/*
    * Copyright 2012 The Netty Project
    *
    * The Netty Project licenses this file to you under the Apache License,
    * version 2.0 (the "License"); you may not use this file except in compliance
    * with the License. You may obtain a copy of the License at:
    *
    *   http://www.apache.org/licenses/LICENSE-2.0
    *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
   * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
   * License for the specific language governing permissions and limitations
   * under the License.
   */
  package org.jboss.netty.channel.local;
  
  import static org.jboss.netty.channel.Channels.*;
  
  import org.jboss.netty.channel.AbstractChannelSink;
  import org.jboss.netty.channel.Channel;
  import org.jboss.netty.channel.ChannelEvent;
  import org.jboss.netty.channel.ChannelException;
  import org.jboss.netty.channel.ChannelFuture;
  import org.jboss.netty.channel.ChannelPipeline;
  import org.jboss.netty.channel.ChannelState;
  import org.jboss.netty.channel.ChannelStateEvent;
  import org.jboss.netty.channel.MessageEvent;
  
  final class LocalServerChannelSink extends AbstractChannelSink {
  
      public void eventSunk(ChannelPipeline pipeline, ChannelEvent e) throws Exception {
          Channel channel = e.getChannel();
          if (channel instanceof DefaultLocalServerChannel) {
              handleServerChannel(e);
          } else if (channel instanceof DefaultLocalChannel) {
              handleAcceptedChannel(e);
          }
      }
  
      private static void handleServerChannel(ChannelEvent e) {
          if (!(e instanceof ChannelStateEvent)) {
              return;
          }
  
          ChannelStateEvent event = (ChannelStateEvent) e;
          DefaultLocalServerChannel channel =
                (DefaultLocalServerChannel) event.getChannel();
          ChannelFuture future = event.getFuture();
          ChannelState state = event.getState();
          Object value = event.getValue();
          switch (state) {
          case OPEN:
              if (Boolean.FALSE.equals(value)) {
                  close(channel, future);
              }
              break;
          case BOUND:
              if (value != null) {
                  bind(channel, future, (LocalAddress) value);
              } else {
                  close(channel, future);
              }
              break;
          }
      }
  
      private static void handleAcceptedChannel(ChannelEvent e) {
          if (e instanceof ChannelStateEvent) {
              ChannelStateEvent event = (ChannelStateEvent) e;
              DefaultLocalChannel channel = (DefaultLocalChannel) event.getChannel();
              ChannelFuture future = event.getFuture();
              ChannelState state = event.getState();
              Object value = event.getValue();
  
              switch (state) {
              case OPEN:
                  if (Boolean.FALSE.equals(value)) {
                      channel.closeNow(future);
                  }
                  break;
              case BOUND:
              case CONNECTED:
                  if (value == null) {
                      channel.closeNow(future);
                  }
                  break;
              case INTEREST_OPS:
                  // Unsupported - discard silently.
                  future.setSuccess();
                  break;
              }
          } else if (e instanceof MessageEvent) {
              MessageEvent event = (MessageEvent) e;
              DefaultLocalChannel channel = (DefaultLocalChannel) event.getChannel();
              boolean offered = channel.writeBuffer.offer(event);
              assert offered;
              channel.flushWriteBuffer();
          }
     }
 
     private static void bind(DefaultLocalServerChannel channel, ChannelFuture future, LocalAddress localAddress) {
         try {
             if (!LocalChannelRegistry.register(localAddress, channel)) {
                 throw new ChannelException("address already in use: " + localAddress);
             }
             if (!channel.bound.compareAndSet(false, true)) {
                 throw new ChannelException("already bound");
             }
 
             channel.localAddress = localAddress;
             future.setSuccess();
             fireChannelBound(channel, localAddress);
         } catch (Throwable t) {
             LocalChannelRegistry.unregister(localAddress);
             future.setFailure(t);
             fireExceptionCaught(channel, t);
         }
     }
 
     private static void close(DefaultLocalServerChannel channel, ChannelFuture future) {
         try {
             if (channel.setClosed()) {
                 future.setSuccess();
                 LocalAddress localAddress = channel.localAddress;
                 if (channel.bound.compareAndSet(true, false)) {
                     channel.localAddress = null;
                     LocalChannelRegistry.unregister(localAddress);
                     fireChannelUnbound(channel);
                 }
                 fireChannelClosed(channel);
             } else {
                 future.setSuccess();
             }
         } catch (Throwable t) {
             future.setFailure(t);
             fireExceptionCaught(channel, t);
         }
     }
 }