Implement hiding and showing functionality for user exams and collections

generic/models.py

@@ -698,6 +698,12 @@ class ExamOrCollectionGenericBase(models.Model, AuthorMixin):
         default=True,
     )
 
+    @property
+    def content_type_id(self) -> int:
+        from django.contrib.contenttypes.models import ContentType
+        return ContentType.objects.get_for_model(self).id
+
+
     authors_only = models.BooleanField(
         help_text="If true only exam/collection authors will be able to view.",
         default=False,
@@ -2390,3 +2396,28 @@ class FindingBase(models.Model):
             return get_pretty_json(json.loads(self.viewport_json))
         except Exception:
             return ""
+
+class UserHiddenItem(models.Model):
+    """Model to track which exams or collections have been hidden by a user.
+    """
+    user = models.ForeignKey(
+        settings.AUTH_USER_MODEL,
+        on_delete=models.CASCADE,
+        related_name="hidden_items",
+    )
+    content_type = models.ForeignKey(ContentType, on_delete=models.CASCADE)
+    object_id = models.PositiveIntegerField()
+    content_object = GenericForeignKey("content_type", "object_id")
+    created_at = models.DateTimeField(auto_now_add=True)
+
+    class Meta:
+        constraints = [
+            models.UniqueConstraint(
+                fields=["user", "content_type", "object_id"],
+                name="unique_user_hidden_item",
+            )
+        ]
+
+    def __str__(self):
+        return f"{self.user} hid {self.content_object}"
+