Nullean.Argh

using Nullean.Argh;
using System.ComponentModel.DataAnnotations;

var app = new ArghApp();

app.UseGlobalOptions<GlobalOptions>();
app.Map<DeployCommands>();
app.MapNamespace<StorageCommands>("storage", ns =>
{
    ns.MapNamespace<BlobCommands>("blob");
});

return await app.RunAsync(args);

public record GlobalOptions(bool Verbose = false);

public static class DeployCommands
{
    /// <summary>Deploy the app to a target environment.</summary>
    /// <param name="environment">Target environment.</param>
    /// <param name="dryRun">Validate only, make no changes.</param>
    /// <param name="port">-p, Service port.</param>
    public static async Task<int> Deploy(
        [Argument] string environment,
        [Range(1, 65535)] int port = 8080,
        bool dryRun = false,
        CancellationToken ct = default)
    {
        Console.WriteLine($"Deploying to {environment}:{port}");
        return 0;
    }
}

/// <summary>Manage cloud storage resources.</summary>
public sealed class StorageCommands
{
    /// <summary>List objects in the bucket.</summary>
    public void List() => Console.WriteLine("listing...");
}

/// <summary>Blob sub-commands.</summary>
public sealed class BlobCommands
{
    /// <summary>Upload a file to storage.</summary>
    /// <param name="path">-p, --path, Local file path.</param>
    public void Upload([Existing] FileInfo path) =>
        Console.WriteLine($"uploading {path.Name}");
}