Add Configuration State API

api/src/main/java/com/velocitypowered/api/event/player/configuration/PlayerEnterConfigurationEvent.java

@@ -0,0 +1,24 @@
+/*
+ * Copyright (C) 2024 Velocity Contributors
+ *
+ * The Velocity API is licensed under the terms of the MIT License. For more details,
+ * reference the LICENSE file in the api top-level directory.
+ */
+
+package com.velocitypowered.api.event.player.configuration;
+
+import com.velocitypowered.api.proxy.Player;
+import org.jetbrains.annotations.NotNull;
+
+// TODO: Protocol State API
+/**
+ * This event is executed when a player with version 1.20.2 or higher enters the configuration phase.
+ * <p>From this moment on, until the {@link PlayerFinishedConfigurationEvent} is executed,
+ * the {@linkplain Player#protocolState()} method is guaranteed
+ * to return {@link ProtocolState#CONFIGURATION}.</p>
+ *
+ * @param player The player that has entered the configuration phase
+ * @since 3.3.0
+ */
+public record PlayerEnterConfigurationEvent(@NotNull Player player) {
+}

api/src/main/java/com/velocitypowered/api/event/player/configuration/PlayerFinishConfigurationEvent.java

@@ -0,0 +1,23 @@
+/*
+ * Copyright (C) 2024 Velocity Contributors
+ *
+ * The Velocity API is licensed under the terms of the MIT License. For more details,
+ * reference the LICENSE file in the api top-level directory.
+ */
+
+package com.velocitypowered.api.event.player.configuration;
+
+import com.velocitypowered.api.event.annotation.AwaitingEvent;
+import com.velocitypowered.api.proxy.Player;
+import org.jetbrains.annotations.NotNull;
+
+// TODO: Protocol State API
+/**
+ * This event is executed when the player is about to finish the Configuration state.
+ * <p>Velocity will wait for this event to finish the configuration phase on the client.</p>
+ *
+ * @param player The player who is about to complete the configuration phase
+ */
+@AwaitingEvent
+public record PlayerFinishConfigurationEvent(@NotNull Player player) {
+}

api/src/main/java/com/velocitypowered/api/event/player/configuration/PlayerFinishedConfigurationEvent.java

@@ -0,0 +1,20 @@
+/*
+ * Copyright (C) 2024 Velocity Contributors
+ *
+ * The Velocity API is licensed under the terms of the MIT License. For more details,
+ * reference the LICENSE file in the api top-level directory.
+ */
+
+package com.velocitypowered.api.event.player.configuration;
+
+import com.velocitypowered.api.proxy.Player;
+
+/**
+ * Event executed when a player of version 1.20.2 finishes the Configuration state.
+ * <p>From this moment on, the {@link Player#protocolState()} method
+ * will return {@link ProtocolState#PLAY}.</p>
+ *
+ * @param player The player who has completed the Configuration state
+ */
+public record PlayerFinishedConfigurationEvent(Player player) {
+}

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

@@ -45,7 +45,7 @@
 import com.velocitypowered.proxy.command.builtin.VelocityCommand;
 import com.velocitypowered.proxy.config.VelocityConfiguration;
 import com.velocitypowered.proxy.connection.client.ConnectedPlayer;
-import com.velocitypowered.proxy.connection.player.VelocityResourcePackInfo;
+import com.velocitypowered.proxy.connection.player.resourcepack.VelocityResourcePackInfo;
 import com.velocitypowered.proxy.connection.util.ServerListPingHandler;
 import com.velocitypowered.proxy.console.VelocityConsole;
 import com.velocitypowered.proxy.crypto.EncryptionUtils;

proxy/src/main/java/com/velocitypowered/proxy/connection/MinecraftConnection.java

@@ -148,13 +148,11 @@ public void channelRead(ChannelHandlerContext ctx, Object msg) throws Exception
         return;
       }
 
-      if (msg instanceof MinecraftPacket) {
-        MinecraftPacket pkt = (MinecraftPacket) msg;
+      if (msg instanceof MinecraftPacket pkt) {
         if (!pkt.handle(activeSessionHandler)) {
           activeSessionHandler.handleGeneric((MinecraftPacket) msg);
         }
-      } else if (msg instanceof HAProxyMessage) {
-        HAProxyMessage proxyMessage = (HAProxyMessage) msg;
+      } else if (msg instanceof HAProxyMessage proxyMessage) {
         this.remoteAddress = new InetSocketAddress(proxyMessage.sourceAddress(),
             proxyMessage.sourcePort());
       } else if (msg instanceof ByteBuf) {

proxy/src/main/java/com/velocitypowered/proxy/connection/backend/BackendPlaySessionHandler.java

