//
//  ========================================================================
//  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 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
        {
            if (getThreadPool()==null || !getThreadPool().dispatch(this))
            {
                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);
                }
            }
        }
    }
}