fix recording timing and sync call contracts

agent_call/real_cell.py

@@ -11,6 +11,7 @@ from __future__ import annotations
 import base64
 import contextlib
 import http.client
+import io
 import ipaddress
 import json
 import os
@@ -23,6 +24,7 @@ import struct
 import threading
 import time
 import uuid
+import wave
 from collections.abc import Mapping
 from dataclasses import dataclass, field
 from pathlib import Path
@@ -618,6 +620,8 @@ class RealCellCall:
             )
             self.target_channel_id = self._channel_id(target)
             self._add_when_ready(self.target_channel_id)
+            self._wait_answer(result)
+            result.connected = True
             self.ari.request(
                 "POST",
                 f"bridges/{self.bridge_id}/record",
@@ -628,8 +632,6 @@ class RealCellCall:
                     "beepEnabled": False,
                 },
             )
-            self._wait_answer(result)
-            result.connected = True
             opening = str(self.engine.config["conversation"].get("opening", ""))
             if opening:
                 opening_result = self.engine.speak(opening, f"opening_{self.call_id}")
@@ -1016,6 +1018,13 @@ class RealCellCall:
             return None
         if not isinstance(raw, bytes) or not raw:
             return None
+        try:
+            with wave.open(io.BytesIO(raw), "rb") as source:
+                frames = source.getnframes()
+        except (EOFError, OSError, wave.Error):
+            return None
+        if not frames > 0:
+            return None
         path = Path(self.config.recording_dir) / f"{self.recording_name}.wav"
         try:
             if path.is_symlink():