrapper);
-            info.setUuid(uuid);
-
-            String username = wrapper.passthrough(Types.STRING);
-            info.setUsername(username);
-            // Add to ported clients
-            Via.getManager().getConnectionManager().onLoginSuccess(wrapper.user());
-
-            if (!info.getPipeline().hasNonBaseProtocols()) { // Only base protocol
-                wrapper.user().setActive(false);
-            }
-
-            if (Via.getManager().isDebug()) {
-                // Print out the route to console
-                Via.getPlatform().getLogger().log(Level.INFO, "{0} logged in with protocol {1}, Route: {2}",
-                    new Object[]{
-                        username,
-                        info.protocolVersion().getName(),
-                        Joiner.on(", ").join(info.getPipeline().pipes(), ", ")
-                    });
-            }
-        });
-
-        // Login Start Packet
-        registerServerbound(ServerboundLoginPackets.HELLO, wrapper -> {
-            final UserConnection user = wrapper.user();
-            final ProtocolVersion protocol = user.getProtocolInfo().protocolVersion();
-            if (Via.getConfig().blockedProtocolVersions().contains(protocol)) {
-                if (!user.getChannel().isOpen() || !user.shouldApplyBlockProtocol()) {
-                    return;
-                }
-
-                wrapper.cancel(); // cancel current
-
-                final String disconnectMessage = ChatColorUtil.translateAlternateColorCodes(Via.getConfig().getBlockedDisconnectMsg());
-                final PacketWrapper disconnectPacket = PacketWrapper.create(ClientboundLoginPackets.LOGIN_DISCONNECT, user);
-                disconnectPacket.write(Types.COMPONENT, ComponentUtil.plainToJson(disconnectMessage));
-
-                // Send and close
-                final ChannelFuture future = disconnectPacket.sendFuture(null);
-                future.addListener(f -> user.getChannel().close());
-            }
-        });
-
-        registerServerbound(ServerboundLoginPackets.LOGIN_ACKNOWLEDGED, wrapper -> {
             final ProtocolInfo info = wrapper.user().getProtocolInfo();
-            info.setState(State.CONFIGURATION);
+
+            if (info.serverProtocolVersion().olderThan(ProtocolVersion.v1_16)) {
+                String uuidString = wrapper.passthrough(Types.STRING);
+                if (uuidString.length() == 32) { // Trimmed UUIDs are 32 characters
+                    // Trimmed
+                    uuidString = addDashes(uuidString);
+                }
+                info.setUuid(UUID.fromString(uuidString));
+            } else {
+                final UUID uuid = wrapper.passthrough(Types.UUID);
+                info.setUuid(uuid);
+            }
+
+            final String username = wrapper.passthrough(Types.STRING);
+            info.setUsername(username);
+
+            // Setup connection
+            onLoginSuccess(wrapper.user());
         });
     }
 
@@ -199,13 +165,28 @@ public class BaseProtocol1_7 extends AbstractProtocol<BaseClientboundPacket, Bas
         return idBuff.toString();
     }
 
-    protected UUID passthroughLoginUUID(PacketWrapper wrapper) {
-        String uuidString = wrapper.passthrough(Types.STRING);
-        if (uuidString.length() == 32) { // Trimmed UUIDs are 32 characters
-            // Trimmed
-            uuidString = addDashes(uuidString);
+    public static void onLoginSuccess(final UserConnection connection) {
+        final ProtocolInfo info = connection.getProtocolInfo();
+        if (info.protocolVersion().olderThan(ProtocolVersion.v1_20_2)) { // On 1.20.2+, wait for the login ack
+            info.setState(State.PLAY);
+        }
+
+        // Add to ported clients
+        Via.getManager().getConnectionManager().onLoginSuccess(connection);
+
+        if (!info.getPipeline().hasNonBaseProtocols()) { // Only base protocol
+            connection.setActive(false);
+        }
+
+        if (Via.getManager().isDebug()) {
+            // Print out the route to console
+            Via.getPlatform().getLogger().log(Level.INFO, "{0} logged in with protocol {1}, Route: {2}",
+                new Object[]{
+                    info.getUsername(),
+                    info.protocolVersion().getName(),
+                    Joiner.on(", ").join(info.getPipeline().pipes(), ", ")
+                });
         }
-        return UUID.fromString(uuidString);
     }
 
