/*
    * 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;
  
  /**
   * The default downstream {@link ChannelStateEvent} implementation.
   */
  public class DownstreamChannelStateEvent implements ChannelStateEvent {
  
      private final Channel channel;
      private final ChannelFuture future;
      private final ChannelState state;
      private final Object value;
  
      /**
       * Creates a new instance.
       */
      public DownstreamChannelStateEvent(
              Channel channel, ChannelFuture future,
              ChannelState state, Object value) {
  
          if (channel == null) {
              throw new NullPointerException("channel");
          }
          if (future == null) {
              throw new NullPointerException("future");
          }
          if (state == null) {
              throw new NullPointerException("state");
          }
          this.channel = channel;
          this.future = future;
          this.state = state;
          this.value = value;
      }
  
      public Channel getChannel() {
          return channel;
      }
  
      public ChannelFuture getFuture() {
          return future;
      }
  
      public ChannelState getState() {
          return state;
      }
  
      public Object getValue() {
          return value;
      }
  
      @Override
      public String toString() {
          String channelString = getChannel().toString();
          StringBuilder buf = new StringBuilder(channelString.length() + 64);
          buf.append(channelString);
          switch (getState()) {
          case OPEN:
              if (Boolean.TRUE.equals(getValue())) {
                  buf.append(" OPEN");
              } else {
                  buf.append(" CLOSE");
              }
              break;
          case BOUND:
              if (getValue() != null) {
                  buf.append(" BIND: ");
                  buf.append(getValue());
              } else {
                  buf.append(" UNBIND");
              }
              break;
          case CONNECTED:
              if (getValue() != null) {
                  buf.append(" CONNECT: ");
                  buf.append(getValue());
              } else {
                  buf.append(" DISCONNECT");
              }
              break;
          case INTEREST_OPS:
              buf.append(" CHANGE_INTEREST: ");
              buf.append(getValue());
              break;
          default:
             buf.append(' ');
             buf.append(getState().name());
             buf.append(": ");
             buf.append(getValue());
         }
         return buf.toString();
     }
 }