using System;

using System.Text;

using System.Security.Cryptography; 

using Newtonsoft.Json;

using System.Linq;

public class Program

{

    public static void Main()

    {

        Console.WriteLine("Hello World2");

        var card = new CardToRegisterDto() {

             CreationDate = "2023-02-09T00:00:00+00:00",

      ExpiryDate = "2031-02-09T00:00:00+00:00",

      Pan = "0000000000000203059",

      Certificate = "DCBB4AF2BCBD76B8C1D40906101FF588934A1080A75E586BACB63E643C840825616162F4208B87090C16352DC299437B3D24B958FBA3B922FE0A24316B215FA5B2395B75D5EC4984FFFF4532C0DD43C4999049BBEDCCF636CF02C7A5FD06415B198EFD580DF8A9941654A247C0E62A38F692B564430E778E955308B4FDB4BE8566951C0935E70DDF59EFB6A904C49FE1",

      Checksum  ="DD1D54EB5921B70029C963E8252B45740B2304CFD5032CF08A39AD6A1F8B3AC8",

      Uid = "13C7CAA8A226EF",

        ManufacturerState = "MANUFACTURED",

      Cvv = "000",

      BoxNumber =  "12",

      SerialNumber= "2"

        };

        var checksum = Calc(card);

        Console.WriteLine(checksum);

    }

     public static string Calc(CardToRegisterDto card)

        {

            var json = JsonConvert.SerializeObject(card);

​

            System.Collections.Generic.Dictionary<string, string> dict = JsonConvert.DeserializeObject<System.Collections.Generic.Dictionary<string, string>>(json);

​

            // Remove checksum field

            //We have to use this lookup becase then name in DTO

            //maybe diff from the on in the dict

            var lookup = dict!.FirstOrDefault(x => x.Key.Equals(nameof(CardToRegisterDto.Checksum).ToLower(), StringComparison.OrdinalIgnoreCase));

            if (lookup.Key != null)

            {

                Console.WriteLine(lookup.Key);

                dict!.Remove(lookup.Key);

            }

​

            // Values sorted by their corresponding keys in alphabetical order

            var orderedValues = dict!

                .Where(element => element.Value != null)

                .OrderBy(element => element.Key)

                .Select(element => element.Value);

​

            var str = string.Join(',', orderedValues);

            Console.WriteLine(str);

            // Compute

            var hex = Generate(str);

​

            return hex;

        }

     public static string Generate(string str)

        {

            using var hash = SHA256.Create();

            var byteArray = hash.ComputeHash(Encoding.UTF8.GetBytes(str));

            var hex = Convert.ToHexString(byteArray);

            return hex;

        }

​

    public class CardToRegisterDto

{

    /// <summary>

    /// Datetime when the card was manufactured in ISO8601

    /// </summary>

    public string CreationDate { get; set; }

​

    /// <summary>

    /// Datetime when the card expires in ISO8601

    /// </summary>

    public string ExpiryDate { get; set; }

​

    /// <summary>

    /// The cards PAN

    /// </summary>

    public string? Pan { get; set; }

​

    /// <summary>

    /// Public certificate on the card in HEX

    /// </summary>

    public string? Certificate { get; set; }

​

    /// <summary>

    /// SHA256 checksum of all fields in 

    /// alphabetical order on a card joined by ','

    /// </summary>

    public string? Checksum { get; set; }

​

    /// <summary>

    /// The unique identifier for this card

    /// </summary>

    public string? Uid { get; set; }

​

    /// <summary>

    /// Current state of the card

    /// </summary>

    public string ManufacturerState { get; set; } = "Manufactured";

​

    /// <summary>

    /// Controlnumber for cardnumber (three digit)

    /// </summary>

    public string? Cvv { get; set; }

​

    /// <summary>

    /// The number printed on the box with cards

    /// Also applied on the card

    /// </summary>

    public string? BoxNumber { get; set; }

​

    /// <summary>

    /// The number of the positon of the card

    /// in the box, also applied on the card

    /// </summary>

    public string? SerialNumber { get; set; }

    }

}