Merge pull request #351 from VelocityPowered/future/1.16.2-velocity-1.1.0

[Future] 1.16.2 for Velocity 1.1.0

api/src/main/java/com/velocitypowered/api/network/ProtocolVersion.java

@@ -38,7 +38,8 @@ public enum ProtocolVersion {
   MINECRAFT_1_15_1(575, "1.15.1"),
   MINECRAFT_1_15_2(578, "1.15.2"),
   MINECRAFT_1_16(735, "1.16"),
-  MINECRAFT_1_16_1(736, "1.16.1");
+  MINECRAFT_1_16_1(736, "1.16.1"),
+  MINECRAFT_1_16_2(751, "1.16.2");
 
   private final int protocol;
   private final String name;

proxy/build.gradle

@@ -63,7 +63,7 @@ dependencies {
 
     compile 'it.unimi.dsi:fastutil:8.2.3'
     compile 'net.kyori:event-method-asm:4.0.0-SNAPSHOT'
-    compile 'net.kyori:nbt:1.12-1.0.0-SNAPSHOT'
+    compile 'net.kyori:adventure-nbt:4.0.0-SNAPSHOT'
 
     compile 'com.mojang:brigadier:1.0.17'
 

proxy/src/main/java/com/velocitypowered/proxy/VelocityServer.java

@@ -32,6 +32,7 @@ import com.velocitypowered.proxy.console.VelocityConsole;
 import com.velocitypowered.proxy.network.ConnectionManager;
 import com.velocitypowered.proxy.plugin.VelocityEventManager;
 import com.velocitypowered.proxy.plugin.VelocityPluginManager;
+import com.velocitypowered.proxy.protocol.ProtocolUtils;
 import com.velocitypowered.proxy.protocol.packet.Chat;
 import com.velocitypowered.proxy.protocol.util.FaviconSerializer;
 import com.velocitypowered.proxy.protocol.util.GameProfileSerializer;
@@ -91,13 +92,14 @@ public class VelocityServer implements ProxyServer, ForwardingAudience {
       .registerTypeHierarchyAdapter(Favicon.class, new FaviconSerializer())
       .registerTypeHierarchyAdapter(GameProfile.class, new GameProfileSerializer())
       .create();
-  private static final Gson PRE_1_16_PING_SERIALIZER = GsonComponentSerializer
+  private static final Gson PRE_1_16_PING_SERIALIZER = ProtocolUtils
-      .colorDownsamplingGson()
+      .getJsonChatSerializer(ProtocolVersion.MINECRAFT_1_15_2)
       .serializer()
       .newBuilder()
       .registerTypeHierarchyAdapter(Favicon.class, new FaviconSerializer())
       .create();
-  private static final Gson POST_1_16_PING_SERIALIZER = GsonComponentSerializer.gson()
+  private static final Gson POST_1_16_PING_SERIALIZER = ProtocolUtils
+      .getJsonChatSerializer(ProtocolVersion.MINECRAFT_1_16)
       .serializer()
       .newBuilder()
       .registerTypeHierarchyAdapter(Favicon.class, new FaviconSerializer())

proxy/src/main/java/com/velocitypowered/proxy/connection/client/ClientPlaySessionHandler.java

@@ -336,15 +336,16 @@ public class ClientPlaySessionHandler implements MinecraftSessionHandler {
         int tempDim = joinGame.getDimension() == 0 ? -1 : 0;
         player.getConnection().delayedWrite(
                 new Respawn(tempDim, joinGame.getPartialHashedSeed(), joinGame.getDifficulty(),
-                        joinGame.getGamemode(), joinGame.getLevelType(),
+                    joinGame.getGamemode(), joinGame.getLevelType(),
-                        false, joinGame.getDimensionInfo(), joinGame.getPreviousGamemode()));
+                    false, joinGame.getDimensionInfo(), joinGame.getPreviousGamemode(),
+                    joinGame.getCurrentDimensionData()));
       }
 
       player.getConnection().delayedWrite(
           new Respawn(joinGame.getDimension(), joinGame.getPartialHashedSeed(),
               joinGame.getDifficulty(), joinGame.getGamemode(), joinGame.getLevelType(),
-                  false, joinGame.getDimensionInfo(), joinGame.getPreviousGamemode()));
+              false, joinGame.getDimensionInfo(), joinGame.getPreviousGamemode(),
-
+              joinGame.getCurrentDimensionData()));
       destination.setActiveDimensionRegistry(joinGame.getDimensionRegistry()); // 1.16
     }
 

proxy/src/main/java/com/velocitypowered/proxy/connection/registry/DimensionData.java

@@ -1,11 +1,15 @@
 package com.velocitypowered.proxy.connection.registry;
 
 import com.google.common.base.Preconditions;
-import net.kyori.nbt.CompoundTag;
+import com.velocitypowered.api.network.ProtocolVersion;
+import net.kyori.adventure.nbt.CompoundBinaryTag;
 import org.checkerframework.checker.nullness.qual.Nullable;
 
 public final class DimensionData {
+  private static final String UNKNOWN_DIMENSION_ID = "velocity:unknown_dimension";
+
   private final String registryIdentifier;
+  private final @Nullable Integer dimensionId;
   private final boolean isNatural;
   private final float ambientLight;
   private final boolean isShrunk;
@@ -20,10 +24,13 @@ public final class DimensionData {
   private final String burningBehaviourIdentifier;
   private final @Nullable Long fixedTime;
   private final @Nullable Boolean createDragonFight;
+  private final @Nullable Double coordinateScale;
+  private final @Nullable String effects;
 
