/**
 * $RCSfile: JingleSession.java,v $
 * $Revision: 1.20 $
 * $Date: 2007/07/18 18:29:21 $
 *
 * Copyright (C) 2002-2006 Jive Software. All rights reserved.
 * ====================================================================
 * The Jive Software License (based on Apache Software License, Version 1.1)
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 *
 * 3. The end-user documentation included with the redistribution,
 *    if any, must include the following acknowledgment:
 *       "This product includes software developed by
 *        Jive Software (http://www.jivesoftware.com)."
 *    Alternately, this acknowledgment may appear in the software itself,
 *    if and wherever such third-party acknowledgments normally appear.
 *
 * 4. The names "Smack" and "Jive Software" must not be used to
 *    endorse or promote products derived from this software without
 *    prior written permission. For written permission, please
 *    contact webmaster@jivesoftware.com.
 *
 * 5. Products derived from this software may not be called "Smack",
 *    nor may "Smack" appear in their name, without prior written
 *    permission of Jive Software.
 *
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED.  IN NO EVENT SHALL JIVE SOFTWARE OR
 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 * ====================================================================
 */

package org.jivesoftware.smackx.jingle;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.Random;

import org.jivesoftware.smack.ConnectionListener;
import org.jivesoftware.smack.PacketListener;
import org.jivesoftware.smack.XMPPConnection;
import org.jivesoftware.smack.XMPPException;
import org.jivesoftware.smack.filter.PacketFilter;
import org.jivesoftware.smack.packet.IQ;
import org.jivesoftware.smack.packet.Packet;
import org.jivesoftware.smack.packet.PacketExtension;
import org.jivesoftware.smack.packet.XMPPError;
import org.jivesoftware.smackx.jingle.listeners.JingleListener;
import org.jivesoftware.smackx.jingle.listeners.JingleMediaListener;
import org.jivesoftware.smackx.jingle.listeners.JingleSessionListener;
import org.jivesoftware.smackx.jingle.listeners.JingleTransportListener;
import org.jivesoftware.smackx.jingle.media.JingleMediaManager;
import org.jivesoftware.smackx.jingle.media.JingleMediaSession;
import org.jivesoftware.smackx.jingle.media.MediaNegotiator;
import org.jivesoftware.smackx.jingle.media.MediaReceivedListener;
import org.jivesoftware.smackx.jingle.media.PayloadType;
import org.jivesoftware.smackx.jingle.nat.JingleTransportManager;
import org.jivesoftware.smackx.jingle.nat.TransportCandidate;
import org.jivesoftware.smackx.jingle.nat.TransportNegotiator;
import org.jivesoftware.smackx.jingle.nat.TransportResolver;
import org.jivesoftware.smackx.packet.Jingle;
import org.jivesoftware.smackx.packet.JingleError;

/**
 * An abstract Jingle session. <p/> This class contains some basic properties of
 * every Jingle session. However, the concrete implementation can be found in
 * subclasses.
 * 
 * @author Alvaro Saurin
 * @author Jeff Williams
 */
public class JingleSession extends JingleNegotiator implements MediaReceivedListener {

	private static final SmackLogger LOGGER = SmackLogger.getLogger(JingleSession.class);

	// static
    private static final HashMap sessions = new HashMap();

    private static final Random randomGenerator = new Random();

    // non-static

    private String initiator; // Who started the communication

    private String responder; // The other endpoint

    private String sid; // A unique id that identifies this session

    ConnectionListener connectionListener;
    
    PacketListener packetListener;

    PacketFilter packetFilter;

    protected List<JingleMediaManager> jingleMediaManagers = null;

    private boolean closed = false;

    private JingleSessionState sessionState;

    private List<ContentNegotiator> contentNegotiators;

    private JingleSessionRequest sessionRequest;

    private XMPPConnection connection;

    private String sessionInitPacketID;
    
    private Map<String, JingleMediaSession> mediaSessionMap;

    /**
     * Full featured JingleSession constructor
     * 
     * @param conn
     *            XMPPConnection
     * @param initiator
     *            the initiator JID
     * @param responder
     *            the responder JID
     * @param sessionid
     *            the session ID
     * @param jingleMediaManager
     *            the jingleMediaManager
     */
    public JingleSession(XMPPConnection conn, String initiator, String responder, String sessionid,
            List<JingleMediaManager> jingleMediaManagers) {
        super();

        this.initiator = initiator;
        this.responder = responder;
        this.sid = sessionid;
        this.jingleMediaManagers = jingleMediaManagers;
        this.setSession(this);
        this.connection = conn;

