//
   //  ========================================================================
   //  Copyright (c) 1995-2016 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.jsr356;
  
  import java.util.ArrayList;
  import java.util.List;
  import java.util.Map;
  import java.util.concurrent.ConcurrentHashMap;
  
  import javax.websocket.MessageHandler;
  
  import org.eclipse.jetty.util.log.Log;
  import org.eclipse.jetty.util.log.Logger;
  import org.eclipse.jetty.websocket.common.util.ReflectUtils;
  import org.eclipse.jetty.websocket.jsr356.metadata.MessageHandlerMetadata;
  
  /**
   * Factory for {@link MessageHandlerMetadata}
   */
  public class MessageHandlerFactory
  {
      private static final Logger LOG = Log.getLogger(MessageHandlerFactory.class);
      /** Registered MessageHandlers at this level */
      private Map<Class<? extends MessageHandler>, List<MessageHandlerMetadata>> registered;
  
      public MessageHandlerFactory()
      {
          registered = new ConcurrentHashMap<>();
      }
  
      public List<MessageHandlerMetadata> getMetadata(Class<? extends MessageHandler> handler) throws IllegalStateException
      {
          if (LOG.isDebugEnabled())
          {
              LOG.debug("getMetadata({})",handler);
          }
          List<MessageHandlerMetadata> ret = registered.get(handler);
          if (ret != null)
          {
              return ret;
          }
  
          return register(handler);
      }
  
      public List<MessageHandlerMetadata> register(Class<? extends MessageHandler> handler)
      {
          List<MessageHandlerMetadata> metadatas = new ArrayList<>();
  
          boolean partial = false;
  
          if (MessageHandler.Partial.class.isAssignableFrom(handler))
          {
              if (LOG.isDebugEnabled())
              {
                  LOG.debug("supports Partial: {}",handler);
              }
              partial = true;
              Class<?> onMessageClass = ReflectUtils.findGenericClassFor(handler,MessageHandler.Partial.class);
              if (LOG.isDebugEnabled())
              {
                  LOG.debug("Partial message class: {}",onMessageClass);
              }
              metadatas.add(new MessageHandlerMetadata(handler,onMessageClass,partial));
          }
  
          if (MessageHandler.Whole.class.isAssignableFrom(handler))
          {
              if (LOG.isDebugEnabled())
              {
                  LOG.debug("supports Whole: {}",handler.getName());
              }
              partial = false;
              Class<?> onMessageClass = ReflectUtils.findGenericClassFor(handler,MessageHandler.Whole.class);
              if (LOG.isDebugEnabled())
              {
                  LOG.debug("Whole message class: {}",onMessageClass);
              }
              metadatas.add(new MessageHandlerMetadata(handler,onMessageClass,partial));
          }
  
          registered.put(handler,metadatas);
          return metadatas;
     }
 }