using System.IO;
using ClaudeDo.Installer.Core;

namespace ClaudeDo.Installer.Steps;

public sealed class RegisterAutostartStep : IInstallStep
{
    public const string LegacyTaskName = "ClaudeDoWorker";
    private const string LegacyServiceName = "ClaudeDoWorker";

    public string Name => "Register Autostart";

    public async Task<StepResult> ExecuteAsync(InstallContext ctx, IProgress<string> progress, CancellationToken ct)
    {
        var workerExe = Path.Combine(ctx.InstallDirectory, "worker", "ClaudeDo.Worker.exe");
        if (!File.Exists(workerExe))
            return StepResult.Fail($"Worker executable not found: {workerExe}");

        // Legacy service/task cleanup below runs unconditionally on every install/update/repair,
        // even though it's a no-op once migrated. A cached "already migrated" flag could go stale
        // (e.g. a user re-adds the legacy service) and strand them with it still running; two
        // extra process starts per run is the price for that migration safety net.

        // 1) Migrate away the legacy Windows service if present.
        progress.Report("Checking for legacy worker service...");
        var (queryExit, _) = await ProcessRunner.RunAsync("sc.exe", $"query {LegacyServiceName}", null, progress, ct);
        if (queryExit == 0)
        {
            progress.Report("Removing legacy worker service...");
            await ProcessRunner.RunAsync("sc.exe", $"stop {LegacyServiceName}", null, progress, ct);
            await ProcessRunner.RunAsync("sc.exe", $"delete {LegacyServiceName}", null, progress, ct);
            for (var i = 0; i < 30; i++)
            {
                ct.ThrowIfCancellationRequested();
                var (q, _) = await ProcessRunner.RunAsync("sc.exe", $"query {LegacyServiceName}", null, progress, ct);
                if (q != 0) break;
                await Task.Delay(1000, ct);
            }
        }

        // 2) Migrate away the legacy logon scheduled task if present (best-effort).
        progress.Report("Removing legacy logon task...");
        await ProcessRunner.RunAsync("schtasks.exe", $"/Delete /TN \"{LegacyTaskName}\" /F", null, progress, ct);

        // 3) Register per-user autostart via a Startup-folder shortcut.
        progress.Report("Checking Startup shortcut...");
        try
        {
            var created = AutostartShortcut.Install(AutostartShortcut.DefaultStartupDir, workerExe);
            progress.Report(created ? "Startup shortcut created." : "Startup shortcut already up to date.");
        }
        catch (Exception ex)
        {
            return StepResult.Fail($"Failed to create Startup shortcut: {ex.Message}");
        }

        return StepResult.Ok();
    }
}