Improved the OpenAI provider (#548)

app/MindWork AI Studio/Provider/OpenAI/ChatCompletionAnnotationStreamLine.cs

@@ -0,0 +1,57 @@
+namespace AIStudio.Provider.OpenAI;
+
+/// <summary>
+/// Represents a line of a chat completion annotation stream.
+/// </summary>
+/// <param name="Id">The unique identifier of the chat completion.</param>
+/// <param name="Object">The type of object returned, typically "chat.completion".</param>
+/// <param name="Created">The creation timestamp of the chat completion in Unix epoch format.</param>
+/// <param name="Model">The model used for the chat completion.</param>
+/// <param name="SystemFingerprint">The system fingerprint associated with the chat completion.</param>
+/// <param name="Choices">The list of choices returned in the chat completion.</param>
+public record ChatCompletionAnnotationStreamLine(string Id, string Object, uint Created, string Model, string SystemFingerprint, IList<ChatCompletionAnnotationChoice> Choices) : IAnnotationStreamLine
+{
+    #region Implementation of IAnnotationStreamLine
+
+    /// <inheritdoc />
+    public bool ContainsSources() => this.Choices.Any(choice => choice.Delta.Annotations is not null && choice.Delta.Annotations.Any(annotation => annotation is not AnnotatingUnknown));
+
+    /// <inheritdoc />
+    public IList<ISource> GetSources()
+    {
+        var sources = new List<ISource>();
+        foreach (var choice in this.Choices)
+        {
+            if (choice.Delta.Annotations is null)
+                continue;
+
+            // Iterate through all annotations:
+            foreach (var annotation in choice.Delta.Annotations)
+            {
+                // Check if the annotation is of the expected type and extract the source information:
+                if (annotation is ChatCompletionAnnotatingURL urlAnnotation)
+                    sources.Add(new Source(urlAnnotation.UrlCitation.Title, urlAnnotation.UrlCitation.URL));
+
+                //
+                // Check for the unexpected annotation type of the Responses API.
+                //
+                // This seems weird at first. But there are two possibilities why this could happen:
+                // - Anyone of the open source providers such as ollama, LM Studio, etc. could
+                //   implement & use the Responses API data structures for annotations in their
+                //   chat completion endpoint.
+                //
+                // - Our custom JSON converter checks for the Responses API data type first. If it
+                //   fails, it checks for the chat completion API data type. So, when the Responses
+                //   API data type is valid, it will be deserialized into that type, even though
+                //   we are calling the chat completion endpoint.
+                //
+                if (annotation is ResponsesAnnotatingUrlCitationData citationData)
+                    sources.Add(new Source(citationData.Title, citationData.URL));
+            }
+        }
+
+        return sources;
+    }
+
+    #endregion
+}