The program helps the user to make a train plan. In the upper part of the program, full information about the current flight or its absence is displayed.

Train planer

internal class Program
{
    public static void Main()
    {
        Terminal userInterface = new Terminal();

        userInterface.ShowMainMenu();
    }

    class Train
    {
        private int _seats = 0;
        private bool _status = false;
        private List<Wagon> _wagons = new List<Wagon>();

        public Train() { }

        public Train(int passangersNumber)
        {
            while (_seats < passangersNumber)
            {
                Wagon wagon = new Wagon();
                _seats += wagon.Seats;
                _wagons.Add(wagon);
            }
        }

        public void Depart()
        {
            _status = true;
        }

        public string GetInfo()
        {
            string info = $"Wagons info: ";
            List<string> types = new List<string>();
            List<int> roominess = new List<int>();
            Dictionary<string, int> wagonCounter = new Dictionary<string, int>();

            if (_wagons.Any() == false)
            {
                info += "No info.\n";
            }
            else
            {
                foreach (Wagon wagon in _wagons)
                {
                    if (types.Contains(wagon.Type) == false)
                    {
                        types.Add(wagon.Type);
                        roominess.Add(wagon.Seats);
                        wagonCounter.Add(wagon.Type, 1);
                    }
                    else
                    {
                        wagonCounter[wagon.Type] += 1;
                    }
                }

                for (int i = 0; i < types.Count(); i++)
                {
                    info += $"\n{i + 1}. Type: {types[i]}, seats: {roominess[i]}, count: {wagonCounter[types[i]]}.\n";
                }

                info += $"Total number of seats in train: {_seats}\n";
            }

            info += $"Departure status: {_status}.\n";
            return info;
        }
    }

    class Wagon
    {
        private string[] _types = { "Small", "Big", "VIP" };
        private int[] _roominess = { 10, 20, 4 };

        public Wagon()
        {
            Random random = new Random();
            int value = random.Next(_types.Length - 1);

            Seats = _roominess[value];
            Type = _types[value];
        }

        public int Seats { get; private set; }
        public string Type { get; private set; }
    }

    class Ticket
    {
        private int _maxValue = 10000;
        private Random _random = new Random();

        public Ticket()
        {
            TicketsNumber = -1;
        }

        public Ticket(Path path)
        {
            TicketsNumber = _random.Next(_maxValue);
        }

        public int TicketsNumber { get; private set; }

        public string GetInfo()
        {
            string ticketsInfo = "Tickets sold: ";

            if (TicketsNumber < 0)
                return null;
            else
                ticketsInfo += TicketsNumber < 0 ? "Start sellings first!\n" : $"{TicketsNumber}.\n";

            return ticketsInfo;
        }
    }

    class Path
    {
        private string _departure = string.Empty;
        private string _arrival = string.Empty;

        public Path()
        {

        }

        public Path(string departure, string arrival)
        {
            _departure = departure;
            _arrival = arrival;
        }

        public string GetRoute()
        {
            if (_departure != string.Empty)
            {
                string route = $"Trip: {_departure} - {_arrival}.\n";
                return route;
            }
            else
            {
                return null;
            }
        }
    }

    class Terminal
    {
        private ErrorLogger _error = new ErrorLogger();
        private Path _path = new Path();
        private Ticket _tickets = new Ticket();
        private Train _train = new Train();

        public void ShowMainMenu()
        {
            const int CommandCreatePath = 1;
            const int CommandSellTickets = 2;
            const int CommandCreateTrain = 3;
            const int CommandSendTrain = 4;
            const int CommandExit = 5;

            int command;
            bool isOpen = true;
            string menuText = $"Press {CommandCreatePath} - to create path\n" +
                              $"Press {CommandSellTickets} - to sell tickets\n" +
                              $"Press {CommandCreateTrain} - to create train\n" +
                              $"Press {CommandSendTrain} - to send train\n" +
                              $"Press {CommandExit} - to exit\n";

            while (isOpen)
            {
                TripInfo();
                Console.WriteLine(menuText);

                if (int.TryParse(Console.ReadLine(), out command))
                {
                    switch (command)
                    {
                        case CommandCreatePath:
                            CreatePath();
                            break;

                        case CommandSellTickets:
                            SellTickets();
                            break;

                        case CommandCreateTrain:
                            CreateTrain();
                            break;

                        case CommandSendTrain:
                            SendTrain();
                            break;

                        case CommandExit:
                            isOpen = false;
                            break;

                        default:
                            Console.WriteLine(_error.WrongCommandMessage);
                            break;
                    }
                }
                else
                {
                    Console.WriteLine(_error.ParsingMessage);
                }

                Console.ReadKey(true);
                Console.Clear();
            }
        }

        private void TripInfo()
        {
            string emptyDescription = "No trips prepared\n\n";
            string description;

            description = _path.GetRoute() + _tickets.GetInfo() + _train.GetInfo();

            if (_path.GetRoute() != null)
            {
                Console.WriteLine(description);
            }
            else
            {
                Console.WriteLine(emptyDescription);
            }

        }

        private void SendTrain()
        {
            if (_train.GetInfo().Contains("No info") == false)
            {
                _train.Depart();

                Console.Clear();
                TripInfo();

                _path = new Path();
                _tickets = new Ticket();
                _train = new Train();
            }
            else
            {
                Console.WriteLine(_error.OtherError + "First create train!"); 
            }
        }

        private void CreateTrain()
        {
            if (_tickets.GetInfo() != null)
            {
                _train = new Train(_tickets.TicketsNumber);
            }
            else
            {
                Console.WriteLine(_error.OtherError + "Sell tickets first");
            }
        }

        private void SellTickets()
        {
            if (_path.GetRoute() != null)
            {
                _tickets = new Ticket(_path);
            }
            else
            {
                Console.WriteLine(_error.OtherError + "Add trip first");
            }
        }

        private void CreatePath()
        {
            string departure;
            string arrival;

            Console.Write("Enter departure city: ");
            departure = Console.ReadLine();

            Console.Write("Enter arrival city: ");
            arrival = Console.ReadLine();

            _path = new Path(departure, arrival);
        }
    }

    class ErrorLogger
    {
        public ErrorLogger()
        {
            ParsingMessage = "Error! Enter a number, please.";
            WrongCommandMessage = "Error, there is no such command!";
            OtherError = "Error! ";
        }

        public string ParsingMessage { get; private set; }
        public string WrongCommandMessage { get; private set; }
        public string OtherError { get; private set; }
    }
}