/**

 * Java RTP Library (jlibrtp)

 * Copyright (C) 2006 Arne Kepp

 * 

 * This library is free software; you can redistribute it and/or

 * modify it under the terms of the GNU Lesser General Public

 * License as published by the Free Software Foundation; either

 * version 2.1 of the License, or (at your option) any later version.

 *

 * This library is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

 * Lesser General Public License for more details.

 * 

 * You should have received a copy of the GNU Lesser General Public

 * License along with this library; if not, write to the Free Software

 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA

 */

package jlibrtp;

import java.util.Enumeration;

/**

 * The purpose of this thread is to check whether there are packets ready from 

 * any participants.

 * 

 * It should sleep when not in use, and be woken up by a condition variable.

 * 

 * Optionally, if we do jitter-control, the condition variable should have a max waiting period 

 * equal to how often we need to push data.

 * 

 * @author Arne Kepp

 */

public class AppCallerThread extends Thread {

	/**  The parent RTP Session */

	RTPSession rtpSession;

	/**  The applications interface, where the callback methods are called */

	RTPAppIntf appl;

	/**

	 * Instatiates the AppCallerThread

	 * 

	 * @param session the RTPSession with participants etc

	 * @param rtpApp the interface to which data is given

	 */

	protected AppCallerThread(RTPSession session, RTPAppIntf rtpApp) {

		rtpSession = session;

		appl = rtpApp;

		if(RTPSession.rtpDebugLevel > 1) {

			System.out.println("<-> AppCallerThread created");

		}  

	}

	/**

	 * The AppCallerThread will run in this loop until the RTPSession

	 * is terminated.

	 * 

	 * Whenever an RTP packet is received it will loop over the

	 * participants to check for packet buffers that have available

	 * frame.

	 */

	public void run() {

		if(RTPSession.rtpDebugLevel > 3) {

			System.out.println("-> AppCallerThread.run()");

		}

		while(rtpSession.endSession == false) {

			rtpSession.pktBufLock.lock();

		    try {

				if(RTPSession.rtpDebugLevel > 4) {

					System.out.println("<-> AppCallerThread going to Sleep");

				}

				try { rtpSession.pktBufDataReady.await(); } 

					catch (Exception e) { System.out.println("AppCallerThread:" + e.getMessage());}

		    	// Next loop over all participants and check whether they have anything for us.

				Enumeration<Participant> enu = rtpSession.partDb.getParticipants();

				while(enu.hasMoreElements()) {

					Participant p = enu.nextElement(); 

					boolean done = false;

					//System.out.println(p.ssrc + " " + !done +" " + p.rtpAddress 

					//		+ " " + rtpSession.naiveReception + " " + p.pktBuffer);

					//System.out.println("done: " + done + "  p.unexpected: " + p.unexpected);

					while(!done && (!p.unexpected || rtpSession.naiveReception) 

							&& p.pktBuffer != null && p.pktBuffer.length > 0) {

						DataFrame aFrame = p.pktBuffer.popOldestFrame();

						if(aFrame == null) {

							done = true;

						} else {

							appl.receiveData(aFrame, p);

						}

					}

				}

		     } finally {

		       rtpSession.pktBufLock.unlock();

		     }

		}

		if(RTPSession.rtpDebugLevel > 3) {

			System.out.println("<- AppCallerThread.run() terminating");

		}  

	}

}