using Fengling.Gateway.Plugin.Abstractions;
using Xunit;
using YarpGateway.Plugins;

namespace YarpGateway.Tests.Unit.Plugins;

public class PluginLoaderTests
{
    private string _testBaseDir = null!;

    public PluginLoaderTests()
    {
        _testBaseDir = Path.Combine(Path.GetTempPath(), "plugin-test-" + Guid.NewGuid());
    }

    [Fact]
    public void DiscoverPlugins_EmptyDirectory_ShouldReturnEmpty()
    {
        // Arrange
        var loader = new PluginLoader();
        var emptyDir = Path.Combine(_testBaseDir, "empty");
        Directory.CreateDirectory(emptyDir);

        try
        {
            // Act
            var plugins = loader.DiscoverPlugins(emptyDir).ToList();

            // Assert
            Assert.Empty(plugins);
        }
        finally
        {
            Directory.Delete(_testBaseDir, true);
        }
    }

    [Fact]
    public void DiscoverPlugins_ValidPlugin_ShouldReturnPlugin()
    {
        // Arrange
        var loader = new PluginLoader();
        var pluginDir = Path.Combine(_testBaseDir, "test-plugin");
        Directory.CreateDirectory(pluginDir);

        // 创建 plugin.json
        var manifest = new
        {
            id = "test-plugin",
            name = "Test Plugin",
            version = "1.0.0",
            entryPoint = "TestPlugin.TestPlugin",
            description = "A test plugin"
        };
        var manifestJson = System.Text.Json.JsonSerializer.Serialize(manifest);
        File.WriteAllText(Path.Combine(pluginDir, "plugin.json"), manifestJson);

        // 创建一个占位 DLL
        File.WriteAllText(Path.Combine(pluginDir, "test-plugin.dll"), "dummy");

        try
        {
            // Act
            var plugins = loader.DiscoverPlugins(_testBaseDir).ToList();

            // Assert
            Assert.Single(plugins);
            var plugin = plugins[0];
            Assert.Equal("test-plugin", plugin.Id);
            Assert.Equal("Test Plugin", plugin.Name);
            Assert.Equal("1.0.0", plugin.Version);
        }
        finally
        {
            Directory.Delete(_testBaseDir, true);
        }
    }

    [Fact]
    public void DiscoverPlugins_NoManifest_ShouldSkipPlugin()
    {
        // Arrange
        var loader = new PluginLoader();
        var pluginDir = Path.Combine(_testBaseDir, "test-plugin");
        Directory.CreateDirectory(pluginDir);

        // 只创建 DLL，没有 plugin.json
        File.WriteAllText(Path.Combine(pluginDir, "test-plugin.dll"), "dummy");

        try
        {
            // Act
            var plugins = loader.DiscoverPlugins(_testBaseDir).ToList();

            // Assert
            Assert.Empty(plugins);
        }
        finally
        {
            Directory.Delete(_testBaseDir, true);
        }
    }

    [Fact]
    public void CreateShadowCopy_ShouldCopyFiles()
    {
        // Arrange
        var sourceDir = Path.Combine(_testBaseDir, "source");
        var shadowDir = Path.Combine(_testBaseDir, "shadow");
        Directory.CreateDirectory(sourceDir);

        // 创建源 DLL
        var dllPath = Path.Combine(sourceDir, "TestPlugin.dll");
        File.WriteAllText(dllPath, "dummy dll");

        // 创建 deps.json
        var depsPath = dllPath + ".deps.json";
        File.WriteAllText(depsPath, "{}");

        try
        {
            // Act
            var shadowPath = PluginLoader.CreateShadowCopy(dllPath, shadowDir);

            // Assert
            Assert.True(File.Exists(shadowPath));
            Assert.True(File.Exists(Path.Combine(shadowDir, "TestPlugin.dll.deps.json")));
        }
        finally
        {
            Directory.Delete(_testBaseDir, true);
        }
    }
}