        // Initially, we don't known the session state.
        setSessionState(JingleSessionStateUnknown.getInstance());
        
        contentNegotiators = new ArrayList<ContentNegotiator>();
        mediaSessionMap = new HashMap<String, JingleMediaSession>();

        // Add the session to the list and register the listeneres
        registerInstance();
        installConnectionListeners(conn);
    }

    /**
     * JingleSession constructor (for an outgoing Jingle session)
     * 
     * @param conn
     *            XMPPConnection
     * @param initiator
     *            the initiator JID
     * @param responder
     *            the responder JID
     * @param jingleMediaManager
     *            the jingleMediaManager
     */
    public JingleSession(XMPPConnection conn, JingleSessionRequest request, String initiator, String responder,
            List<JingleMediaManager> jingleMediaManagers) {
        this(conn, initiator, responder, generateSessionId(), jingleMediaManagers);
        sessionRequest = request;
    }

    /**
     * Get the session initiator
     * 
     * @return the initiator
     */
    public String getInitiator() {
        return initiator;
    }

    public XMPPConnection getConnection() {
        return connection;
    }

    /**
     * Set the session initiator
     * 
     * @param initiator
     *            the initiator to set
     */
    public void setInitiator(String initiator) {
        this.initiator = initiator;
    }

    /**
     * Get the Media Manager of this Jingle Session
     * 
     * @return
     */
    public List<JingleMediaManager> getMediaManagers() {
        return jingleMediaManagers;
    }

    /**
     * Set the Media Manager of this Jingle Session
     * 
     * @param jingleMediaManager
     */
    public void setMediaManagers(List<JingleMediaManager> jingleMediaManagers) {
        this.jingleMediaManagers = jingleMediaManagers;
    }

    /**
     * Get the session responder
     * 
     * @return the responder
     */
    public String getResponder() {
        return responder;
    }

    /**
     * Set the session responder.
     * 
     * @param responder
     *            the receptor to set
     */
    public void setResponder(String responder) {
        this.responder = responder;
    }

    /**
     * Get the session ID
     * 
     * @return the sid
     */
    public String getSid() {
        return sid;
    }

    /**
     * Set the session ID
     * 
     * @param sessionId
     *            the sid to set
     */
    protected void setSid(String sessionId) {
        sid = sessionId;
    }

    /**
     * Generate a unique session ID.
     */
    protected static String generateSessionId() {
        return String.valueOf(Math.abs(randomGenerator.nextLong()));
    }

    /**
     * Validate the state changes.
     */

    public void setSessionState(JingleSessionState stateIs) {

        LOGGER.debug("Session state change: " + sessionState + "->" + stateIs);
        stateIs.enter();
        sessionState = stateIs;
    }

    public JingleSessionState getSessionState() {
        return sessionState;
    }

    /**
     * Return true if all of the media managers have finished
     */
    public boolean isFullyEstablished() {
        boolean result = true;
        for (ContentNegotiator contentNegotiator : contentNegotiators) {
            if (!contentNegotiator.isFullyEstablished())
                result = false;
        }
        return result;
    }

    // ----------------------------------------------------------------------------------------------------------
    // Receive section
    // ----------------------------------------------------------------------------------------------------------

    /**
     * Process and respond to an incoming packet. <p/> This method is called
     * from the packet listener dispatcher when a new packet has arrived. The
     * method is responsible for recognizing the packet type and, depending on
     * the current state, delivering it to the right event handler and wait for
     * a response. The response will be another Jingle packet that will be sent
     * to the other end point.
     * 
     * @param iq
     *            the packet received
     * @return the new Jingle packet to send.
     * @throws XMPPException
     */
    public synchronized void receivePacketAndRespond(IQ iq) throws XMPPException {
        List<IQ> responses = new ArrayList<IQ>();

        String responseId = null;

        LOGGER.debug("Packet: " + iq.toXML());

        try {

            // Dispatch the packet to the JingleNegotiators and get back a list of the results.
            responses.addAll(dispatchIncomingPacket(iq, null));

            if (iq != null) {
                responseId = iq.getPacketID();

                // Send the IQ to each of the content negotiators for further processing.
                // Each content negotiator may pass back a list of JingleContent for addition to the response packet.

                for (ContentNegotiator contentNegotiator : contentNegotiators) {
                    responses.addAll(contentNegotiator.dispatchIncomingPacket(iq, responseId));
                }