@@ -37,8 +37,8 @@
 import com.velocitypowered.proxy.connection.MinecraftSessionHandler;
 import com.velocitypowered.proxy.connection.client.ClientPlaySessionHandler;
 import com.velocitypowered.proxy.connection.client.ConnectedPlayer;
-import com.velocitypowered.proxy.connection.player.VelocityResourcePackInfo;
-import com.velocitypowered.proxy.connection.player.resourcepack.ResourcePackHandler;
+import com.velocitypowered.proxy.connection.player.resourcepack.VelocityResourcePackInfo;
+import com.velocitypowered.proxy.connection.player.resourcepack.handler.ResourcePackHandler;
 import com.velocitypowered.proxy.connection.util.ConnectionMessages;
 import com.velocitypowered.proxy.protocol.MinecraftPacket;
 import com.velocitypowered.proxy.protocol.StateRegistry;

proxy/src/main/java/com/velocitypowered/proxy/connection/backend/BungeeCordMessageResponder.java

@@ -37,7 +37,6 @@
 import io.netty.buffer.Unpooled;
 import java.util.Optional;
 import java.util.StringJoiner;
-import net.kyori.adventure.identity.Identity;
 import net.kyori.adventure.text.Component;
 import net.kyori.adventure.text.serializer.ComponentSerializer;
 import net.kyori.adventure.text.serializer.gson.GsonComponentSerializer;
@@ -143,7 +142,7 @@ private void processPlayerList(ByteBufDataInput in) {
         out.writeUTF("PlayerList");
         out.writeUTF(info.getServerInfo().getName());
 
-        StringJoiner joiner = new StringJoiner(", ");
+        final StringJoiner joiner = new StringJoiner(", ");
         for (Player online : info.getPlayersConnected()) {
           joiner.add(online.getUsername());
         }
@@ -187,10 +186,9 @@ private void processMessage0(ByteBufDataInput in,
 
     Component messageComponent = serializer.deserialize(message);
     if (target.equals("ALL")) {
-      proxy.sendMessage(Identity.nil(), messageComponent);
+      proxy.sendMessage(messageComponent);
     } else {
-      proxy.getPlayer(target).ifPresent(player -> player.sendMessage(Identity.nil(),
-          messageComponent));
+      proxy.getPlayer(target).ifPresent(player -> player.sendMessage(messageComponent));
     }
   }
 

proxy/src/main/java/com/velocitypowered/proxy/connection/backend/ConfigSessionHandler.java

@@ -26,7 +26,7 @@
 import com.velocitypowered.proxy.connection.MinecraftSessionHandler;
 import com.velocitypowered.proxy.connection.client.ClientConfigSessionHandler;
 import com.velocitypowered.proxy.connection.client.ConnectedPlayer;
-import com.velocitypowered.proxy.connection.player.VelocityResourcePackInfo;
+import com.velocitypowered.proxy.connection.player.resourcepack.VelocityResourcePackInfo;
 import com.velocitypowered.proxy.connection.util.ConnectionMessages;
 import com.velocitypowered.proxy.connection.util.ConnectionRequestResults;
 import com.velocitypowered.proxy.connection.util.ConnectionRequestResults.Impl;
@@ -171,15 +171,16 @@ public boolean handle(final ResourcePackRequestPacket packet) {
 
   @Override
   public boolean handle(FinishedUpdatePacket packet) {
-    MinecraftConnection smc = serverConn.ensureConnected();
-    ConnectedPlayer player = serverConn.getPlayer();
-    ClientConfigSessionHandler configHandler =
+    final MinecraftConnection smc = serverConn.ensureConnected();
+    final ConnectedPlayer player = serverConn.getPlayer();
+    final ClientConfigSessionHandler configHandler =
         (ClientConfigSessionHandler) player.getConnection().getActiveSessionHandler();
 
     smc.setAutoReading(false);
     // Even when not auto reading messages are still decoded. Decode them with the correct state
     smc.getChannel().pipeline().get(MinecraftDecoder.class).setState(StateRegistry.PLAY);
-    configHandler.handleBackendFinishUpdate(serverConn).thenAcceptAsync((unused) -> {
+    //noinspection DataFlowIssue
+    configHandler.handleBackendFinishUpdate(serverConn).thenRunAsync(() -> {
       if (serverConn == player.getConnectedServer()) {
         smc.setActiveSessionHandler(StateRegistry.PLAY);
         player.sendPlayerListHeaderAndFooter(

proxy/src/main/java/com/velocitypowered/proxy/connection/backend/LoginSessionHandler.java