   /**
    * Initializes a new {@link DimensionData} instance.
    * @param registryIdentifier the identifier for the dimension from the registry.
+   * @param dimensionId the dimension ID contained in the registry (the "id" tag)
    * @param isNatural indicates if the dimension use natural world generation (e.g. overworld)
    * @param ambientLight the light level the client sees without external lighting
    * @param isShrunk indicates if the world is shrunk, aka not the full 256 blocks (e.g. nether)
@@ -38,24 +45,31 @@ public final class DimensionData {
    * @param burningBehaviourIdentifier the identifier for how burning blocks work in the dimension
    * @param fixedTime optional. If set to any game daytime value will deactivate time cycle
    * @param createDragonFight optional. Internal flag used in the end dimension
+   * @param coordinateScale optional, unknown purpose
+   * @param effects optional, unknown purpose
    */
-  public DimensionData(String registryIdentifier, boolean isNatural,
+  public DimensionData(String registryIdentifier,
-                       float ambientLight, boolean isShrunk, boolean isUltrawarm,
+      @Nullable Integer dimensionId,
-                       boolean hasCeiling, boolean hasSkylight,
+      boolean isNatural,
-                       boolean isPiglinSafe, boolean doBedsWork,
+      float ambientLight, boolean isShrunk, boolean isUltrawarm,
-                       boolean doRespawnAnchorsWork, boolean hasRaids,
+      boolean hasCeiling, boolean hasSkylight,
-                       int logicalHeight, String burningBehaviourIdentifier,
+      boolean isPiglinSafe, boolean doBedsWork,
-                       @Nullable Long fixedTime, @Nullable Boolean createDragonFight) {
+      boolean doRespawnAnchorsWork, boolean hasRaids,
+      int logicalHeight, String burningBehaviourIdentifier,
+      @Nullable Long fixedTime, @Nullable Boolean createDragonFight,
+      @Nullable Double coordinateScale,
+      @Nullable String effects) {
     Preconditions.checkNotNull(
-            registryIdentifier, "registryIdentifier cannot be null");
+        registryIdentifier, "registryIdentifier cannot be null");
     Preconditions.checkArgument(registryIdentifier.length() > 0,
-            "registryIdentifier cannot be empty");
+        "registryIdentifier cannot be empty");
     Preconditions.checkArgument(logicalHeight >= 0, "localHeight must be >= 0");
     Preconditions.checkNotNull(
-            burningBehaviourIdentifier, "burningBehaviourIdentifier cannot be null");
+        burningBehaviourIdentifier, "burningBehaviourIdentifier cannot be null");
     Preconditions.checkArgument(burningBehaviourIdentifier.length() > 0,
         "burningBehaviourIdentifier cannot be empty");
     this.registryIdentifier = registryIdentifier;
+    this.dimensionId = dimensionId;
     this.isNatural = isNatural;
     this.ambientLight = ambientLight;
     this.isShrunk = isShrunk;
@@ -70,12 +84,18 @@ public final class DimensionData {
     this.burningBehaviourIdentifier = burningBehaviourIdentifier;
     this.fixedTime = fixedTime;
     this.createDragonFight = createDragonFight;
+    this.coordinateScale = coordinateScale;
+    this.effects = effects;
   }
 
   public String getRegistryIdentifier() {
     return registryIdentifier;
   }
 
+  public @Nullable Integer getDimensionId() {
+    return dimensionId;
+  }
+
   public boolean isNatural() {
     return isNatural;
   }
@@ -132,61 +152,143 @@ public final class DimensionData {
     return createDragonFight;
   }
 
+  public @Nullable Double getCoordinateScale() {
+    return coordinateScale;
+  }
+
   /**
-   * Parses a given CompoundTag to a DimensionData instance.
+   * Returns a fresh {@link DimensionData} with the specified {@code registryIdentifier}
-   * @param toRead the compound from the registry to read
+   * and {@code dimensionId}.
+   *
+   * @param registryIdentifier the identifier for the dimension from the registry
+   * @param dimensionId optional, dimension ID
+   * @return a new {@link DimensionData}
+   */
+  public DimensionData annotateWith(String registryIdentifier,
+      @Nullable Integer dimensionId) {
+    return new DimensionData(registryIdentifier, dimensionId, isNatural, ambientLight, isShrunk,
+        isUltrawarm, hasCeiling, hasSkylight, isPiglinSafe, doBedsWork, doRespawnAnchorsWork,
+        hasRaids, logicalHeight, burningBehaviourIdentifier, fixedTime, createDragonFight,
+        coordinateScale, effects);
+  }
+
+  public boolean isUnannotated() {
+    return this.registryIdentifier.equalsIgnoreCase(UNKNOWN_DIMENSION_ID);
+  }
+
+  /**
+   * Parses a given CompoundTag to a DimensionData instance. Assumes the data only contains
+   * dimension details.
+   *
+   * @param details the compound from the registry to read
+   * @param version the protocol version
    * @return game dimension data
    */
-  public static DimensionData decodeCompoundTag(CompoundTag toRead) {
+  public static DimensionData decodeBaseCompoundTag(CompoundBinaryTag details,
-    Preconditions.checkNotNull(toRead, "CompoundTag cannot be null");
+      ProtocolVersion version) {
-    String registryIdentifier = toRead.getString("name");
+    boolean isNatural = details.getByte("natural") >= 1;
-    boolean isNatural = toRead.getBoolean("natural");
+    float ambientLight = details.getFloat("ambient_light");
-    float ambientLight = toRead.getFloat("ambient_light");
+    boolean isShrunk = details.getByte("shrunk") >= 1;
-    boolean isShrunk = toRead.getBoolean("shrunk");
+    boolean isUltrawarm = details.getByte("ultrawarm") >= 1;
-    boolean isUltrawarm = toRead.getBoolean("ultrawarm");
+    boolean hasCeiling = details.getByte("has_ceiling") >= 1;
-    boolean hasCeiling = toRead.getBoolean("has_ceiling");
+    boolean hasSkylight = details.getByte("has_skylight") >= 1;
-    boolean hasSkylight = toRead.getBoolean("has_skylight");
+    boolean isPiglinSafe = details.getByte("piglin_safe") >= 1;
-    boolean isPiglinSafe = toRead.getBoolean("piglin_safe");
+    boolean doBedsWork = details.getByte("bed_works") >= 1;
-    boolean doBedsWork = toRead.getBoolean("bed_works");
+    boolean doRespawnAnchorsWork = details.getByte("respawn_anchor_works") >= 1;
-    boolean doRespawnAnchorsWork = toRead.getBoolean("respawn_anchor_works");
+    boolean hasRaids = details.getByte("has_raids") >= 1;
-    boolean hasRaids = toRead.getBoolean("has_raids");
+    int logicalHeight = details.getInt("logical_height");
-    int logicalHeight = toRead.getInt("logical_height");
+    String burningBehaviourIdentifier = details.getString("infiniburn");
-    String burningBehaviourIdentifier = toRead.getString("infiniburn");
+    Long fixedTime = details.keySet().contains("fixed_time")
-    Long fixedTime = toRead.contains("fixed_time")
+        ? details.getLong("fixed_time") : null;
-            ? toRead.getLong("fixed_time") : null;
+    Boolean hasEnderdragonFight = details.keySet().contains("has_enderdragon_fight")
-    Boolean hasEnderdragonFight = toRead.contains("has_enderdragon_fight")
+        ? details.getByte("has_enderdragon_fight") >= 1 : null;
-                    ? toRead.getBoolean("has_enderdragon_fight") : null;
+    Double coordinateScale = details.keySet().contains("coordinate_scale")
+        ? details.getDouble("coordinate_scale") : null;
+    String effects = details.keySet().contains("effects") ? details.getString("effects")
+        : null;
     return new DimensionData(
-            registryIdentifier, isNatural, ambientLight, isShrunk,
+        UNKNOWN_DIMENSION_ID, null, isNatural, ambientLight, isShrunk,
-            isUltrawarm, hasCeiling, hasSkylight, isPiglinSafe, doBedsWork, doRespawnAnchorsWork,
+        isUltrawarm, hasCeiling, hasSkylight, isPiglinSafe, doBedsWork, doRespawnAnchorsWork,
-            hasRaids, logicalHeight, burningBehaviourIdentifier, fixedTime, hasEnderdragonFight);
+        hasRaids, logicalHeight, burningBehaviourIdentifier, fixedTime, hasEnderdragonFight,
+        coordinateScale, effects);
+  }
+
+  /**
+   * Parses a given CompoundTag to a DimensionData instance. Assumes the data is part of a
+   * dimension registry.
+   * @param dimTag the compound from the registry to read
+   * @param version the protocol version
+   * @return game dimension data
+   */
+  public static DimensionData decodeRegistryEntry(CompoundBinaryTag dimTag,
+      ProtocolVersion version) {
+    String registryIdentifier = dimTag.getString("name");
+    CompoundBinaryTag details;
+    Integer dimensionId = null;
+    if (version.compareTo(ProtocolVersion.MINECRAFT_1_16_2) >= 0) {
+      dimensionId = dimTag.getInt("id");
+      details = dimTag.getCompound("element");
+    } else {
+      details = dimTag;
+    }
+
+    DimensionData deserializedDetails = decodeBaseCompoundTag(details, version);
+    return deserializedDetails.annotateWith(registryIdentifier, dimensionId);
   }
 