            }
            // Acknowledge the IQ reception
            // Not anymore.  The state machine generates an appropriate response IQ that
            // gets sent back at the end of this routine.
            //sendAck(iq);

        } catch (JingleException e) {
            // Send an error message, if present
            JingleError error = e.getError();
            if (error != null) {
                responses.add(createJingleError(iq, error));
            }

            // Notify the session end and close everything...
            triggerSessionClosedOnError(e);
        }

        //        // If the response is anything other than a RESULT then send it now.
        //        if ((response != null) && (!response.getType().equals(IQ.Type.RESULT))) {
        //            getConnection().sendPacket(response);
        //        }

        // Loop through all of the responses and send them.
        for (IQ response : responses) {
            sendPacket(response);
        }
    }

    /**
     * Dispatch an incoming packet. The method is responsible for recognizing
     * the packet type and, depending on the current state, delivering the
     * packet to the right event handler and wait for a response.
     * 
     * @param iq
     *            the packet received
     * @return the new Jingle packet to send.
     * @throws XMPPException
     */
    public List<IQ> dispatchIncomingPacket(IQ iq, String id) throws XMPPException {
        List<IQ> responses = new ArrayList<IQ>();
        IQ response = null;

        if (iq != null) {
            if (iq.getType().equals(IQ.Type.ERROR)) {
                // Process errors
                // TODO getState().eventError(iq);
            } else if (iq.getType().equals(IQ.Type.RESULT)) {
                // Process ACKs
                if (isExpectedId(iq.getPacketID())) {

                    // The other side provisionally accepted our session-initiate.
                    // Kick off some negotiators.
                    if (iq.getPacketID().equals(sessionInitPacketID)) {
                        startNegotiators();
                    }
                    removeExpectedId(iq.getPacketID());
                }
            } else if (iq instanceof Jingle) {
                // It is not an error: it is a Jingle packet...
                Jingle jin = (Jingle) iq;
                JingleActionEnum action = jin.getAction();

                // Depending on the state we're in we'll get different processing actions.
                // (See Design Patterns AKA GoF State behavioral pattern.)
                getSessionState().processJingle(this, jin, action);
            }
        }

        if (response != null) {
            // Save the packet id, for recognizing ACKs...
            addExpectedId(response.getPacketID());
            responses.add(response);
        }

        return responses;
    }

    /**
     * Add a new content negotiator on behalf of a <content> section received.
     */
    public void addContentNegotiator(ContentNegotiator inContentNegotiator) {
        contentNegotiators.add(inContentNegotiator);
    }

  

     // ----------------------------------------------------------------------------------------------------------
    // Send section
    // ----------------------------------------------------------------------------------------------------------

    public void sendPacket(IQ iq) {

        if (iq instanceof Jingle) {
            //            Jingle jingle = (Jingle) iq;
            //
            //            JingleActionEnum action = jingle.getAction();
            //
            //            switch (getSessionState()) {
            //                case UNKNOWN:
            //                    sendUnknownStateAction(jingle, action);
            //                    break;
            //
            //                case PENDING:
            //                    sendPendingStateAction(jingle, action);
            //                    break;
            //
            //                case ACTIVE:
            //                    sendActiveStateAction(jingle, action);
            //                    break;
            //
            //                case ENDED:
            //                    sendEndedStateAction(jingle, action);
            //                    break;
            //
            //                default:
            //                    break;
            //            }

            sendFormattedJingle((Jingle) iq);

        } else {

            getConnection().sendPacket(iq);
        }
    }

    /**
     * Complete and send a packet. Complete all the null fields in a Jingle
     * reponse, using the session information we have.
     * 
     * @param jout
     *            the Jingle packet we want to complete and send
     */
    public Jingle sendFormattedJingle(Jingle jout) {
        return sendFormattedJingle(null, jout);
    }

    /**
     * Complete and send a packet. Complete all the null fields in a Jingle
     * reponse, using the session information we have or some info from the
     * incoming packet.
     * 
     * @param iq
     *            The Jingle packet we are responing to
     * @param jout
     *            the Jingle packet we want to complete and send
     */
    public Jingle sendFormattedJingle(IQ iq, Jingle jout) {
        if (jout != null) {
            if (jout.getInitiator() == null) {
                jout.setInitiator(getInitiator());
            }

            if (jout.getResponder() == null) {
                jout.setResponder(getResponder());
            }

            if (jout.getSid() == null) {
                jout.setSid(getSid());
            }