     @Override

common/src/main/java/com/viaversion/viaversion/protocols/base/v1_7/ServerboundBaseProtocol1_7.java

@@ -0,0 +1,91 @@
+/*
+ * This file is part of ViaVersion - https://github.com/ViaVersion/ViaVersion
+ * Copyright (C) 2016-2024 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.base.v1_7;
+
+import com.google.gson.JsonObject;
+import com.viaversion.viaversion.api.Via;
+import com.viaversion.viaversion.api.connection.ProtocolInfo;
+import com.viaversion.viaversion.api.connection.UserConnection;
+import com.viaversion.viaversion.api.protocol.AbstractProtocol;
+import com.viaversion.viaversion.api.protocol.packet.PacketWrapper;
+import com.viaversion.viaversion.api.protocol.packet.State;
+import com.viaversion.viaversion.api.protocol.packet.provider.PacketTypesProvider;
+import com.viaversion.viaversion.api.protocol.version.ProtocolVersion;
+import com.viaversion.viaversion.api.type.Types;
+import com.viaversion.viaversion.protocols.base.ClientboundLoginPackets;
+import com.viaversion.viaversion.protocols.base.ServerboundLoginPackets;
+import com.viaversion.viaversion.protocols.base.packet.BaseClientboundPacket;
+import com.viaversion.viaversion.protocols.base.packet.BasePacketTypesProvider;
+import com.viaversion.viaversion.protocols.base.packet.BaseServerboundPacket;
+import com.viaversion.viaversion.protocols.v1_8to1_9.Protocol1_8To1_9;
+import com.viaversion.viaversion.util.ChatColorUtil;
+import com.viaversion.viaversion.util.ComponentUtil;
+import io.netty.channel.ChannelFuture;
+
+public class ServerboundBaseProtocol1_7 extends AbstractProtocol<BaseClientboundPacket, BaseClientboundPacket, BaseServerboundPacket, BaseServerboundPacket> {
+
+    public ServerboundBaseProtocol1_7() {
+        super(BaseClientboundPacket.class, BaseClientboundPacket.class, BaseServerboundPacket.class, BaseServerboundPacket.class);
+    }
+
+    @Override
+    protected void registerPackets() {
+        // State tracking
+        registerServerbound(ServerboundLoginPackets.LOGIN_ACKNOWLEDGED, wrapper -> {
+            final ProtocolInfo info = wrapper.user().getProtocolInfo();
+            info.setState(State.CONFIGURATION);
+        });
+
+        // Handle blocked version disconnect
+        registerServerbound(ServerboundLoginPackets.HELLO, wrapper -> {
+            final UserConnection user = wrapper.user();
+            final ProtocolVersion protocol = user.getProtocolInfo().protocolVersion();
+            if (Via.getConfig().blockedProtocolVersions().contains(protocol)) {
+                if (!user.getChannel().isOpen() || !user.shouldApplyBlockProtocol()) {
+                    return;
+                }
+
+                wrapper.cancel(); // cancel current
+
+                final String disconnectMessage = ChatColorUtil.translateAlternateColorCodes(Via.getConfig().getBlockedDisconnectMsg());
+                final PacketWrapper disconnectPacket = PacketWrapper.create(ClientboundLoginPackets.LOGIN_DISCONNECT, user);
+
+                final JsonObject object = ComponentUtil.plainToJson(disconnectMessage);
+                if (protocol.olderThanOrEqualTo(ProtocolVersion.v1_8)) {
+                    disconnectPacket.write(Types.STRING, object.toString());
+                } else {
+                    disconnectPacket.write(Types.COMPONENT, object);
+                }
+
+                // Send and close
+                final ChannelFuture future = disconnectPacket.sendFutureRaw();
+                future.addListener(f -> user.getChannel().close());
+            }
+        });
+    }
+
+    @Override
+    public boolean isBaseProtocol() {
+        return true;
+    }
+
+    @Override
+    protected PacketTypesProvider<BaseClientboundPacket, BaseClientboundPacket, BaseServerboundPacket, BaseServerboundPacket> createPacketTypesProvider() {
+        return BasePacketTypesProvider.INSTANCE;
+    }
+}

common/src/main/java/com/viaversion/viaversion/protocols/template/BlockItemPacketRewriter1_99.java

