using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Net;
using System.Net.Sockets;

namespace KnockKnock.Lib
{
	public class Proxy
	{
		public delegate void ProxyEvent(Proxy sender);

		public event ProxyEvent Active;
		public event ProxyEvent Idle;

		Listener listener;
		Upstream upstream;
		List<ConnectionPool> connections;


		public Proxy(IPEndPoint listener, IPEndPoint upstream)
		{
			this.listener = new Listener(listener.Port);
			this.upstream = new Upstream(upstream.Address, upstream.Port);
			this.connections = new List<ConnectionPool>();
		}

		public void Start()
		{
			this.listener.Connected += Listener_Connected;
			this.listener.Start();
		}

		public void Stop()
		{
			foreach (ConnectionPool p in connections)
			{
				p.Close();
			}
			connections.Clear();
		}

		private void Listener_Connected(Listener sender, Socket client_socket)
		{
			if (this.connections.Count == 0 && this.Active != null)
			{
				this.Active(this);
			}
			Socket upstream_socket = this.upstream.Connect();

			Connection client_conn = new Connection(client_socket);
			Connection upstream_conn = new Connection(upstream_socket);

			ConnectionPool cp = new ConnectionPool();
			cp.AddConnection(client_conn);
			cp.AddConnection(upstream_conn);
			cp.Closed += Connection_Closed;
			cp.Open();
		}

		private void Connection_Closed(ConnectionPool sender)
		{
			connections.Remove(sender);
			if (connections.Count == 0 && this.Idle != null)
			{
				this.Idle(this);
			}
		}
	}
}