Set SpecificCharacterSet in C-FIND response

src/services/dicom/__init__.py

@@ -1,5 +1,8 @@
 """DICOM services for PACS functionality."""
 
+# DICOM character sets
+CHARSET_UTF8 = "ISO_IR 192"
+
 # DICOM status codes
 SUCCESS = 0x0000
 FAILURE = 0xC000

src/services/mwl/c_find.py

@@ -10,7 +10,7 @@
 from pydicom import Dataset
 from pynetdicom import evt
 
-from services.dicom import FAILURE, PENDING, SUCCESS
+from services.dicom import CHARSET_UTF8, FAILURE, PENDING, SUCCESS
 from services.storage import MWLStorage, WorklistItem
 
 logger = logging.getLogger(__name__)
@@ -82,6 +82,8 @@ def _build_worklist_response(self, item: WorklistItem) -> Dataset:
         ds = Dataset()
         sps_item = Dataset()
 
+        ds.SpecificCharacterSet = CHARSET_UTF8
+
         # Patient demographics
         ds.PatientID = item.patient_id
         ds.PatientName = item.patient_name

tests/services/mwl/test_c_find.py

@@ -5,7 +5,7 @@
 import pytest
 from pydicom import Dataset
 
-from services.dicom import FAILURE, PENDING, SUCCESS
+from services.dicom import CHARSET_UTF8, FAILURE, PENDING, SUCCESS
 from services.mwl.c_find import CFind
 from services.storage import WorklistItem
 
@@ -71,6 +71,7 @@ def test_call_with_single_result(self, handler, mock_storage, mock_event, sample
         status, ds = results[0]
         assert status == PENDING
         assert isinstance(ds, Dataset)
+        assert ds.SpecificCharacterSet == CHARSET_UTF8
         assert ds.PatientID == "9876543210"
         assert ds.AccessionNumber == "ACC001"
         # Final result: success