using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using Konscious.Security.Cryptography;
using System.Security.Cryptography;
using System.Diagnostics;

namespace Argon2
{
    class Program
    {
        static void Main(string[] args)
        {
            Run();
        }

        private static byte[] CreateSalt()
        {
            var buffer = new byte[64];
            var rng = new RNGCryptoServiceProvider();
            rng.GetBytes(buffer);
            return buffer;
        }

        private static byte[] HashPassword(string password, byte[] salt)
        {
            var argon2 = new Argon2id(Encoding.UTF8.GetBytes(password));

            argon2.Salt = salt;
            argon2.DegreeOfParallelism = 8; // four cores
            argon2.Iterations = 4;
            argon2.MemorySize = 1024 * 1024; //1GB

            return argon2.GetBytes(64);
        }

        private static bool VerifyHash(string password, byte[] salt, byte[] hash)
        {
            var newHash = HashPassword(password, salt);
            return hash.SequenceEqual(newHash);
        }

        public static void Run()
        {
            var password = "SutPikOgDø123!@";
            var stopwatch = Stopwatch.StartNew();

            Console.WriteLine($"Creating hash for password '{ password }' .");

            var salt = CreateSalt();
            Console.WriteLine($"Using salt '{ Convert.ToBase64String(salt) }' .");

            var hash = HashPassword(password, salt);
            Console.WriteLine($"Hash is '{ Convert.ToBase64String(hash) }' .");

            stopwatch.Stop();
            Console.WriteLine($" Process took { stopwatch.ElapsedMilliseconds / 1024.0 } s");

            stopwatch = Stopwatch.StartNew();
            Console.WriteLine($"Verifying hash....");

            var success = VerifyHash(password, salt, hash);
            Console.WriteLine(success ? "Success!" : "Failure!");

            stopwatch.Stop();
            Console.WriteLine($"Process took { stopwatch.ElapsedMilliseconds / 1024.0 } s");

            Console.ReadLine();
        }

    }
}