/*

  * ============================================================================

  *

  *  File:     WsSpace.java

  *----------------------------------------------------------------------------

  *

  * Copyright 2008 Erlend Nossum

  *

  * Licensed 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.

  *

  *  Description:  See javadoc below

  *

  *  Created:      Mar 4, 2008

  * ============================================================================ 

  */

 package org.semispace.ws;

 import java.io.StringReader;

 import java.util.HashMap;

 import java.util.Map;

 import javax.jws.WebService;

 import javax.xml.parsers.DocumentBuilderFactory;

 import org.slf4j.Logger;

 import org.slf4j.LoggerFactory;

 import org.semispace.Holder;

 import org.semispace.SemiSpace;

 import org.w3c.dom.Document;

 import org.w3c.dom.Node;

 import org.w3c.dom.NodeList;

 import org.xml.sax.InputSource;

 /**

  * Implementation of unauthenticated space access.

  *  <p>

  * You need to set the space.

  * </p>

  */

 @WebService(endpointInterface = "org.semispace.ws.WsSpace")

 public class WsSpaceImpl implements WsSpace {

     private static final Logger log = LoggerFactory.getLogger(WsSpaceImpl.class);

     private SemiSpace space;

     /** For the benefit of spring */

     public void setSpace(SemiSpace space) {

         this.space = space;

     }

     public void write(String contents, long timeToLiveMs) {

         makeSureSpaceIsPresent();

         Holder elem = retrievePropertiesFromXml(contents);

         space.writeToElements(elem.getClassName(),timeToLiveMs, elem.getXml(), elem.getSearchMap());

     }

     private void makeSureSpaceIsPresent() {

         if ( space == null ) {

             String error = "Erroneous initialization - need space.";

             log.error(error);

             throw new RuntimeException(error);

         }

     }

     public String read(String template, long queryLifeMs) {

         makeSureSpaceIsPresent();

         Holder elem = retrievePropertiesFromXml(template );

         String found = space.findOrWaitLeaseForTemplate(elem.getSearchMap(), queryLifeMs, false);

         return found;

     }

     public String readIfExists(String template) {

         makeSureSpaceIsPresent();

         return read( template, 0);

     }

     public String take(String template, long queryLifeMs) {

         makeSureSpaceIsPresent();

         Holder elem = retrievePropertiesFromXml(template );

         String found = space.findOrWaitLeaseForTemplate(elem.getSearchMap(), queryLifeMs, true);

         return found;

     }

     public String takeIfExists(String template) {

         makeSureSpaceIsPresent();

         return take( template, 0);

     }

     /**

      * Protected for the benefit of junit test(s)

      * @return A <b>temporary</b> holder object containing the relevant elements found in the source.

      * @see WsSpaceImpl#retrievePropertiesFromObject

      */

     protected Holder retrievePropertiesFromXml(String xmlsource) {

         // InputStream is = new StringConverterBufferedInputStream( new FileInputStream( tmpfile ) );

         InputSource is = new InputSource( new StringReader(xmlsource));

         DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();

         Document doc = null;

         try {

             doc = factory.newDocumentBuilder().parse( is );

         } catch (Exception e) {

             log.error("Returning null, due to exception parsing xml: "+xmlsource, e);

             return null;

         }

         String doctype = doc.getDocumentElement().getNodeName();

         Map<String, String> map = new HashMap<String, String>();

         NodeList children = doc.getDocumentElement().getChildNodes();

         for ( int i=0 ; i < children.getLength() ; i++) {

             Node node = children.item( i );

             //log.info("Got node "+node.getNodeName()+" which contains "+node.getNodeValue());

             if ( node.getNodeType() == Node.ELEMENT_NODE && node.getChildNodes().getLength() > 0) {

                 String name = node.getNodeName();

                 String value = node.getChildNodes().item(0).getNodeValue();

                 //log.info("This is an element node with "+node.getChildNodes().getLength()+" children which is "+value);

                 if( value != null ) {

                     map.put(name,value);

                 }

             }

         }

         map.put("class", doctype);

         Holder holder = new Holder(xmlsource, -1, doctype, -1, map );

         return holder;

     }

 }