SiteEventListener.java

/**********************************************************************************
* $URL:https://source.sakaiproject.org/svn/osp/trunk/common/api-impl/src/java/org/theospi/portfolio/worksite/mgt/impl/SiteEventListener.java $
* $Id:SiteEventListener.java 9134 2006-05-08 20:28:42Z chmaurer@iupui.edu $
***********************************************************************************
*
 * Copyright (c) 2005, 2006, 2008 The Sakai 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.osedu.org/licenses/ECL-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.theospi.portfolio.worksite.mgt.impl;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.sakaiproject.component.api.ComponentManager;
import org.sakaiproject.entity.api.EntityManager;
import org.sakaiproject.entity.api.Reference;
import org.sakaiproject.event.api.Event;
import org.sakaiproject.event.cover.EventTrackingService;
import org.sakaiproject.exception.IdUnusedException;
import org.sakaiproject.site.api.Site;
import org.sakaiproject.site.api.SitePage;
import org.sakaiproject.site.api.ToolConfiguration;
import org.sakaiproject.site.cover.SiteService;
import org.sakaiproject.tool.api.Tool;
import org.sakaiproject.tool.cover.ToolManager;
import org.springframework.orm.hibernate3.support.HibernateDaoSupport;
import org.theospi.portfolio.shared.model.OspException;
import org.theospi.portfolio.worksite.intf.ToolEventListener;
import org.theospi.portfolio.worksite.model.SiteTool;

import java.util.*;

public class SiteEventListener extends HibernateDaoSupport implements Observer {
   protected final transient Log logger = LogFactory.getLog(getClass());

   public final static String LISTENER_PROPERTY_TAG = "theospi.toolListenerId";
   private ComponentManager componentManager;
   private EntityManager entityManager;
   
   private List siteHelperTools = new ArrayList();

   /**
    * This method is called whenever the observed object is changed. An
    * application calls an <tt>Observable</tt> object's
    * <code>notifyObservers</code> method to have all the object's
    * observers notified of the change.
    *
    * @param o   the observable object.
    * @param arg an argument passed to the <code>notifyObservers</code>
    *            method.
    */
   public void update(Observable o, Object arg) {
      if (arg instanceof Event) {
         processEvent((Event)arg, o);
      }
   }

   protected void processEvent(Event event, Observable arg) {
      if (event.getEvent().equals(SiteService.SECURE_ADD_SITE) ||
         event.getEvent().equals(SiteService.SECURE_UPDATE_SITE)) {
         // check out the update
         try {
            Reference ref = getEntityManager().newReference(event.getResource());
            Site site = SiteService.getSite(ref.getId());
            processSite(site);

            if (event.getEvent().equals(SiteService.SECURE_UPDATE_SITE)) {
               processUpdate(site);
            }
         } catch (IdUnusedException e) {
            logger.error("error getting site object", e);
            throw new OspException(e);
         }
      }
      else if (event.getEvent().equals(SiteService.SECURE_REMOVE_SITE)) {
         removeAll(getEntityManager().newReference(event.getResource()));
      }
   }

   protected void processUpdate(Site site) {
      Collection siteTools = getSiteTools(site.getId());

      for (Iterator i=siteTools.iterator();i.hasNext();) {
         SiteTool tool = (SiteTool)i.next();

         ToolConfiguration toolConfig = SiteService.findTool(tool.getToolId());

         if (toolConfig == null) {
            removeTool(tool);
         }
      }
   }

   protected void removeTool(SiteTool tool) {
      ToolEventListener listener = (ToolEventListener) getComponentManager().get(tool.getListenerId());

      listener.toolRemoved(tool);

      getHibernateTemplate().delete(tool);

   }

   protected void removeAll(Reference reference) {
      Collection siteTools = getSiteTools(reference.getId());

      for (Iterator i=siteTools.iterator();i.hasNext();) {
         SiteTool tool = (SiteTool)i.next();
         removeTool(tool);
      }
   }

   protected void processSite(Site site) {
      List pages = site.getPages();
      
      for (Iterator i=getSiteHelperTools().iterator(); i.hasNext();) {
         String toolId = (String)i.next();
         Tool toolPlacement = ToolManager.getTool(toolId);
         if (toolPlacement != null) {
            String listenerId = 
               toolPlacement.getRegisteredConfig().getProperty(LISTENER_PROPERTY_TAG);
            if (listenerId != null) {
               ToolEventListener listener = (ToolEventListener) getComponentManager().get(listenerId);
   
               if (listener != null) {
                  listener.helperSiteChanged(site);
               }
            }
         }
      }  
      
      for (Iterator i=pages.iterator();i.hasNext();) {
         processPage((SitePage)i.next());
      }
   }
   
   protected void processPage(SitePage sitePage) {
      List tools = sitePage.getTools();

      for (Iterator i=tools.iterator();i.hasNext();) {
         processTool((ToolConfiguration)i.next());
      }
   }

   protected void processTool(ToolConfiguration toolConfiguration) {
      String listenerId =
            toolConfiguration.getConfig().getProperty(LISTENER_PROPERTY_TAG);
      if (listenerId != null) {
         storeTool(toolConfiguration);
         ToolEventListener listener = (ToolEventListener) getComponentManager().get(listenerId);

         if (listener != null) {
            listener.toolSiteChanged(toolConfiguration);
         }
      }
   }

   public void init() {
      EventTrackingService.addObserver(this);
   }

   protected void storeTool(ToolConfiguration toolConfiguration) {
      SiteTool tool = new SiteTool();
      tool.setSiteId(toolConfiguration.getContainingPage().getContainingSite().getId());
      tool.setToolId(toolConfiguration.getId());

      if (getSiteTool(tool.getSiteId(), tool.getToolId()).size() > 0) {
         return;
      }

      tool.setListenerId(toolConfiguration.getConfig().getProperty(LISTENER_PROPERTY_TAG));

      getHibernateTemplate().saveOrUpdate(tool);
   }

   protected Collection getSiteTool(String siteId, String toolId) {
      return getHibernateTemplate().findByNamedQuery("bySiteAndTool",
         new Object[]{siteId, toolId});
   }

   protected Collection getSiteTools(String siteId) {
      return getHibernateTemplate().findByNamedQuery("bySite", siteId);
   }

   public ComponentManager getComponentManager() {
      return org.sakaiproject.component.cover.ComponentManager.getInstance();
   }

   public EntityManager getEntityManager() {
      return entityManager;
   }

   public void setEntityManager(EntityManager entityManager) {
      this.entityManager = entityManager;
   }

   public List getSiteHelperTools() {
      return siteHelperTools;
   }

   public void setSiteHelperTools(List siteHelperTools) {
      this.siteHelperTools = siteHelperTools;
   }
}