Refactor comments app to use mixins for comment functionality; update admin interfaces and add historical model fixes

comments/models.py

@@ -2,20 +2,17 @@ from django.db import models
 from django.conf import settings
 from django.contrib.contenttypes.fields import GenericForeignKey
 from django.contrib.contenttypes.models import ContentType
+from .managers import CommentThreadManager, ThreadedModelManager
 
 class CommentThread(models.Model):
     """
-    A generic comment thread that can be attached to any model instance.
-    Used for tracking discussions on various objects across the platform.
+    A thread of comments that can be attached to any model instance,
+    including historical versions.
     """
-    content_type = models.ForeignKey(
-        ContentType,
-        on_delete=models.CASCADE,
-        related_name='comment_threads'
-    )
+    content_type = models.ForeignKey(ContentType, on_delete=models.CASCADE)
     object_id = models.PositiveIntegerField()
     content_object = GenericForeignKey('content_type', 'object_id')
-
+    
     title = models.CharField(max_length=255, blank=True)
     created_at = models.DateTimeField(auto_now_add=True)
     updated_at = models.DateTimeField(auto_now=True)
@@ -28,6 +25,8 @@ class CommentThread(models.Model):
     is_locked = models.BooleanField(default=False)
     is_hidden = models.BooleanField(default=False)
 
+    objects = CommentThreadManager()
+
     class Meta:
         indexes = [
             models.Index(fields=['content_type', 'object_id']),
@@ -37,11 +36,57 @@ class CommentThread(models.Model):
     def __str__(self):
         return f"Comment Thread on {self.content_object} - {self.title}"
 
+class CommentThreads:
+    """
+    Helper class to manage comment threads for a model instance.
+    This is used instead of direct inheritance to avoid historical model issues.
+    """
+    def __init__(self, instance):
+        self.instance = instance
+        self._info = {}
+
+    def get_info(self):
+        """Get or compute comment thread information."""
+        if not self._info:
+            ct = ContentType.objects.get_for_model(self.instance.__class__)
+            self._info = {
+                'count': CommentThread.objects.filter(
+                    content_type=ct,
+                    object_id=self.instance.pk
+                ).count(),
+                'content_type': ct,
+                'object_id': self.instance.pk
+            }
+        return self._info
+
+    def get_threads(self):
+        """Get comment threads for this instance."""
+        info = self.get_info()
+        return CommentThread.objects.filter(
+            content_type=info['content_type'],
+            object_id=info['object_id']
+        )
+
+    def add_thread(self, title='', created_by=None):
+        """Create a new comment thread for this instance."""
+        info = self.get_info()
+        thread = CommentThread.objects.create(
+            content_type=info['content_type'],
+            object_id=info['object_id'],
+            title=title,
+            created_by=created_by
+        )
+        self._info = {}  # Clear cache
+        return thread
+
+def get_comment_threads(instance):
+    """Get or create a CommentThreads helper for a model instance."""
+    if not hasattr(instance, '_comment_threads'):
+        instance._comment_threads = CommentThreads(instance)
+    return instance._comment_threads
 
 class Comment(models.Model):
-    """
-    Individual comment within a comment thread.
-    """
+    """Individual comment within a thread."""
     thread = models.ForeignKey(
         CommentThread,
         on_delete=models.CASCADE,