using System;
using System.ServiceModel;

namespace WCFSample
{
  [ServiceContract]
  public interface IServiceContract
  {
    [OperationContract]
    void StartOnServer(string[] args);
  }

  public class Service: IServiceContract
  {
    public void StartOnServer(string[] args)
    {
      Console.WriteLine(string.Join(",", args));
    }
  }

  class Program
  {
    static void Main(string[] args)
    {
      try
      {
        ServerStart(@"net.pipe://127.0.0.1/wtfService");
      }
      catch (AddressAlreadyInUseException)
      {
        try
        {
          ClientStart(@"net.pipe://127.0.0.1/wtfService");
        }
        catch (Exception ex)
        {
          Console.WriteLine(ex);
          Console.ReadKey();
        }
      }
    }

    private static void ServerStart(string channelUri)
    {
      ServiceHost host = new ServiceHost(typeof(Service), new Uri(channelUri));
      try
      {
        host.AddServiceEndpoint(typeof(IServiceContract),
          new NetNamedPipeBinding(NetNamedPipeSecurityMode.Transport),
          new Uri(channelUri));
        host.Open();

        Console.WriteLine("Service is ready, press any key to terminate.");
        Console.ReadKey();
        // ((Service) as Service).LaucnhStartUpWindow();
      }
      catch (CommunicationException ex)
      {
        // Console.WriteLine(ex);
        Console.WriteLine("Client starting...");
        host.Abort();
        throw;
      }
    }

    private static void ClientStart(string channelUri)
    {
      ChannelFactory<IServiceContract> factory =
        new ChannelFactory<IServiceContract>
            (new NetNamedPipeBinding(), new EndpointAddress(channelUri));
      IServiceContract proxy = factory.CreateChannel();

      try
      {
        //signal server that a new instance is selected
        proxy.StartOnServer(new[] { "Hello", "world" });
      }
      catch (EndpointNotFoundException ex)
      {
        Console.WriteLine(ex);
        //return false to indicate this instance is first instance
        // return false;
      }
    }
  }
}