/*
    * Copyright 2000-2004 The Apache Software Foundation.
    * 
    * 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.
   */
  
  package org.apache.jetspeed.portal.portlets;
  
  //Element Construction Set
  import org.apache.ecs.ConcreteElement;
  
  //Jetspeed stuff
  import org.apache.jetspeed.portal.PortletConfig;
  import org.apache.jetspeed.portal.PortletException;
  import org.apache.jetspeed.util.JetspeedClearElement;
  import org.apache.jetspeed.util.SimpleTransform;
  import org.apache.jetspeed.cache.disk.JetspeedDiskCache;
  import org.apache.jetspeed.services.logging.JetspeedLogFactoryService;
  import org.apache.jetspeed.services.logging.JetspeedLogger;
  import org.apache.jetspeed.services.resources.JetspeedResources;
  
  
  //XML stuff
  import org.xml.sax.SAXException;
  
  //java stuff
  import java.io.IOException;
  
  
  /***
  Provides a content publication system (like Slashdot).
  
  @author <a href="mailto:burton@apache.org">Kevin A. Burton</a>
  @version $Id: JetspeedContent.java,v 1.26 2004/02/23 04:03:34 jford Exp $ 
  */
  public class JetspeedContent extends FileWatchPortlet 
  {
  
      /***
       * Static initialization of the logger for this class
       */    
      private static final JetspeedLogger logger = JetspeedLogFactoryService.getLogger(JetspeedContent.class.getName());
      
      public static final String PROVIDER_NAME_KEY = "provider-name";
  
      /***
      The name of the JPC provider.
      */
      private String provider = "";
  
      /***
      The stylesheet for using with this provider
      */
      private String stylesheet = "";
  
      /***
      The url that was specified by the provider
      */
      private String url = null;
      
      /***
      Return the last time the provider's URL has been changed.
      */
      private long lastModified;
      
      
      /***
      Init this Portlet, set it's title, description, etc.
      */
      public void init() throws PortletException {
  
          PortletConfig config = this.getPortletConfig();
          
          provider = config.getInitParameter( PROVIDER_NAME_KEY );
          
          if ( provider == null ) {
              throw new PortletException( "You need to specify " + PROVIDER_NAME_KEY );
          }
  
          //NOTE:  There are no HARD keys here in JetspeedResources.  If you change
          //this format of this it will break at runtime.  CAREFULL!
          
          this.url = JetspeedResources.getString( "content.provider." + provider + ".url" );
          
          this.stylesheet = JetspeedResources.getString( "content.provider." + provider + ".stylesheet.url" );
          
          String title = JetspeedResources.getString( "content.provider." + provider + ".title" );
  
          String description = JetspeedResources.getString( "content.provider." + provider + ".description" );
 
         this.setTitle( title );
         this.setDescription( description );
        
         this.setContent( this.parse( url ) );
             
         //now make sure all the above 4 values are define within JetspeedResources
         if ( url == null ||
              stylesheet == null ||
              title == null ||
              description == null ) {
             throw new PortletException( "Not all properties defined in JetspeedResources.  See JetspeedResources.properties notes." );
         }
         
         this.getPortletConfig().setURL( url );
         
         //set the last modification date for this file so that if it is 
         //modified this portlet can be expired from the cache.
         
         try {
             this.lastModified = JetspeedDiskCache.getInstance()
                 .getEntry( this.url ).getLastModified();
         } catch ( IOException e ) {
             logger.error("Exception",  e);
         }
         
     }
     
     /***
     Parse out the JCP URL and return it as a concrete element
     */
     private ConcreteElement parse( String url ) throws PortletException {
  
             
         //now get the url and stylesheet from the JetspeedDiskCache store...
 
         try {
         
         url = JetspeedDiskCache.getInstance()
             .getEntry( url ).getURL();
 
         this.stylesheet = JetspeedDiskCache.getInstance()
             .getEntry( this.stylesheet ).getURL();
         } catch (IOException e) {
             logger.error( "Couldn't transform content.", e );
             throw new PortletException( "Couldn't transform content.  Please see error log" );
         }
 
         
         try {
             
             return new JetspeedClearElement( SimpleTransform.transform( url, stylesheet ) );
             
         } catch (SAXException e) {
             logger.error( "Couldn't transform content.", e );
             throw new PortletException( "Couldn't transform content.  Please see error log" );
         }
 
        
     }
     
 }