            String me = getConnection().getUser();
            String other = getResponder().equals(me) ? getInitiator() : getResponder();

            if (jout.getTo() == null) {
                if (iq != null) {
                    jout.setTo(iq.getFrom());
                } else {
                    jout.setTo(other);
                }
            }

            if (jout.getFrom() == null) {
                if (iq != null) {
                    jout.setFrom(iq.getTo());
                } else {
                    jout.setFrom(me);
                }
            }

            // The the packet.
            if ((getConnection() != null) && (getConnection().isConnected()))
            	getConnection().sendPacket(jout);
        }
        return jout;
    }

    /**
     *  @param inJingle
     *  @param inAction
     */
    //    private void sendUnknownStateAction(Jingle inJingle, JingleActionEnum inAction) {
    //
    //        if (inAction == JingleActionEnum.SESSION_INITIATE) {
    //            // Prepare to receive and act on response packets.
    //            updatePacketListener();
    //
    //            // Send the actual packet.
    //            sendPacket(inJingle);
    //
    //            // Change to the PENDING state.
    //            setSessionState(JingleSessionStateEnum.PENDING);
    //        } else {
    //            throw new IllegalStateException("Only session-initiate allowed in the UNKNOWN state.");
    //        }
    //    }
    /**
     *  @param inJingle
     *  @param inAction
     */
    private void sendPendingStateAction(Jingle inJingle, JingleActionEnum inAction) {

    }

    /**
     *  @param inJingle
     *  @param inAction
     */
    private void sendActiveStateAction(Jingle inJingle, JingleActionEnum inAction) {

    }

    /**
     *  @param inJingle
     *  @param inAction
     */
    private void sendEndedStateAction(Jingle inJingle, JingleActionEnum inAction) {

    }

    /**
     * Acknowledge a IQ packet.
     * 
     * @param iq
     *            The IQ to acknowledge
     */
    public IQ createAck(IQ iq) {
        IQ result = null;

        if (iq != null) {
            // Don't acknowledge ACKs, errors...
            if (iq.getType().equals(IQ.Type.SET)) {
                IQ ack = createIQ(iq.getPacketID(), iq.getFrom(), iq.getTo(), IQ.Type.RESULT);

                // No! Don't send it.  Let it flow to the normal way IQ results get processed and sent.
                // getConnection().sendPacket(ack);
                result = ack;
            }
        }
        return result;
    }

    /**
     * Send a content info message.
     */
    //    public synchronized void sendContentInfo(ContentInfo ci) {
    //        sendPacket(new Jingle(new JingleContentInfo(ci)));
    //    }
    /*
     * (non-Javadoc)
     * 
     * @see java.lang.Object#hashCode()
     */
    public int hashCode() {
        return Jingle.getSessionHash(getSid(), getInitiator());
    }

    /*
     * (non-Javadoc)
     * 
     * @see java.lang.Object#equals(java.lang.Object)
     */
    public boolean equals(Object obj) {
        if (this == obj) {
            return true;
        }
        if (obj == null) {
            return false;
        }
        if (getClass() != obj.getClass()) {
            return false;
        }

        final JingleSession other = (JingleSession) obj;

        if (initiator == null) {
            if (other.initiator != null) {
                return false;
            }
        } else if (!initiator.equals(other.initiator)) {
            // Todo check behavior
            // return false;
        }

        if (responder == null) {
            if (other.responder != null) {
                return false;
            }
        } else if (!responder.equals(other.responder)) {
            return false;
        }

        if (sid == null) {
            if (other.sid != null) {
                return false;
            }
        } else if (!sid.equals(other.sid)) {
            return false;
        }

        return true;
    }

    // Instances management

    /**
     * Clean a session from the list.
     * 
     * @param connection
     *            The connection to clean up
     */
    private void unregisterInstanceFor(XMPPConnection connection) {
        synchronized (sessions) {
            sessions.remove(connection);
        }
    }

    /**
     * Register this instance.
     */
    private void registerInstance() {
        synchronized (sessions) {
            sessions.put(getConnection(), this);
        }
    }

    /**
     * Returns the JingleSession related to a particular connection.
     * 
     * @param con
     *            A XMPP connection
     * @return a Jingle session
     */
    public static JingleSession getInstanceFor(XMPPConnection con) {
        if (con == null) {
            throw new IllegalArgumentException("Connection cannot be null");
        }