   /**
    * Encodes the Dimension data as CompoundTag.
+   * @param version the version to serialize as
    * @return compound containing the dimension data
    */
-  public CompoundTag encodeAsCompundTag() {
+  public CompoundBinaryTag encodeAsCompoundTag(ProtocolVersion version) {
-    CompoundTag ret = new CompoundTag();
+    CompoundBinaryTag details = serializeDimensionDetails();
-    ret.putString("name", registryIdentifier);
+    if (version.compareTo(ProtocolVersion.MINECRAFT_1_16_2) >= 0) {
-    ret.putBoolean("natural", isNatural);
+      if (dimensionId == null) {
+        throw new IllegalStateException("Tried to serialize a 1.16.2+ dimension registry entry "
+            + "without an ID");
+      }
+
+      return CompoundBinaryTag.builder()
+          .putString("name", registryIdentifier)
+          .putInt("id", dimensionId)
+          .put("element", details)
+          .build();
+    } else {
+      return details.putString("name", registryIdentifier);
+    }
+  }
+
+  /**
+   * Serializes details of this dimension.
+   * @return serialized details of this dimension
+   */
+  public CompoundBinaryTag serializeDimensionDetails() {
+    CompoundBinaryTag.Builder ret = CompoundBinaryTag.builder();
+    ret.putByte("natural", (byte) (isNatural ? 1 : 0));
     ret.putFloat("ambient_light", ambientLight);
-    ret.putBoolean("shrunk", isShrunk);
+    ret.putByte("shrunk", (byte) (isShrunk ? 1 : 0));
-    ret.putBoolean("ultrawarm", isUltrawarm);
+    ret.putByte("ultrawarm", (byte) (isUltrawarm ? 1 : 0));
-    ret.putBoolean("has_ceiling", hasCeiling);
+    ret.putByte("has_ceiling", (byte) (hasCeiling ? 1 : 0));
-    ret.putBoolean("has_skylight", hasSkylight);
+    ret.putByte("has_skylight", (byte) (hasSkylight ? 1 : 0));
-    ret.putBoolean("piglin_safe", isPiglinSafe);
+    ret.putByte("piglin_safe", (byte) (isPiglinSafe ? 1 : 0));
-    ret.putBoolean("bed_works", doBedsWork);
+    ret.putByte("bed_works", (byte) (doBedsWork ? 1 : 0));
-    ret.putBoolean("respawn_anchor_works", doRespawnAnchorsWork);
+    ret.putByte("respawn_anchor_works", (byte) (doBedsWork ? 1 : 0));
-    ret.putBoolean("has_raids", hasRaids);
+    ret.putByte("has_raids", (byte) (hasRaids ? 1 : 0));
     ret.putInt("logical_height", logicalHeight);
     ret.putString("infiniburn", burningBehaviourIdentifier);
     if (fixedTime != null) {
       ret.putLong("fixed_time", fixedTime);
     }
     if (createDragonFight != null) {
-      ret.putBoolean("has_enderdragon_fight", createDragonFight);
+      ret.putByte("has_enderdragon_fight", (byte) (createDragonFight ? 1 : 0));
     }
-    return ret;
+    if (coordinateScale != null) {
+      ret.putDouble("coordinate_scale", coordinateScale);
+    }
+    if (effects != null) {
+      ret.putString("effects", effects);
+    }
+    return ret.build();
   }
 }

proxy/src/main/java/com/velocitypowered/proxy/connection/registry/DimensionInfo.java

@@ -1,6 +1,7 @@
 package com.velocitypowered.proxy.connection.registry;
 
 import com.google.common.base.Preconditions;
+import org.checkerframework.checker.nullness.qual.Nullable;
 
 public final class DimensionInfo {
 
@@ -16,18 +17,13 @@ public final class DimensionInfo {
    * @param isFlat if true will set world lighting below surface-level to not display fog
    * @param isDebugType if true constrains the world to the very limited debug-type world
    */
-  public DimensionInfo(String registryIdentifier, String levelName,
+  public DimensionInfo(String registryIdentifier, @Nullable String levelName,
-                       boolean isFlat, boolean isDebugType) {
+      boolean isFlat, boolean isDebugType) {
     this.registryIdentifier = Preconditions.checkNotNull(
-            registryIdentifier, "registryIdentifier cannot be null");
+        registryIdentifier, "registryIdentifier cannot be null");
-    Preconditions.checkArgument(
+    Preconditions.checkArgument(registryIdentifier.length() > 0,
-            registryIdentifier.length() > 0,
+        "registryIdentifier cannot be empty");
-            "registryIdentifier cannot be empty");
+    this.levelName = levelName;
-    this.levelName = Preconditions.checkNotNull(
-            levelName, "levelName cannot be null");
-    Preconditions.checkArgument(
-            levelName.length() > 0,
-            "registryIdentifier cannot be empty");
     this.isFlat = isFlat;
     this.isDebugType = isDebugType;
   }
@@ -40,7 +36,7 @@ public final class DimensionInfo {
     return isFlat;
   }
 
-  public String getLevelName() {
+  public @Nullable String getLevelName() {
     return levelName;
   }
 

proxy/src/main/java/com/velocitypowered/proxy/connection/registry/DimensionRegistry.java

@@ -4,16 +4,16 @@ import com.google.common.base.Preconditions;
 import com.google.common.collect.ImmutableSet;
 import com.google.common.collect.Maps;
 
+import com.velocitypowered.api.network.ProtocolVersion;
 import java.util.Map;
 import java.util.Set;
 
