Fix timestamps alignment call

src/mfa.py

@@ -12,7 +12,7 @@ _ISTIATHA_TEXT = "أَعُوذُ بِٱللَّهِ مِنَ الشَّيْطَ
 
 def _mfa_upload_and_submit(refs, audio_paths,
                            method=MFA_METHOD, beam=MFA_BEAM, retry_beam=MFA_RETRY_BEAM,
-                           shared_cmvn=MFA_SHARED_CMVN):
+                           shared_cmvn=MFA_SHARED_CMVN, padding="forward"):
     """Upload audio files and submit alignment batch to the MFA Space.
 
     Returns (event_id, headers, base_url) so the caller can yield a progress
@@ -24,6 +24,7 @@ def _mfa_upload_and_submit(refs, audio_paths,
         method: Alignment method ("kalpy", "align_one", "python_api", "cli").
         beam: Viterbi beam width (default 10).
         retry_beam: Retry beam width (default 40).
+        padding: Gap-padding strategy ("forward", "symmetric", "none").
     """
     import requests
 
@@ -59,12 +60,12 @@ def _mfa_upload_and_submit(refs, audio_paths,
         for p in uploaded_paths
     ]
 
-    # Submit batch alignment (extra params map to hidden Gradio Textbox inputs)
+    # Submit batch alignment (7 params: refs, files, method, beam, retry_beam, shared_cmvn, padding)
     submit_resp = requests.post(
         f"{base}/gradio_api/call/align_batch",
         headers={**headers, "Content-Type": "application/json"},
         json={"data": [refs, file_data_list, method, str(beam), str(retry_beam),
-                        str(shared_cmvn).lower()]},
+                        str(shared_cmvn).lower(), padding]},
         timeout=MFA_TIMEOUT,
     )
     submit_resp.raise_for_status()
@@ -91,10 +92,19 @@ def _mfa_wait_result(event_id, headers, base):
         if line and line.startswith("event: "):
             current_event = line[7:]
         elif line and line.startswith("data: "):
+            data_str = line[6:]
             if current_event == "complete":
-                result_data = line[6:]
+                result_data = data_str
             elif current_event == "error":
-                raise RuntimeError(f"MFA align_batch SSE error: {line[6:]}")
+                # Gradio 6.x may send null as error data; provide actionable message
+                if data_str.strip() in ("null", ""):
+                    raise RuntimeError(
+                        "MFA align_batch failed: Space returned null error. "
+                        "This usually means a parameter count mismatch or "
+                        "Gradio input validation failure. Check that the "
+                        "client sends all required parameters."
+                    )
+                raise RuntimeError(f"MFA align_batch SSE error: {data_str}")
 
     if result_data is None:
         raise RuntimeError("No data received from MFA align_batch SSE stream")
@@ -104,6 +114,9 @@ def _mfa_wait_result(event_id, headers, base):
     if isinstance(parsed, list) and len(parsed) == 1:
         parsed = parsed[0]
 
+    if parsed is None:
+        raise RuntimeError("MFA align_batch returned null result")
+
     if not isinstance(parsed, dict) or parsed.get("status") != "ok":
         raise RuntimeError(f"MFA align_batch failed: {parsed}")