from django.core.exceptions import ValidationError as DjangoValidationError

from rest_framework.exceptions import ValidationError as DRFValidationError
from rest_framework.views import exception_handler as drf_exception_handler


def exception_handler(exc, context):
    """ Handle Django ValidationError as an accepted exception """

    if isinstance(exc, DjangoValidationError):
        if hasattr(exc, 'message_dict'):
            exc = DRFValidationError(detail={'error': exc.message_dict})
        elif hasattr(exc, 'message'):
            exc = DRFValidationError(detail={'error': exc.message})
        elif hasattr(exc, 'messages'):
            exc = DRFValidationError(detail={'error': exc.messages})

    return drf_exception_handler(exc, context)