@@ -162,12 +162,9 @@ public boolean handle(ServerLoginSuccessPacket packet) {
       if (player.getClientSettingsPacket() != null) {
         smc.write(player.getClientSettingsPacket());
       }
-      if (player.getConnection().getActiveSessionHandler() instanceof ClientPlaySessionHandler) {
+      if (player.getConnection().getActiveSessionHandler() instanceof ClientPlaySessionHandler clientPlaySessionHandler) {
         smc.setAutoReading(false);
-        ((ClientPlaySessionHandler) player.getConnection()
-            .getActiveSessionHandler()).doSwitch().thenAcceptAsync((unused) -> {
-              smc.setAutoReading(true);
-            }, smc.eventLoop());
+        clientPlaySessionHandler.doSwitch().thenAcceptAsync((unused) -> smc.setAutoReading(true), smc.eventLoop());
       }
     }
 

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

@@ -18,6 +18,8 @@
 package com.velocitypowered.proxy.connection.client;
 
 import com.velocitypowered.api.event.player.PlayerClientBrandEvent;
+import com.velocitypowered.api.event.player.configuration.PlayerFinishConfigurationEvent;
+import com.velocitypowered.api.event.player.configuration.PlayerFinishedConfigurationEvent;
 import com.velocitypowered.proxy.VelocityServer;
 import com.velocitypowered.proxy.connection.MinecraftConnection;
 import com.velocitypowered.proxy.connection.MinecraftSessionHandler;
@@ -208,10 +210,13 @@ public CompletableFuture<Void> handleBackendFinishUpdate(VelocityServerConnectio
       smc.write(brandPacket);
     }
 
-    player.getConnection().eventLoop().execute(() -> {
-      player.getConnection().write(FinishedUpdatePacket.INSTANCE);
-      player.getConnection().getChannel().pipeline().get(MinecraftEncoder.class).setState(StateRegistry.PLAY);
-    });
+    server.getEventManager().fire(new PlayerFinishConfigurationEvent(player))
+        .thenAcceptAsync(event -> {
+          player.getConnection().write(FinishedUpdatePacket.INSTANCE);
+          player.getConnection().getChannel().pipeline()
+                  .get(MinecraftEncoder.class).setState(StateRegistry.PLAY);
+          server.getEventManager().fireAndForget(new PlayerFinishedConfigurationEvent(player));
+        }, player.getConnection().eventLoop());
 
     smc.write(FinishedUpdatePacket.INSTANCE);
     smc.getChannel().pipeline().get(MinecraftEncoder.class).setState(StateRegistry.PLAY);

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

@@ -26,6 +26,7 @@
 import com.velocitypowered.api.event.player.PlayerChannelRegisterEvent;
 import com.velocitypowered.api.event.player.PlayerClientBrandEvent;
 import com.velocitypowered.api.event.player.TabCompleteEvent;
+import com.velocitypowered.api.event.player.configuration.PlayerEnterConfigurationEvent;
 import com.velocitypowered.api.network.ProtocolVersion;
 import com.velocitypowered.api.proxy.messages.ChannelIdentifier;
 import com.velocitypowered.api.proxy.messages.LegacyChannelIdentifier;
@@ -402,6 +403,7 @@ public boolean handle(ResourcePackResponsePacket packet) {
   public boolean handle(FinishedUpdatePacket packet) {
     // Complete client switch
     player.getConnection().setActiveSessionHandler(StateRegistry.CONFIG);
+    server.getEventManager().fireAndForget(new PlayerEnterConfigurationEvent(player));
     VelocityServerConnection serverConnection = player.getConnectedServer();
     if (serverConnection != null) {
       MinecraftConnection smc = serverConnection.ensureConnected();
@@ -487,7 +489,7 @@ public void writabilityChanged() {
    * @return a future that completes when the switch is complete
    */
   public CompletableFuture<Void> doSwitch() {
-    VelocityServerConnection existingConnection = player.getConnectedServer();
+    final VelocityServerConnection existingConnection = player.getConnectedServer();
 
     if (existingConnection != null) {
       // Shut down the existing server connection.

