agent-framework/dotnet/tests/Microsoft.Agents.AI.Foundry.UnitTests/FoundryAgentTests.cs

// Copyright (c) Microsoft. All rights reserved.

using System;
using System.ClientModel.Primitives;
using System.Net;
using System.Net.Http;
using System.Text;
using System.Threading;
using System.Threading.Tasks;
using Azure.AI.Projects;
using Microsoft.Extensions.AI;

namespace Microsoft.Agents.AI.Foundry.UnitTests;

/// <summary>
/// Unit tests for the <see cref="FoundryAgent"/> class.
/// </summary>
public class FoundryAgentTests
{
    private static readonly Uri s_testEndpoint = new("https://test.services.ai.azure.com/api/projects/test-project");

    #region Constructor validation tests

    [Fact]
    public void Constructor_WithNullEndpoint_ThrowsArgumentNullException()
    {
        ArgumentNullException exception = Assert.Throws<ArgumentNullException>(() =>
            new FoundryAgent(
                projectEndpoint: null!,
                credential: new FakeAuthenticationTokenProvider(),
                model: "gpt-4o-mini",
                instructions: "Test instructions"));

        Assert.Equal("endpoint", exception.ParamName);
    }

    [Fact]
    public void Constructor_WithNullCredential_ThrowsArgumentNullException()
    {
        ArgumentNullException exception = Assert.Throws<ArgumentNullException>(() =>
            new FoundryAgent(
                projectEndpoint: s_testEndpoint,
                credential: null!,
                model: "gpt-4o-mini",
                instructions: "Test instructions"));

        Assert.Equal("credential", exception.ParamName);
    }

    [Fact]
    public void Constructor_WithNullModel_ThrowsArgumentException()
    {
        Assert.ThrowsAny<ArgumentException>(() =>
            new FoundryAgent(
                projectEndpoint: s_testEndpoint,
                credential: new FakeAuthenticationTokenProvider(),
                model: null!,
                instructions: "Test instructions"));
    }

    [Fact]
    public void Constructor_WithEmptyModel_ThrowsArgumentException()
    {
        Assert.ThrowsAny<ArgumentException>(() =>
            new FoundryAgent(
                projectEndpoint: s_testEndpoint,
                credential: new FakeAuthenticationTokenProvider(),
                model: string.Empty,
                instructions: "Test instructions"));
    }

    [Fact]
    public void Constructor_WithNullInstructions_ThrowsArgumentException()
    {
        Assert.ThrowsAny<ArgumentException>(() =>
            new FoundryAgent(
                projectEndpoint: s_testEndpoint,
                credential: new FakeAuthenticationTokenProvider(),
                model: "gpt-4o-mini",
                instructions: null!));
    }

    [Fact]
    public void Constructor_WithValidParams_CreatesAgent()
    {
        FoundryAgent agent = new(
            s_testEndpoint,
            new FakeAuthenticationTokenProvider(),
            model: "gpt-4o-mini",
            instructions: "You are a helpful assistant.",
            name: "test-agent",
            description: "A test agent");

        Assert.NotNull(agent);
        Assert.Equal("test-agent", agent.Name);
        Assert.Equal("A test agent", agent.Description);
    }

    #endregion

    #region Property tests

    [Fact]
    public void Name_ReturnsConfiguredName()
    {
        FoundryAgent agent = new(
            s_testEndpoint,
            new FakeAuthenticationTokenProvider(),
            model: "gpt-4o-mini",
            instructions: "Test",
            name: "my-agent");

        Assert.Equal("my-agent", agent.Name);
    }

    [Fact]
    public void Description_ReturnsConfiguredDescription()
    {
        FoundryAgent agent = new(
            s_testEndpoint,
            new FakeAuthenticationTokenProvider(),
            model: "gpt-4o-mini",
            instructions: "Test",
            description: "Agent description");

        Assert.Equal("Agent description", agent.Description);
    }

    [Fact]
    public void GetService_ReturnsAIProjectClient()
    {
        FoundryAgent agent = new(
            s_testEndpoint,
            new FakeAuthenticationTokenProvider(),
            model: "gpt-4o-mini",
            instructions: "Test");

