/*
 * The Apache Software License, Version 1.1
 *
 *
 * Copyright (c) 2001-2003 The Apache Software Foundation.  All rights
 * reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 *
 * 3. The end-user documentation included with the redistribution,
 *    if any, must include the following acknowledgment:
 *       "This product includes software developed by the
 *        Apache Software Foundation (http://www.apache.org/)."
 *    Alternately, this acknowledgment may appear in the software itself,
 *    if and wherever such third-party acknowledgments normally appear.
 *
 * 4. The names "Axis" and "Apache Software Foundation" must
 *    not be used to endorse or promote products derived from this
 *    software without prior written permission. For written
 *    permission, please contact apache@apache.org.
 *
 * 5. Products derived from this software may not be called "Apache",
 *    nor may "Apache" appear in their name, without prior written
 *    permission of the Apache Software Foundation.
 *
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 * ====================================================================
 *
 * This software consists of voluntary contributions made by many
 * individuals on behalf of the Apache Software Foundation.  For more
 * information on the Apache Software Foundation, please see
 * <http://www.apache.org/>.
 */

package org.apache.axis.encoding.ser;

import org.apache.axis.components.logger.LogFactory;
import org.apache.axis.encoding.DeserializationContext;
import org.apache.axis.encoding.Deserializer;
import org.apache.axis.encoding.DeserializerImpl;
import org.apache.axis.encoding.DeserializerTarget;
import org.apache.axis.message.SOAPHandler;
import org.apache.axis.utils.Messages;
import org.apache.commons.logging.Log;
import org.xml.sax.Attributes;
import org.xml.sax.SAXException;

import javax.xml.namespace.QName;
import java.util.HashMap;
import java.util.Map;

/*
 * A <code>MapSerializer</code> is be used to deserialize
 * deserialize Maps using the <code>SOAP-ENC</code>
 * encoding style.<p>
 * 
 * @author Glen Daniels (gdaniels@macromedia.com)
 * Modified by @author Rich scheuerle <scheu@us.ibm.com>
 */

public class MapDeserializer extends DeserializerImpl
{

   private static Log log =
           LogFactory.getLog(MapDeserializer.class.getName());

   // Fixed objects to act as hints to the set() callback
   public static final Object KEYHINT = new Object();
   public static final Object VALHINT = new Object();
   public static final Object NILHINT = new Object();


   /**
    * This method is invoked after startElement when the element requires
    * deserialization (i.e. the element is not an href and the value is not nil.)
    * <p/>
    * Simply creates map.
    *
    * @param namespace  is the namespace of the element
    * @param localName  is the name of the element
    * @param prefix     is the prefix of the element
    * @param attributes are the attributes on the element...used to get the type
    * @param context    is the DeserializationContext
    */
   public void onStartElement(String namespace, String localName,
                              String prefix, Attributes attributes,
                              DeserializationContext context)
           throws SAXException
   {
      if (log.isDebugEnabled())
      {
         log.debug("Enter MapDeserializer::startElement()");
      }

      if (context.isNil(attributes))
      {
         return;
      }

      // Create a hashmap to hold the deserialized values.
      setValue(new HashMap());

      if (log.isDebugEnabled())
      {
         log.debug("Exit: MapDeserializer::startElement()");
      }
   }

   /**
    * onStartChild is called on each child element.
    *
    * @param namespace  is the namespace of the child element
    * @param localName  is the local name of the child element
    * @param prefix     is the prefix used on the name of the child element
    * @param attributes are the attributes of the child element
    * @param context    is the deserialization context.
    * @return is a Deserializer to use to deserialize a child (must be
    *         a derived class of SOAPHandler) or null if no deserialization should
    *         be performed.
    */
   public SOAPHandler onStartChild(String namespace,
                                   String localName,
                                   String prefix,
                                   Attributes attributes,
                                   DeserializationContext context)
           throws SAXException
   {

      if (log.isDebugEnabled())
      {
         log.debug("Enter: MapDeserializer::onStartChild()");
      }

      if (localName.equals("item"))
      {
         ItemHandler handler = new ItemHandler(this);

         // This item must be complete before we're complete...
         addChildDeserializer(handler);

         if (log.isDebugEnabled())
         {
            log.debug("Exit: MapDeserializer::onStartChild()");
         }

         return handler;
      }

      return this;
   }

   /**
    * The registerValueTarget code above causes this set function to be invoked when
    * each value is known.
    *
    * @param value is the value of an element
    * @param hint  is the key
    */
   public void setChildValue(Object value, Object hint) throws SAXException
   {
      if (log.isDebugEnabled())
      {
         log.debug(Messages.getMessage("gotValue00", "MapDeserializer", "" + value));
      }
      ((Map)this.value).put(hint, value);
   }

   /**
    * A deserializer for an <item>.  Handles getting the key and
    * value objects from their own deserializers, and then putting
    * the values into the HashMap we're building.
    */
   class ItemHandler extends DeserializerImpl
   {
      Object key;
      Object myValue;
      int numSet = 0;
      MapDeserializer md = null;

      ItemHandler(MapDeserializer md)
      {
         this.md = md;
      }

      /**
       * Callback from our deserializers.  The hint indicates
       * whether the passed "val" argument is the key or the value
       * for this mapping.
       */
      public void setChildValue(Object val, Object hint) throws SAXException
      {
         if (hint == KEYHINT)
         {
            key = val;
         }
         else if (hint == VALHINT)
         {
            myValue = val;
         }
         else if (hint != NILHINT)
         {
            return;
         }
         numSet++;
         if (numSet == 2)
            md.setChildValue(myValue, key);
      }

      public SOAPHandler onStartChild(String namespace,
                                      String localName,
                                      String prefix,
                                      Attributes attributes,
                                      DeserializationContext context)
              throws SAXException
      {
         QName typeQName = context.getTypeFromAttributes(namespace,
                 localName,
                 attributes);
         Deserializer dser = context.getDeserializerForType(typeQName);

         // If no deserializer, use the base DeserializerImpl.
         if (dser == null)
            dser = new DeserializerImpl();

         // When the child value is ready, we
         // want our set method to be invoked.
         // To do this register a DeserializeTarget on the
         // new Deserializer.
         DeserializerTarget dt = null;
         if (context.isNil(attributes))
         {
            dt = new DeserializerTarget(this, NILHINT);
         }
         else if (localName.equals("key"))
         {
            dt = new DeserializerTarget(this, KEYHINT);
         }
         else if (localName.equals("value"))
         {
            dt = new DeserializerTarget(this, VALHINT);
         }
         else
         {
            // Do nothing
         }
         if (dt != null)
         {
            dser.registerValueTarget(dt);
         }

         // We need this guy to complete for us to complete.
         addChildDeserializer(dser);

         return (SOAPHandler)dser;
      }
   }
}
