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

namespace ChatBot.Tests.Services.HealthChecks;

public class OllamaHealthCheckTests : UnitTestBase
{
    private readonly Mock<ILogger<OllamaHealthCheck>> _loggerMock;
    private readonly Mock<IOllamaClient> _ollamaClientMock;
    private readonly OllamaHealthCheck _healthCheck;

    public OllamaHealthCheckTests()
    {
        _loggerMock = TestDataBuilder.Mocks.CreateLoggerMock<OllamaHealthCheck>();
        _ollamaClientMock = TestDataBuilder.Mocks.CreateOllamaClientMock();

        _healthCheck = new OllamaHealthCheck(_ollamaClientMock.Object, _loggerMock.Object);
    }

    [Fact]
    public async Task CheckHealthAsync_ShouldReturnHealthy_WhenOllamaResponds()
    {
        // Arrange
        _ollamaClientMock
            .Setup(x => x.ListLocalModelsAsync())
            .ReturnsAsync(
                new List<OllamaSharp.Models.Model>
                {
                    new OllamaSharp.Models.Model { Name = "llama3.2" },
                }
            );

        // Act
        var context = new HealthCheckContext();
        var result = await _healthCheck.CheckHealthAsync(context);

        // Assert
        result.Status.Should().Be(HealthStatus.Healthy);
    }

    [Fact]
    public async Task CheckHealthAsync_ShouldReturnUnhealthy_WhenOllamaThrowsException()
    {
        // Arrange
        _ollamaClientMock
            .Setup(x => x.ListLocalModelsAsync())
            .ThrowsAsync(new Exception("Ollama unavailable"));

        // Act
        var context = new HealthCheckContext();
        var result = await _healthCheck.CheckHealthAsync(context);

        // Assert
        result.Status.Should().Be(HealthStatus.Unhealthy);
    }

    [Fact]
    public async Task CheckHealthAsync_ShouldReturnUnhealthy_WhenOllamaReturnsEmptyResponse()
    {
        // Arrange
        _ollamaClientMock
            .Setup(x => x.ListLocalModelsAsync())
            .ReturnsAsync(new List<OllamaSharp.Models.Model>());

        // Act
        var context = new HealthCheckContext();
        var result = await _healthCheck.CheckHealthAsync(context);

        // Assert
        result.Status.Should().Be(HealthStatus.Unhealthy);
    }

    [Fact]
    public async Task CheckHealthAsync_ShouldReturnUnhealthy_WhenOllamaReturnsNullMessage()
    {
        // Arrange
        _ollamaClientMock
            .Setup(x => x.ListLocalModelsAsync())
            .ReturnsAsync((IEnumerable<OllamaSharp.Models.Model>)null!);

        // Act
        var context = new HealthCheckContext();
        var result = await _healthCheck.CheckHealthAsync(context);

        // Assert
        result.Status.Should().Be(HealthStatus.Unhealthy);
    }
}