from django.contrib.contenttypes.models import ContentType
from django.db.models import QuerySet

class ReviewableMixin:
    """Mixin for models that can have reviews."""

    def get_reviews(self) -> QuerySet:
        """Get reviews for this instance."""
        from reviews.models import Review
        ct = ContentType.objects.get_for_model(self.__class__)
        return Review.objects.filter(content_type=ct, object_id=self.pk)

    def add_review(self, review: 'Review') -> None:
        """Add a review to this instance."""
        from reviews.models import Review
        ct = ContentType.objects.get_for_model(self.__class__)
        review.content_type = ct
        review.object_id = self.pk
        review.save()