changes to the decryption of the payloads from the audit event report download

Web/app.py

@@ -8220,11 +8220,26 @@ def admin_audit_export_pdf_official():
 
         audit_rows = list(db['audit_log'].find({}).sort('chain_index', -1).limit(limit))
 
-        # DEC_START: Decrypt sensitive fields for the PDF report
         for row in audit_rows:
-            if "payload" in row:
-                decrypt_document_fields(row["payload"], SENSITIVE_AUDIT_FIELDS)
-        # DEC_END
+            payload_raw = row.get("payload")
+            
+            if payload_raw and isinstance(payload_raw, str):
+                try:
+                    # Safely evaluate the python-like dict string with custom token support
+                    safe_context = {"ObjectId": ObjectId, "None": None, "True": True, "False": False}
+                    payload_dict = eval(payload_raw, {"__builtins__": {}}, safe_context)
+                    
+                    if isinstance(payload_dict, dict):
+                        # Decrypt the dictionary fields in-place
+                        decrypt_document_fields(payload_dict, SENSITIVE_AUDIT_FIELDS)
+                        # Replace string with the clean dictionary so the PDF generator can read it
+                        row["payload"] = payload_dict
+                except Exception as parse_err:
+                    app.logger.error(f"Failed to parse audit payload string for PDF export at index {row.get('chain_index')}: {parse_err}")
+            
+            elif payload_raw and isinstance(payload_raw, dict):
+                # Fallback for standard dict payloads
+                decrypt_document_fields(payload_raw, SENSITIVE_AUDIT_FIELDS)
 
         # Get school information from settings or use defaults
         school_info = _get_school_info_for_export()