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

@@ -34,6 +34,7 @@
 import com.velocitypowered.api.event.player.PlayerModInfoEvent;
 import com.velocitypowered.api.event.player.PlayerSettingsChangedEvent;
 import com.velocitypowered.api.event.player.ServerPreConnectEvent;
+import com.velocitypowered.api.event.player.configuration.PlayerEnterConfigurationEvent;
 import com.velocitypowered.api.network.ProtocolState;
 import com.velocitypowered.api.network.ProtocolVersion;
 import com.velocitypowered.api.permission.PermissionFunction;
@@ -56,8 +57,9 @@
 import com.velocitypowered.proxy.connection.MinecraftConnection;
 import com.velocitypowered.proxy.connection.MinecraftConnectionAssociation;
 import com.velocitypowered.proxy.connection.backend.VelocityServerConnection;
-import com.velocitypowered.proxy.connection.player.VelocityResourcePackInfo;
-import com.velocitypowered.proxy.connection.player.resourcepack.ResourcePackHandler;
+import com.velocitypowered.proxy.connection.player.bundle.BundleDelimiterHandler;
+import com.velocitypowered.proxy.connection.player.resourcepack.VelocityResourcePackInfo;
+import com.velocitypowered.proxy.connection.player.resourcepack.handler.ResourcePackHandler;
 import com.velocitypowered.proxy.connection.util.ConnectionMessages;
 import com.velocitypowered.proxy.connection.util.ConnectionRequestResults.Impl;
 import com.velocitypowered.proxy.connection.util.VelocityInboundConnection;
@@ -799,7 +801,7 @@ private void handleKickEvent(KickedFromServerEvent originalEvent, Component frie
             }, connection.eventLoop());
       } else if (event.getResult() instanceof final Notify res) {
         if (event.kickedDuringServerConnect() && previousConnection != null) {
-          sendMessage(Identity.nil(), res.getMessageComponent());
+          sendMessage(res.getMessageComponent());
         } else {
           disconnect(res.getMessageComponent());
         }
@@ -1154,11 +1156,12 @@ public void switchToConfigState() {
     CompletableFuture.runAsync(() -> {
       connection.write(StartUpdatePacket.INSTANCE);
       connection.getChannel().pipeline()
-          .get(MinecraftEncoder.class).setState(StateRegistry.CONFIG);
+              .get(MinecraftEncoder.class).setState(StateRegistry.CONFIG);
       // Make sure we don't send any play packets to the player after update start
       connection.addPlayPacketQueueHandler();
+      server.getEventManager().fireAndForget(new PlayerEnterConfigurationEvent(this));
     }, connection.eventLoop()).exceptionally((ex) -> {
-      logger.error("Error switching player connection to config state:", ex);
+      logger.error("Error switching player connection to config state", ex);
       return null;
     });
   }
@@ -1293,24 +1296,20 @@ public CompletableFuture<Boolean> connectWithIndication() {
         }
 
         switch (status.getStatus()) {
-          case ALREADY_CONNECTED:
-            sendMessage(Identity.nil(), ConnectionMessages.ALREADY_CONNECTED);
-            break;
-          case CONNECTION_IN_PROGRESS:
-            sendMessage(Identity.nil(), ConnectionMessages.IN_PROGRESS);
-            break;
-          case CONNECTION_CANCELLED:
+          case ALREADY_CONNECTED -> sendMessage(ConnectionMessages.ALREADY_CONNECTED);
+          case CONNECTION_IN_PROGRESS -> sendMessage(ConnectionMessages.IN_PROGRESS);
+          case CONNECTION_CANCELLED -> {
             // Ignored; the plugin probably already handled this.
-            break;
-          case SERVER_DISCONNECTED:
-            Component reason = status.getReasonComponent()
-                .orElse(ConnectionMessages.INTERNAL_SERVER_CONNECTION_ERROR);
+          }
+          case SERVER_DISCONNECTED -> {
+            final Component reason = status.getReasonComponent()
+                    .orElse(ConnectionMessages.INTERNAL_SERVER_CONNECTION_ERROR);
             handleConnectionException(toConnect,
-                DisconnectPacket.create(reason, getProtocolVersion(), connection.getState()), status.isSafe());
-            break;
-          default:
+                    DisconnectPacket.create(reason, getProtocolVersion(), connection.getState()), status.isSafe());
+          }
+          default -> {
             // The only remaining value is successful (no need to do anything!)
-            break;
+          }
         }
       }, connection.eventLoop()).thenApply(Result::isSuccessful);
     }

proxy/src/main/java/com/velocitypowered/proxy/connection/client/BundleDelimiterHandler.java → proxy/src/main/java/com/velocitypowered/proxy/connection/player/bundle/BundleDelimiterHandler.java