-import net.kyori.nbt.CompoundTag;
+import net.kyori.adventure.nbt.BinaryTag;
-import net.kyori.nbt.ListTag;
+import net.kyori.adventure.nbt.BinaryTagTypes;
-import net.kyori.nbt.Tag;
+import net.kyori.adventure.nbt.CompoundBinaryTag;
-import net.kyori.nbt.TagType;
+import net.kyori.adventure.nbt.ListBinaryTag;
 import org.checkerframework.checker.nullness.qual.Nullable;
 
-
 public final class DimensionRegistry {
 
   private final Map<String, DimensionData> registeredDimensions;
@@ -31,17 +31,17 @@ public final class DimensionRegistry {
    * @param levelNames a populated {@link ImmutableSet} of the level (world) names the server offers
    */
   public DimensionRegistry(ImmutableSet<DimensionData> registeredDimensions,
-                            ImmutableSet<String> levelNames) {
+      ImmutableSet<String> levelNames) {
     Preconditions.checkNotNull(registeredDimensions,
-            "registeredDimensions cannot be null");
+        "registeredDimensions cannot be null");
     Preconditions.checkNotNull(levelNames,
-            "levelNames cannot be null");
+        "levelNames cannot be null");
     Preconditions.checkArgument(registeredDimensions.size() > 0,
-            "registeredDimensions needs to be populated");
+        "registeredDimensions needs to be populated");
     Preconditions.checkArgument(levelNames.size() > 0,
-            "levelNames needs to populated");
+        "levelNames needs to populated");
     this.registeredDimensions = Maps.uniqueIndex(
-            registeredDimensions, DimensionData::getRegistryIdentifier);
+        registeredDimensions, DimensionData::getRegistryIdentifier);
     this.levelNames = levelNames;
   }
 
@@ -72,36 +72,33 @@ public final class DimensionRegistry {
       return false;
     }
     return registeredDimensions.containsKey(toValidate.getRegistryIdentifier())
-            && levelNames.contains(toValidate.getLevelName());
+        && levelNames.contains(toValidate.getLevelName());
   }
 
   /**
    * Encodes the stored Dimension registry as CompoundTag.
    * @return the CompoundTag containing identifier:type mappings
    */
-  public CompoundTag encodeRegistry() {
+  public ListBinaryTag encodeRegistry(ProtocolVersion version) {
-    CompoundTag ret = new CompoundTag();
+    ListBinaryTag.Builder<CompoundBinaryTag> listBuilder = ListBinaryTag
-    ListTag list = new ListTag(TagType.COMPOUND);
+        .builder(BinaryTagTypes.COMPOUND);
     for (DimensionData iter : registeredDimensions.values()) {
-      list.add(iter.encodeAsCompundTag());
+      listBuilder.add(iter.encodeAsCompoundTag(version));
     }
-    ret.put("dimension", list);
+    return listBuilder.build();
-    return ret;
   }
 
   /**
    * Decodes a CompoundTag storing a dimension registry.
    * @param toParse CompoundTag containing a dimension registry
    */
-  public static ImmutableSet<DimensionData> fromGameData(CompoundTag toParse) {
+  public static ImmutableSet<DimensionData> fromGameData(ListBinaryTag toParse,
-    Preconditions.checkNotNull(toParse, "CompoundTag cannot be null");
+      ProtocolVersion version) {
-    Preconditions.checkArgument(toParse.contains("dimension", TagType.LIST),
+    Preconditions.checkNotNull(toParse, "ListTag cannot be null");
-            "CompoundTag does not contain a dimension list");
-    ListTag dimensions = toParse.getList("dimension");
     ImmutableSet.Builder<DimensionData> mappings = ImmutableSet.builder();
-    for (Tag iter : dimensions) {
+    for (BinaryTag iter : toParse) {
-      if (iter instanceof CompoundTag) {
+      if (iter instanceof CompoundBinaryTag) {
-        mappings.add(DimensionData.decodeCompoundTag((CompoundTag) iter));
+        mappings.add(DimensionData.decodeRegistryEntry((CompoundBinaryTag) iter, version));
       }
     }
     return mappings.build();

proxy/src/main/java/com/velocitypowered/proxy/protocol/ProtocolUtils.java

@@ -3,10 +3,10 @@ package com.velocitypowered.proxy.protocol;
 import static com.google.common.base.Preconditions.checkArgument;
 import static com.velocitypowered.proxy.protocol.util.NettyPreconditions.checkFrame;
 
-import com.google.common.base.Preconditions;
 import com.velocitypowered.api.network.ProtocolVersion;
 import com.velocitypowered.api.util.GameProfile;
 import com.velocitypowered.proxy.protocol.netty.MinecraftDecoder;
+import com.velocitypowered.proxy.protocol.util.VelocityLegacyHoverEventSerializer;
 import com.velocitypowered.proxy.util.except.QuietDecoderException;
 import io.netty.buffer.ByteBuf;
 import io.netty.buffer.ByteBufInputStream;
@@ -22,12 +22,24 @@ import java.util.ArrayList;
 import java.util.List;
 import java.util.UUID;
 
+import net.kyori.adventure.nbt.BinaryTagIO;
+import net.kyori.adventure.nbt.CompoundBinaryTag;
 import net.kyori.adventure.text.serializer.gson.GsonComponentSerializer;
-import net.kyori.nbt.CompoundTag;
-import net.kyori.nbt.TagIO;
 
 public enum ProtocolUtils {
   ;
+
+  private static final GsonComponentSerializer PRE_1_16_SERIALIZER =
+      GsonComponentSerializer.builder()
+          .downsampleColors()
+          .emitLegacyHoverEvent()
+          .legacyHoverEventSerializer(VelocityLegacyHoverEventSerializer.INSTANCE)
+          .build();
+  private static final GsonComponentSerializer MODERN_SERIALIZER =
+      GsonComponentSerializer.builder()
+          .legacyHoverEventSerializer(VelocityLegacyHoverEventSerializer.INSTANCE)
+          .build();
+
   private static final int DEFAULT_MAX_STRING_SIZE = 65536; // 64KiB
   private static final QuietDecoderException BAD_VARINT_CACHED =
       new QuietDecoderException("Bad varint decoded");
@@ -219,11 +231,11 @@ public enum ProtocolUtils {
   }
 
