// Adaptee
    class OldElectricitySystem
    {
        public string MatchThinSocket()
        {
            return "220V";
        }
    }
    // known interface in our code
    interface INewElectricitySystem
    {
        string MatchWideSocket();
    }
    class NewElectricitySystem : INewElectricitySystem
    {
        public string MatchWideSocket()
        {
            return "220V";
        }
    }
    // Adapter
    class Adapter : INewElectricitySystem
    {
        private readonly OldElectricitySystem _adaptee;

        public Adapter(OldElectricitySystem adaptee)
        {
            _adaptee = adaptee;
        }

        // All the magic lives here
        // in our adapter we translate from
        // what we (code) cannot use straightway into what we can
        public string MatchWideSocket()
        {
            return _adaptee.MatchThinSocket();
        }
    }

    class ElectricityConsumer
    {
        // Charging device can be used only with new system
        public static void ChargeNotebook(INewElectricitySystem electricitySystem)
        {
            Console.WriteLine(electricitySystem.MatchWideSocket());
        }
    }

    public class AdapterDemo
    {
        public static void Run()
        {
            // We can easily operate with our new system
            var newElectricitySystem = new NewElectricitySystem();
            ElectricityConsumer.ChargeNotebook(newElectricitySystem);

            // We have to adapt to old system using adapter
            var oldElectricitySystem = new OldElectricitySystem();
            var adapter = new Adapter(oldElectricitySystem);
            ElectricityConsumer.ChargeNotebook(adapter);
        }
    }

    internal class SkiRent
    {
        public int RentBoots(int feetSize, int skierLevel)
        {
            return 20;
        }
        public int RentSki(int weight, int skierLevel)
        {
            return 40;
        }
        public int RentPole(int height)
        {
            return 5;
        }
    }

    internal class SkiResortTicketSystem
    {
        public int BuyOneDayTicket()
        {
            return 120;
        }
        public int BuyHalfDayTicket()
        {
            return 60;
        }
    }

    internal class HotelBookingSystem
    {
        public int BookRoom(int roomQuality)
        {
            switch (roomQuality)
            {
                case 3:
                    return 250;
                case 4:
                    return 500;
                case 5:
                    return 900;
                default:
                    throw new ArgumentException("roomQuality should be in range [3;5]","roomQuality");
            }
        }
    }

    public class SkiResortFacade
    {
        private SkiRent _skiRent = new SkiRent();
        private SkiResortTicketSystem _skiResortTicketSystem = new SkiResortTicketSystem();
        private HotelBookingSystem _hotelBookingSystem = new HotelBookingSystem();

        public int HaveGoodOneDayRest(int height, int weight, int feetSize, int skierLevel, int roomQuality)
        {
            int skiPrice = _skiRent.RentSki(weight, skierLevel);
            int skiBootsPrice = _skiRent.RentBoots(feetSize, skierLevel);
            int polePrice = _skiRent.RentPole(height);
            int oneDayTicketPrice = _skiResortTicketSystem.BuyOneDayTicket();
            int hotelPrice = _hotelBookingSystem.BookRoom(roomQuality);

            return skiPrice + skiBootsPrice + polePrice + oneDayTicketPrice + hotelPrice;
        }

        public int HaveRestWithOwnSkis()
        {
            int oneDayTicketPrice = _skiResortTicketSystem.BuyOneDayTicket();
            return oneDayTicketPrice;
        }
    }

    public class FacadeDemo
    {
        public static void Run()
        {
            var skiResortFacade = new SkiResortFacade();

            int weekendRestPrice = skiResortFacade.HaveGoodOneDayRest(175, 60, 42, 2, 3);

            Console.WriteLine("Price: {0}", weekendRestPrice);
        }
    }