Run Velocity server change logic on event loop

common/src/main/java/us/myles/ViaVersion/api/data/UserConnection.java

@@ -36,7 +36,6 @@ public class UserConnection {
     // Used for handling warnings (over time)
     private int secondsObserved = 0;
     private int warnings = 0;
-    private ReadWriteLock velocityLock = new ReentrantReadWriteLock();
 
     public UserConnection(Channel channel) {
         this.channel = channel;

velocity/src/main/java/us/myles/ViaVersion/velocity/handlers/VelocityDecodeHandler.java

@@ -35,7 +35,6 @@ public class VelocityDecodeHandler extends MessageToMessageDecoder<ByteBuf> {
                 if (info.handlePPS())
                     return;
             }
-            info.getVelocityLock().readLock().lock();
             if (info.isActive()) {
                 // Handle ID
                 int id = Type.VAR_INT.read(bytebuf);
@@ -58,13 +57,11 @@ public class VelocityDecodeHandler extends MessageToMessageDecoder<ByteBuf> {
                     bytebuf.clear();
                     // Release Packet, be free!
                     newPacket.release();
-                    info.getVelocityLock().readLock().unlock();
                     throw e;
                 }
             } else {
                 bytebuf.retain();
             }
-            info.getVelocityLock().readLock().unlock();
 
             out.add(bytebuf);
         }

velocity/src/main/java/us/myles/ViaVersion/velocity/handlers/VelocityServerHandler.java

@@ -25,7 +25,9 @@ import java.util.ArrayList;
 import java.util.Collection;
 import java.util.List;
 import java.util.UUID;
+import java.util.concurrent.CompletableFuture;
 import java.util.concurrent.Semaphore;
+import java.util.concurrent.TimeUnit;
 
 public class VelocityServerHandler {
     private static Method setProtocolVersion;
@@ -75,27 +77,20 @@ public class VelocityServerHandler {
 
     @Subscribe(order = PostOrder.LATE)
     public void connectedEvent(ServerConnectedEvent e) {
+        UserConnection user = Via.getManager().getConnection(e.getPlayer().getUniqueId());
+            CompletableFuture.runAsync(() -> {
                 try {
                     checkServerChange(e, Via.getManager().getConnection(e.getPlayer().getUniqueId()));
                 } catch (Exception e1) {
                     e1.printStackTrace();
                 }
+            }, user.getChannel().eventLoop()).join();
     }
 
     public void checkServerChange(ServerConnectedEvent e, UserConnection user) throws Exception {
         if (user == null) return;
         // Handle server/version change
         if (user.has(VelocityStorage.class)) {
-            // Wait all the scheduled packets be sent
-            Semaphore semaphore = new Semaphore(1);
-            semaphore.acquireUninterruptibly();
-            user.getChannel().eventLoop().submit((Runnable) semaphore::release);
-            semaphore.acquireUninterruptibly();
-            semaphore.release();
-
-            user.getVelocityLock().writeLock().lock();
-
-            try {
             VelocityStorage storage = user.get(VelocityStorage.class);
 
             if (e.getServer() != null) {
@@ -180,9 +175,6 @@ public class VelocityServerHandler {
                     setProtocolVersion.invoke(connection, version);
                 }
             }
-            } finally {
-                user.getVelocityLock().writeLock().unlock();
-            }
         }
     }
 }