/**
      This file is part of GoldenGate Project (named also GoldenGate or GG).
   
      Copyright 2009, Frederic Bregier, and individual contributors by the @author
      tags. See the COPYRIGHT.txt in the distribution for a full listing of
      individual contributors.
   
      All GoldenGate Project 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.
  
     GoldenGate 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 GoldenGate .  If not, see <http://www.gnu.org/licenses/>.
   */
  package openr66.protocol.networkhandler;
  
  import java.util.concurrent.ConcurrentLinkedQueue;
  import java.util.concurrent.atomic.AtomicInteger;
  
  import openr66.protocol.exception.OpenR66ProtocolRemoteShutdownException;
  
  import org.jboss.netty.channel.Channel;
  import org.jboss.netty.channel.Channels;
  
  /**
   * NetworkChannel object to keep Network channel open while some local channels
   * are attached to it.
   *
   * @author Frederic Bregier
   *
   */
  public class NetworkChannel {
      /**
       * Number of active Local Channel referencing this Network Channel
       */
      public volatile AtomicInteger count = new AtomicInteger(1);
      /**
       * Does this Network Channel is in shutdown
       */
      public volatile boolean isShuttingDown = false;
      /**
       * Associated LocalChannel
       */
      public ConcurrentLinkedQueue<Channel> localChannels =
          new ConcurrentLinkedQueue<Channel>();
      /**
       * Network Channel
       */
      public final Channel channel;
      /**
       * Last Time in ms this channel was used by a LocalChannel
       */
      public long lastTimeUsed;
      
      public NetworkChannel(Channel networkChannel) {
          this.channel = networkChannel;
      }
  
      synchronized public void add(Channel localChannel)
      throws OpenR66ProtocolRemoteShutdownException {
          if (isShuttingDown) {
              throw new OpenR66ProtocolRemoteShutdownException("Current NetworkChannel is closed");
          }
          lastTimeUsed = System.currentTimeMillis();
          localChannels.add(localChannel);
      }
  
      synchronized public void remove(Channel localChannel) {
          if (localChannel.isConnected()) {
              Channels.close(localChannel);
          }
          localChannels.remove(localChannel);
      }
  
      synchronized public void shutdownAllLocalChannels() {
          isShuttingDown = true;
          count.set(0);
          Channel localChannel = localChannels.poll();
          while (localChannel != null) {
              Channels.close(localChannel);
              localChannel = localChannels.poll();
          }
      }
      @Override
      public String toString() {
          return "NC: " + channel.isConnected() + " " +
                  channel.getRemoteAddress() + " Count: " + count;
      }
  
      /* (non-Javadoc)
       * @see java.lang.Object#equals(java.lang.Object)
       */
      @Override
     public boolean equals(Object obj) {
         if (obj instanceof NetworkChannel) {
             NetworkChannel obj2 = (NetworkChannel) obj;
             return (obj2.channel.getId() == this.channel.getId());
         }
         return false;
     }
 
     /* (non-Javadoc)
      * @see java.lang.Object#hashCode()
      */
     @Override
     public int hashCode() {
         return this.channel.getId();
     }
 
 }