using Microsoft.Extensions.Logging;
using Microsoft.Extensions.Options;
using RobotNet10.FleetManager.Services;
using RobotNet10.StorageManager;
using System.Text;

namespace RobotNet10.RobotManager.Test.Services;

/// <summary>
/// Unit tests for RobotModelImageStorageService
/// </summary>
[TestFixture]
public class RobotModelImageStorageServiceTests
{
    private string _testDirectory = null!;
    private RobotModelImageStorageService _service = null!;
    private IOptionsMonitor<StorageConfig> _optionsMonitor = null!;

    [SetUp]
    public void Setup()
    {
        // Create a temporary test directory
        _testDirectory = Path.Combine(Path.GetTempPath(), Guid.NewGuid().ToString());
        Directory.CreateDirectory(_testDirectory);

        // Create StorageConfig for local storage
        var storageConfig = new StorageConfig
        {
            UsingLocal = true,
            LocalFolder = _testDirectory,
            RetryCount = 3
        };

        // Mock IOptionsMonitor<StorageConfig>
        var mockOptionsMonitor = new Moq.Mock<IOptionsMonitor<StorageConfig>>();
        mockOptionsMonitor.Setup(m => m.Get("RobotModelImages")).Returns(storageConfig);

        _optionsMonitor = mockOptionsMonitor.Object;
        var logger = new LoggerFactory().CreateLogger<RobotModelImageStorageService>();
        _service = new RobotModelImageStorageService(_optionsMonitor, logger);
    }

    [TearDown]
    public void TearDown()
    {
        // Dispose service to clean up StorageManager
        _service?.Dispose();

        // Clean up test directory
        if (Directory.Exists(_testDirectory))
        {
            Directory.Delete(_testDirectory, true);
        }
    }

    [Test]
    public async Task SaveImageAsync_ValidImage_SavesToFileSystem()
    {
        // Arrange
        var robotModelId = Guid.NewGuid();
        var imageBytes = Encoding.UTF8.GetBytes("Fake PNG image data");
        using var imageStream = new MemoryStream(imageBytes);

        // Act
        await _service.SaveImageAsync(robotModelId, imageStream);

        // Assert
        // StorageManager stores files in path "robotModelImages" with objectName = robotModelId
        var expectedPath = Path.Combine(_testDirectory, "robotModelImages", $"{robotModelId}.png");
        Assert.That(File.Exists(expectedPath), Is.True);
    }

    [Test]
    public async Task GetImageAsync_ExistingImage_ReturnsStream()
    {
        // Arrange
        var robotModelId = Guid.NewGuid();
        var imageBytes = Encoding.UTF8.GetBytes("Fake PNG image data");
        using var saveStream = new MemoryStream(imageBytes);
        await _service.SaveImageAsync(robotModelId, saveStream);

        // Act
        using var result = await _service.GetImageAsync(robotModelId);

        // Assert
        Assert.That(result, Is.Not.Null);
        Assert.That(result, Is.InstanceOf<Stream>());
        Assert.That(result!.Length, Is.GreaterThan(0));
    }

    [Test]
    public async Task GetImageAsync_NonExistentImage_ReturnsNull()
    {
        // Arrange
        var nonExistentId = Guid.NewGuid();

        // Act
        var result = await _service.GetImageAsync(nonExistentId);

        // Assert
        Assert.That(result, Is.Null);
    }

    [Test]
    public async Task DeleteImageAsync_ExistingImage_DeletesFile()
    {
        // Arrange
        var robotModelId = Guid.NewGuid();
        var imageBytes = Encoding.UTF8.GetBytes("Fake PNG image data");
        using var saveStream = new MemoryStream(imageBytes);
        await _service.SaveImageAsync(robotModelId, saveStream);

        // Act
        await _service.DeleteImageAsync(robotModelId);

        // Assert
        // StorageManager stores files in path "robotModelImages" with objectName = robotModelId
        var expectedPath = Path.Combine(_testDirectory, "robotModelImages", $"{robotModelId}.png");
        Assert.That(File.Exists(expectedPath), Is.False);
    }

    [Test]
    public async Task DeleteImageAsync_NonExistentImage_DoesNotThrow()
    {
        // Arrange
        var nonExistentId = Guid.NewGuid();

        // Act & Assert - Should not throw
        Assert.DoesNotThrowAsync(async () => await _service.DeleteImageAsync(nonExistentId));
    }

    [Test]
    public async Task ImageExistsAsync_ExistingImage_ReturnsTrue()
    {
        // Arrange
        var robotModelId = Guid.NewGuid();
        var imageBytes = Encoding.UTF8.GetBytes("Fake PNG image data");
        using var saveStream = new MemoryStream(imageBytes);
        await _service.SaveImageAsync(robotModelId, saveStream);

        // Act
        var result = await _service.ImageExistsAsync(robotModelId);

        // Assert
        Assert.That(result, Is.True);
    }

    [Test]
    public async Task ImageExistsAsync_NonExistentImage_ReturnsFalse()
    {
        // Arrange
        var nonExistentId = Guid.NewGuid();

        // Act
        var result = await _service.ImageExistsAsync(nonExistentId);

        // Assert
        Assert.That(result, Is.False);
    }

    [Test]
    public async Task GetImageDimensionsAsync_InvalidImageStream_ThrowsException()
    {
        // Arrange
        // Note: This test uses invalid image data to verify error handling
        var imageBytes = Encoding.UTF8.GetBytes("Invalid image data");
        using var imageStream = new MemoryStream(imageBytes);

        // Act & Assert
        // Since we're using invalid image data, this should throw InvalidOperationException
        // (which wraps UnknownImageFormatException from ImageSharp)
        var ex = Assert.ThrowsAsync<InvalidOperationException>(async () => 
            await _service.GetImageDimensionsAsync(imageStream));
        Assert.That(ex!.Message, Does.Contain("Invalid image format or corrupted file"));
    }
}