Only allow one session per player

src/main/java/emu/nebula/game/GameContext.java

@@ -65,12 +65,12 @@ public class GameContext {
         while (it.hasNext()) {
             var session = it.next().getValue();
             
-            if (timeout > session.getLastActiveTime()) {
+            if (timeout > session.getLastActiveTime() || session.isRemove()) {
                 // Remove from session map
                 it.remove();
                 
                 // Clear player
-                session.clearPlayer(this);
+                session.clearPlayer();
             }
         }
     }

src/main/java/emu/nebula/game/player/Player.java

@@ -1,7 +1,5 @@
 package emu.nebula.game.player;
 
-import java.util.HashSet;
-import java.util.Set;
 import java.util.Stack;
 
 import dev.morphia.annotations.Entity;
@@ -44,7 +42,7 @@ public class Player implements GameDatabaseObject {
     @Indexed private String accountUid;
     
     private transient Account account;
-    private transient Set<GameSession> sessions;
+    private transient GameSession session;
     
     // Details
     private String name;
@@ -80,7 +78,6 @@ public class Player implements GameDatabaseObject {
     
     @Deprecated // Morphia only
     public Player() {
-        this.sessions = new HashSet<>();
         this.characters = new CharacterStorage(this);
         this.gachaManager = new GachaManager(this);
         
@@ -135,22 +132,17 @@ public class Player implements GameDatabaseObject {
         return this.account;
     }
     
-    public void addSession(GameSession session) {
-        synchronized (this.sessions) {
-            this.sessions.add(session);
+    public void setSession(GameSession session) {
+        if (this.session != null) {
+            this.session.clearPlayer();
         }
+        
+        this.session = session;
     }
     
-    public void removeSession(GameSession session) {
-        synchronized (this.sessions) {
-            this.sessions.remove(session);
-        }
-    }
-    
-    public boolean hasSessions() {
-        synchronized (this.sessions) {
-            return !this.sessions.isEmpty();
-        }
+    public void removeSession() {
+        this.session = null;
+        Nebula.getGameContext().getPlayerModule().removeFromCache(this);
     }
     
     public boolean getGender() {

src/main/java/emu/nebula/net/GameSession.java

@@ -7,7 +7,6 @@ import org.bouncycastle.crypto.params.ECPrivateKeyParameters;
 import org.bouncycastle.crypto.params.ECPublicKeyParameters;
 
 import emu.nebula.Nebula;
-import emu.nebula.game.GameContext;
 import emu.nebula.game.account.Account;
 import emu.nebula.game.account.AccountHelper;
 import emu.nebula.game.player.Player;
@@ -32,19 +31,24 @@ public class GameSession {
     private byte[] serverPrivateKey;
     private byte[] key;
     
-    //
+    // Session cleanup
+    private boolean remove;
     private long lastActiveTime;
     
     public GameSession() {
         this.updateLastActiveTime();
     }
     
-    public void setPlayer(Player player) {
-        this.player = player;
-        this.player.addSession(this);
+    public synchronized Player getPlayer() {
+        return this.player;
     }
     
-    public void clearPlayer(GameContext context) {
+    public synchronized void setPlayer(Player player) {
+        this.player = player;
+        this.player.setSession(this);
+    }
+    
+    public synchronized void clearPlayer() {
         // Sanity check
         if (this.player == null) {
             return;
@@ -55,15 +59,13 @@ public class GameSession {
         this.player = null;
         
         // Remove session from player
-        player.removeSession(this);
+        player.removeSession();
         
-        // Clean up from player module
-        if (!player.hasSessions()) {
-            context.getPlayerModule().removeFromCache(player);
-        }
+        // Set remove flag
+        this.remove = true;
     }
 
-    public boolean hasPlayer() {
+    public synchronized boolean hasPlayer() {
         return this.player != null;
     }