Add a new loginstatus for CANCELLED_BY_USER_BEFORE_COMPLETE

api/src/main/java/com/velocitypowered/api/event/connection/DisconnectEvent.java

@@ -58,6 +58,7 @@ public final class DisconnectEvent {
     SUCCESSFUL_LOGIN,
     CONFLICTING_LOGIN,
     CANCELLED_BY_USER,
-    CANCELLED_BY_PROXY
+    CANCELLED_BY_PROXY,
+    CANCELLED_BY_USER_BEFORE_COMPLETE
   }
 }

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

@@ -8,6 +8,8 @@ import static com.velocitypowered.proxy.util.EncryptionUtils.decryptRsa;
 import static com.velocitypowered.proxy.util.EncryptionUtils.generateServerId;
 
 import com.google.common.base.Preconditions;
+import com.velocitypowered.api.event.connection.DisconnectEvent;
+import com.velocitypowered.api.event.connection.DisconnectEvent.LoginStatus;
 import com.velocitypowered.api.event.connection.LoginEvent;
 import com.velocitypowered.api.event.connection.PostLoginEvent;
 import com.velocitypowered.api.event.connection.PreLoginEvent;
@@ -224,13 +226,13 @@ public class LoginSessionHandler implements MinecraftSessionHandler {
             if (!mcConnection.isClosed()) {
               // wait for permissions to load, then set the players permission function
               player.setPermissionFunction(event.createFunction(player));
-              finishLogin(player);
+              completeLoginProtocolPhaseAndInitialize(player);
             }
           }, mcConnection.eventLoop());
     });  
   }
 
-  private void finishLogin(ConnectedPlayer player) {
+  private void completeLoginProtocolPhaseAndInitialize(ConnectedPlayer player) {
     int threshold = server.getConfiguration().getCompressionThreshold();
     if (threshold >= 0 && mcConnection.getProtocolVersion().compareTo(MINECRAFT_1_8) >= 0) {
       mcConnection.write(new SetCompression(threshold));
@@ -253,6 +255,8 @@ public class LoginSessionHandler implements MinecraftSessionHandler {
         .thenAcceptAsync(event -> {
           if (mcConnection.isClosed()) {
             // The player was disconnected
+            server.getEventManager().fireAndForget(new DisconnectEvent(player,
+                LoginStatus.CANCELLED_BY_USER_BEFORE_COMPLETE));
             return;
           }