//
//  ========================================================================
//  Copyright (c) 1995-2014 Mort Bay Consulting Pty. Ltd.
//  ------------------------------------------------------------------------
//  All rights reserved. This program and the accompanying materials
//  are made available under the terms of the Eclipse Public License v1.0
//  and Apache License v2.0 which accompanies this distribution.
//
//      The Eclipse Public License is available at
//      http://www.eclipse.org/legal/epl-v10.html
//
//      The Apache License v2.0 is available at
//      http://www.opensource.org/licenses/apache2.0.php
//
//  You may elect to redistribute this code under either of these licenses.
//  ========================================================================
//

package org.eclipse.jetty.server.bio;

import java.io.IOException;
import java.net.InetAddress;
import java.net.ServerSocket;
import java.net.Socket;
import java.net.SocketException;
import java.util.HashSet;
import java.util.Set;
import java.util.concurrent.RejectedExecutionException;
import java.util.concurrent.ThreadPoolExecutor;

import org.eclipse.jetty.http.HttpException;
import org.eclipse.jetty.io.Buffer;
import org.eclipse.jetty.io.ConnectedEndPoint;
import org.eclipse.jetty.io.Connection;
import org.eclipse.jetty.io.EndPoint;
import org.eclipse.jetty.io.EofException;
import org.eclipse.jetty.io.bio.SocketEndPoint;
import org.eclipse.jetty.server.AbstractConnector;
import org.eclipse.jetty.server.AbstractHttpConnection;
import org.eclipse.jetty.server.BlockingHttpConnection;
import org.eclipse.jetty.server.Request;
import org.eclipse.jetty.util.component.AggregateLifeCycle;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;


/* ------------------------------------------------------------------------------- */
/**  Socket Connector.
 * This connector implements a traditional blocking IO and threading model.
 * Normal JRE sockets are used and a thread is allocated per connection.
 * Buffers are managed so that large buffers are only allocated to active connections.
 *
 * This Connector should only be used if NIO is not available.
 *
 * @org.apache.xbean.XBean element="bioConnector" description="Creates a BIO based socket connector"
 *
 *
 */
public class SocketConnector extends AbstractConnector
{
	private static final Logger LOG = LoggerFactory.getLogger(SocketConnector.class);

	protected ServerSocket _serverSocket;
	protected final Set<EndPoint> _connections;
	protected volatile int _localPort=-1;

	/* ------------------------------------------------------------ */
	/** Constructor.
	 *
	 */
	public SocketConnector()
	{
		_connections=new HashSet<EndPoint>();
	}

	/* ------------------------------------------------------------ */
	public Object getConnection()
	{
		return _serverSocket;
	}

	/* ------------------------------------------------------------ */
	public void open() throws IOException
	{
		// Create a new server socket and set to non blocking mode
		if (_serverSocket==null || _serverSocket.isClosed())
		_serverSocket= newServerSocket(getHost(),getPort(),getAcceptQueueSize());
		_serverSocket.setReuseAddress(getReuseAddress());
		_localPort=_serverSocket.getLocalPort();
		if (_localPort<=0)
			throw new IllegalStateException("port not allocated for "+this);

	}

	/* ------------------------------------------------------------ */
	protected ServerSocket newServerSocket(String host, int port,int backlog) throws IOException
	{
		ServerSocket ss= host==null?
			new ServerSocket(port,backlog):
			new ServerSocket(port,backlog,InetAddress.getByName(host));

		return ss;
	}

	/* ------------------------------------------------------------ */
	public void close() throws IOException
	{
		if (_serverSocket!=null)
			_serverSocket.close();
		_serverSocket=null;
		_localPort=-2;
	}

	/* ------------------------------------------------------------ */
	@Override
	public void accept(int acceptorID)
		throws IOException, InterruptedException
	{
		Socket socket = _serverSocket.accept();
		configure(socket);

		ConnectorEndPoint connection=new ConnectorEndPoint(socket);
		connection.dispatch();
	}

	/* ------------------------------------------------------------------------------- */
	/**
	 * Allows subclass to override Conection if required.
	 */
	protected Connection newConnection(EndPoint endpoint)
	{
		return new BlockingHttpConnection(this, endpoint, getServer());
	}

