//
   //  ========================================================================
   //  Copyright (c) 1995-2012 Mort Bay Consulting Pty. Ltd.
   //  ------------------------------------------------------------------------
   //  All rights reserved. This program and the accompanying materials
   //  are made available under the terms of the Eclipse Public License v1.0
   //  and Apache License v2.0 which accompanies this distribution.
   //
   //      The Eclipse Public License is available at
  //      http://www.eclipse.org/legal/epl-v10.html
  //
  //      The Apache License v2.0 is available at
  //      http://www.opensource.org/licenses/apache2.0.php
  //
  //  You may elect to redistribute this code under either of these licenses.
  //  ========================================================================
  //
  
  package org.eclipse.jetty.websocket.common.extensions;
  
  import org.eclipse.jetty.io.ByteBufferPool;
  import org.eclipse.jetty.util.StringUtil;
  import org.eclipse.jetty.websocket.api.WebSocketException;
  import org.eclipse.jetty.websocket.api.WebSocketPolicy;
  import org.eclipse.jetty.websocket.api.extensions.Extension;
  import org.eclipse.jetty.websocket.api.extensions.ExtensionConfig;
  import org.eclipse.jetty.websocket.api.extensions.ExtensionFactory;
  import org.eclipse.jetty.websocket.common.extensions.compress.FrameCompressionExtension;
  import org.eclipse.jetty.websocket.common.extensions.compress.MessageCompressionExtension;
  import org.eclipse.jetty.websocket.common.extensions.fragment.FragmentExtension;
  import org.eclipse.jetty.websocket.common.extensions.identity.IdentityExtension;
  
  public class WebSocketExtensionFactory extends ExtensionFactory
  {
      private WebSocketPolicy policy;
      private ByteBufferPool bufferPool;
  
      public WebSocketExtensionFactory(WebSocketPolicy policy, ByteBufferPool bufferPool)
      {
          super();
          this.policy = policy;
          this.bufferPool = bufferPool;
  
          register("identity",IdentityExtension.class);
          register("fragment",FragmentExtension.class);
          register("x-webkit-deflate-frame",FrameCompressionExtension.class);
          register("permessage-compress",MessageCompressionExtension.class);
      }
  
      @Override
      public Extension newInstance(ExtensionConfig config)
      {
          if (config == null)
          {
              return null;
          }
  
          String name = config.getName();
          if (StringUtil.isBlank(name))
          {
              return null;
          }
  
          Class<? extends Extension> extClass = getExtension(name);
          if (extClass == null)
          {
              return null;
          }
  
          try
          {
              Extension ext = extClass.newInstance();
              if (ext instanceof AbstractExtension)
              {
                  AbstractExtension aext = (AbstractExtension)ext;
                  aext.setConfig(config);
                  aext.setPolicy(policy);
                  aext.setBufferPool(bufferPool);
              }
              return ext;
          }
          catch (InstantiationException | IllegalAccessException e)
          {
              throw new WebSocketException("Cannot instantiate extension: " + extClass,e);
          }
      }
  }