using System.Xml.Linq;

namespace AcDream.Launcher.Tests;

public sealed class LauncherProjectBoundaryTests
{
    private static readonly string[] ExpectedAvaloniaPackages =
    [
        "Avalonia",
        "Avalonia.Desktop",
        "Avalonia.Themes.Fluent",
    ];

    [Fact]
    public void LauncherReferencesOnlyLauncherCoreAndPinsOneAvaloniaVersion()
    {
        string root = FindRepositoryRoot();
        string projectPath = Path.Combine(
            root,
            "src",
            "AcDream.Launcher",
            "AcDream.Launcher.csproj");
        XDocument project = XDocument.Load(projectPath);

        string projectReference = Assert.Single(
            project.Descendants("ProjectReference")
                .Select(element => element.Attribute("Include")?.Value ?? string.Empty));
        Assert.EndsWith(
            "AcDream.Launcher.Core\\AcDream.Launcher.Core.csproj",
            projectReference,
            StringComparison.Ordinal);

        (string Name, string Version)[] packages = project
            .Descendants("PackageReference")
            .Select(element => (
                element.Attribute("Include")?.Value ?? string.Empty,
                element.Attribute("Version")?.Value ?? string.Empty))
            .OrderBy(package => package.Item1, StringComparer.Ordinal)
            .ToArray();

        Assert.Equal(ExpectedAvaloniaPackages, packages.Select(package => package.Name));
        Assert.All(packages, package => Assert.Equal("12.1.1", package.Version));
    }

    [Fact]
    public void LauncherAndItsTestsAreSolutionMembers()
    {
        string root = FindRepositoryRoot();
        XDocument solution = XDocument.Load(Path.Combine(root, "AcDream.slnx"));
        string[] paths = solution.Descendants("Project")
            .Select(element => (element.Attribute("Path")?.Value ?? string.Empty)
                .Replace('\\', '/'))
            .ToArray();

        Assert.Contains("src/AcDream.Launcher/AcDream.Launcher.csproj", paths);
        Assert.Contains("tests/AcDream.Launcher.Tests/AcDream.Launcher.Tests.csproj", paths);
    }

    private static string FindRepositoryRoot()
    {
        foreach (string start in new[] { AppContext.BaseDirectory, Environment.CurrentDirectory })
        {
            DirectoryInfo? directory = new(start);
            while (directory is not null)
            {
                if (File.Exists(Path.Combine(directory.FullName, "AcDream.slnx")))
                {
                    return directory.FullName;
                }

                directory = directory.Parent;
            }
        }

        throw new DirectoryNotFoundException("Could not find AcDream.slnx.");
    }
}