[VertexAI] Refactor the LiveSession responses

vertexai/src/Internal/InternalHelpers.cs

@@ -163,6 +163,26 @@ public static T ParseObject<T>(this JsonDict jsonDict, string key,
     }
   }
 
+  // Tries to convert the found List of objects to a List of strings.
+  public static bool TryParseStringList(this JsonDict jsonDict, string key,
+      out List<string> values,
+      JsonParseOptions options = JsonParseOptions.ThrowInvalidCast) {
+    if (jsonDict.TryParseValue(key, out List<object> list, options)) {
+      values = list.OfType<string>().ToList();
+      return true;
+    } else {
+      values = null;
+      return false;
+    }
+  }
+
+  // Casts the found List to a string List, otherwise returns default (or throws)
+  public static List<string> ParseStringList(this JsonDict jsonDict, string key,
+      JsonParseOptions options = JsonParseOptions.ThrowInvalidCast) {
+    TryParseStringList(jsonDict, key, out List<string> values, options);
+    return values;
+  }
+
   // Tries to convert the found List of Dictionaries, using the given function.
   public static bool TryParseObjectList<T>(this JsonDict jsonDict, string key,
       Func<JsonDict, T> parseFunc, out List<T> values,

vertexai/src/LiveSession.cs

@@ -175,7 +175,7 @@ public Task SendAudioAsync(float[] audioData, CancellationToken cancellationToke
   /// <param name="closeOnTurnComplete">Should the stream stop when the server returns TurnComplete.</param>
   /// <param name="cancellationToken">A token to cancel the operation.</param>
   /// <returns>A stream of `LiveContentResponse`s from the backend.</returns>
-  public async IAsyncEnumerable<LiveContentResponse> ReceiveAsync(
+  public async IAsyncEnumerable<LiveSessionResponse> ReceiveAsync(
       bool closeOnTurnComplete = true,
       [EnumeratorCancellation] CancellationToken cancellationToken = default) {
     if (_clientWebSocket.State != WebSocketState.Open) {
@@ -199,14 +199,16 @@ public async IAsyncEnumerable<LiveContentResponse> ReceiveAsync(
         messageBuilder.Append(Encoding.UTF8.GetString(receiveBuffer, 0, result.Count));
 
         if (result.EndOfMessage) {
-          LiveContentResponse? response = LiveContentResponse.FromJson(messageBuilder.ToString());
+          LiveSessionResponse? response = LiveSessionResponse.FromJson(messageBuilder.ToString());
           // Reset for the next message.
           messageBuilder.Clear();
 
           if (response != null) {
             yield return response.Value;
 
-            if (closeOnTurnComplete && response?.Status == LiveContentResponse.LiveResponseStatus.TurnComplete) {
+            if (closeOnTurnComplete &&
+                response?.Message is LiveSessionContent serverContent &&
+                serverContent.TurnComplete) {
               break;
             }
           }