        JingleSession result = null;
        synchronized (sessions) {
            if (sessions.containsKey(con)) {
                result = (JingleSession) sessions.get(con);
            }
        }

        return result;
    }

    /**
     * Configure a session, setting some action listeners...
     * 
     * @param connection
     *            The connection to set up
     */
    private void installConnectionListeners(final XMPPConnection connection) {
        if (connection != null) {
            connectionListener = new ConnectionListener() {
                public void connectionClosed() {
                    unregisterInstanceFor(connection);
                }

                public void connectionClosedOnError(java.lang.Exception e) {
                    unregisterInstanceFor(connection);
                }

                public void reconnectingIn(int i) {
                }

                public void reconnectionSuccessful() {
                }

                public void reconnectionFailed(Exception exception) {
                }
            };
            connection.addConnectionListener(connectionListener);
        }
    }
    
    private void removeConnectionListener() {
    	if (connectionListener != null) {
    		getConnection().removeConnectionListener(connectionListener);
    		
    		LOGGER.debug("JINGLE SESSION: REMOVE CONNECTION LISTENER");
    	}
    }

    /**
     * Remove the packet listener used for processing packet.
     */
    protected void removePacketListener() {
        if (packetListener != null) {
            getConnection().removePacketListener(packetListener);

            LOGGER.debug("JINGLE SESSION: REMOVE PACKET LISTENER");
        }
    }

    /**
     * Install the packet listener. The listener is responsible for responding
     * to any packet that we receive...
     */
    protected void updatePacketListener() {
        removePacketListener();

        LOGGER.debug("UpdatePacketListener");

        packetListener = new PacketListener() {
            public void processPacket(Packet packet) {
                try {
                    receivePacketAndRespond((IQ) packet);
                } catch (XMPPException e) {
                    e.printStackTrace();
                }
            }
        };

        packetFilter = new PacketFilter() {
            public boolean accept(Packet packet) {

                if (packet instanceof IQ) {
                    IQ iq = (IQ) packet;

                    String me = getConnection().getUser();

                    if (!iq.getTo().equals(me)) {
                        return false;
                    }

                    String other = getResponder().equals(me) ? getInitiator() : getResponder();

                    if (iq.getFrom() == null || !iq.getFrom().equals(other == null ? "" : other)) {
                        return false;
                    }

                    if (iq instanceof Jingle) {
                        Jingle jin = (Jingle) iq;

                        String sid = jin.getSid();
                        if (sid == null || !sid.equals(getSid())) {
                            LOGGER.debug("Ignored Jingle(SID) " + sid + "|" + getSid() + " :" + iq.toXML());
                            return false;
                        }
                        String ini = jin.getInitiator();
                        if (!ini.equals(getInitiator())) {
                            LOGGER.debug("Ignored Jingle(INI): " + iq.toXML());
                            return false;
                        }
                    } else {
                        // We accept some non-Jingle IQ packets: ERRORs and ACKs
                        if (iq.getType().equals(IQ.Type.SET)) {
                            LOGGER.debug("Ignored Jingle(TYPE): " + iq.toXML());
                            return false;
                        } else if (iq.getType().equals(IQ.Type.GET)) {
                            LOGGER.debug("Ignored Jingle(TYPE): " + iq.toXML());
                            return false;
                        }
                    }
                    return true;
                }
                return false;
            }
        };

        getConnection().addPacketListener(packetListener, packetFilter);
    }

    // Listeners

    /**
     * Add a listener for jmf negotiation events
     * 
     * @param li
     *            The listener
     */
    public void addMediaListener(JingleMediaListener li) {
        for (ContentNegotiator contentNegotiator : contentNegotiators) {
            if (contentNegotiator.getMediaNegotiator() != null) {
                contentNegotiator.getMediaNegotiator().addListener(li);
            }
        }

    }

    /**
     * Remove a listener for jmf negotiation events
     * 
     * @param li
     *            The listener
     */
    public void removeMediaListener(JingleMediaListener li) {
        for (ContentNegotiator contentNegotiator : contentNegotiators) {
            if (contentNegotiator.getMediaNegotiator() != null) {
                contentNegotiator.getMediaNegotiator().removeListener(li);
            }
        }
    }

    /**
     * Add a listener for transport negotiation events
     * 
     * @param li
     *            The listener
     */
    public void addTransportListener(JingleTransportListener li) {
        for (ContentNegotiator contentNegotiator : contentNegotiators) {
            if (contentNegotiator.getTransportNegotiator() != null) {
                contentNegotiator.getTransportNegotiator().addListener(li);
            }
        }
    }

