Added: LatencyTracker - Credits to Mike

Emulator/.idea/misc.xml

@@ -8,5 +8,5 @@
       </list>
     </option>
   </component>
-  <component name="ProjectRootManager" version="2" project-jdk-name="openjdk-21" project-jdk-type="JavaSDK" />
+  <component name="ProjectRootManager" version="2" languageLevel="JDK_X" default="true" project-jdk-name="19" project-jdk-type="JavaSDK" />
 </project>

Emulator/src/main/java/com/eu/habbo/habbohotel/LatencyTracker.java

@@ -0,0 +1,47 @@
+package com.eu.habbo.habbohotel;
+
+import com.eu.habbo.habbohotel.gameclients.GameClient;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import java.util.concurrent.TimeUnit;
+
+public class LatencyTracker {
+
+    private static final Logger LOGGER = LoggerFactory.getLogger(GameClient.class);
+
+    private boolean initialPing;
+
+    private long last;
+    private long average;
+
+    public LatencyTracker() {
+        this.initialPing = true;
+        this.average = 0;
+    }
+
+    public void update(long latencyInNano) {
+        this.last = latencyInNano;
+
+        if (this.initialPing) {
+            this.initialPing = false;
+            this.average = latencyInNano;
+            return;
+        }
+
+        this.average = (long) (this.average * .7f + latencyInNano * .3f);
+    }
+
+    public boolean hasInitialized() {
+        return !this.initialPing;
+    }
+
+    public long getLastMs() {
+        return TimeUnit.NANOSECONDS.toMillis(this.last);
+    }
+
+    public long getAverageMs() {
+        return TimeUnit.NANOSECONDS.toMillis(this.average);
+    }
+
+}

Emulator/src/main/java/com/eu/habbo/habbohotel/commands/CommandHandler.java

@@ -230,6 +230,7 @@ public class CommandHandler {
         addCommand(new MutePetsCommand());
         addCommand(new PetInfoCommand());
         addCommand(new PickallCommand());
+        addCommand(new PingCommand());
         addCommand(new PixelCommand());
         addCommand(new PluginsCommand());
         addCommand(new PointsCommand());

Emulator/src/main/java/com/eu/habbo/habbohotel/commands/PingCommand.java

@@ -0,0 +1,29 @@
+package com.eu.habbo.habbohotel.commands;
+
+import com.eu.habbo.habbohotel.LatencyTracker;
+import com.eu.habbo.habbohotel.gameclients.GameClient;
+
+public class PingCommand extends Command {
+    public PingCommand() {
+        super(null, new String[]{"ping"});
+    }
+
+    @Override
+    public boolean handle(GameClient gameClient, String[] params) throws Exception {
+        if (gameClient.getHabbo().getRoomUnit() == null) {
+            return true;
+        }
+
+        final LatencyTracker latencyTracker = gameClient.getLatencyTracker();
+
+        if (latencyTracker.hasInitialized()) {
+            gameClient.getHabbo().whisper(String.format("Average ping %dms, last ping %dms",
+                    latencyTracker.getAverageMs(),
+                    latencyTracker.getLastMs()));
+        } else {
+            gameClient.getHabbo().whisper("\n" + "Ping speed has not been calculated yet, please try again in a minute.");
+        }
+
+        return true;
+    }
+}

Emulator/src/main/java/com/eu/habbo/habbohotel/gameclients/GameClient.java

@@ -2,6 +2,7 @@ package com.eu.habbo.habbohotel.gameclients;
 
 import com.eu.habbo.Emulator;
 import com.eu.habbo.crypto.HabboEncryption;
+import com.eu.habbo.habbohotel.LatencyTracker;
 import com.eu.habbo.habbohotel.users.Habbo;
 import com.eu.habbo.messages.ServerMessage;
 import com.eu.habbo.messages.incoming.MessageHandler;
@@ -10,9 +11,6 @@ import io.netty.channel.Channel;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
-import java.sql.Connection;
-import java.sql.PreparedStatement;
-import java.sql.SQLException;
 import java.util.ArrayList;
 import java.util.concurrent.ConcurrentHashMap;
 
@@ -22,7 +20,7 @@ public class GameClient {
 
     private final Channel channel;
     private final HabboEncryption encryption;
-
+    private final LatencyTracker latencyTracker;
     private Habbo habbo;
     private boolean handshakeFinished;
     private String machineId = "";
@@ -39,6 +37,7 @@ public class GameClient {
                     Emulator.getCrypto().getModulus(),
                     Emulator.getCrypto().getPrivateExponent())
                 : null;
+        this.latencyTracker = new LatencyTracker();
     }
 
     public Channel getChannel() {
@@ -49,6 +48,8 @@ public class GameClient {
         return encryption;
     }
 
+    public LatencyTracker getLatencyTracker() { return latencyTracker; }
+
     public Habbo getHabbo() {
         return this.habbo;
     }

Emulator/src/main/java/com/eu/habbo/networking/gameserver/handlers/IdleTimeoutHandler.java

@@ -18,7 +18,9 @@ public class IdleTimeoutHandler extends ChannelDuplexHandler {
     private final long pongTimeoutNanos;
 
     volatile ScheduledFuture<?> pingScheduleFuture;
-    volatile long lastPongTime;// in nanoseconds
+    volatile boolean sentPing;
+    volatile long lastPingTime; // in nanoseconds
+    volatile long lastPongTime; // in nanoseconds
 
     private volatile int state; // 0 - none, 1 - initialized, 2 - destroyed
 
@@ -97,10 +99,18 @@ public class IdleTimeoutHandler extends ChannelDuplexHandler {
     @Override
     public void channelRead(ChannelHandlerContext ctx, Object msg) throws Exception {
         // check if its a pong message
-        if(msg instanceof ClientMessage) {
+        if (msg instanceof ClientMessage) {
             ClientMessage packet = (ClientMessage) msg;
-            if(packet.getMessageId() == Incoming.PongEvent) {
+            if (packet.getMessageId() == Incoming.PongEvent) {
                 this.lastPongTime = System.nanoTime();
+
+                final GameClient client = ctx.channel().attr(GameServerAttributes.CLIENT).get();
+                if (client != null) {
+                    if (sentPing) {
+                        sentPing = false;
+                        client.getLatencyTracker().update(lastPongTime - lastPingTime);
+                    }
+                }
             }
         }
         super.channelRead(ctx, msg);
@@ -120,13 +130,15 @@ public class IdleTimeoutHandler extends ChannelDuplexHandler {
             }
 
             long currentTime = System.nanoTime();
-            if(currentTime - lastPongTime > pongTimeoutNanos) {
+            if (currentTime - lastPongTime > pongTimeoutNanos) {
                 ctx.close();// add a promise here ?
                 return;
             }
 
-            GameClient client = ctx.channel().attr(GameServerAttributes.CLIENT).get();
+            final GameClient client = ctx.channel().attr(GameServerAttributes.CLIENT).get();
             if (client != null) {
+                lastPingTime = System.nanoTime();
+                sentPing = true;
                 client.sendResponse(new PingComposer());
             }