using System;

​

public class Program

{

    public static void Main()

    {

        DateTime? result = null;

        DateTime fromDateTime = DateTime.Now.AddDays(5);

        bool OccursDay = true;

        int OccursDayCount = 0;

        int OccursEveryWeekCount = 2;

        bool DailyOccursOnce = true;

        TimeSpan DailyOnceOccursAt = new TimeSpan(11, 30, 0);

        //bool DailyOccursOnce = false;

        //double timePassed = 0;

        //int RecursEveryDayCount = 3;

        //TimeSpan DailyOnceOccursAt = new TimeSpan(1, 0, 0);

        //int DailyOccursEveryCount = 1;

        //string DailyOccursEveryUnit = "Minutes";

        //TimeSpan DailyOccursStartingAt = new TimeSpan(2, 30, 0);

        //TimeSpan? DailyOccursEndingAt = new TimeSpan(23, 0, 0);

        DateTime StartDate = DateTime.Now;

        DateTime? EndDate = null;

        DateTime NextStartDateTime = FirstOfMonth(StartDate);

        int count = 0;

        if (fromDateTime > NextStartDateTime)

            NextStartDateTime = FirstOfMonth(fromDateTime);

​

        // Set date of first occurance

        // First possible month

        //while (NextStartDateTime.Date < StartDate.Date || NextStartDateTime.Date < fromDateTime.Date)

        {

                count++;

            // For the Day of the month

            if (OccursDay)

            {

                //if (NextStartDateTime.Date <= new DateTime(NextStartDateTime.Year, NextStartDateTime.Month, OccursDayCount))

                //  NextStartDateTime = new DateTime(NextStartDateTime.Year, NextStartDateTime.Month, OccursDayCount);

            }

            else 

            {

            }

            //NextStartDateTime = NextStartDateTime.AddDays(RecursEveryDayCount).Date;

            if (count > 10000000)

                {

                //  break;

                }

            }

        Console.WriteLine("NextStartDateTime: " + NextStartDateTime);

    }

​

    internal static DateTime FirstOfMonth(DateTime input)

    {

        return new DateTime(input.Year, input.Month, 1);

    }

    internal static DateTime MonthlyWhichWhat(VisSchedule.Occurs_The which, VisSchedule.Occurs_The_Of what, DateTime dateTime)

    {

        dateTime = FirstOfMonth(dateTime);

        return dateTime;

    }

    internal static DateTime MonthlyOccurance(VisSchedule schedule, DateTime dateTime)

    {

        dateTime = FirstOfMonth(dateTime);

        if (schedule.OccursTheOf_Type == VisSchedule.Occurs_The_Of.Monday) 

        {

        }

        else if (schedule.OccursTheOf_Type == VisSchedule.Occurs_The_Of.Tuesday) 

        {

        }

        else if (schedule.OccursTheOf_Type == VisSchedule.Occurs_The_Of.Wednesday) 

        {

        }

        else if (schedule.OccursTheOf_Type == VisSchedule.Occurs_The_Of.Thursday) 

        {

        }

        else if (schedule.OccursTheOf_Type == VisSchedule.Occurs_The_Of.Friday) 

        {

        }

        else if (schedule.OccursTheOf_Type == VisSchedule.Occurs_The_Of.Saturday) 

        {

        }

        else if (schedule.OccursTheOf_Type == VisSchedule.Occurs_The_Of.Sunday) 

        {

        }

        else if (schedule.OccursTheOf_Type == VisSchedule.Occurs_The_Of.day) 

        {

        }

        else if (schedule.OccursTheOf_Type == VisSchedule.Occurs_The_Of.Weekday) 

        {

        }

        else if (schedule.OccursTheOf_Type == VisSchedule.Occurs_The_Of.Weekend_Day) 

        {

        }

        return dateTime;

    }

}

​

 public class VisSchedule

    {

        // Schedule - Main

        public int Id { get; set; }

        public string Name { get; set; }

        public bool Enabled { get; set; }

        public Schedule_Type ScheduleType { get; set; }

        public DateTime? OneTimeOccurance { get; set; }

        // Frequency

        public Frequency ScheduleFrequency { get; set; }

        //public Occurs_Every OccursEvery { get; set; }

        // Frequency - Daily

        public int RecursEveryDayCount { get; set; }

        // Frequency - Weekly

        public int OccursEveryWeekCount { get; set; }

        public bool Sunday { get; set; }

        public bool Monday { get; set; }

        public bool Tuesday { get; set; }

        public bool Wednesday { get; set; }

        public bool Thursday { get; set; }

        public bool Friday { get; set; }

        public bool Saturday { get; set; }

        // Frequency - Monthly

        public bool OccursDay { get; set; }

        public int OccursDayCount { get; set; }

        public int Occurs_DayOfEveryMonth { get; set; }

        public Occurs_The OccursThe_Type { get; set; }

        public Occurs_The_Of OccursTheOf_Type { get; set; }

        public int OccursTheOfEveryMonth { get; set; }

        // Daily Frequency

        public bool DailyOccursOnce { get; set; }

        public TimeSpan DailyOnceOccursAt { get; set; }

        public int DailyOccursEveryCount { get; set; }

        public Occurs_Every DailyOccursEvery_Type { get; set; }

        public TimeSpan DailyOccursStartingAt { get; set; }

        public TimeSpan DailyOccursEndingAt { get; set; }

        // Duration

        public DateTime StartDate { get; set; }

        public bool NoEndDate { get; set; }

        public DateTime? EndDate { get; set; }

        // Enums

        public enum Schedule_Type { Recurring = 0, OneTime = 1 }

        public enum Frequency { Daily = 0, Weekly = 1, Monthly = 2 }

        public enum Occurs_Every { Hours = 0, Minutes = 1, Seconds = 2 }

        public enum Occurs_The { First = 0, Second = 1, Third = 2, Fourth = 3, Last = 4 }

        public enum Occurs_The_Of { Monday = 0, Tuesday = 1, Wednesday = 2, Thursday = 3, Friday = 4, Saturday = 5, Sunday = 6, day = 7, Weekday = 8, Weekend_Day = 9 }

        //public virtual ScheduleInfo Info { get; set; }

    }