using System;

using System.Collections.Generic;

using System.Linq;

using System.Threading;

public class Program

{

    public static void Main()

    {

        /*scenario when all the directories are available*/

        Console.WriteLine("Start Of First Test");

        CheckCanWriteOutputFolders(new List<string>{"DirectoryOne","DirectoryTwo"});

        Console.WriteLine("End Of First Test \n");

        /*scenario when one the directory fails*/

        Console.WriteLine("Start Of Second Test");

        CheckCanWriteOutputFolders(new List<string>{"DirectoryOne1","DirectoryTwo"});

        Console.WriteLine("End Of Second Test \n");

        /*scenario when all directories failing*/

        Console.WriteLine("Start Of Third Test");

        CheckCanWriteOutputFolders(new List<string>{"DirectoryOne1","Directory2"});

        Console.WriteLine("End Of Third Test \n");

​

    }

            /// <summary>

        /// To check and throw error if can't access and write to the folders

        /// </summary>

        private static void CheckCanWriteOutputFolders(List<string> directoryList)

        {

            List<string> failedDirectories;

            var loopCount = 0;

            const int maximumLoopExecutionTimes = 3; // Todo this should be loaded from configuration system

            const int millisecondsToSleepBeforeTryAgain = 1000; // Todo this should be loaded from configuration system

            /*Following is a loop to try few times before throwing exception*/

            do

            {

                Console.WriteLine("Before-Sleep, loopCount:"+loopCount);

                /*Skipping the first time and sleep for one second before trying again*/

                if (loopCount != 0)

                {

                    Console.WriteLine("Inside-Sleep, loopCount:"+loopCount);

                    Thread.Sleep(millisecondsToSleepBeforeTryAgain);

                }

                loopCount++;

                failedDirectories = GetAccessFailingDirectoryList(directoryList);

            } while (failedDirectories.Any() && (loopCount < maximumLoopExecutionTimes));

            Console.WriteLine("After the Loop, loopCount:"+loopCount);

            foreach(string t in failedDirectories)

            {

                Console.WriteLine(t);

            }

​

            if (failedDirectories.Any())

                Console.WriteLine("Exception Thrown here:"+string.Join("; ", failedDirectories.ToArray()));

                /*throw new InvalidOperationException(

                    string.Format("The application can not write files to the following locations: {0}",

                        string.Join("; ", failedDirectories.ToArray())));*/

        }

​

        /// <summary>

        /// Get list of directories that failed to write on to

        /// </summary>

        /// <returns></returns>

        private static List<string> GetAccessFailingDirectoryList(IEnumerable<string> directoryList)

        {

            return directoryList.Where(directory => CheckCanWriteDirectory(directory)).ToList();

        }

        public static bool CheckCanWriteDirectory(string directory)

        {

​

            return directory.Any(char.IsDigit);//For Testing- if any numeriacal value found on string, it will send true

        }

}