/*

  *   SONEWS News Server

  *   see AUTHORS for the list of contributors

  *

  *   This program is free software: you can redistribute it and/or modify

  *   it under the terms of the GNU General Public License as published by

  *   the Free Software Foundation, either version 3 of the License, or

  *   (at your option) any later version.

  *

  *   This program 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 General Public License for more details.

  *

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

  *   along with this program.  If not, see <http://www.gnu.org/licenses/>.

  */

 package org.sonews.daemon;

 import org.sonews.util.Log;

 import java.nio.ByteBuffer;

 import java.nio.channels.SocketChannel;

 import java.util.concurrent.ArrayBlockingQueue;

 /**

  * Does most of the work: parsing input, talking to client and Database.

  * @author Christian Lins

  * @since sonews/0.5.0

  */

 class ConnectionWorker extends AbstractDaemon

 {

 	// 256 pending events should be enough

 	private static ArrayBlockingQueue<SocketChannel> pendingChannels = new ArrayBlockingQueue<SocketChannel>(256, true);

 	/**

 	 * Registers the given channel for further event processing.

 	 * @param channel

 	 */

 	public static void addChannel(SocketChannel channel)

 		throws InterruptedException

 	{

 		pendingChannels.put(channel);

 	}

 	/**

 	 * Processing loop.

 	 */

 	@Override

 	public void run()

 	{

 		while (isRunning()) {

 			try {

 				// Retrieve and remove if available, otherwise wait.

 				SocketChannel channel = pendingChannels.take();

 				if (channel != null) {

 					// Connections.getInstance().get() MAY return null

 					NNTPConnection conn = Connections.getInstance().get(channel);

 					// Try to lock the connection object

 					if (conn != null && conn.tryReadLock()) {

 						ByteBuffer buf = conn.getBuffers().nextInputLine();

 						while (buf != null) // Complete line was received

 						{

 							final byte[] line = new byte[buf.limit()];

 							buf.get(line);

 							ChannelLineBuffers.recycleBuffer(buf);

 							// Here is the actual work done

 							conn.lineReceived(line);

 							// Read next line as we could have already received the next line

 							buf = conn.getBuffers().nextInputLine();

 						}

 						conn.unlockReadLock();

 					} else {

 						addChannel(channel);

 					}

 				}

 			} catch (InterruptedException ex) {

 				Log.get().info("ConnectionWorker interrupted: " + ex);

 			} catch (Exception ex) {

 				Log.get().severe("Exception in ConnectionWorker: " + ex);

 				ex.printStackTrace();

 			}

 		} // end while(isRunning())

 	}

 }