using AcDream.Core.Plugins;
using AcDream.Plugin.Abstractions;

namespace AcDream.Core.Tests.Plugins;

public class PluginLoaderTests
{
    private static string FixturePluginPath()
    {
        // walk up from the test bin dir to the repo root, then into the fixture's build output
        var baseDir = AppContext.BaseDirectory;
        var configuration = new DirectoryInfo(baseDir).Parent!.Name; // Debug / Release
        var repoRoot = FindRepoRoot(baseDir);
        return Path.Combine(
            repoRoot,
            "tests", "AcDream.Core.Tests.Fixtures.HelloPlugin", "bin", configuration, "net10.0",
            "AcDream.Core.Tests.Fixtures.HelloPlugin.dll");
    }

    private static string FindRepoRoot(string startDir)
    {
        var dir = new DirectoryInfo(startDir);
        while (dir is not null && !File.Exists(Path.Combine(dir.FullName, "AcDream.slnx")))
            dir = dir.Parent;
        return dir?.FullName ?? throw new InvalidOperationException("repo root not found");
    }

    private sealed class StubHost : IPluginHost
    {
        public IPluginLogger Log { get; } = new StubLogger();
    }

    private sealed class StubLogger : IPluginLogger
    {
        public void Info(string message) { }
        public void Warn(string message) { }
        public void Error(string message, Exception? exception = null) { }
    }

    [Fact]
    public void Load_FixtureDll_InstantiatesPluginAndCallsInitialize()
    {
        var dllPath = FixturePluginPath();
        Assert.True(File.Exists(dllPath), $"fixture dll not found: {dllPath}");

        var host = new StubHost();
        var manifest = new PluginManifest(
            Id: "acdream.test.hello",
            DisplayName: "Hello",
            Version: "0.0.1",
            EntryDll: Path.GetFileName(dllPath),
            ApiVersion: 1,
            Dependencies: Array.Empty<string>());

        var loaded = PluginLoader.Load(
            pluginDirectory: Path.GetDirectoryName(dllPath)!,
            manifest: manifest,
            host: host);

        Assert.True(loaded.Success);
        Assert.NotNull(loaded.Plugin);
        Assert.Equal("HelloPlugin", loaded.Plugin!.GetType().Name);
    }

    [Fact]
    public void Load_MissingDll_ReturnsFailure()
    {
        var host = new StubHost();
        var manifest = new PluginManifest(
            Id: "x",
            DisplayName: "X",
            Version: "0.0.1",
            EntryDll: "nope.dll",
            ApiVersion: 1,
            Dependencies: Array.Empty<string>());

        var loaded = PluginLoader.Load("/does/not/exist", manifest, host);

        Assert.False(loaded.Success);
        Assert.NotNull(loaded.Error);
    }

    [Fact]
    public void Load_DllWithNoPluginImpl_ReturnsFailure()
    {
        // Use AcDream.Core.dll itself — it has no IAcDreamPlugin impl
        var coreDllDir = AppContext.BaseDirectory;
        var host = new StubHost();
        var manifest = new PluginManifest(
            Id: "x",
            DisplayName: "X",
            Version: "0.0.1",
            EntryDll: "AcDream.Core.dll",
            ApiVersion: 1,
            Dependencies: Array.Empty<string>());

        var loaded = PluginLoader.Load(coreDllDir, manifest, host);

        Assert.False(loaded.Success);
        Assert.Contains("IAcDreamPlugin", loaded.Error!.Message);
    }
}