♻️ 리뷰내용 반영

Author: sehee123

backend/src/main/java/io/f1/backend/domain/game/app/RoomService.java

@@ -271,7 +271,7 @@ public void chat(Long roomId, String sessionId, ChatMessage chatMessage) {
 
     public boolean isReconnectTarget(Long roomId, String sessionId) {
         Room room = findRoom(roomId);
-        return room.isReconnectTarget(sessionId);
+        return !room.isExit(sessionId);
     }
 
     public void reconnectSession(Long roomId, String oldSessionId, String newSessionId) {

backend/src/main/java/io/f1/backend/domain/game/model/Room.java

@@ -126,10 +126,6 @@ public void updatePlayerConnectionState(String sessionId, ConnectionState newSta
         playerSessionMap.get(sessionId).updateState(newState);
     }
 
-    public boolean isReconnectTarget(String sessionId) {
-        return playerSessionMap.get(sessionId) != null;
-    }
-
     public boolean isExit(String sessionId) {
         return playerSessionMap.get(sessionId) == null;
     }

backend/src/main/java/io/f1/backend/domain/game/websocket/Service/SessionService.java

@@ -49,14 +49,14 @@ public void handleUserReconnect(Long roomId, String newSessionId, Long userId) {
     public void handleUserDisconnect(String sessionId, UserPrincipal principal) {
 
         Long roomId = sessionIdRoom.get(sessionId);
+        Long userId = sessionIdUser.get(sessionId);
 
         /* 정상 동작*/
         if (roomService.isExit(sessionId, roomId)) {
-            removeSession(sessionId, roomId);
+            removeSession(sessionId, userId);
             return;
         }
 
-        Long userId = principal.getUserId();
 
         roomService.changeConnectedStatus(roomId, sessionId, ConnectionState.DISCONNECTED);
 
@@ -69,7 +69,7 @@ public void handleUserDisconnect(String sessionId, UserPrincipal principal) {
                         roomService.notifyIfReconnected(roomId, principal);
                     }
                     userIdLatestSession.remove(principal.getUserId());
-                    removeSession(sessionId, roomId);
+                    removeSession(sessionId, userId);
                 },
                 5,
                 TimeUnit.SECONDS);

backend/src/main/java/io/f1/backend/global/util/SecurityUtils.java

@@ -33,7 +33,7 @@ public static UserPrincipal getCurrentUserPrincipal() {
                 && authentication.getPrincipal() instanceof UserPrincipal userPrincipal) {
             return userPrincipal;
         }
-        throw new RuntimeException("E401001: 로그인이 필요합니다.");
+        throw new CustomException(AuthErrorCode.UNAUTHORIZED);
     }
 
     public static Long getCurrentUserId() {