using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace Bridge
{
    /// <summary>

    /// MainApp startup class for Structural

    /// Bridge Design Pattern.

    /// </summary>
    //Decouple an abstraction from its implementation so that the two can vary independently.
    class MainApp
    {
        /// <summary>

        /// Entry point into console application.

        /// </summary>

        static void Main()
        {
            Abstraction ab = new RefinedAbstraction();

            // Set implementation and call

            ab.Implementor = new ConcreteImplementorA();
            ab.Operation();

            // Change implemention and call

            ab.Implementor = new ConcreteImplementorB();
            ab.Operation();

            // Wait for user

            Console.ReadKey();
        }
    }

    /// <summary>

    /// The 'Abstraction' class

    /// </summary>

    class Abstraction
    {
        protected Implementor implementor;

        // Property

        public Implementor Implementor
        {
            set { implementor = value; }
        }

        public virtual void Operation()
        {
            implementor.Operation();
        }
    }

    /// <summary>

    /// The 'Implementor' abstract class

    /// </summary>

    abstract class Implementor
    {
        public abstract void Operation();
    }

    /// <summary>

    /// The 'RefinedAbstraction' class

    /// </summary>

    class RefinedAbstraction : Abstraction
    {
        public override void Operation()
        {
            implementor.Operation();
        }
    }

    /// <summary>

    /// The 'ConcreteImplementorA' class

    /// </summary>

    class ConcreteImplementorA : Implementor
    {
        public override void Operation()
        {
            Console.WriteLine("ConcreteImplementorA Operation");
        }
    }

    /// <summary>

    /// The 'ConcreteImplementorB' class

    /// </summary>

    class ConcreteImplementorB : Implementor
    {
        public override void Operation()
        {
            Console.WriteLine("ConcreteImplementorB Operation");
        }
    }
}