        AIProjectClient? client = agent.GetService<AIProjectClient>();

        Assert.NotNull(client);
    }

    [Fact]
    public void GetService_ReturnsChatClientAgent()
    {
        FoundryAgent agent = new(
            s_testEndpoint,
            new FakeAuthenticationTokenProvider(),
            model: "gpt-4o-mini",
            instructions: "Test");

        ChatClientAgent? innerAgent = agent.GetService<ChatClientAgent>();

        Assert.NotNull(innerAgent);
    }

    [Fact]
    public void Constructor_PreWiresClientHeadersAgent()
    {
        // Arrange / Act: the public FoundryAgent ctor should pre-wire the client-headers
        // pipeline so x-client-* headers stamped on ChatClientAgentRunOptions reach the wire.
        FoundryAgent agent = new(
            s_testEndpoint,
            new FakeAuthenticationTokenProvider(),
            model: "gpt-4o-mini",
            instructions: "Test");

        // Assert: ClientHeadersAgent decorator is present in the delegating chain.
        Assert.NotNull(agent.GetService<ClientHeadersAgent>());
    }

    [Fact]
    public void Constructor_FromAsAIAgentExtension_PreWiresClientHeadersAgent()
    {
        // Arrange: stand up a real AIProjectClient pointed at a fake transport.
        using var handler = new NoopHandler();
#pragma warning disable CA5399
        using var http = new HttpClient(handler);
#pragma warning restore CA5399
        var projectClient = new AIProjectClient(
            s_testEndpoint,
            new FakeAuthenticationTokenProvider(),
            new AIProjectClientOptions { Transport = new HttpClientPipelineTransport(http) });

        // Act: this AsAIAgent path constructs FoundryAgent via its internal
        // (AIProjectClient, ChatClientAgent) constructor, which previously bypassed pre-wiring.
        var agent = projectClient.AsAIAgent(new Azure.AI.Extensions.OpenAI.AgentReference("agent-name"));

        // Assert
        Assert.NotNull(agent.GetService<ClientHeadersAgent>());
    }

    private sealed class NoopHandler : HttpClientHandler
    {
        protected override Task<HttpResponseMessage> SendAsync(HttpRequestMessage request, CancellationToken cancellationToken)
            => Task.FromResult(new HttpResponseMessage(HttpStatusCode.OK));
    }

    [Fact]
    public void GetService_ReturnsIChatClient()
    {
        FoundryAgent agent = new(
            s_testEndpoint,
            new FakeAuthenticationTokenProvider(),
            model: "gpt-4o-mini",
            instructions: "Test");

        IChatClient? chatClient = agent.GetService<IChatClient>();

        Assert.NotNull(chatClient);
    }

    [Fact]
    public void GetService_ReturnsChatClientMetadata()
    {
        FoundryAgent agent = new(
            s_testEndpoint,
            new FakeAuthenticationTokenProvider(),
            model: "gpt-4o-mini",
            instructions: "Test");

        ChatClientMetadata? metadata = agent.GetService<ChatClientMetadata>();

        Assert.NotNull(metadata);
        Assert.Equal("microsoft.foundry", metadata.ProviderName);
    }

    [Fact]
    public void GetService_ReturnsNullForUnknownType()
    {
        FoundryAgent agent = new(
            s_testEndpoint,
            new FakeAuthenticationTokenProvider(),
            model: "gpt-4o-mini",
            instructions: "Test");

        Assert.Null(agent.GetService<HttpClient>());
    }

    #endregion

    #region CreateSessionAsync tests

    [Fact]
    public async Task CreateSessionAsync_WithConversationId_ReturnsChatClientAgentSessionAsync()
    {
        // Arrange
        FoundryAgent agent = new(
            s_testEndpoint,
            new FakeAuthenticationTokenProvider(),
            model: "gpt-4o-mini",
            instructions: "Test");

        const string ConversationId = "test-conversation-id";

        // Act
        AgentSession session = await agent.CreateSessionAsync(ConversationId);