    /**
     * Remove a listener for transport negotiation events
     * 
     * @param li
     *            The listener
     */
    public void removeTransportListener(JingleTransportListener li) {
        for (ContentNegotiator contentNegotiator : contentNegotiators) {
            if (contentNegotiator.getTransportNegotiator() != null) {
                contentNegotiator.getTransportNegotiator().removeListener(li);
            }
        }
    }

    /**
     * Setup the listeners that act on events coming from the lower level negotiators.
     */

    public void setupListeners() {

        JingleMediaListener jingleMediaListener = new JingleMediaListener() {
            public void mediaClosed(PayloadType cand) {
            }

            public void mediaEstablished(PayloadType pt) {
                if (isFullyEstablished()) {
                    Jingle jout = new Jingle(JingleActionEnum.SESSION_ACCEPT);

                    // Build up a response packet from each media manager.
                    for (ContentNegotiator contentNegotiator : contentNegotiators) {
                        if (contentNegotiator.getNegotiatorState() == JingleNegotiatorState.SUCCEEDED)
                            jout.addContent(contentNegotiator.getJingleContent());
                    }
                    // Send the "accept" and wait for the ACK
                    addExpectedId(jout.getPacketID());
                    sendPacket(jout);

                    //triggerSessionEstablished();

                }
            }
        };

        JingleTransportListener jingleTransportListener = new JingleTransportListener() {

            public void transportEstablished(TransportCandidate local, TransportCandidate remote) {
                if (isFullyEstablished()) {
 
                	// Indicate that this session is active.
                	setSessionState(JingleSessionStateActive.getInstance());
                	
                	for (ContentNegotiator contentNegotiator : contentNegotiators) {
                        if (contentNegotiator.getNegotiatorState() == JingleNegotiatorState.SUCCEEDED)
                            contentNegotiator.triggerContentEstablished();
                    }

                    if (getSessionState().equals(JingleSessionStatePending.getInstance())) {
                    	
                        Jingle jout = new Jingle(JingleActionEnum.SESSION_ACCEPT);

                        // Build up a response packet from each media manager.
                        for (ContentNegotiator contentNegotiator : contentNegotiators) {
                            if (contentNegotiator.getNegotiatorState() == JingleNegotiatorState.SUCCEEDED)
                                jout.addContent(contentNegotiator.getJingleContent());
                        }
                        // Send the "accept" and wait for the ACK
                        addExpectedId(jout.getPacketID());
                        sendPacket(jout);
                    }
                }
            }

            public void transportClosed(TransportCandidate cand) {
            }

            public void transportClosedOnError(XMPPException e) {
            }
        };

        addMediaListener(jingleMediaListener);
        addTransportListener(jingleTransportListener);
    }

    // Triggers

    /**
     * Trigger a session closed event.
     */
    protected void triggerSessionClosed(String reason) {
        //        for (ContentNegotiator contentNegotiator : contentNegotiators) {
        //
        //            contentNegotiator.stopJingleMediaSession();
        //
        //            for (TransportCandidate candidate : contentNegotiator.getTransportNegotiator().getOfferedCandidates())
        //                candidate.removeCandidateEcho();
        //        }

        List<JingleListener> listeners = getListenersList();
        for (JingleListener li : listeners) {
            if (li instanceof JingleSessionListener) {
                JingleSessionListener sli = (JingleSessionListener) li;
                sli.sessionClosed(reason, this);
            }
        }
        close();
    }

    /**
     * Trigger a session closed event due to an error.
     */
    protected void triggerSessionClosedOnError(XMPPException exc) {
        for (ContentNegotiator contentNegotiator : contentNegotiators) {

            contentNegotiator.stopJingleMediaSession();

            for (TransportCandidate candidate : contentNegotiator.getTransportNegotiator().getOfferedCandidates())
                candidate.removeCandidateEcho();
        }
        List<JingleListener> listeners = getListenersList();
        for (JingleListener li : listeners) {
            if (li instanceof JingleSessionListener) {
                JingleSessionListener sli = (JingleSessionListener) li;
                sli.sessionClosedOnError(exc, this);
            }
        }
        close();
    }

    /**
     * Trigger a session established event.
     */
    //    protected void triggerSessionEstablished() {
    //        List<JingleListener> listeners = getListenersList();
    //        for (JingleListener li : listeners) {
    //            if (li instanceof JingleSessionListener) {
    //                JingleSessionListener sli = (JingleSessionListener) li;
    //                sli.sessionEstablished(this);
    //            }
    //        }
    //    }
    /**
     * Trigger a media received event.
     */
    protected void triggerMediaReceived(String participant) {
        List<JingleListener> listeners = getListenersList();
        for (JingleListener li : listeners) {
            if (li instanceof JingleSessionListener) {
                JingleSessionListener sli = (JingleSessionListener) li;
                sli.sessionMediaReceived(this, participant);
            }
        }
    }

