class AppException(Exception):
    def __init__(self, status_code: int = 500, code: str = "INTERNAL_ERROR", detail: str = "An error occurred"):
        self.status_code = status_code
        self.code = code
        self.detail = detail


class NotFoundException(AppException):
    def __init__(self, detail: str = "Resource not found"):
        super().__init__(status_code=404, code="NOT_FOUND", detail=detail)


class ForbiddenException(AppException):
    def __init__(self, detail: str = "Access denied"):
        super().__init__(status_code=403, code="FORBIDDEN", detail=detail)


class ValidationException(AppException):
    def __init__(self, detail: str = "Validation error"):
        super().__init__(status_code=422, code="VALIDATION_ERROR", detail=detail)


class RateLimitException(AppException):
    def __init__(self, detail: str = "Too many requests"):
        super().__init__(status_code=429, code="RATE_LIMIT_EXCEEDED", detail=detail)