using System;
using System.IO;
using System.Security.Cryptography;
using System.Text;

namespace LicenseGenerator.Commands
{
    internal static class SignCommand
    {
        internal static void Execute(InputArgs args)
        {
            if (string.IsNullOrEmpty(args.KeyPath))
            {
                Console.Error.WriteLine("Missing: -key=<path-to-private.key.xml>");
                Environment.Exit(1);
            }
            if (string.IsNullOrEmpty(args.Fingerprint))
            {
                Console.Error.WriteLine("Missing: -fingerprint=<machine-fingerprint>");
                Environment.Exit(1);
            }

            string privateXml = File.ReadAllText(args.KeyPath);
            byte[] data = Encoding.UTF8.GetBytes(args.Fingerprint);

            using (var rsa = new RSACryptoServiceProvider())
            {
                rsa.FromXmlString(privateXml);
                byte[] signature = rsa.SignData(data, new SHA256CryptoServiceProvider());
                string base64 = Convert.ToBase64String(signature);
                File.WriteAllText(args.OutPath, base64);
                Console.WriteLine("License written: " + args.OutPath);
            }
        }
    }
}