    /**
     * Trigger a session redirect event.
     */
    //    protected void triggerSessionRedirect(String arg) {
    //        List<JingleListener> listeners = getListenersList();
    //        for (JingleListener li : listeners) {
    //            if (li instanceof JingleSessionListener) {
    //                JingleSessionListener sli = (JingleSessionListener) li;
    //                sli.sessionRedirected(arg, this);
    //            }
    //        }
    //    }
    /**
     * Trigger a session decline event.
     */
    //    protected void triggerSessionDeclined(String reason) {
    //        List<JingleListener> listeners = getListenersList();
    //        for (JingleListener li : listeners) {
    //            if (li instanceof JingleSessionListener) {
    //                JingleSessionListener sli = (JingleSessionListener) li;
    //                sli.sessionDeclined(reason, this);
    //            }
    //        }
    //        for (ContentNegotiator contentNegotiator : contentNegotiators) {
    //            for (TransportCandidate candidate : contentNegotiator.getTransportNegotiator().getOfferedCandidates())
    //                candidate.removeCandidateEcho();
    //        }
    //    }
    /**
     * Terminates the session with default reason.
     * 
     * @throws XMPPException
     */
    public void terminate() throws XMPPException {
        terminate("Closed Locally");
    }

    /**
     * Terminates the session with a custom reason.
     * 
     * @throws XMPPException
     */
    public void terminate(String reason) throws XMPPException {
        if (isClosed())
            return;
        LOGGER.debug("Terminate " + reason);
        Jingle jout = new Jingle(JingleActionEnum.SESSION_TERMINATE);
        jout.setType(IQ.Type.SET);
        sendPacket(jout);
        triggerSessionClosed(reason);
    }

    /**
     * Terminate negotiations.
     */
    public void close() {
        if (isClosed())
            return;

        // Set the session state to ENDED.
        setSessionState(JingleSessionStateEnded.getInstance());

        for (ContentNegotiator contentNegotiator : contentNegotiators) {

            contentNegotiator.stopJingleMediaSession();

            for (TransportCandidate candidate : contentNegotiator.getTransportNegotiator().getOfferedCandidates())
                candidate.removeCandidateEcho();

            contentNegotiator.close();
        }
        removePacketListener();
        removeConnectionListener();
        getConnection().removeConnectionListener(connectionListener);
        LOGGER.debug("Negotiation Closed: " + getConnection().getUser() + " " + sid);
        super.close();

    }

    public boolean isClosed() {
        return getSessionState().equals(JingleSessionStateEnded.getInstance());
    }

    // Packet and error creation

    /**
     * A convience method to create an IQ packet.
     * 
     * @param ID
     *            The packet ID of the
     * @param to
     *            To whom the packet is addressed.
     * @param from
     *            From whom the packet is sent.
     * @param type
     *            The iq type of the packet.
     * @return The created IQ packet.
     */
    public static IQ createIQ(String ID, String to, String from, IQ.Type type) {
        IQ iqPacket = new IQ() {
            public String getChildElementXML() {
                return null;
            }
        };

        iqPacket.setPacketID(ID);
        iqPacket.setTo(to);
        iqPacket.setFrom(from);
        iqPacket.setType(type);

        return iqPacket;
    }

    /**
     * A convience method to create an error packet.
     * 
     * @param ID
     *            The packet ID of the
     * @param to
     *            To whom the packet is addressed.
     * @param from
     *            From whom the packet is sent.
     * @param errCode
     *            The error code.
     * @param errStr
     *            The error string.
     * @return The created IQ packet.
     */
    public static IQ createError(String ID, String to, String from, int errCode, XMPPError error) {

        IQ iqError = createIQ(ID, to, from, IQ.Type.ERROR);
        iqError.setError(error);

        LOGGER.debug("Created Error Packet:" + iqError.toXML());

        return iqError;
    }

    /**
     * Complete and send an error. Complete all the null fields in an IQ error
     * reponse, using the sesssion information we have or some info from the
     * incoming packet.
     * 
     * @param iq
     *            The Jingle packet we are responing to
     * @param error
     *            the IQ packet we want to complete and send
     */
    public IQ createJingleError(IQ iq, JingleError jingleError) {
        IQ errorPacket = null;
        if (jingleError != null) {
            errorPacket = createIQ(getSid(), iq.getFrom(), iq.getTo(), IQ.Type.ERROR);