@@ -15,26 +15,31 @@
  * 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.template.protocols.rewriter;
+package com.viaversion.viaversion.protocols.template;
 
 import com.viaversion.viaversion.api.type.types.chunk.ChunkType1_20_2;
-import com.viaversion.viaversion.api.type.types.version.Types1_20_5;
+import com.viaversion.viaversion.api.type.types.version.Types1_21;
 import com.viaversion.viaversion.protocols.v1_20_2to1_20_3.rewriter.RecipeRewriter1_20_3;
-import com.viaversion.viaversion.protocols.v1_20_3to1_20_5.packet.ClientboundPacket1_20_5;
-import com.viaversion.viaversion.protocols.v1_20_3to1_20_5.packet.ClientboundPackets1_20_5;
 import com.viaversion.viaversion.protocols.v1_20_3to1_20_5.packet.ServerboundPacket1_20_5;
 import com.viaversion.viaversion.protocols.v1_20_3to1_20_5.packet.ServerboundPackets1_20_5;
+import com.viaversion.viaversion.protocols.v1_20_5to1_21.packet.ClientboundPacket1_21;
+import com.viaversion.viaversion.protocols.v1_20_5to1_21.packet.ClientboundPackets1_21;
 import com.viaversion.viaversion.rewriter.BlockRewriter;
 import com.viaversion.viaversion.rewriter.StructuredItemRewriter;
-import com.viaversion.viaversion.template.protocols.Protocol1_99To_98;
 
 // To replace if needed:
 //   ChunkType1_20_2
 //   RecipeRewriter1_20_3
-public final class BlockItemPacketRewriter1_99 extends StructuredItemRewriter<ClientboundPacket1_20_5, ServerboundPacket1_20_5, Protocol1_99To_98> {
+//   Types1_21, Types1_OLD
+final class BlockItemPacketRewriter1_99 extends StructuredItemRewriter<ClientboundPacket1_21, ServerboundPacket1_20_5, Protocol1_99To_98> {
 
     public BlockItemPacketRewriter1_99(final Protocol1_99To_98 protocol) {
-        super(protocol, /*TypesOLD.ITEM, TypesOLD.ITEM_ARRAY, */Types1_20_5.ITEM, Types1_20_5.ITEM_ARRAY);
+        super(protocol, Types1_21.ITEM, Types1_21.ITEM_ARRAY);
+        /*super(protocol,
+            Types1_OLD.ITEM, Types1_OLD.ITEM_ARRAY, Types1_21.ITEM, Types1_21.ITEM_ARRAY,
+            Types1_OLD.ITEM_COST, Types1_OLD.OPTIONAL_ITEM_COST, Types1_21.ITEM_COST, Types1_21.OPTIONAL_ITEM_COST,
+            Types1_OLD.PARTICLE, Types1_21.PARTICLE
+        );*/
     }
 
     @Override
@@ -42,32 +47,31 @@ public final class BlockItemPacketRewriter1_99 extends StructuredItemRewriter<Cl
         // Register block and block state id changes
         // Other places using block state id mappings: Spawn particle, entity data, entity spawn (falling blocks)
         // Tags and statistics use block (!) ids
-        final BlockRewriter<ClientboundPacket1_20_5> blockRewriter = BlockRewriter.for1_20_2(protocol);
-        blockRewriter.registerBlockEvent(ClientboundPackets1_20_5.BLOCK_EVENT);
-        blockRewriter.registerBlockUpdate(ClientboundPackets1_20_5.BLOCK_UPDATE);
-        blockRewriter.registerSectionBlocksUpdate1_20(ClientboundPackets1_20_5.SECTION_BLOCKS_UPDATE);
-        blockRewriter.registerLevelEvent1_21(ClientboundPackets1_20_5.LEVEL_EVENT, 2001);
-        blockRewriter.registerLevelChunk1_19(ClientboundPackets1_20_5.LEVEL_CHUNK_WITH_LIGHT, ChunkType1_20_2::new);
-        blockRewriter.registerBlockEntityData(ClientboundPackets1_20_5.BLOCK_ENTITY_DATA);
+        final BlockRewriter<ClientboundPacket1_21> blockRewriter = BlockRewriter.for1_20_2(protocol);
+        blockRewriter.registerBlockEvent(ClientboundPackets1_21.BLOCK_EVENT);
+        blockRewriter.registerBlockUpdate(ClientboundPackets1_21.BLOCK_UPDATE);
+        blockRewriter.registerSectionBlocksUpdate1_20(ClientboundPackets1_21.SECTION_BLOCKS_UPDATE);
+        blockRewriter.registerLevelEvent1_21(ClientboundPackets1_21.LEVEL_EVENT, 2001);
+        blockRewriter.registerLevelChunk1_19(ClientboundPackets1_21.LEVEL_CHUNK_WITH_LIGHT, ChunkType1_20_2::new);
+        blockRewriter.registerBlockEntityData(ClientboundPackets1_21.BLOCK_ENTITY_DATA);
 
