New comparison feature.

modules/web_tasks.py

@@ -367,4 +367,45 @@ def rewrite_chapter_task(run_id, project_path, book_folder, chap_num, instructio
         return False
     except Exception as e:
         utils.log("ERROR", f"Rewrite task exception for run {run_id}/{book_folder}: {e}")
+        return False
+
+@huey.task()
+def refine_bible_task(project_path, instruction, source_type, selected_keys=None):
+    """
+    Background task to refine the Bible.
+    Handles partial merging of selected keys into a temp base before refinement.
+    """
+    try:
+        bible_path = os.path.join(project_path, "bible.json")
+        draft_path = os.path.join(project_path, "bible_draft.json")
+        
+        base_bible = utils.load_json(bible_path)
+        if not base_bible: return False
+
+        # If refining from draft, load it
+        if source_type == 'draft' and os.path.exists(draft_path):
+            draft_bible = utils.load_json(draft_path)
+            
+            # If user selected specific changes, merge them into the base
+            # This creates a "Proposed State" to refine further, WITHOUT modifying bible.json
+            if selected_keys and draft_bible:
+                base_bible = story.merge_selected_changes(base_bible, draft_bible, selected_keys)
+            elif draft_bible:
+                # If no specific keys but source is draft, assume we refine the whole draft
+                base_bible = draft_bible
+
+        ai.init_models()
+        
+        # Run AI Refinement
+        new_bible = story.refine_bible(base_bible, instruction, project_path)
+        
+        if new_bible:
+            # Save to draft file (Overwrite previous draft)
+            with open(draft_path, 'w') as f: json.dump(new_bible, f, indent=2)
+            return True
+            
+        return False
+
+    except Exception as e:
+        utils.log("ERROR", f"Bible refinement task failed: {e}")
         return False