   /**
-   * Reads a {@link net.kyori.nbt.CompoundTag} from the {@code buf}.
+   * Reads a {@link net.kyori.adventure.nbt.CompoundBinaryTag} from the {@code buf}.
    * @param buf the buffer to read from
-   * @return {@link net.kyori.nbt.CompoundTag} the CompoundTag from the buffer
+   * @return {@link net.kyori.adventure.nbt.CompoundBinaryTag} the CompoundTag from the buffer
    */
-  public static CompoundTag readCompoundTag(ByteBuf buf) {
+  public static CompoundBinaryTag readCompoundTag(ByteBuf buf) {
     int indexBefore = buf.readerIndex();
     byte startType = buf.readByte();
     if (startType == 0) {
@@ -231,7 +243,7 @@ public enum ProtocolUtils {
     }
     buf.readerIndex(indexBefore);
     try {
-      return TagIO.readDataInput(new ByteBufInputStream(buf));
+      return BinaryTagIO.readDataInput(new ByteBufInputStream(buf));
     } catch (IOException thrown) {
       throw new DecoderException(
               "Unable to parse NBT CompoundTag, full error: " + thrown.getMessage());
@@ -243,13 +255,13 @@ public enum ProtocolUtils {
    * @param buf the buffer to write to
    * @param compoundTag the CompoundTag to write
    */
-  public static void writeCompoundTag(ByteBuf buf, CompoundTag compoundTag) {
+  public static void writeCompoundTag(ByteBuf buf, CompoundBinaryTag compoundTag) {
     if (compoundTag == null) {
       buf.writeByte(0);
       return;
     }
     try {
-      TagIO.writeDataOutput(compoundTag, new ByteBufOutputStream(buf));
+      BinaryTagIO.writeDataOutput(compoundTag, new ByteBufOutputStream(buf));
     } catch (IOException e) {
       throw new EncoderException("Unable to encode NBT CompoundTag");
     }
@@ -468,9 +480,9 @@ public enum ProtocolUtils {
    */
   public static GsonComponentSerializer getJsonChatSerializer(ProtocolVersion version) {
     if (version.compareTo(ProtocolVersion.MINECRAFT_1_16) >= 0) {
-      return GsonComponentSerializer.gson();
+      return MODERN_SERIALIZER;
     }
-    return GsonComponentSerializer.colorDownsamplingGson();
+    return PRE_1_16_SERIALIZER;
   }
 
   public enum Direction {

proxy/src/main/java/com/velocitypowered/proxy/protocol/StateRegistry.java

@@ -7,6 +7,7 @@ import static com.velocitypowered.api.network.ProtocolVersion.MINECRAFT_1_13;
 import static com.velocitypowered.api.network.ProtocolVersion.MINECRAFT_1_14;
 import static com.velocitypowered.api.network.ProtocolVersion.MINECRAFT_1_15;
 import static com.velocitypowered.api.network.ProtocolVersion.MINECRAFT_1_16;
+import static com.velocitypowered.api.network.ProtocolVersion.MINECRAFT_1_16_2;
 import static com.velocitypowered.api.network.ProtocolVersion.MINECRAFT_1_7_2;
 import static com.velocitypowered.api.network.ProtocolVersion.MINECRAFT_1_8;
 import static com.velocitypowered.api.network.ProtocolVersion.MINECRAFT_1_9;
@@ -121,7 +122,8 @@ public enum StateRegistry {
           map(0x18, MINECRAFT_1_12, false),
           map(0x1D, MINECRAFT_1_13, false),
           map(0x1F, MINECRAFT_1_14, false),
-          map(0x20, MINECRAFT_1_16, false));
+          map(0x20, MINECRAFT_1_16, false),
+          map(0x21, MINECRAFT_1_16_2, false));
 
       clientbound.register(BossBar.class, BossBar::new,
           map(0x0C, MINECRAFT_1_9, false),
@@ -138,39 +140,45 @@ public enum StateRegistry {
           map(0x0E, MINECRAFT_1_9, false),
           map(0x10, MINECRAFT_1_13, false),
           map(0x11, MINECRAFT_1_15, false),
-          map(0x10, MINECRAFT_1_16, false));
+          map(0x10, MINECRAFT_1_16, false),
+          map(0x0F, MINECRAFT_1_16_2, false));
       clientbound.register(AvailableCommands.class, AvailableCommands::new,
           map(0x11, MINECRAFT_1_13, false),
           map(0x12, MINECRAFT_1_15, false),
-          map(0x11, MINECRAFT_1_16, false));
+          map(0x11, MINECRAFT_1_16, false),
+          map(0x10, MINECRAFT_1_16_2, false));
       clientbound.register(PluginMessage.class, PluginMessage::new,
           map(0x3F, MINECRAFT_1_7_2, false),
           map(0x18, MINECRAFT_1_9, false),
           map(0x19, MINECRAFT_1_13, false),
           map(0x18, MINECRAFT_1_14, false),
           map(0x19, MINECRAFT_1_15, false),
-          map(0x18, MINECRAFT_1_16, false));
+          map(0x18, MINECRAFT_1_16, false),
+          map(0x17, MINECRAFT_1_16_2, false));
       clientbound.register(Disconnect.class, Disconnect::new,
           map(0x40, MINECRAFT_1_7_2, false),
           map(0x1A, MINECRAFT_1_9, false),
           map(0x1B, MINECRAFT_1_13, false),
           map(0x1A, MINECRAFT_1_14, false),
           map(0x1B, MINECRAFT_1_15, false),
-          map(0x1A, MINECRAFT_1_16, false));
+          map(0x1A, MINECRAFT_1_16, false),
+          map(0x19, MINECRAFT_1_16_2, false));
       clientbound.register(KeepAlive.class, KeepAlive::new,
           map(0x00, MINECRAFT_1_7_2, false),
           map(0x1F, MINECRAFT_1_9, false),
           map(0x21, MINECRAFT_1_13, false),
           map(0x20, MINECRAFT_1_14, false),
           map(0x21, MINECRAFT_1_15, false),
-          map(0x20, MINECRAFT_1_16, false));
+          map(0x20, MINECRAFT_1_16, false),
+          map(0x1F, MINECRAFT_1_16_2, false));
       clientbound.register(JoinGame.class, JoinGame::new,
           map(0x01, MINECRAFT_1_7_2, false),
           map(0x23, MINECRAFT_1_9, false),
           map(0x25, MINECRAFT_1_13, false),
           map(0x25, MINECRAFT_1_14, false),
           map(0x26, MINECRAFT_1_15, false),
-          map(0x25, MINECRAFT_1_16, false));
+          map(0x25, MINECRAFT_1_16, false),
+          map(0x24, MINECRAFT_1_16_2, false));
       clientbound.register(Respawn.class, Respawn::new,
           map(0x07, MINECRAFT_1_7_2, true),
           map(0x33, MINECRAFT_1_9, true),
@@ -179,7 +187,8 @@ public enum StateRegistry {
           map(0x38, MINECRAFT_1_13, true),
           map(0x3A, MINECRAFT_1_14, true),
           map(0x3B, MINECRAFT_1_15, true),
-          map(0x3A, MINECRAFT_1_16, true));
+          map(0x3A, MINECRAFT_1_16, true),
+          map(0x39, MINECRAFT_1_16_2, true));
       clientbound.register(ResourcePackRequest.class, ResourcePackRequest::new,
           map(0x48, MINECRAFT_1_8, true),
           map(0x32, MINECRAFT_1_9, true),
@@ -188,7 +197,8 @@ public enum StateRegistry {
           map(0x37, MINECRAFT_1_13, true),
           map(0x39, MINECRAFT_1_14, true),
           map(0x3A, MINECRAFT_1_15, true),
-          map(0x39, MINECRAFT_1_16, true));
+          map(0x39, MINECRAFT_1_16, true),
+          map(0x38, MINECRAFT_1_16_2, true));
       clientbound.register(HeaderAndFooter.class, HeaderAndFooter::new,
           map(0x47, MINECRAFT_1_8, true),
           map(0x48, MINECRAFT_1_9, true),
@@ -215,7 +225,8 @@ public enum StateRegistry {
           map(0x30, MINECRAFT_1_13, false),
           map(0x33, MINECRAFT_1_14, false),
           map(0x34, MINECRAFT_1_15, false),
-          map(0x33, MINECRAFT_1_16, false));
+          map(0x33, MINECRAFT_1_16, false),
+          map(0x32, MINECRAFT_1_16_2, false));
     }
   },
   LOGIN {

