/*********************************************************************/
/*                                                                   */
/*                     AgentService Framework                        */
/*                       www.agentservice.it                         */
/*                                                                   */
/* Copyright (C) 2007 l.i.d.o. - DIST, University of Genoa, Italy    */
/* GNU Lesser General Public License                                 */
/*                                                                   */
/* This library is free software; you can redistribute it and/or     */
/* modify it under the terms of the GNU Lesser General Public        */
/* License as published by the Free Software Foundation,             */
/* version 2.1 of the License.                                       */
/*                                                                   */
/* This library is distributed in the hope that it will be useful,   */
/* but WITHOUT ANY WARRANTY; without even the implied warranty of    */
/* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU */
/* Lesser General Public License for more details.                   */
/*                                                                   */
/* You should have received a copy of the GNU Lesser General Public  */
/* License along with this library; if not, write to the             */
/* Free Software Foundation, Inc., 59 Temple Place - Suite 330,      */
/* Boston, MA  02111-1307, USA.                                      */
/*                                                                   */
/*********************************************************************/
using System;
using System.Net;
using System.Collections;
using AgentService.Interop;

namespace AgentService.Interop.Implementation
{
	/// <summary>
	/// Class PlatformBinder. Defualt platform binder. 
	/// Connects to an instance of the AgentService 
	/// platform by using the platform access point 
	/// provided by the RemoteControlModule.
	/// </summary>
	/// <remarks>the class is thread safe</remarks>
	public class PlatformBinder : IPlatformBinder
	{
		/// <summary>
		/// synchronization flag.
		/// </summary>
		private object handle = new object();

		/// <summary>
		/// ArrayList containing the active connections.
		/// </summary>
		private ArrayList activeConnections;

		/// <summary>
		/// Cached array of active platform connections.
		/// </summary>
		private IPlatformChannel[] cached;

		/// <summary>
		/// Gets an array of the active connections managed
		/// by the platform binder.
		/// </summary>
		public IPlatformChannel[] ActiveConnections 
		{
			get 
			{
				if (cached != null)
					return cached;

				lock(this.handle)
				{
					this.cached = (IPlatformChannel[]) this.activeConnections.ToArray(typeof(IPlatformChannel));

					return this.cached;
				}
			}
		}
		
		/// <summary>
		/// Connects to an instance of the AgentService platform. Connection is 
		/// performed asynchronously and by useing the given user credentials.
		/// </summary>
		/// <param name="user">user name</param>
		/// <param name="pwd">user password</param>
		/// <param name="address">platform TCP address (IP address, port)</param>
		/// <param name="publicKey">platform public key</param>
		/// <returns>a connection channel with the platform.</returns>
		public IPlatformChannel Connect(string user, string pwd, TCPAddress address, byte[]  publicKey) 
		{
			PlatformChannel channel = new PlatformChannel(this, new User(user, pwd, UserGroup.Anonymous), address, publicKey);
			return channel;
		}

		/// <summary>
		/// Closes all the active connections managed by this
		/// binder.
		/// </summary>
		public void CloseAllChannels() 
		{
			lock(this.handle)
			{
				foreach(PlatformChannel channel in this.activeConnections)
				{
					channel.Close(false);
				}
				this.activeConnections.Clear();
				this.cached = null;
			}
		}

		/// <summary>
		/// Signals to this instancs of the PlatformBinder
		/// that the given channel has been closed.
		/// </summary>
		/// <param name="channel">signaling channel</param>
		internal void SignalClose(IPlatformChannel channel)
		{
			lock(this.handle)
			{
				if (this.activeConnections.Contains(channel) == false)
				{
					this.activeConnections.Remove(channel);
					this.cached = null;
				}
			}		
		}
		/// <summary>
		/// Signals to the PlatformBinder that the given
		/// channel has become active.
		/// </summary>
		/// <param name="channel">signaling channel</param>
		internal void SignalActive(IPlatformChannel channel)
		{
			lock(this.handle)
			{
				if (this.activeConnections.Contains(channel) == false)
				{
					this.activeConnections.Add(channel);
					this.cached = null;
				}
			}
		}
	}
}