            List<PacketExtension> extList = new ArrayList<PacketExtension>();
            extList.add(jingleError);
            XMPPError error = new XMPPError(0, XMPPError.Type.CANCEL, jingleError.toString(), "", extList);

            // Fill in the fields with the info from the Jingle packet
            errorPacket.setPacketID(iq.getPacketID());
            errorPacket.setError(error);
            //            errorPacket.addExtension(jingleError);

            // NO! Let the normal state machinery do all of the sending.
            // getConnection().sendPacket(perror);
            LOGGER.error("Error sent: " + errorPacket.toXML());
        }
        return errorPacket;
    }

    /**
     * Called when new Media is received.
     */
    public void mediaReceived(String participant) {
        triggerMediaReceived(participant);
    }

    /**
     * This is the starting point for intitiating a new session.
     * 
     * @throws IllegalStateException
     */
    public void startOutgoing() throws IllegalStateException {

        updatePacketListener();
        setSessionState(JingleSessionStatePending.getInstance());

        Jingle jingle = new Jingle(JingleActionEnum.SESSION_INITIATE);

        // Create a content negotiator for each media manager on the session.
        for (JingleMediaManager mediaManager : getMediaManagers()) {
            ContentNegotiator contentNeg = new ContentNegotiator(this, ContentNegotiator.INITIATOR, mediaManager.getName());

            // Create the media negotiator for this content description.
            contentNeg.setMediaNegotiator(new MediaNegotiator(this, mediaManager, mediaManager.getPayloads(), contentNeg));

            JingleTransportManager transportManager = mediaManager.getTransportManager();
            TransportResolver resolver = null;
            try {
                resolver = transportManager.getResolver(this);
            } catch (XMPPException e) {
                e.printStackTrace();
            }

            if (resolver.getType().equals(TransportResolver.Type.rawupd)) {
                contentNeg.setTransportNegotiator(new TransportNegotiator.RawUdp(this, resolver, contentNeg));
            }
            if (resolver.getType().equals(TransportResolver.Type.ice)) {
                contentNeg.setTransportNegotiator(new TransportNegotiator.Ice(this, resolver, contentNeg));
            }

            addContentNegotiator(contentNeg);
        }

        // Give each of the content negotiators a chance to return a portion of the structure to make the Jingle packet.
        for (ContentNegotiator contentNegotiator : contentNegotiators) {
            jingle.addContent(contentNegotiator.getJingleContent());
        }

        // Save the session-initiate packet ID, so that we can respond to it.
        sessionInitPacketID = jingle.getPacketID();

        sendPacket(jingle);

        // Now setup to track the media negotiators, so that we know when (if) to send a session-accept.
        setupListeners();

        // Give each of the content negotiators a chance to start 
        // and return a portion of the structure to make the Jingle packet.
        for (ContentNegotiator contentNegotiator : contentNegotiators) {
            contentNegotiator.start();
        }
    }

    /**
     *  This is the starting point for responding to a new session.
     */
    public void startIncoming() {

        //updatePacketListener();
    }

    /**
     * When we initiate a session we need to start a bunch of negotiators right after we receive the result
     * packet for our session-initiate.  This is where we start them.
     * 
     */
    private void startNegotiators() {

        for (ContentNegotiator contentNegotiator : contentNegotiators) {
            TransportNegotiator transNeg = contentNegotiator.getTransportNegotiator();
            transNeg.start();
        }
    }
    
    /**
     * The jingle session may have one or more media managers that are trying to establish media sessions.
     * When the media manager succeeds in creating a media session is registers it with the session by the
     * media manager's static name.  This routine is where the media manager does the registering.
     */
    public void addJingleMediaSession(String mediaManagerName, JingleMediaSession mediaSession) {
        mediaSessionMap.put(mediaManagerName, mediaSession);
    }
    
    /**
     * The jingle session may have one or more media managers that are trying to establish media sessions.
     * When the media manager succeeds in creating a media session is registers it with the session by the
     * media manager's static name. This routine is where other objects can access the registered media sessions.
     * NB: If the media manager has not succeeded in establishing a media session then this could return null.
     */
    public JingleMediaSession getMediaSession(String mediaManagerName) {
        return mediaSessionMap.get(mediaManagerName);
    }
}
