//
// System.Runtime.Remoting.Channels.Tcp.TcpClientTransportSink.cs
//
// Author: Dietmar Maurer (dietmar@ximian.com)
//         Lluis Sanchez Gual (lluis@ideary.com)
//
// 2002 (C) Copyright, Ximian, Inc.
//

//
// Permission is hereby granted, free of charge, to any person obtaining
// a copy of this software and associated documentation files (the
// "Software"), to deal in the Software without restriction, including
// without limitation the rights to use, copy, modify, merge, publish,
// distribute, sublicense, and/or sell copies of the Software, and to
// permit persons to whom the Software is furnished to do so, subject to
// the following conditions:
// 
// The above copyright notice and this permission notice shall be
// included in all copies or substantial portions of the Software.
// 
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
// EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
// NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
// LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
// OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
// WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
//

using System;
using System.Runtime.Remoting.Channels;
using System.Runtime.Remoting.Messaging;
using System.Collections;
using System.IO;
using System.Threading;

namespace System.Runtime.Remoting.Channels.Tcp
{
	internal class TcpClientTransportSink : IClientChannelSink
	{
		string _host;
		int _port;
		
		public TcpClientTransportSink (string url)
		{
			string objectUri;
			string port;
			
			TcpChannel.ParseTcpURL (url, out _host, out port, out objectUri);
			
			try {
				if (port != null)
					_port = Convert.ToInt32 (port);
				else
					_port = 0;
			} catch {
				_host = null;
				_port = -1;
			}
		}

		public IDictionary Properties
		{
			get 
			{
				return null;
			}
		}

		public IClientChannelSink NextChannelSink
		{
			get 
			{
				// we are the last one
				return null;
			}
		}

		public void AsyncProcessRequest (IClientChannelSinkStack sinkStack, IMessage msg,
			ITransportHeaders headers, Stream requestStream)
		{
			TcpConnection connection = null;
			bool isOneWay = RemotingServices.IsOneWay (((IMethodMessage)msg).MethodBase);

			try
			{
				if (headers == null) headers = new TransportHeaders();
				headers [CommonTransportKeys.RequestUri] = ((IMethodMessage)msg).Uri;
				
				// Sends the stream using a connection from the pool
				// and creates a WorkItem that will wait for the
				// response of the server

				connection = TcpConnectionPool.GetConnection (_host, _port);
				TcpMessageIO.SendMessageStream (connection.Stream, requestStream, headers, connection.Buffer, isOneWay);
				connection.Stream.Flush ();

				if (!isOneWay) 
				{
					sinkStack.Push (this, connection);
					ThreadPool.QueueUserWorkItem (new WaitCallback(data => {
						try {
							ReadAsyncTcpMessage (data);
						} catch {}
						}), sinkStack);
				}
				else
					connection.Release();
			}
			catch
			{
				if (connection != null) connection.Release();
				if (!isOneWay) throw;
			}
		}

		private void ReadAsyncTcpMessage(object data)
		{
			// This method is called by a new thread to asynchronously
			// read the response to a request

			// The stack was provided as state data in QueueUserWorkItem
			IClientChannelSinkStack stack = (IClientChannelSinkStack)data;

			// The first sink in the stack is this sink. Pop it and
			// get the status data, which is the TcpConnection used to send
			// the request
			TcpConnection connection = (TcpConnection)stack.Pop(this);

			try
			{
				ITransportHeaders responseHeaders;

				// Read the response, blocking if necessary
				MessageStatus status = TcpMessageIO.ReceiveMessageStatus (connection.Stream, connection.Buffer);

				if (status != MessageStatus.MethodMessage)
					throw new RemotingException ("Unknown response message from server");

				Stream responseStream = TcpMessageIO.ReceiveMessageStream (connection.Stream, out responseHeaders, connection.Buffer);

				// Free the connection, so it can be reused
				connection.Release();
				connection = null;

				// Ok, proceed with the other sinks
				stack.AsyncProcessResponse (responseHeaders, responseStream);
			}
			catch
			{
				if (connection != null) connection.Release();
				throw;
			}
		}
	
		public void AsyncProcessResponse (IClientResponseChannelSinkStack sinkStack,
			object state, ITransportHeaders headers,
			Stream stream)
		{
			// Should never be called
			throw new NotSupportedException();
		}

		public Stream GetRequestStream (IMessage msg, ITransportHeaders headers)
		{
			return null;
		}
		
		public void ProcessMessage (IMessage msg,
			ITransportHeaders requestHeaders,
			Stream requestStream,
			out ITransportHeaders responseHeaders,
			out Stream responseStream)
		{
			TcpConnection connection = null;
			try
			{
				if (requestHeaders == null) requestHeaders = new TransportHeaders();
				requestHeaders [CommonTransportKeys.RequestUri] = ((IMethodMessage)msg).Uri;
				
				// Sends the message
				connection = TcpConnectionPool.GetConnection (_host, _port);
				TcpMessageIO.SendMessageStream (connection.Stream, requestStream, requestHeaders, connection.Buffer);
				connection.Stream.Flush ();

				// Reads the response
				MessageStatus status = TcpMessageIO.ReceiveMessageStatus (connection.Stream, connection.Buffer);

				if (status != MessageStatus.MethodMessage)
					throw new RemotingException ("Unknown response message from server");

				responseStream = TcpMessageIO.ReceiveMessageStream (connection.Stream, out responseHeaders, connection.Buffer);
			}
			finally
			{
				if (connection != null) 
					connection.Release();
			}
		}

	}


}