using System.Text.RegularExpressions;

namespace AcDream.App.Tests.Runtime;

public sealed class RuntimeMovementOwnershipTests
{
    [Fact]
    public void ProductionConstructsOneCanonicalRuntimeMovementOwner()
    {
        string root = FindRepositoryRoot();
        string appRoot = Path.Combine(root, "src", "AcDream.App");
        string runtimeRoot = Path.Combine(root, "src", "AcDream.Runtime");
        string app = string.Join(
            "\n",
            Directory.EnumerateFiles(appRoot, "*.cs", SearchOption.AllDirectories)
                .Select(File.ReadAllText));
        string runtime = string.Join(
            "\n",
            Directory.EnumerateFiles(runtimeRoot, "*.cs", SearchOption.AllDirectories)
                .Select(File.ReadAllText));

        Assert.False(File.Exists(Path.Combine(
            appRoot,
            "Input",
            "PlayerMovementController.cs")));
        Assert.False(File.Exists(Path.Combine(
            appRoot,
            "Input",
            "LocalPlayerOutboundController.cs")));
        Assert.DoesNotContain(
            "class PlayerMovementController",
            app,
            StringComparison.Ordinal);
        Assert.DoesNotContain(
            "class LocalPlayerOutboundController",
            app,
            StringComparison.Ordinal);
        Assert.Empty(Regex.Matches(app, @"\bbool\s+_autoRunActive\b"));
        Assert.Empty(Regex.Matches(
            app,
            @"RuntimeLocalPlayerMovementState\s+\w+\s*=\s*new\s*\(")
            .Cast<Match>());
        Assert.Single(Regex.Matches(
            runtime,
            @"new\s+RuntimeLocalPlayerMovementState\s*\(")
            .Cast<Match>());
        Assert.DoesNotContain(
            "ACDREAM_RUN_SKILL",
            runtime,
            StringComparison.Ordinal);
        Assert.DoesNotContain(
            "ACDREAM_JUMP_SKILL",
            runtime,
            StringComparison.Ordinal);
    }

    [Fact]
    public void GraphicalInputRuntimeViewsAndShutdownBorrowTheExactOwner()
    {
        string root = FindRepositoryRoot();
        string gameWindow = ReadAppSource(root, "Rendering", "GameWindow.cs");
        string input = ReadAppSource(
            root,
            "Input",
            "DispatcherMovementInputSource.cs");
        string adapter = ReadAppSource(
            root,
            "Runtime",
            "CurrentGameRuntimeAdapter.cs");
        string commands = ReadAppSource(
            root,
            "Runtime",
            "CurrentGameRuntimeCommandAdapter.cs");
        string lifetime = ReadAppSource(
            root,
            "Rendering",
            "GameWindowLifetime.cs");

        Assert.Contains(
            "RuntimeLocalPlayerMovementState _playerControllerSlot =>",
            gameWindow,
            StringComparison.Ordinal);
        Assert.Contains(
            "_runtime.MovementOwner;",
            gameWindow,
            StringComparison.Ordinal);
        Assert.Contains(
            "new AcDream.App.Input.DispatcherMovementInputSource(",
            gameWindow,
            StringComparison.Ordinal);
        Assert.Contains(
            "_playerControllerSlot,",
            gameWindow,
            StringComparison.Ordinal);
        Assert.Contains(
            "RuntimeLocalPlayerMovementState movement,",
            input,
            StringComparison.Ordinal);
        Assert.Contains("_movement.AutoRunActive", input, StringComparison.Ordinal);
        Assert.Contains(
            "private readonly GameRuntime _runtime;",
            adapter,
            StringComparison.Ordinal);
        Assert.Contains("_movement.Execute(command)", commands, StringComparison.Ordinal);
        Assert.Contains(
            "GameRuntime Runtime",
            lifetime,
            StringComparison.Ordinal);
        Assert.Contains(
            "\"game runtime root\"",
            lifetime,
            StringComparison.Ordinal);
    }

    private static string ReadAppSource(string root, params string[] relative) =>
        File.ReadAllText(Path.Combine(
            [root, "src", "AcDream.App", .. relative]));

    private static string FindRepositoryRoot()
    {
        var current = new DirectoryInfo(AppContext.BaseDirectory);
        while (current is not null)
        {
            if (File.Exists(Path.Combine(current.FullName, "AcDream.slnx")))
                return current.FullName;
            current = current.Parent;
        }

        throw new DirectoryNotFoundException("AcDream.slnx was not found.");
    }
}