ChatBot/ChatBot.Tests/Services/ModelServiceTests.cs

using ChatBot.Models.Configuration;
using ChatBot.Services;
using ChatBot.Tests.TestUtilities;
using FluentAssertions;
using Microsoft.Extensions.Logging;
using Microsoft.Extensions.Options;
using Moq;

namespace ChatBot.Tests.Services;

public class ModelServiceTests : UnitTestBase
{
    private readonly Mock<ILogger<ModelService>> _loggerMock;
    private readonly Mock<IOptions<OllamaSettings>> _optionsMock;
    private readonly ModelService _modelService;

    public ModelServiceTests()
    {
        _loggerMock = TestDataBuilder.Mocks.CreateLoggerMock<ModelService>();
        var ollamaSettings = TestDataBuilder.Configurations.CreateOllamaSettings();
        _optionsMock = TestDataBuilder.Mocks.CreateOptionsMock(ollamaSettings);

        _modelService = new ModelService(_loggerMock.Object, _optionsMock.Object);
    }

    [Fact]
    public void GetCurrentModel_ShouldReturnDefaultModel()
    {
        // Act
        var result = _modelService.GetCurrentModel();

        // Assert
        result.Should().Be("llama3.2");
    }

    [Fact]
    public async Task InitializeAsync_ShouldLogModelInformation()
    {
        // Act
        var act = async () => await _modelService.InitializeAsync();

        // Assert
        await act.Should()
            .NotThrowAsync("InitializeAsync should complete without throwing exceptions");

        // Verify that logging was called (at least once for model information)
        _loggerMock.Verify(
            x =>
                x.Log(
                    LogLevel.Information,
                    It.IsAny<EventId>(),
                    It.Is<It.IsAnyType>((v, t) => v.ToString()!.Contains("model")),
                    It.IsAny<Exception>(),
                    It.IsAny<Func<It.IsAnyType, Exception?, string>>()
                ),
            Times.AtLeastOnce,
            "Should log model information"
        );
    }
}