        // Assert
        ChatClientAgentSession chatSession = Assert.IsType<ChatClientAgentSession>(session);
        Assert.Equal(ConversationId, chatSession.ConversationId);
    }

    [Fact]
    public async Task CreateSessionAsync_WithoutConversationId_ReturnsChatClientAgentSessionWithoutConversationIdAsync()
    {
        // Arrange
        FoundryAgent agent = new(
            s_testEndpoint,
            new FakeAuthenticationTokenProvider(),
            model: "gpt-4o-mini",
            instructions: "Test");

        // Act
        AgentSession session = await agent.CreateSessionAsync();

        // Assert
        ChatClientAgentSession chatSession = Assert.IsType<ChatClientAgentSession>(session);
        Assert.Null(chatSession.ConversationId);
    }

    #endregion

    #region Functional tests

    [Fact]
    public async Task RunAsync_SendsRequestToResponsesAPIAsync()
    {
        bool requestTriggered = false;
        using HttpHandlerAssert httpHandler = new(request =>
        {
            if (request.Method == HttpMethod.Post && request.RequestUri!.PathAndQuery.Contains("/responses"))
            {
                requestTriggered = true;
                return new HttpResponseMessage(HttpStatusCode.OK)
                {
                    Content = new StringContent(
                        TestDataUtil.GetOpenAIDefaultResponseJson(),
                        Encoding.UTF8,
                        "application/json")
                };
            }

            return new HttpResponseMessage(HttpStatusCode.OK)
            {
                Content = new StringContent("{}", Encoding.UTF8, "application/json")
            };
        });

#pragma warning disable CA5399
        using HttpClient httpClient = new(httpHandler);
#pragma warning restore CA5399

        AIProjectClientOptions clientOptions = new()
        {
            Transport = new HttpClientPipelineTransport(httpClient)
        };

        FoundryAgent agent = new(
            s_testEndpoint,
            new FakeAuthenticationTokenProvider(),
            model: "gpt-4o-mini",
            instructions: "You are a helpful assistant.",
            clientOptions: clientOptions);

        AgentSession session = await agent.CreateSessionAsync();
        await agent.RunAsync("Hello", session);

        Assert.True(requestTriggered);
    }

    [Fact]
    public void Constructor_WithChatClientFactory_AppliesFactory()
    {
        bool factoryCalled = false;

        FoundryAgent agent = new(
            s_testEndpoint,
            new FakeAuthenticationTokenProvider(),
            model: "gpt-4o-mini",
            instructions: "Test",
            clientFactory: client =>
            {
                factoryCalled = true;
                return client;
            });

        Assert.True(factoryCalled);
        Assert.NotNull(agent);
    }

    [Fact]
    public async Task Constructor_UserAgentHeaderAddedToRequestsAsync()
    {
        bool userAgentFound = false;
        using HttpHandlerAssert httpHandler = new(request =>
        {
            if (request.Headers.TryGetValues("User-Agent", out System.Collections.Generic.IEnumerable<string>? values))
            {
                foreach (string value in values)
                {
                    if (value.StartsWith("MEAI/", StringComparison.OrdinalIgnoreCase))
                    {
                        userAgentFound = true;
                    }
                }
            }

            return new HttpResponseMessage(HttpStatusCode.OK)
            {
                Content = new StringContent(
                    TestDataUtil.GetOpenAIDefaultResponseJson(),
                    Encoding.UTF8,
                    "application/json")
            };
        });

#pragma warning disable CA5399
        using HttpClient httpClient = new(httpHandler);
#pragma warning restore CA5399

        AIProjectClientOptions clientOptions = new()
        {
            Transport = new HttpClientPipelineTransport(httpClient)
        };

        FoundryAgent agent = new(
            s_testEndpoint,
            new FakeAuthenticationTokenProvider(),
            model: "gpt-4o-mini",
            instructions: "Test",
            clientOptions: clientOptions);

        AgentSession session = await agent.CreateSessionAsync();
        await agent.RunAsync("Hello", session);

        Assert.True(userAgentFound, "Expected MEAI user-agent header to be present in requests.");
    }

    #endregion
}