         // Registers item id changes
         // Other places using item ids are: Entity data, tags, statistics, effect
-        // registerOpenWindow(ClientboundPackets1_20_5.OPEN_WINDOW); - If a new container type was added
-        registerCooldown(ClientboundPackets1_20_5.COOLDOWN);
-        registerSetContent1_17_1(ClientboundPackets1_20_5.CONTAINER_SET_CONTENT);
-        registerSetSlot1_17_1(ClientboundPackets1_20_5.CONTAINER_SET_SLOT);
-        registerAdvancements1_20_3(ClientboundPackets1_20_5.UPDATE_ADVANCEMENTS);
-        registerSetEquipment(ClientboundPackets1_20_5.SET_EQUIPMENT);
+        // registerOpenWindow(ClientboundPackets1_21.OPEN_WINDOW); - If a new container type was added
+        registerCooldown(ClientboundPackets1_21.COOLDOWN);
+        registerSetContent1_17_1(ClientboundPackets1_21.CONTAINER_SET_CONTENT);
+        registerSetSlot1_17_1(ClientboundPackets1_21.CONTAINER_SET_SLOT);
+        registerAdvancements1_20_3(ClientboundPackets1_21.UPDATE_ADVANCEMENTS);
+        registerSetEquipment(ClientboundPackets1_21.SET_EQUIPMENT);
         registerContainerClick1_17_1(ServerboundPackets1_20_5.CONTAINER_CLICK);
-        registerMerchantOffers1_20_5(ClientboundPackets1_20_5.MERCHANT_OFFERS, Types1_20_5.ITEM_COST, Types1_20_5.ITEM_COST, Types1_20_5.OPTIONAL_ITEM_COST, Types1_20_5.OPTIONAL_ITEM_COST);
+        registerMerchantOffers1_20_5(ClientboundPackets1_21.MERCHANT_OFFERS);
         registerSetCreativeModeSlot(ServerboundPackets1_20_5.SET_CREATIVE_MODE_SLOT);
-        registerContainerSetData(ClientboundPackets1_20_5.CONTAINER_SET_DATA);
-        registerLevelParticles1_20_5(ClientboundPackets1_20_5.LEVEL_PARTICLES, Types1_20_5.PARTICLE, Types1_20_5.PARTICLE);
-        registerExplosion(ClientboundPackets1_20_5.EXPLODE, Types1_20_5.PARTICLE, Types1_20_5.PARTICLE); // Rewrites the included sound and particles
+        registerLevelParticles1_20_5(ClientboundPackets1_21.LEVEL_PARTICLES);
+        registerExplosion(ClientboundPackets1_21.EXPLODE); // Rewrites the included sound and particles
 
-        new RecipeRewriter1_20_3<>(protocol).register1_20_5(ClientboundPackets1_20_5.UPDATE_RECIPES);
+        new RecipeRewriter1_20_3<>(protocol).register1_20_5(ClientboundPackets1_21.UPDATE_RECIPES);
         // OR do this if serialization of recipes changed and override the relevant method
         // Add new serializers to RecipeRewriter, or extend the last one for changes
-        // new RecipeRewriter1_20_3<ClientboundPackets1_20_5>(this) {}.register1_20_5(ClientboundPackets1_20_5.DECLARE_RECIPES);
+        // new RecipeRewriter1_20_3<ClientboundPacket1_21>(this) {}.register1_20_5(ClientboundPackets1_21.DECLARE_RECIPES);
     }
-}
+}

common/src/main/java/com/viaversion/viaversion/protocols/template/EntityPacketRewriter1_99.java

