task31

using System;
using System.Collections.Generic;
using System.Threading;

public class Program
{
    public static void Main()
    {
        Station station = new Station();

        bool isWork = true;
        ConsoleKey key;
        ConsoleKey exitKey = ConsoleKey.Q;
        int sleepTime = 500;

        while (isWork)
        {
            station.Update();
            if (Console.KeyAvailable)
            {
                key = Console.ReadKey(true).Key;
                if (key == exitKey)
                    isWork = false;
            }
            Thread.Sleep(sleepTime);
        }
    }
}

public class Station
{
    private Train _train;
    private Random _random;
    private int timeStay;
    private int timeArrive;
    bool isArrived;

    private static readonly string[] RoutesFrom = {
        "Minsk",
        "Vitebsk",
        "Mogilev",
        "Brest",
        "Grodno"
    };

    private static readonly string[] RoutesTo =
    {
        "Pinsk",
        "Molodechno",
        "Orsha",
        "Poltsk",
        "Novopolotsk"
    };
    private const int PassengersMaxAmount = 1000;
    private const int PassengersMinAmount = 3;
    private const int WaitTimeArrive = 100;
    private const int WaitTimeStay = 50;

    public Station()
    {
        _train = null;
        _random = new Random();
    }

    public void Showroute()
    {
        Console.Clear();
        if (isArrived)
            Console.WriteLine($"Time to stay : {WaitTimeStay - timeStay}");
        else
            Console.WriteLine($"Time to arrive : {WaitTimeArrive - timeArrive}");

        if (_train != null)
            Console.WriteLine(_train);
        else
            Console.WriteLine("Train hasn't arrived yet.");
    }

    public void Update()
    {
        if (isArrived)
        {
            if (timeStay >= WaitTimeStay)
            {
                isArrived = false;
                _train = null;
                timeStay = 0;
                timeArrive = 0;
            }
            else
            {
                ++timeStay;
            }
        }
        else
        {
            if (timeArrive >= WaitTimeArrive)
            {
                isArrived = true;
                CreateRoute();
                timeStay = 0;
                timeArrive = 0;
            }
            else
            {
                ++timeArrive;
            }
        }

        Showroute();
    }

    private void CreateRoute()
    {
        string routeFrom = RoutesFrom[_random.Next(RoutesFrom.Length)];
        string routeTo = RoutesTo[_random.Next(RoutesTo.Length)];
        int passengersAmount = _random.Next(PassengersMinAmount, PassengersMaxAmount);

        _train = new Train(routeFrom, routeTo, passengersAmount);
    }
}

public class Train
{
    private List<Carriage> _carriages;

    public string RouteFrom { get; private set; }
    public string RouteTo { get; private set; }
    public int PassengersAmount { get; private set; }

    public Train(string routeFrom, string routeTo, int passengersAmount)
    {
        RouteFrom = routeFrom;
        RouteTo = routeTo;
        PassengersAmount = passengersAmount;
        _carriages = new List<Carriage>();
        CreateCarriages();
    }

    public override string ToString()
    {
        string resultString = "";
        resultString += "Route From " + RouteFrom + " To " + RouteTo + "\n";
        resultString += "Amount of passengers: " + PassengersAmount + "\n";
        resultString += "Amount of carriges: " + _carriages.Count + "\n";
        foreach (Carriage carriage in _carriages)
        {
            if (carriage == Carriage.Large)
                resultString += "Large + ";
            else if (carriage == Carriage.Middle)
                resultString += "Large + ";
            else if (carriage == Carriage.Small)
                resultString += "Small + ";
        }
        resultString += "\n\n";

        return resultString;
    }

    private void FillCarriages(Carriage carriageType, ref int passengersAmount)
    {
        int carriagesAmount = passengersAmount / (int) carriageType;
        passengersAmount %= (int) carriageType;

        for (int i = 0; i < carriagesAmount; ++i)
            _carriages.Add(carriageType);
    }

    private void CreateCarriages()
    {
        int passengersAmount = PassengersAmount;

        FillCarriages(Carriage.Large, ref passengersAmount);
        FillCarriages(Carriage.Middle, ref passengersAmount);

        if (passengersAmount < (int) Carriage.Small)
            passengersAmount = (int) Carriage.Small;

        FillCarriages(Carriage.Small, ref passengersAmount);
    }
}

public enum Carriage : int
{
    Small = 5,
    Middle = 10,
    Large = 15
}