proxy/src/main/java/com/velocitypowered/proxy/protocol/packet/JoinGame.java

@@ -8,6 +8,9 @@ import com.velocitypowered.proxy.connection.registry.DimensionInfo;
 import com.velocitypowered.proxy.connection.registry.DimensionRegistry;
 import com.velocitypowered.proxy.protocol.*;
 import io.netty.buffer.ByteBuf;
+import net.kyori.adventure.nbt.BinaryTagTypes;
+import net.kyori.adventure.nbt.CompoundBinaryTag;
+import net.kyori.adventure.nbt.ListBinaryTag;
 import org.checkerframework.checker.nullness.qual.Nullable;
 
 public class JoinGame implements MinecraftPacket {
@@ -17,14 +20,17 @@ public class JoinGame implements MinecraftPacket {
   private int dimension;
   private long partialHashedSeed; // 1.15+
   private short difficulty;
-  private short maxPlayers;
+  private boolean isHardcore;
+  private int maxPlayers;
   private @Nullable String levelType;
   private int viewDistance; // 1.14+
   private boolean reducedDebugInfo;
   private boolean showRespawnScreen;
   private DimensionRegistry dimensionRegistry; // 1.16+
   private DimensionInfo dimensionInfo; // 1.16+
+  private DimensionData currentDimensionData; // 1.16.2+
   private short previousGamemode; // 1.16+
+  private CompoundBinaryTag biomeRegistry; // 1.16.2+
 
   public int getEntityId() {
     return entityId;
@@ -62,11 +68,11 @@ public class JoinGame implements MinecraftPacket {
     this.difficulty = difficulty;
   }
 
-  public short getMaxPlayers() {
+  public int getMaxPlayers() {
     return maxPlayers;
   }
 
-  public void setMaxPlayers(short maxPlayers) {
+  public void setMaxPlayers(int maxPlayers) {
     this.maxPlayers = maxPlayers;
   }
 
@@ -118,6 +124,26 @@ public class JoinGame implements MinecraftPacket {
     this.previousGamemode = previousGamemode;
   }
 
