// Copyright (c) Microsoft Corporation. All rights reserved.
// OpenAIChatCompletionMiddlewareTests.cs

using System.ClientModel;
using System.ClientModel.Primitives;
using AutoGen.Core;
using AutoGen.OpenAI;
using AutoGen.OpenAI.Extension;
using FluentAssertions;
using Microsoft.AspNetCore.Hosting;
using Microsoft.AspNetCore.TestHost;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.Extensions.Hosting;
using OpenAI;

namespace AutoGen.WebAPI.Tests;

[Trait("Category", "UnitV1")]
public class OpenAIChatCompletionMiddlewareTests
{
    [Fact]
    public async Task ItReturnTextMessageWhenSendTextMessage()
    {
        var agent = new EchoAgent("test");
        var hostBuilder = CreateHostBuilder(agent);
        using var host = await hostBuilder.StartAsync();
        var client = host.GetTestClient();
        var openaiClient = CreateOpenAIClient(client);
        var openAIAgent = new OpenAIChatAgent(openaiClient.GetChatClient("test"), "test")
            .RegisterMessageConnector();

        var response = await openAIAgent.SendAsync("Hey");

        response.GetContent().Should().Be("Hey");
        response.Should().BeOfType<TextMessage>();
        response.From.Should().Be("test");
    }

    [Fact]
    public async Task ItReturnTextMessageWhenSendTextMessageUseStreaming()
    {
        var agent = new EchoAgent("test");
        var hostBuilder = CreateHostBuilder(agent);
        using var host = await hostBuilder.StartAsync();
        var client = host.GetTestClient();
        var openaiClient = CreateOpenAIClient(client);
        var openAIAgent = new OpenAIChatAgent(openaiClient.GetChatClient("test"), "test")
            .RegisterMessageConnector();

        var message = new TextMessage(Role.User, "ABCDEFGHIJKLMN");
        var chunks = new List<IMessage>();
        await foreach (var chunk in openAIAgent.GenerateStreamingReplyAsync([message]))
        {
            chunk.Should().BeOfType<TextMessageUpdate>();
            chunks.Add(chunk);
        }

        var mergedChunks = string.Join("", chunks.Select(c => c.GetContent()));
        mergedChunks.Should().Be("ABCDEFGHIJKLMN");
        chunks.Count.Should().Be(14);
    }

    private IHostBuilder CreateHostBuilder(IAgent agent)
    {
        return new HostBuilder()
            .ConfigureWebHost(webHost =>
            {
                webHost.UseTestServer();
                webHost.Configure(app =>
                {
                    app.UseAgentAsOpenAIChatCompletionEndpoint(agent);
                });
            });
    }

    private OpenAIClient CreateOpenAIClient(HttpClient client)
    {
        return new OpenAIClient(new ApiKeyCredential("api-key"), new OpenAIClientOptions
        {
            Transport = new HttpClientPipelineTransport(client),
        });
    }
}