	/* ------------------------------------------------------------------------------- */
	@Override
	public void customize(EndPoint endpoint, Request request)
		throws IOException
	{
		ConnectorEndPoint connection = (ConnectorEndPoint)endpoint;
		int lrmit = isLowResources()?_lowResourceMaxIdleTime:_maxIdleTime;
		connection.setMaxIdleTime(lrmit);

		super.customize(endpoint, request);
	}

	/* ------------------------------------------------------------------------------- */
	public int getLocalPort()
	{
		return _localPort;
	}

	/* ------------------------------------------------------------------------------- */
	@Override
	protected void doStart() throws Exception
	{
		_connections.clear();
		super.doStart();
	}

	/* ------------------------------------------------------------------------------- */
	@Override
	protected void doStop() throws Exception
	{
		super.doStop();
		Set<EndPoint> set = new HashSet<EndPoint>();
		synchronized(_connections)
		{
			set.addAll(_connections);
		}
		for (EndPoint endPoint : set)
		{
			ConnectorEndPoint connection = (ConnectorEndPoint)endPoint;
			connection.close();
		}
	}

	@Override
	public void dump(Appendable out, String indent) throws IOException
	{
		super.dump(out, indent);
		Set<EndPoint> connections = new HashSet<EndPoint>();
		synchronized (_connections)
		{
			connections.addAll(_connections);
		}
		AggregateLifeCycle.dump(out, indent, connections);
	}

	/* ------------------------------------------------------------------------------- */
	/* ------------------------------------------------------------------------------- */
	/* ------------------------------------------------------------------------------- */
	protected class ConnectorEndPoint extends SocketEndPoint implements Runnable, ConnectedEndPoint
	{
		volatile Connection _connection;
		protected final Socket _socket;

		public ConnectorEndPoint(Socket socket) throws IOException
		{
			super(socket,_maxIdleTime);
			_connection = newConnection(this);
			_socket=socket;
		}

		public Connection getConnection()
		{
			return _connection;
		}

		public void setConnection(Connection connection)
		{
			if (_connection!=connection && _connection!=null)
				connectionUpgraded(_connection,connection);
			_connection=connection;
		}

		public void dispatch() throws IOException
		{
			ThreadPoolExecutor tpe = getThreadPool();
			if( tpe != null ) {
				try {
					tpe.execute(this);
					return;
				} catch(RejectedExecutionException e) {}
			}
			LOG.warn("dispatch failed for {}",_connection);
			close();
		}

		@Override
		public int fill(Buffer buffer) throws IOException
		{
			int l = super.fill(buffer);
			if (l<0)
			{
				if (!isInputShutdown())
					shutdownInput();
				if (isOutputShutdown())
					close();
			}
			return l;
		}

		@Override
		public void close() throws IOException
		{
			if (_connection instanceof AbstractHttpConnection)
				((AbstractHttpConnection)_connection).getRequest().getAsyncContinuation().cancel();
			super.close();
		}

		public void run()
		{
			try
			{
				connectionOpened(_connection);
				synchronized(_connections)
				{
					_connections.add(this);
				}

				while (isStarted() && !isClosed())
				{
					if (_connection.isIdle())
					{
						if (isLowResources())
							setMaxIdleTime(getLowResourcesMaxIdleTime());
					}

					_connection=_connection.handle();
				}
			}
			catch (EofException e)
			{
				LOG.debug("EOF", e);
				try{close();}
				catch(IOException e2){LOG.trace("",e2);}
			}
			catch (SocketException e)
			{
				LOG.debug("EOF", e);
				try{close();}
				catch(IOException e2){LOG.trace("",e2);}
			}
			catch (HttpException e)
			{
				LOG.debug("BAD", e);
				try{close();}
				catch(IOException e2){LOG.trace("",e2);}
			}
			catch(Exception e)
			{
				LOG.warn("handle failed?",e);
				try{close();}
				catch(IOException e2){LOG.trace("",e2);}
			}
			finally
			{
				connectionClosed(_connection);
				synchronized(_connections)
				{
					_connections.remove(this);
				}

				// wait for client to close, but if not, close ourselves.
				try
				{
					if (!_socket.isClosed())
					{
						long timestamp=System.currentTimeMillis();
						int max_idle=getMaxIdleTime();

						_socket.setSoTimeout(getMaxIdleTime());
						int c=0;
						do
						{
							c = _socket.getInputStream().read();
						}
						while (c>=0 && (System.currentTimeMillis()-timestamp)<max_idle);
						if (!_socket.isClosed())
							_socket.close();
					}
				}
				catch(IOException e)
				{
					LOG.trace("",e);
				}
			}
		}
	}
}