1 files changed, 75 insertions, 15 deletions
diff --git a/tools/cru-py/cru/_error.py b/tools/cru-py/cru/_error.py
index e4bf3d6..e53c787 100644
--- a/tools/cru-py/cru/_error.py
+++ b/tools/cru-py/cru/_error.py
@@ -1,29 +1,89 @@
-from typing import NoReturn
+from __future__ import annotations
+
+from typing import NoReturn, cast, overload
 
 
 class CruException(Exception):
     """Base exception class of all exceptions in cru."""
 
+    @overload
+    def __init__(
+        self,
+        message: None = None,
+        *args,
+        user_message: str,
+        **kwargs,
+    ): ...
 
-class CruUnreachableError(CruException):
-    """Raised when a code path is unreachable."""
+    @overload
+    def __init__(
+        self,
+        message: str,
+        *args,
+        user_message: str | None = None,
+        **kwargs,
+    ): ...
 
+    def __init__(
+        self,
+        message: str | None = None,
+        *args,
+        user_message: str | None = None,
+        **kwargs,
+    ):
+        if message is None:
+            message = user_message
 
-def cru_unreachable() -> NoReturn:
-    raise CruUnreachableError()
+        super().__init__(
+            message,
+            *args,
+            **kwargs,
+        )
+        self._message: str
+        self._message = cast(str, message)
+        self._user_message = user_message
 
+    @property
+    def message(self) -> str:
+        return self._message
 
-class CruInternalError(CruException):
-    """Raised when an internal logic error occurs."""
+    def get_user_message(self) -> str | None:
+        return self._user_message
 
+    def get_message(self, use_user: bool = True) -> str:
+        if use_user and self._user_message is not None:
+            return self._user_message
+        else:
+            return self._message
 
-class CruUserFriendlyException(CruException):
-    def __init__(
-        self, message: str, user_message: str | None = None, *args, **kwargs
-    ) -> None:
-        super().__init__(message, *args, **kwargs)
-        self._user_message = user_message or message
+    @property
+    def is_internal(self) -> bool:
+        return False
 
     @property
-    def user_message(self) -> str:
-        return self._user_message
+    def is_logic_error(self) -> bool:
+        return False
+
+
+class CruLogicError(CruException):
+    """Raised when a logic error occurs."""
+
+    @property
+    def is_logic_error(self) -> bool:
+        return True
+
+
+class CruInternalError(CruException):
+    """Raised when an internal error occurs."""
+
+    @property
+    def is_internal(self) -> bool:
+        return True
+
+
+class CruUnreachableError(CruInternalError):
+    """Raised when a code path is unreachable."""
+
+
+def cru_unreachable() -> NoReturn:
+    raise CruUnreachableError("Code should not reach here!")