@@ -15,25 +15,24 @@
  * 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.template.protocols.rewriter;
+package com.viaversion.viaversion.protocols.template;
 
 import com.viaversion.viaversion.api.minecraft.RegistryEntry;
 import com.viaversion.viaversion.api.minecraft.entities.EntityType;
 import com.viaversion.viaversion.api.minecraft.entities.EntityTypes1_20_5;
 import com.viaversion.viaversion.api.protocol.remapper.PacketHandlers;
 import com.viaversion.viaversion.api.type.Types;
-import com.viaversion.viaversion.api.type.types.version.Types1_20_5;
-import com.viaversion.viaversion.protocols.v1_20_3to1_20_5.packet.ClientboundConfigurationPackets1_20_5;
-import com.viaversion.viaversion.protocols.v1_20_3to1_20_5.packet.ClientboundPacket1_20_5;
-import com.viaversion.viaversion.protocols.v1_20_3to1_20_5.packet.ClientboundPackets1_20_5;
+import com.viaversion.viaversion.api.type.types.version.Types1_21;
+import com.viaversion.viaversion.protocols.v1_20_5to1_21.packet.ClientboundConfigurationPackets1_21;
+import com.viaversion.viaversion.protocols.v1_20_5to1_21.packet.ClientboundPacket1_21;
+import com.viaversion.viaversion.protocols.v1_20_5to1_21.packet.ClientboundPackets1_21;
 import com.viaversion.viaversion.rewriter.EntityRewriter;
-import com.viaversion.viaversion.template.protocols.Protocol1_99To_98;
 import com.viaversion.viaversion.util.Key;
 
 // Replace if needed
 //  Types1_OLD
-//  Types1_20_5
-public final class EntityPacketRewriter1_99 extends EntityRewriter<ClientboundPacket1_20_5, Protocol1_99To_98> {
+//  Types1_21
+final class EntityPacketRewriter1_99 extends EntityRewriter<ClientboundPacket1_21, Protocol1_99To_98> {
 
     public EntityPacketRewriter1_99(final Protocol1_99To_98 protocol) {
         super(protocol);
@@ -42,17 +41,17 @@ public final class EntityPacketRewriter1_99 extends EntityRewriter<ClientboundPa
     @Override
     public void registerPackets() {
         // Tracks entities, applies entity data rewrites registered below, untracks entities
-        registerTrackerWithData1_19(ClientboundPackets1_20_5.ADD_ENTITY, EntityTypes1_20_5.FALLING_BLOCK);
-        registerSetEntityData(ClientboundPackets1_20_5.SET_ENTITY_DATA, /*Types1_OLD_ENTITY_DATA_LIST, */Types1_20_5.ENTITY_DATA_LIST); // Specify old and new entity data list if changed
-        registerRemoveEntities(ClientboundPackets1_20_5.REMOVE_ENTITIES);
+        registerTrackerWithData1_19(ClientboundPackets1_21.ADD_ENTITY, EntityTypes1_20_5.FALLING_BLOCK);
+        registerSetEntityData(ClientboundPackets1_21.SET_ENTITY_DATA, /*Types1_OLD_ENTITY_DATA_LIST, */Types1_21.ENTITY_DATA_LIST); // Specify old and new entity data list if changed
+        registerRemoveEntities(ClientboundPackets1_21.REMOVE_ENTITIES);
 
-        protocol.registerClientbound(ClientboundConfigurationPackets1_20_5.REGISTRY_DATA, wrapper -> {
+        protocol.registerClientbound(ClientboundConfigurationPackets1_21.REGISTRY_DATA, wrapper -> {
             final String registryKey = Key.stripMinecraftNamespace(wrapper.passthrough(Types.STRING));
             final RegistryEntry[] entries = wrapper.passthrough(Types.REGISTRY_ENTRY_ARRAY);
             handleRegistryData1_20_5(wrapper.user(), registryKey, entries); // Caches dimensions to access data like height later and tracks the amount of biomes sent for chunk data
         });
 