@@ -15,10 +15,11 @@
  * along with this program.  If not, see <https://www.gnu.org/licenses/>.
  */
 
-package com.velocitypowered.proxy.connection.client;
+package com.velocitypowered.proxy.connection.player.bundle;
 
 import com.velocitypowered.proxy.connection.MinecraftConnection;
 import com.velocitypowered.proxy.connection.backend.VelocityServerConnection;
+import com.velocitypowered.proxy.connection.client.ConnectedPlayer;
 import com.velocitypowered.proxy.protocol.StateRegistry;
 import com.velocitypowered.proxy.protocol.packet.BundleDelimiterPacket;
 import java.util.concurrent.CompletableFuture;

proxy/src/main/java/com/velocitypowered/proxy/connection/player/VelocityResourcePackInfo.java → proxy/src/main/java/com/velocitypowered/proxy/connection/player/resourcepack/VelocityResourcePackInfo.java

@@ -15,7 +15,7 @@
  * along with this program.  If not, see <https://www.gnu.org/licenses/>.
  */
 
-package com.velocitypowered.proxy.connection.player;
+package com.velocitypowered.proxy.connection.player.resourcepack;
 
 import com.google.common.base.Preconditions;
 import com.velocitypowered.api.proxy.player.ResourcePackInfo;

proxy/src/main/java/com/velocitypowered/proxy/connection/player/resourcepack/Legacy117ResourcePackHandler.java → proxy/src/main/java/com/velocitypowered/proxy/connection/player/resourcepack/handler/Legacy117ResourcePackHandler.java

@@ -15,7 +15,7 @@
  * along with this program.  If not, see <https://www.gnu.org/licenses/>.
  */
 
-package com.velocitypowered.proxy.connection.player.resourcepack;
+package com.velocitypowered.proxy.connection.player.resourcepack.handler;
 
 import com.velocitypowered.api.event.player.PlayerResourcePackStatusEvent;
 import com.velocitypowered.proxy.VelocityServer;

proxy/src/main/java/com/velocitypowered/proxy/connection/player/resourcepack/LegacyResourcePackHandler.java → proxy/src/main/java/com/velocitypowered/proxy/connection/player/resourcepack/handler/LegacyResourcePackHandler.java

@@ -15,13 +15,14 @@
  * along with this program.  If not, see <https://www.gnu.org/licenses/>.
  */
 
-package com.velocitypowered.proxy.connection.player.resourcepack;
+package com.velocitypowered.proxy.connection.player.resourcepack.handler;
 
 import com.velocitypowered.api.event.player.PlayerResourcePackStatusEvent;
 import com.velocitypowered.api.network.ProtocolVersion;
 import com.velocitypowered.api.proxy.player.ResourcePackInfo;
 import com.velocitypowered.proxy.VelocityServer;
 import com.velocitypowered.proxy.connection.client.ConnectedPlayer;
+import com.velocitypowered.proxy.connection.player.resourcepack.ResourcePackResponseBundle;
 import java.util.ArrayDeque;
 import java.util.Arrays;
 import java.util.Collection;
@@ -109,7 +110,7 @@ private void tickResourcePackQueue() {
             break;
           }
           onResourcePackResponse(new ResourcePackResponseBundle(queued.getId(),
-                  new String(queued.getHash()),
+                  queued.getHash() == null ? null : new String(queued.getHash()),
                   PlayerResourcePackStatusEvent.Status.DECLINED));
           queued = null;
         }

proxy/src/main/java/com/velocitypowered/proxy/connection/player/resourcepack/ModernResourcePackHandler.java → proxy/src/main/java/com/velocitypowered/proxy/connection/player/resourcepack/handler/ModernResourcePackHandler.java

@@ -15,14 +15,15 @@
  * along with this program.  If not, see <https://www.gnu.org/licenses/>.
  */
 
-package com.velocitypowered.proxy.connection.player.resourcepack;
+package com.velocitypowered.proxy.connection.player.resourcepack.handler;
 
 import com.google.common.collect.ListMultimap;
 import com.google.common.collect.Multimaps;
 import com.velocitypowered.api.event.player.PlayerResourcePackStatusEvent;
 import com.velocitypowered.api.proxy.player.ResourcePackInfo;
 import com.velocitypowered.proxy.VelocityServer;
 import com.velocitypowered.proxy.connection.client.ConnectedPlayer;
+import com.velocitypowered.proxy.connection.player.resourcepack.ResourcePackResponseBundle;
 import java.util.Arrays;
 import java.util.Collection;
 import java.util.LinkedList;