# pylint: disable=too-few-public-methods

from sqlalchemy.orm import DeclarativeBase
from sqlalchemy.orm.exc import DetachedInstanceError


class ReprHelper:
    # pylint: disable=no-member

    def _repr(self, **kwargs) -> str:
        """
        Helper for __repr__

        https://stackoverflow.com/a/55749579/16484891

        CC BY-SA 4.0
        """
        field_strings = []
        at_least_one_attached_attribute = False
        for key, field in kwargs.items():
            try:
                field_strings.append(f"{key}={field!r}")
            except DetachedInstanceError:
                field_strings.append(f"{key}=DetachedInstanceError")
            else:
                at_least_one_attached_attribute = True
        if at_least_one_attached_attribute:
            return f"<{self.__class__.__name__}({','.join(field_strings)})>"
        return f"<{self.__class__.__name__} {id(self)}>"

    def __repr__(self):
        if isinstance(self, DeclarativeBase):
            return self._repr(
                **{c.key: getattr(self, c.key) for c in self.__table__.columns}
            )
        return super().__repr__()