refactor(backend): handle user with wrong login method

chatbot-core/backend/app/routers/auth.py

@@ -9,6 +9,7 @@
 from app.settings.constants import Constants
 from app.utils.api.api_response import APIResponse
 from app.utils.api.api_response import BackendAPIResponse
+from app.utils.api.error_handler import ErrorCodesMappingNumber
 from app.utils.api.helpers import get_logger
 from app.utils.user.jwt import create_access_token
 
@@ -49,11 +50,12 @@ def get_oauth_access_token(code: str, db_session: Session = Depends(get_db_sessi
         if err:
             status_code, detail = err.kind
             raise HTTPException(status_code=status_code, detail=detail)
-
-    if not user.is_oauth:
+    elif not user.is_oauth:
+        # If the user already exists with a different login method, return an error
+        status_code, detail = ErrorCodesMappingNumber.USER_WRONG_LOGIN_METHOD.value
         raise HTTPException(
-            status_code=status.HTTP_405_METHOD_NOT_ALLOWED,
-            detail=Constants.USER_WRONG_LOGIN_METHOD,
+            status_code=status_code,
+            detail=detail,
         )
 
     access_token = create_access_token(data=user_oauth_data.get("email"))

chatbot-core/backend/app/settings/constants.py

@@ -26,7 +26,6 @@ class Constants:
     FORBIDDEN_REQUEST_MESSAGE = "Forbidden request"
     NOT_FOUND_MESSAGE = "Not found"
     USER_NOT_FOUND_MESSAGE = "User not found"
-    USER_WRONG_LOGIN_METHOD = "Wrong login method"
     INTERNAL_SERVER_ERROR_MESSAGE = "Internal server error"
     EMPTY_CHAT_MESSAGE_MESSAGE = "Empty chat message"
 

chatbot-core/backend/app/utils/api/error_handler.py

@@ -24,6 +24,8 @@ class ErrorCodesMappingNumber(Enum):
     EMBEDDING_PROVIDER_NOT_FOUND = (422, "Embedding provider not found")
     PROVIDER_TYPE_CHANGE_NOT_ALLOWED = (422, "Provider type change not allowed")
 
+    USER_WRONG_LOGIN_METHOD = (405, "User already exists with wrong login method")
+
 
 class BaseException(Exception):
     """