using System;

public class Program

{

    public static void Main()

    {

        Console.WriteLine("DateTime1");

        DateTime startDate = DateTime.MinValue;

        Console.WriteLine();

        Console.WriteLine();

        Console.WriteLine("***** TEST CASE # 1: Start Date is on Monday *****");

        startDate = new DateTime(2024, 6, 3);

        CalculateTargetDate(startDate, DayOfWeek.Monday);

        CalculateTargetDate(startDate, DayOfWeek.Tuesday);

        CalculateTargetDate(startDate, DayOfWeek.Wednesday);

        CalculateTargetDate(startDate, DayOfWeek.Thursday);

        CalculateTargetDate(startDate, DayOfWeek.Friday);

        CalculateTargetDate(startDate, DayOfWeek.Saturday);

        CalculateTargetDate(startDate, DayOfWeek.Sunday);

        Console.WriteLine();

        Console.WriteLine();

        Console.WriteLine("***** TEST CASE # 2: Start Date is on Tuesday *****");

        startDate = new DateTime(2024, 6, 4);

        CalculateTargetDate(startDate, DayOfWeek.Monday);

        CalculateTargetDate(startDate, DayOfWeek.Tuesday);

        CalculateTargetDate(startDate, DayOfWeek.Wednesday);

        CalculateTargetDate(startDate, DayOfWeek.Thursday);

        CalculateTargetDate(startDate, DayOfWeek.Friday);

        CalculateTargetDate(startDate, DayOfWeek.Saturday);

        CalculateTargetDate(startDate, DayOfWeek.Sunday);

        Console.WriteLine();

        Console.WriteLine();

        Console.WriteLine("***** TEST CASE # 3: Start Date is on Wednesday *****");

        startDate = new DateTime(2024, 6, 5);

        CalculateTargetDate(startDate, DayOfWeek.Monday);

        CalculateTargetDate(startDate, DayOfWeek.Tuesday);

        CalculateTargetDate(startDate, DayOfWeek.Wednesday);

        CalculateTargetDate(startDate, DayOfWeek.Thursday);

        CalculateTargetDate(startDate, DayOfWeek.Friday);

        CalculateTargetDate(startDate, DayOfWeek.Saturday);

        CalculateTargetDate(startDate, DayOfWeek.Sunday);

        Console.WriteLine();

        Console.WriteLine();

        Console.WriteLine("***** TEST CASE # 4: Start Date is on Thursday *****");

        startDate = new DateTime(2024, 6, 6);

        CalculateTargetDate(startDate, DayOfWeek.Monday);

        CalculateTargetDate(startDate, DayOfWeek.Tuesday);

        CalculateTargetDate(startDate, DayOfWeek.Wednesday);

        CalculateTargetDate(startDate, DayOfWeek.Thursday);

        CalculateTargetDate(startDate, DayOfWeek.Friday);

        CalculateTargetDate(startDate, DayOfWeek.Saturday);

        CalculateTargetDate(startDate, DayOfWeek.Sunday);

        Console.WriteLine();

        Console.WriteLine();

        Console.WriteLine("***** TEST CASE # 5: Start Date is on Friday *****");

        startDate = new DateTime(2024, 6, 7);

        CalculateTargetDate(startDate, DayOfWeek.Monday);

        CalculateTargetDate(startDate, DayOfWeek.Tuesday);

        CalculateTargetDate(startDate, DayOfWeek.Wednesday);

        CalculateTargetDate(startDate, DayOfWeek.Thursday);

        CalculateTargetDate(startDate, DayOfWeek.Friday);

        CalculateTargetDate(startDate, DayOfWeek.Saturday);

        CalculateTargetDate(startDate, DayOfWeek.Sunday);

        Console.WriteLine();

        Console.WriteLine();

        Console.WriteLine("***** TEST CASE # 6: Start Date is on Saturday *****");

        startDate = new DateTime(2024, 6, 8);

        CalculateTargetDate(startDate, DayOfWeek.Monday);

        CalculateTargetDate(startDate, DayOfWeek.Tuesday);

        CalculateTargetDate(startDate, DayOfWeek.Wednesday);

        CalculateTargetDate(startDate, DayOfWeek.Thursday);

        CalculateTargetDate(startDate, DayOfWeek.Friday);

        CalculateTargetDate(startDate, DayOfWeek.Saturday);

        CalculateTargetDate(startDate, DayOfWeek.Sunday);

        Console.WriteLine();

        Console.WriteLine();

        Console.WriteLine("***** TEST CASE # 7: Start Date is on Sunday *****");

        startDate = new DateTime(2024, 6, 9);

        CalculateTargetDate(startDate, DayOfWeek.Monday);

        CalculateTargetDate(startDate, DayOfWeek.Tuesday);

        CalculateTargetDate(startDate, DayOfWeek.Wednesday);

        CalculateTargetDate(startDate, DayOfWeek.Thursday);

        CalculateTargetDate(startDate, DayOfWeek.Friday);

        CalculateTargetDate(startDate, DayOfWeek.Saturday);

        CalculateTargetDate(startDate, DayOfWeek.Sunday);

    }

    private static void CalculateTargetDate(DateTime startDate, DayOfWeek targetDateDayOfWeek)

    {

        Console.WriteLine("--->");

        Console.WriteLine("Arguments: startDate={0}, targetDateDayOfWeek={1}", startDate, targetDateDayOfWeek);

        Console.WriteLine("startDate.DayOfWeek={0}", startDate.DayOfWeek);

        int diff = (7 + (startDate.DayOfWeek - targetDateDayOfWeek)) % 7;

        Console.WriteLine("diff={0}", diff);

        //DateTime targetDate = startDate.AddDays((-1 * diff) + 7).Date;

        //Console.WriteLine("targetDate={0}", targetDate);

        DateTime targetDate = startDate.AddDays((-1 * diff) + (diff == 0 ? 0 : 7)).Date;

        Console.WriteLine("targetDate={0}", targetDate);

    }

}