using System;

using System.Collections.Generic;

using Newtonsoft.Json;

public class CompassFunction

{

    public static void Main()

    {

        CompassFunction cf = new CompassFunction();

        cf.Run("{}");

    }

    public string Run(string input)

    {

        string jsontest = "{ \"PortCruiseInfo\": [{ \"SYSTEMCRUISE\": \"3041263\",\"CRUISESTARTDATE\": \"202304220000\",\"CRUISEENDDATE\": \"202304290000\" }, { \"SYSTEMCRUISE\": \"3041283\",\"CRUISESTARTDATE\": \"202304290000\",\"CRUISEENDDATE\": \"202305040000\" }] }";

        //dynamic parsedObj = JsonConvert.DeserializeObject<dynamic>(input);

        dynamic parsedObj = JsonConvert.DeserializeObject<dynamic>(jsontest);

        foreach (var sailing in parsedObj.PortCruiseInfo)

        {

            Console.WriteLine(sailing.GetType());

            string cruiseStartDate = sailing.CRUISESTARTDATE;

            string cruiseEndDate = sailing.CRUISEENDDATE;

            var parsedStartDate = ParseTimestamp(cruiseStartDate);

            var parsedEndDate = ParseTimestamp(cruiseEndDate);

            sailing.Add("startDateISO",parsedStartDate);

            sailing.Add("endDateISO",parsedEndDate);

            Console.Write(sailing);

        }

        string updatedJson = JsonConvert.SerializeObject(parsedObj);

​

        return updatedJson;

    }

    private DateTime ParseTimestamp(string timestamp)

    {

        string year = timestamp.Substring(0, 4);

        string month = timestamp.Substring(4, 2);

        string day = timestamp.Substring(6, 2);

        var parsedDt = DateTime.Parse($"{year}-{month}-{day}");

        return parsedDt;

    }

}