/*

  * Copyright 2006-2011 The Kuali Foundation

  *

  * Licensed under the Educational Community 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.opensource.org/licenses/ecl2.php

  *

  * 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.kuali.rice.core.impl.style;

 import java.io.StringReader;

 import java.util.List;

 import java.util.Properties;

 import javax.xml.transform.Templates;

 import javax.xml.transform.TransformerConfigurationException;

 import javax.xml.transform.TransformerFactory;

 import javax.xml.transform.stream.StreamSource;

 import org.apache.log4j.Logger;

 import org.kuali.rice.core.api.style.Style;

 import org.kuali.rice.core.api.style.StyleRepositoryService;

 import org.kuali.rice.core.api.style.StyleService;

 import org.kuali.rice.core.framework.services.CoreFrameworkServiceLocator;

 import org.kuali.rice.kew.util.KEWConstants;

 import org.kuali.rice.krad.util.KRADConstants;

 import org.kuali.rice.ksb.api.cache.RiceCacheAdministrator;

 /**

  * Implements generic StyleService via existing EDL style table

  * @author Kuali Rice Team (rice.collab@kuali.org)

  */

 public class StyleServiceImpl implements StyleService {

     private static final Logger LOG = Logger.getLogger(StyleServiceImpl.class);

     private StyleRepositoryService styleRepositoryService;

     private RiceCacheAdministrator cache;

     public void setStyleRepositoryService(StyleRepositoryService styleRepositoryService) {

             this.styleRepositoryService = styleRepositoryService;

     }

     public void setCache(RiceCacheAdministrator cache) {

             this.cache = cache;

     }

     /**

      * Loads the named style from the database, or (if configured) imports it from a file

      * specified via a configuration parameter with a name of the format edl.style.<styleName>

      * {@inheritDoc}

      * @see org.kuali.rice.edl.impl.service.StyleService#getStyle(java.lang.String)

      */

     @Override

     public Style getStyle(String styleName) {

             // TODO should really be caching here!

             return styleRepositoryService.getStyle(styleName);

     }

     @Override

     public Templates getStyleAsTranslet(String name) throws TransformerConfigurationException {

         if (name == null) return null;

         Templates translet = fetchTemplatesFromCache(name);

         if (translet == null) {

             Style style = getStyle(name);

             if (style == null) {

                 return null;

             }

             boolean useXSLTC = CoreFrameworkServiceLocator.getParameterService().getParameterValueAsBoolean(KEWConstants.KEW_NAMESPACE, KRADConstants.DetailTypes.EDOC_LITE_DETAIL_TYPE, KEWConstants.EDL_USE_XSLTC_IND);

             if (useXSLTC) {

                 LOG.info("using xsltc to compile stylesheet");

                 String key = "javax.xml.transform.TransformerFactory";

                 String value = "org.apache.xalan.xsltc.trax.TransformerFactoryImpl";

                 Properties props = System.getProperties();

                 props.put(key, value);

                 System.setProperties(props);

             }

             TransformerFactory factory = TransformerFactory.newInstance();

             factory.setURIResolver(new StyleUriResolver(this));

             if (useXSLTC) {

                 factory.setAttribute("translet-name",name);

                 factory.setAttribute("generate-translet",Boolean.TRUE);

                 String debugTransform = CoreFrameworkServiceLocator.getParameterService().getParameterValueAsString(KEWConstants.KEW_NAMESPACE, KRADConstants.DetailTypes.EDOC_LITE_DETAIL_TYPE, KEWConstants.EDL_DEBUG_TRANSFORM_IND);

                 if (debugTransform.trim().equals("Y")) {

                     factory.setAttribute("debug", Boolean.TRUE);

                 }

             }

             translet = factory.newTemplates(new StreamSource(new StringReader(style.getXmlContent())));

             putTemplatesInCache(name, translet);

         }

         return translet;

     }

     @Override

     public void saveStyle(Style style) {

             styleRepositoryService.saveStyle(style);

     }

     @Override

     public List<String> getAllStyleNames() {

         return styleRepositoryService.getAllStyleNames();

     }

     // cache helper methods

     /**

      * Returns the key to be used for caching the Templates for the given style name.

      */

     protected String getTemplatesCacheKey(String styleName) {

         return StyleRepositoryServiceImpl.TEMPLATES_CACHE_GROUP_NAME + ":" + styleName;

     }

     protected Templates fetchTemplatesFromCache(String styleName) {

         return (Templates) cache.getFromCache(getTemplatesCacheKey(styleName));

     }

     protected void putTemplatesInCache(String styleName, Templates templates) {

         cache.putInCache(getTemplatesCacheKey(styleName), templates, StyleRepositoryServiceImpl.TEMPLATES_CACHE_GROUP_NAME);

     }

 }