namespace CSLight
{
    public class Program
    {
        static void Main(string[] args)
        {
            const string AddDossierCommand = "1";
            const string ShowAllDossierCommand = "2";
            const string SearchLastnameCommand = "3";
            const string DeleteDossierCommand = "4";
            const string ExitProgrammCommand = "5";

            string[] listEmployees = new string[0];
            string[] positions = new string[0];
            bool isRunning = true;

            while (isRunning)
            {
                Console.WriteLine(
                $"{AddDossierCommand})Добавить досье\n" +
                $"{ShowAllDossierCommand})Вывести все досье\n" +
                $"{SearchLastnameCommand})Поиск по фамилии\n" +
                $"{DeleteDossierCommand})Удалить досье\n" +
                $"{ExitProgrammCommand})Выход из программы\n");

                switch (Console.ReadLine())
                {
                    case AddDossierCommand:
                        AddDossier(ref listEmployees, ref positions);
                        break;

                    case ShowAllDossierCommand:
                        ShowAllDossier(listEmployees, positions);
                        break;

                    case SearchLastnameCommand:
                        SearchLastname(listEmployees);
                        break;

                    case DeleteDossierCommand:
                        DeleteDossier(ref listEmployees, ref positions);
                        break;

                    case ExitProgrammCommand:
                        isRunning = false;
                        break;
                }

            }

        }

        static void AddDossier(ref string[] listEmployees, ref string[] positions)
        {
            Console.WriteLine("Введите ФИО сотрудинка через пробел.");
            string fullName = Console.ReadLine();
            Console.WriteLine("Введите должность сотрудинка через пробел.");
            string post = Console.ReadLine();

            listEmployees = ExpandArray(listEmployees, fullName);
            positions = ExpandArray(positions, post);
        }

        static void ShowAllDossier(string[] listEmployees, string[] positions)
        {
            if (listEmployees.Length == 0)
            {
                Console.WriteLine("Досье отсутствуют.");
                return;
            }

            for (int i = 0; i < listEmployees.Length; i++)
            {
                Console.WriteLine($"{i + 1}){listEmployees[i]} - {positions[i]}");
            }

            Console.ReadKey();
        }

        static void SearchLastname(string[] array)
        {
            bool isSearch = false;

            Console.WriteLine("Введите нужную фамилию для поиска");
            string lastName = Console.ReadLine();

            for (int i = 0; i < array.Length; i++)
            {
                char space = ' ';
                string[] surnames = array[i].Split(space);

                if (lastName.ToLower() == surnames[0].ToLower())
                {
                    Console.WriteLine(array[i]);

                    isSearch = true;
                }
            }

            if (isSearch == false)
            {
                Console.WriteLine($"Сотрудники с фамилией '{lastName}' не найдены.");
            }
        }

        static void DeleteDossier(ref string[] listEmployees, ref string[] positions)
        {
            bool isRunning = true;

            ShowAllDossier(listEmployees, positions);

            Console.WriteLine("Введите номер досье которое хотите удалить.");
            int number = ReadInt();

            if (number > listEmployees.Length)
            {
                isRunning = false;
            }

            if (isRunning == true)
            {
                listEmployees = DeleteArrayElement(listEmployees, number);
                positions = DeleteArrayElement(positions, number);
            }
            else
            {
                Console.WriteLine("Такого индекса нет.");
            }
        }

        static string[] ExpandArray(string[] array, string word)
        {
            string[] temporaryArray = new string[array.Length + 1];

            for (int i = 0; i < array.Length; i++)
            {
                temporaryArray[i] = array[i];
            }

            temporaryArray[temporaryArray.Length - 1] = word;

            array = temporaryArray;

            return array;
        }

        static string[] DeleteArrayElement(string[] array, int number)
        {
            string[] temporaryArray = new string[array.Length - 1];

                for (int i = 0; i < (number - 1); i++)
                {
                    temporaryArray[i] = array[i];
                }

                for (int i = (number - 1); i < (temporaryArray.Length); i++)
                {
                    temporaryArray[i] = array[i + 1];
                }

                array = temporaryArray;

                return array;
        }

        static int ReadInt()
        {
            int number = 0;

            while (int.TryParse(Console.ReadLine(), out number) == false)
            {
                Console.WriteLine("Это не число.");
            }

            return number;
        }
    }
}