using System;
using System.Net;
using System.Net.Sockets;
using System.Text;
using System.Collections;
using System.IO;

namespace IvyBus
{
	/// <summary>
	/// Description résumée de IvyStream.
	/// </summary>
	public class IvyStream :  NetworkStream
	{
		BinaryReader input;
		BinaryWriter output;
		public IvyStream(Socket socket) : base( socket, true ) 
		{
			input = new BinaryReader( new BufferedStream(this),Encoding.ASCII);
			output = new BinaryWriter( new BufferedStream(this), Encoding.ASCII);
		}
		/* the protocol magic numbers */
		internal enum MessageType : ushort 
		{
			Bye = 0,			/* end of the peer */
			AddRegexp = 1,		/* the peer adds a regexp */
			Msg = 2,			/* the peer sends a message */
			Error = 3,			/* error message */
			DelRegexp = 4,		/* the peer removes one of his regex */
			EndRegexp = 5,		/* no more regexp in the handshake */
			StartRegexp = 6,	/* avoid race condition in concurrent connexions */
			DirectMsg = 7,		/* the peer sends a direct message */
			Die = 8,			/* the peer wants us to quit */
			Ping = 9,			/* checks the presence of the other */
			Pong = 10,			/* checks the presence of the other */
			AddBinding = 11,	/* other methods for binding message based on hash table */
			DelBinding = 12,	/* other methods for binding message based on hash table */
			ApplicationId = 13,	/* on start send my ID and priority */
		};
		/*
		 * message Syntax:
		 * this is a binary formated message use of network representation
		 * 
		 * message Format:
				MessageType, id , length, string 
		 */
		internal void  sendMsg(MessageType type, int id, byte[] arg)
		{
			try
			{
				output.Write( (ushort)IPAddress.HostToNetworkOrder( (short)type ) );
				output.Write( (ushort)IPAddress.HostToNetworkOrder( (short)id ) );
				output.Write( (ushort)IPAddress.HostToNetworkOrder( (short)arg.Length ) );
				output.Write( arg );
				output.Flush();
			}
			catch (IOException ie)
			{
				Console.Error.WriteLine("received an exception: " + ie.Message);
				Console.Error.WriteLine(ie.StackTrace);
			}
		}
		internal bool  receiveMsg(out MessageType type, out int id, out byte[] data)
		{
			int length = 0;
			data = null;
			id = 0;
			type = MessageType.Die;

			try
			{
				type = (MessageType)(ushort) IPAddress.NetworkToHostOrder( (short) input.ReadUInt16() );
				id = (ushort) IPAddress.NetworkToHostOrder( (short) input.ReadUInt16());
				length = (ushort) IPAddress.NetworkToHostOrder( (short) input.ReadUInt16());
				data = input.ReadBytes( length );
			}
			catch (EndOfStreamException nfe)
			{
				return false;
			}
			catch (FormatException nfe)
			{
				throw new IvyException("protocol error on msgType");
			}
			
			
			return true;
		}
		
	}
}