-        protocol.registerClientbound(ClientboundPackets1_20_5.LOGIN, new PacketHandlers() {
+        protocol.registerClientbound(ClientboundPackets1_21.LOGIN, new PacketHandlers() {
             @Override
             public void register() {
                 map(Types.INT); // Entity id
@@ -71,7 +70,7 @@ public final class EntityPacketRewriter1_99 extends EntityRewriter<ClientboundPa
             }
         });
 
-        protocol.registerClientbound(ClientboundPackets1_20_5.RESPAWN, wrapper -> {
+        protocol.registerClientbound(ClientboundPackets1_21.RESPAWN, wrapper -> {
             final int dimensionId = wrapper.passthrough(Types.VAR_INT);
             final String world = wrapper.passthrough(Types.STRING);
             trackWorldDataByKey1_20_5(wrapper.user(), dimensionId, world); // Tracks world height and name for chunk data and entity (un)tracking
@@ -82,24 +81,23 @@ public final class EntityPacketRewriter1_99 extends EntityRewriter<ClientboundPa
     protected void registerRewrites() {
         /* Uncomment if entity data classes changed
         filter().mapDataType(typeId -> {
-            final int id = typeId;
+            int id = typeId;
             if (id >= SomeAddedIndex) {
                 id++;
             }
-            return Types1_20_5.ENTITY_DATA_TYPES.byId(id);
+            return Types1_21.ENTITY_DATA_TYPES.byId(id);
         });*/
 
         // Registers registry type id changes
         registerEntityDataTypeHandler(
-            Types1_20_5.ENTITY_DATA_TYPES.itemType,
-            Types1_20_5.ENTITY_DATA_TYPES.blockStateType,
-            Types1_20_5.ENTITY_DATA_TYPES.optionalBlockStateType,
-            Types1_20_5.ENTITY_DATA_TYPES.particleType,
-            Types1_20_5.ENTITY_DATA_TYPES.particlesType,
-            Types1_20_5.ENTITY_DATA_TYPES.componentType,
-            Types1_20_5.ENTITY_DATA_TYPES.optionalComponentType
+            Types1_21.ENTITY_DATA_TYPES.itemType,
+            Types1_21.ENTITY_DATA_TYPES.blockStateType,
+            Types1_21.ENTITY_DATA_TYPES.optionalBlockStateType,
+            Types1_21.ENTITY_DATA_TYPES.particleType,
+            Types1_21.ENTITY_DATA_TYPES.particlesType,
+            Types1_21.ENTITY_DATA_TYPES.componentType,
+            Types1_21.ENTITY_DATA_TYPES.optionalComponentType
         );
-        // Minecarts are special
         registerBlockStateHandler(EntityTypes1_20_5.ABSTRACT_MINECART, 11);
     }
 
@@ -113,4 +111,4 @@ public final class EntityPacketRewriter1_99 extends EntityRewriter<ClientboundPa
     public EntityType typeFromId(final int type) {
         return EntityTypes1_20_5.getTypeFromId(type);
     }
-}
+}

common/src/main/java/com/viaversion/viaversion/protocols/template/Protocol1_99To_98.java

@@ -15,7 +15,7 @@
  * 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.template.protocols;
+package com.viaversion.viaversion.protocols.template;
 