+  public boolean getIsHardcore() {
+    return isHardcore;
+  }
+
+  public void setIsHardcore(boolean isHardcore) {
+    this.isHardcore = isHardcore;
+  }
+
+  public CompoundBinaryTag getBiomeRegistry() {
+    return biomeRegistry;
+  }
+
+  public void setBiomeRegistry(CompoundBinaryTag biomeRegistry) {
+    this.biomeRegistry = biomeRegistry;
+  }
+
+  public DimensionData getCurrentDimensionData() {
+    return currentDimensionData;
+  }
+
   @Override
   public String toString() {
     return "JoinGame{"
@@ -139,16 +165,41 @@ public class JoinGame implements MinecraftPacket {
   @Override
   public void decode(ByteBuf buf, ProtocolUtils.Direction direction, ProtocolVersion version) {
     this.entityId = buf.readInt();
-    this.gamemode = buf.readUnsignedByte();
+    if (version.compareTo(ProtocolVersion.MINECRAFT_1_16_2) >= 0) {
+      this.isHardcore = buf.readBoolean();
+      this.gamemode = buf.readByte();
+    } else {
+      this.gamemode = buf.readByte();
+      this.isHardcore = (this.gamemode & 0x08) != 0;
+      this.gamemode &= ~0x08;
+    }
     String dimensionIdentifier = null;
     String levelName = null;
     if (version.compareTo(ProtocolVersion.MINECRAFT_1_16) >= 0) {
       this.previousGamemode = buf.readByte();
       ImmutableSet<String> levelNames = ImmutableSet.copyOf(ProtocolUtils.readStringArray(buf));
-      ImmutableSet<DimensionData> readData = DimensionRegistry.fromGameData(ProtocolUtils.readCompoundTag(buf));
+      CompoundBinaryTag registryContainer = ProtocolUtils.readCompoundTag(buf);
+      ListBinaryTag dimensionRegistryContainer = null;
+      if (version.compareTo(ProtocolVersion.MINECRAFT_1_16_2) >= 0) {
+        dimensionRegistryContainer = registryContainer.getCompound("minecraft:dimension_type")
+            .getList("value", BinaryTagTypes.COMPOUND);
+        this.biomeRegistry = registryContainer.getCompound("minecraft:worldgen/biome");
+      } else {
+        dimensionRegistryContainer = registryContainer.getList("dimension",
+            BinaryTagTypes.COMPOUND);
+      }
+      ImmutableSet<DimensionData> readData =
+          DimensionRegistry.fromGameData(dimensionRegistryContainer, version);
       this.dimensionRegistry = new DimensionRegistry(readData, levelNames);
-      dimensionIdentifier = ProtocolUtils.readString(buf);
+      if (version.compareTo(ProtocolVersion.MINECRAFT_1_16_2) >= 0) {
-      levelName = ProtocolUtils.readString(buf);
+        CompoundBinaryTag currentDimDataTag = ProtocolUtils.readCompoundTag(buf);
+        dimensionIdentifier = ProtocolUtils.readString(buf);
+        this.currentDimensionData = DimensionData.decodeBaseCompoundTag(currentDimDataTag, version)
+            .annotateWith(dimensionIdentifier, null);
+      } else {
+        dimensionIdentifier = ProtocolUtils.readString(buf);
+        levelName = ProtocolUtils.readString(buf);
+      }
     } else if (version.compareTo(ProtocolVersion.MINECRAFT_1_9_1) >= 0) {
       this.dimension = buf.readInt();
     } else {
@@ -160,7 +211,11 @@ public class JoinGame implements MinecraftPacket {
     if (version.compareTo(ProtocolVersion.MINECRAFT_1_15) >= 0) {
       this.partialHashedSeed = buf.readLong();
     }
-    this.maxPlayers = buf.readUnsignedByte();
+    if (version.compareTo(ProtocolVersion.MINECRAFT_1_16_2) >= 0) {
+      this.maxPlayers = ProtocolUtils.readVarInt(buf);
+    } else {
+      this.maxPlayers = buf.readUnsignedByte();
+    }
     if (version.compareTo(ProtocolVersion.MINECRAFT_1_16) < 0) {
       this.levelType = ProtocolUtils.readString(buf, 16);
     }
@@ -183,14 +238,35 @@ public class JoinGame implements MinecraftPacket {
   @Override
   public void encode(ByteBuf buf, ProtocolUtils.Direction direction, ProtocolVersion version) {
     buf.writeInt(entityId);
-    buf.writeByte(gamemode);
+    if (version.compareTo(ProtocolVersion.MINECRAFT_1_16_2) >= 0) {
+      buf.writeBoolean(isHardcore);
+      buf.writeByte(gamemode);
+    } else {
+      buf.writeByte(isHardcore ? gamemode | 0x8 : gamemode);
+    }
     if (version.compareTo(ProtocolVersion.MINECRAFT_1_16) >= 0) {
       buf.writeByte(previousGamemode);
       ProtocolUtils.writeStringArray(buf, dimensionRegistry.getLevelNames().toArray(
-              new String[dimensionRegistry.getLevelNames().size()]));
+          new String[dimensionRegistry.getLevelNames().size()]));
-      ProtocolUtils.writeCompoundTag(buf, dimensionRegistry.encodeRegistry());
+      CompoundBinaryTag.Builder registryContainer = CompoundBinaryTag.builder();
-      ProtocolUtils.writeString(buf, dimensionInfo.getRegistryIdentifier());
+      ListBinaryTag encodedDimensionRegistry = dimensionRegistry.encodeRegistry(version);
-      ProtocolUtils.writeString(buf, dimensionInfo.getLevelName());
+      if (version.compareTo(ProtocolVersion.MINECRAFT_1_16_2) >= 0) {
+        CompoundBinaryTag.Builder dimensionRegistryDummy = CompoundBinaryTag.builder();
+        dimensionRegistryDummy.putString("type", "minecraft:dimension_type");
+        dimensionRegistryDummy.put("value", encodedDimensionRegistry);
+        registryContainer.put("minecraft:dimension_type", dimensionRegistryDummy.build());
+        registryContainer.put("minecraft:worldgen/biome", biomeRegistry);
+      } else {
+        registryContainer.put("dimension", encodedDimensionRegistry);
+      }
+      ProtocolUtils.writeCompoundTag(buf, registryContainer.build());
+      if (version.compareTo(ProtocolVersion.MINECRAFT_1_16_2) >= 0) {
+        ProtocolUtils.writeCompoundTag(buf, currentDimensionData.serializeDimensionDetails());
+        ProtocolUtils.writeString(buf, dimensionInfo.getRegistryIdentifier());
+      } else {
+        ProtocolUtils.writeString(buf, dimensionInfo.getRegistryIdentifier());
+        ProtocolUtils.writeString(buf, dimensionInfo.getLevelName());
+      }
     } else if (version.compareTo(ProtocolVersion.MINECRAFT_1_9_1) >= 0) {
       buf.writeInt(dimension);
     } else {
@@ -202,7 +278,11 @@ public class JoinGame implements MinecraftPacket {
     if (version.compareTo(ProtocolVersion.MINECRAFT_1_15) >= 0) {
       buf.writeLong(partialHashedSeed);
     }
-    buf.writeByte(maxPlayers);
+    if (version.compareTo(ProtocolVersion.MINECRAFT_1_16_2) >= 0) {
+      ProtocolUtils.writeVarInt(buf, maxPlayers);
+    } else {
+      buf.writeByte(maxPlayers);
+    }
     if (version.compareTo(ProtocolVersion.MINECRAFT_1_16) < 0) {
       if (levelType == null) {
         throw new IllegalStateException("No level type specified.");

proxy/src/main/java/com/velocitypowered/proxy/protocol/packet/Respawn.java

@@ -2,10 +2,12 @@ package com.velocitypowered.proxy.protocol.packet;
 
 import com.velocitypowered.api.network.ProtocolVersion;
 import com.velocitypowered.proxy.connection.MinecraftSessionHandler;
+import com.velocitypowered.proxy.connection.registry.DimensionData;
 import com.velocitypowered.proxy.connection.registry.DimensionInfo;
 import com.velocitypowered.proxy.protocol.MinecraftPacket;
 import com.velocitypowered.proxy.protocol.ProtocolUtils;
 import io.netty.buffer.ByteBuf;
+import net.kyori.adventure.nbt.CompoundBinaryTag;
 
 public class Respawn implements MinecraftPacket {
 
@@ -15,15 +17,16 @@ public class Respawn implements MinecraftPacket {
   private short gamemode;
   private String levelType = "";
   private boolean shouldKeepPlayerData; // 1.16+
-  private DimensionInfo dimensionInfo; // 1.16+
+  private DimensionInfo dimensionInfo; // 1.16-1.16.1
   private short previousGamemode; // 1.16+
+  private DimensionData currentDimensionData; // 1.16.2+
 
   public Respawn() {
   }
 
   public Respawn(int dimension, long partialHashedSeed, short difficulty, short gamemode,
       String levelType, boolean shouldKeepPlayerData, DimensionInfo dimensionInfo,
-                 short previousGamemode) {
+      short previousGamemode, DimensionData currentDimensionData) {
     this.dimension = dimension;
     this.partialHashedSeed = partialHashedSeed;
     this.difficulty = difficulty;
@@ -32,6 +35,7 @@ public class Respawn implements MinecraftPacket {
     this.shouldKeepPlayerData = shouldKeepPlayerData;
     this.dimensionInfo = dimensionInfo;
     this.previousGamemode = previousGamemode;
+    this.currentDimensionData = currentDimensionData;
   }
 
   public int getDimension() {
@@ -100,7 +104,9 @@ public class Respawn implements MinecraftPacket {
         + ", levelType='" + levelType + '\''
         + ", shouldKeepPlayerData=" + shouldKeepPlayerData
         + ", dimensionRegistryName='" + dimensionInfo.toString() + '\''
+        + ", dimensionInfo=" + dimensionInfo
         + ", previousGamemode=" + previousGamemode
+        + ", dimensionData=" + currentDimensionData
         + '}';
   }
 
