using System;

public class Program

{

    public static void Main()

    {

        Page p1 = new() 

        {

            Open = new(2024, 12, 12),

            Close = new(2024, 12, 14)

        };

        // never close

        Page p2 = new() 

        {

            Open = new(2024, 12, 12),

            Close = null

        };

        // open immediately

        Page p3 = new() 

        {

            Open = null,

            Close = new(2024, 12, 14)

        };

        // permanently open

        Page p4 = new() 

        {

            Open = null,

            Close = null

        };

        Console.WriteLine($"p1 status: {p1.Status}");

        Console.WriteLine($"p2 status: {p2.Status}");

        Console.WriteLine($"p3 status: {p3.Status}");

        Console.WriteLine($"p4 status: {p4.Status}");

    }

}

​

public class Page

{

    public DateTime? Open {get;set;}

    public DateTime? Close {get;set;}

    public PageStatus Status

    {

        get

        {

            DateTime now = new(2024, 12, 12);

            if (Close <= Open)

            {

                throw new Exception("Could not provide page status: Close must be after Open");

            }

            if (Open.HasValue)

            {

                if (now < Open.Value)

                {

                    return PageStatus.Scheduled;

                }

​

                if (!Close.HasValue || now < Close.Value)

                {

                    return PageStatus.Open;

                }

​

                return PageStatus.Closed;

            }

            if (!Close.HasValue || now < Close.Value)

            {

                return PageStatus.Open;

            }

            return PageStatus.Closed;

        }

    }

}

​

public enum PageStatus 

{

    Scheduled,

    Open,

    Closed

}