 import com.viaversion.viaversion.api.connection.UserConnection;
 import com.viaversion.viaversion.api.data.MappingData;
@@ -25,68 +25,63 @@ import com.viaversion.viaversion.api.protocol.AbstractProtocol;
 import com.viaversion.viaversion.api.protocol.packet.provider.PacketTypesProvider;
 import com.viaversion.viaversion.api.protocol.packet.provider.SimplePacketTypesProvider;
 import com.viaversion.viaversion.data.entity.EntityTrackerBase;
-import com.viaversion.viaversion.protocols.v1_20_3to1_20_5.packet.ClientboundConfigurationPackets1_20_5;
-import com.viaversion.viaversion.protocols.v1_20_3to1_20_5.packet.ClientboundPacket1_20_5;
-import com.viaversion.viaversion.protocols.v1_20_3to1_20_5.packet.ClientboundPackets1_20_5;
 import com.viaversion.viaversion.protocols.v1_20_3to1_20_5.packet.ServerboundConfigurationPackets1_20_5;
 import com.viaversion.viaversion.protocols.v1_20_3to1_20_5.packet.ServerboundPacket1_20_5;
 import com.viaversion.viaversion.protocols.v1_20_3to1_20_5.packet.ServerboundPackets1_20_5;
+import com.viaversion.viaversion.protocols.v1_20_5to1_21.packet.ClientboundConfigurationPackets1_21;
+import com.viaversion.viaversion.protocols.v1_20_5to1_21.packet.ClientboundPacket1_21;
+import com.viaversion.viaversion.protocols.v1_20_5to1_21.packet.ClientboundPackets1_21;
 import com.viaversion.viaversion.rewriter.AttributeRewriter;
 import com.viaversion.viaversion.rewriter.SoundRewriter;
 import com.viaversion.viaversion.rewriter.StatisticsRewriter;
 import com.viaversion.viaversion.rewriter.TagRewriter;
-import com.viaversion.viaversion.template.protocols.rewriter.BlockItemPacketRewriter1_99;
-import com.viaversion.viaversion.template.protocols.rewriter.EntityPacketRewriter1_99;
 
 import static com.viaversion.viaversion.util.ProtocolUtil.packetTypeMap;
 
 // Placeholders to replace (in the entire package):
-//   Protocol1_99To_98, EntityPacketRewriter1_99, BlockItemPacketRewriter1_99
-//   ClientboundPacket1_20_5
+//   Protocol1_99To_98, EntityPacketRewriter1_99, BlockItemPacketRewriter1_99 - move the latter two to a rewriter package
+//   ClientboundPacket1_21
 //   ServerboundPacket1_20_5
 //   EntityTypes1_20_5 (MAPPED type)
 //   1.99, 1.98
-public final class Protocol1_99To_98 extends AbstractProtocol<ClientboundPacket1_20_5, ClientboundPacket1_20_5, ServerboundPacket1_20_5, ServerboundPacket1_20_5> {
+final class Protocol1_99To_98 extends AbstractProtocol<ClientboundPacket1_21, ClientboundPacket1_21, ServerboundPacket1_20_5, ServerboundPacket1_20_5> {
 
     public static final MappingData MAPPINGS = new MappingDataBase("1.98", "1.99");
     private final EntityPacketRewriter1_99 entityRewriter = new EntityPacketRewriter1_99(this);
     private final BlockItemPacketRewriter1_99 itemRewriter = new BlockItemPacketRewriter1_99(this);
-    private final TagRewriter<ClientboundPacket1_20_5> tagRewriter = new TagRewriter<>(this);
+    private final TagRewriter<ClientboundPacket1_21> tagRewriter = new TagRewriter<>(this);
 
     public Protocol1_99To_98() {
         // Passing the class types into the super constructor is needed for automatic packet type id remapping, but can otherwise be omitted
-        super(ClientboundPacket1_20_5.class, ClientboundPacket1_20_5.class, ServerboundPacket1_20_5.class, ServerboundPacket1_20_5.class);
+        super(ClientboundPacket1_21.class, ClientboundPacket1_21.class, ServerboundPacket1_20_5.class, ServerboundPacket1_20_5.class);
     }
 
     @Override
     protected void registerPackets() {
         super.registerPackets();
 
-        tagRewriter.registerGeneric(ClientboundPackets1_20_5.UPDATE_TAGS);
-        tagRewriter.registerGeneric(ClientboundConfigurationPackets1_20_5.UPDATE_TAGS);
+        tagRewriter.registerGeneric(ClientboundPackets1_21.UPDATE_TAGS);
+        tagRewriter.registerGeneric(ClientboundConfigurationPackets1_21.UPDATE_TAGS);
 
-        final SoundRewriter<ClientboundPacket1_20_5> soundRewriter = new SoundRewriter<>(this);
-        soundRewriter.registerSound1_19_3(ClientboundPackets1_20_5.SOUND);
-        soundRewriter.registerSound1_19_3(ClientboundPackets1_20_5.SOUND_ENTITY);
+        final SoundRewriter<ClientboundPacket1_21> soundRewriter = new SoundRewriter<>(this);
+        soundRewriter.registerSound1_19_3(ClientboundPackets1_21.SOUND);
+        soundRewriter.registerSound1_19_3(ClientboundPackets1_21.SOUND_ENTITY);
 