@@ -109,8 +115,15 @@ public class Respawn implements MinecraftPacket {
     String dimensionIdentifier = null;
     String levelName = null;
     if (version.compareTo(ProtocolVersion.MINECRAFT_1_16) >= 0) {
-      dimensionIdentifier = ProtocolUtils.readString(buf);
+      if (version.compareTo(ProtocolVersion.MINECRAFT_1_16_2) >= 0) {
-      levelName = ProtocolUtils.readString(buf);
+        CompoundBinaryTag dimDataTag = ProtocolUtils.readCompoundTag(buf);
+        dimensionIdentifier = ProtocolUtils.readString(buf);
+        this.currentDimensionData = DimensionData.decodeBaseCompoundTag(dimDataTag, version)
+            .annotateWith(dimensionIdentifier, null);
+      } else {
+        dimensionIdentifier = ProtocolUtils.readString(buf);
+        levelName = ProtocolUtils.readString(buf);
+      }
     } else {
       this.dimension = buf.readInt();
     }
@@ -135,8 +148,13 @@ public class Respawn implements MinecraftPacket {
   @Override
   public void encode(ByteBuf buf, ProtocolUtils.Direction direction, ProtocolVersion version) {
     if (version.compareTo(ProtocolVersion.MINECRAFT_1_16) >= 0) {
-      ProtocolUtils.writeString(buf, dimensionInfo.getRegistryIdentifier());
+      if (version.compareTo(ProtocolVersion.MINECRAFT_1_16_2) >= 0) {
-      ProtocolUtils.writeString(buf, dimensionInfo.getLevelName());
+        ProtocolUtils.writeCompoundTag(buf, currentDimensionData.serializeDimensionDetails());
+        ProtocolUtils.writeString(buf, dimensionInfo.getRegistryIdentifier());
+      } else {
+        ProtocolUtils.writeString(buf, dimensionInfo.getRegistryIdentifier());
+        ProtocolUtils.writeString(buf, dimensionInfo.getLevelName());
+      }
     } else {
       buf.writeInt(dimension);
     }

proxy/src/main/java/com/velocitypowered/proxy/protocol/packet/brigadier/ArgumentPropertyRegistry.java

@@ -135,5 +135,6 @@ public class ArgumentPropertyRegistry {
     dummy("minecraft:float_range", DUMMY);
     dummy("minecraft:time", DUMMY); // added in 1.14
     dummy("minecraft:uuid", DUMMY); // added in 1.16
+    dummy("minecraft:angle", DUMMY); // added in 1.16.2
   }
 }

proxy/src/main/java/com/velocitypowered/proxy/protocol/util/VelocityLegacyHoverEventSerializer.java

@@ -0,0 +1,104 @@
+package com.velocitypowered.proxy.protocol.util;
+
+import java.io.IOException;
+import java.util.UUID;
+import net.kyori.adventure.key.Key;
+import net.kyori.adventure.nbt.CompoundBinaryTag;
+import net.kyori.adventure.nbt.TagStringIO;
+import net.kyori.adventure.nbt.api.BinaryTagHolder;
+import net.kyori.adventure.text.Component;
+import net.kyori.adventure.text.TextComponent;
+import net.kyori.adventure.text.event.HoverEvent;
+import net.kyori.adventure.text.event.HoverEvent.ShowEntity;
+import net.kyori.adventure.text.event.HoverEvent.ShowItem;
+import net.kyori.adventure.text.serializer.gson.LegacyHoverEventSerializer;
+import net.kyori.adventure.text.serializer.plain.PlainComponentSerializer;
+import net.kyori.adventure.util.Codec.Decoder;
+import net.kyori.adventure.util.Codec.Encoder;
+import org.checkerframework.checker.nullness.qual.NonNull;
+
+/**
+ * An implementation of {@link LegacyHoverEventSerializer} that implements the interface in the
+ * most literal, albeit "incompatible" way possible.
+ */
+public class VelocityLegacyHoverEventSerializer implements LegacyHoverEventSerializer {
+
+  public static final LegacyHoverEventSerializer INSTANCE =
+      new VelocityLegacyHoverEventSerializer();
+
+  private VelocityLegacyHoverEventSerializer() {
+
+  }
+
+  private static Key legacyIdToFakeKey(byte id) {
+    return Key.of("velocity", "legacy_hover/id_" + id);
+  }
+
+  @Override
+  public HoverEvent.@NonNull ShowItem deserializeShowItem(@NonNull Component input)
+      throws IOException {
+    String snbt = PlainComponentSerializer.plain().serialize(input);
+    CompoundBinaryTag item = TagStringIO.get().asCompound(snbt);
+
+    Key key;
+    String idIfString = item.getString("id", "");
+    if (idIfString.isEmpty()) {
+      key = legacyIdToFakeKey(item.getByte("id"));
+    } else {
+      key = Key.of(idIfString);
+    }
+
+    byte count = item.getByte("Count", (byte) 1);
+    return new ShowItem(key, count, BinaryTagHolder.of(snbt));
+  }
+
+  @Override
+  public HoverEvent.@NonNull ShowEntity deserializeShowEntity(@NonNull Component input,
+      Decoder<Component, String, ? extends RuntimeException> componentDecoder) throws IOException {
+    String snbt = PlainComponentSerializer.plain().serialize(input);
+    CompoundBinaryTag item = TagStringIO.get().asCompound(snbt);
+
+    Component name;
+    try {
+      name = componentDecoder.decode(item.getString("name"));
+    } catch (Exception e) {
+      name = TextComponent.of(item.getString("name"));
+    }
+
+    return new ShowEntity(Key.of(item.getString("type")),
+        UUID.fromString(item.getString("id")),
+        name);
+  }
+
+  @Override
+  public @NonNull Component serializeShowItem(HoverEvent.@NonNull ShowItem input)
+      throws IOException {
+    final CompoundBinaryTag.Builder builder = CompoundBinaryTag.builder()
+        .putByte("Count", (byte) input.count());
+
+    String keyAsString = input.item().asString();
+    if (keyAsString.startsWith("velocity:legacy_hover/id_")) {
+      builder.putByte("id", Byte.parseByte(keyAsString
+          .substring("velocity:legacy_hover/id_".length())));
+    } else {
+      builder.putString("id", keyAsString);
+    }
+    if (input.nbt() != null) {
+      builder.put("tag", TagStringIO.get().asCompound(input.nbt().string()));
+    }
+
+    return TextComponent.of(TagStringIO.get().asString(builder.build()));
+  }
+
+  @Override
+  public @NonNull Component serializeShowEntity(HoverEvent.@NonNull ShowEntity input,
+      Encoder<Component, String, ? extends RuntimeException> componentEncoder) throws IOException {
+    CompoundBinaryTag.Builder tag = CompoundBinaryTag.builder()
+        .putString("id", input.id().toString())
+        .putString("type", input.type().asString());
+    if (input.name() != null) {
+      tag.putString("name", componentEncoder.encode(input.name()));
+    }
+    return TextComponent.of(TagStringIO.get().asString(tag.build()));
+  }
+}