From 422719f509fe456cd808cad78473f3b76e9a94d2 Mon Sep 17 00:00:00 2001
From: Stevan Freeborn <65925598+StevanFreeborn@users.noreply.github.com>
Date: Fri, 28 Jun 2024 10:53:36 -0500
Subject: [PATCH] fix: move client to top level namespace

---
 src/AnthropicClient/{Models => }/Client.cs | 77 +++++++++++++++++++++-
 1 file changed, 74 insertions(+), 3 deletions(-)
 rename src/AnthropicClient/{Models => }/Client.cs (54%)

diff --git a/src/AnthropicClient/Models/Client.cs b/src/AnthropicClient/Client.cs
similarity index 54%
rename from src/AnthropicClient/Models/Client.cs
rename to src/AnthropicClient/Client.cs
index ba00ae2..a3cf0b8 100644
--- a/src/AnthropicClient/Models/Client.cs
+++ b/src/AnthropicClient/Client.cs
@@ -4,8 +4,9 @@ using System.Text.Json;
 
 using AnthropicClient.Json;
 using AnthropicClient.Utils;
+using AnthropicClient.Models;
 
-namespace AnthropicClient.Models;
+namespace AnthropicClient;
 
 /// <summary>
 /// Represents a client for interacting with the Anthropic API.
@@ -18,6 +19,13 @@ public interface IClient
   /// <param name="request">The chat message request to create.</param>
   /// <returns>A task that represents the asynchronous operation. The task result contains the chat response as an <see cref="AnthropicResult{T}"/>.</returns>
   Task<AnthropicResult<ChatResponse>> CreateChatMessageAsync(ChatMessageRequest request);
+
+  /// <summary>
+  /// Creates a chat message asynchronously and streams the response.
+  /// </summary>
+  /// <param name="request">The chat message request to create.</param>
+  /// <returns>An asynchronous enumerable that yields the chat response line by line.</returns>
+  IAsyncEnumerable<AnthropicEvent> CreateChatMessageAsync(StreamChatMessageRequest request);
 }
 
 /// <inheritdoc cref="IClient"/>
@@ -62,8 +70,7 @@ public class Client : IClient
   /// <inheritdoc />
   public async Task<AnthropicResult<ChatResponse>> CreateChatMessageAsync(ChatMessageRequest request)
   {
-    var requestContent = new StringContent(Serialize(request), Encoding.UTF8, JsonContentType);
-    var response = await _httpClient.PostAsync(MessagesEndpoint, requestContent);
+    var response = await SendRequestAsync(request);
     var requestId = GetRequestId(response);
     var responseContent = await response.Content.ReadAsStringAsync();
 
@@ -77,6 +84,70 @@ public class Client : IClient
     return AnthropicResult<ChatResponse>.Success(chatResponse, requestId);
   }
 
+  /// <inheritdoc />
+  public async IAsyncEnumerable<AnthropicEvent> CreateChatMessageAsync(StreamChatMessageRequest request)
+  {
+    var response = await SendRequestAsync(request);
+    var requestId = GetRequestId(response);
+
+    using var responseContent = await response.Content.ReadAsStreamAsync();
+    using var streamReader = new StreamReader(responseContent);
+
+    var currentEvent = new AnthropicEvent();
+
+    // TODO: I'd like to emit custom events unique to this client
+    // - "content_block_complete"
+    //   - provides the complete content block that was streamed
+    //   - useful for streaming in text, but then handling tool calls with their entire input
+
+    // will need to keep track of current content so that we can build it up as relevant
+    // deltas are streamed in
+
+    // will want to capture the content block start event
+    // then continue to build this up until we get to the content block stop event
+    // at that point we should have the complete block and we should be able to yield
+    // return the complete block and reset the current content block
+    
+    // event: content_block_start
+    // data: {"type":"content_block_start","index":1,"content_block":{"type":"tool_use","id":"toolu_01T1x1fJ34qAmk2tNTrN7Up6","name":"get_weather","input":{}}}
+
+
+    do
+    {
+      var line = await streamReader.ReadLineAsync();
+      
+      if (line is null)
+      {
+        break;
+      }
+
+      if (line.StartsWith("event:"))
+      {
+        var eventType = line.Substring("event:".Length).Trim();
+        currentEvent = currentEvent with { Type = eventType };
+      }
+
+      if (line.StartsWith("data:"))
+      {
+        var eventData = line.Substring("data:".Length).Trim();
+        var eventDataJson = JsonSerializer.Deserialize<EventData>(eventData, JsonSerializationOptions.DefaultOptions);
+        currentEvent = currentEvent with { Data = eventDataJson! };
+      }
+
+      if (line == string.Empty)
+      {
+        yield return currentEvent;
+        currentEvent = new AnthropicEvent();
+      }
+    } while (true);
+  }
+
+  private async Task<HttpResponseMessage> SendRequestAsync(MessageRequest request)
+  {
+    var requestContent = new StringContent(Serialize(request), Encoding.UTF8, JsonContentType);
+    return await _httpClient.PostAsync(MessagesEndpoint, requestContent);
+  }
+
   private string Serialize<T>(T obj) => JsonSerializer.Serialize(obj, JsonSerializationOptions.DefaultOptions);
   private T? Deserialize<T>(string json) => JsonSerializer.Deserialize<T>(json, JsonSerializationOptions.DefaultOptions);
   private string GetRequestId(HttpResponseMessage response) => response.Headers.GetValues(RequestIdHeader).FirstOrDefault() ?? string.Empty;