-        new StatisticsRewriter<>(this).register(ClientboundPackets1_20_5.AWARD_STATS);
-        new AttributeRewriter<>(this).register1_21(ClientboundPackets1_20_5.UPDATE_ATTRIBUTES);
+        new StatisticsRewriter<>(this).register(ClientboundPackets1_21.AWARD_STATS);
+        new AttributeRewriter<>(this).register1_21(ClientboundPackets1_21.UPDATE_ATTRIBUTES);
 
         // Uncomment if an existing type changed serialization format. Mappings for argument type keys can also be defined in mapping files
-        /*final CommandRewriter1_19_4<ClientboundPackets1_20_5> commandRewriter = new CommandRewriter1_19_4<ClientboundPackets1_20_5>(this) {
+        /*new CommandRewriter1_19_4<>(this) {
             @Override
-            public void handleArgument(final PacketWrapper wrapper, final String argumentType) throws Exception {
+            public void handleArgument(final PacketWrapper wrapper, final String argumentType) {
                 if (argumentType.equals("minecraft:abc")) {
                     // New argument
-                    wrapper.write(Type.INT, 0);
+                    wrapper.write(Types.INT, 0);
                 } else {
                     super.handleArgument(wrapper, argumentType);
                 }
             }
-        }.registerDeclareCommands1_19(ClientboundPackets1_20_5.DECLARE_COMMANDS);*/
-
-        // TODO Rewrite structured data ids and items within them
-
+        }.registerDeclareCommands1_19(ClientboundPackets1_21.COMMANDS);*/
     }
 
     @Override
@@ -95,7 +90,7 @@ public final class Protocol1_99To_98 extends AbstractProtocol<ClientboundPacket1
         // EntityTypes1_20_5.initialize(this);
 
         // Uncomment if a new particle was added = ids shifted; requires a new Types_ class copied from the last
-        /*Types1_20_5.PARTICLE.filler(this)
+        /*Types1_21.PARTICLE.filler(this)
                 .reader("block", ParticleType.Readers.BLOCK)
                 .reader("block_marker", ParticleType.Readers.BLOCK)
                 .reader("dust", ParticleType.Readers.DUST)
@@ -133,17 +128,17 @@ public final class Protocol1_99To_98 extends AbstractProtocol<ClientboundPacket1
     }
 
     @Override
-    public TagRewriter<ClientboundPacket1_20_5> getTagRewriter() {
+    public TagRewriter<ClientboundPacket1_21> getTagRewriter() {
         return tagRewriter;
     }
 
     @Override
-    protected PacketTypesProvider<ClientboundPacket1_20_5, ClientboundPacket1_20_5, ServerboundPacket1_20_5, ServerboundPacket1_20_5> createPacketTypesProvider() {
+    protected PacketTypesProvider<ClientboundPacket1_21, ClientboundPacket1_21, ServerboundPacket1_20_5, ServerboundPacket1_20_5> createPacketTypesProvider() {
         return new SimplePacketTypesProvider<>(
-            packetTypeMap(unmappedClientboundPacketType, ClientboundPackets1_20_5.class, ClientboundConfigurationPackets1_20_5.class),
-            packetTypeMap(mappedClientboundPacketType, ClientboundPackets1_20_5.class, ClientboundConfigurationPackets1_20_5.class),
+            packetTypeMap(unmappedClientboundPacketType, ClientboundPackets1_21.class, ClientboundConfigurationPackets1_21.class),
+            packetTypeMap(mappedClientboundPacketType, ClientboundPackets1_21.class, ClientboundConfigurationPackets1_21.class),
             packetTypeMap(mappedServerboundPacketType, ServerboundPackets1_20_5.class, ServerboundConfigurationPackets1_20_5.class),
             packetTypeMap(unmappedServerboundPacketType, ServerboundPackets1_20_5.class, ServerboundConfigurationPackets1_20_5.class)
         );
     }
-}
+}