/*
    * Copyright 2000-2001,2004 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;
  
  // Java imports
  import java.util.ArrayList;
  import java.util.Iterator;
  
  
  // ECS imports
  import org.apache.ecs.ConcreteElement;
  
  // Jetspeed imports
  import org.apache.jetspeed.om.profile.Entry;
  import org.apache.jetspeed.om.profile.MetaInfo;
  import org.apache.jetspeed.om.profile.PSMLDocument;
  import org.apache.jetspeed.om.profile.Parameter;
  import org.apache.jetspeed.om.profile.Profile;
  import org.apache.jetspeed.om.profile.psml.PsmlParameter;
  import org.apache.jetspeed.portal.Portlet;
  import org.apache.jetspeed.services.logging.JetspeedLogFactoryService;
  import org.apache.jetspeed.services.logging.JetspeedLogger;
  import org.apache.jetspeed.services.rundata.JetspeedRunData;
  
  //Turbine imports
  import org.apache.turbine.util.RunData;
  
  /***
   * Default Implementation of Jetspeed Portlet Instance.
   * It implements the methods for getting, setting and removing attributes from 
   * portlet instance persistence storage.
   *
   * In a Jetspeed 1.4x PSML profile, the default XML format for an instance and attribute is:
   *
   * <entry>
   *    <parameter name="someName" value="someValue"/>
   *
   * Since this modifies PSMLDocuments, it will make a clone once modification starts.
   *
   * @author <a href="mailto:sweaver@rippe.com">Scott Weaver</a>
   * @author <a href="mailto:ggolden@apache.org">Glenn R. Golden</a>
   * @version $Id: JetspeedPortletInstance.java,v 1.9 2004/02/23 04:05:35 jford Exp $
   */
  public class JetspeedPortletInstance implements PortletInstance
  {
      /***
       * Static initialization of the logger for this class
       */    
      private static final JetspeedLogger logger = JetspeedLogFactoryService.getLogger(JetspeedPortletInstance.class.getName());    
      
      /*** The Profile (and PSMLDocument) that we started with, considered RO */
      private Profile m_profile = null;
  
      /*** The Profile (and PSMLDocument) that we cloned to edit. */
      private Profile m_clonedProfile = null;
  
      /*** The rundata - WARNING: it is VERY DANGEROUS to store rundata like this.
          Rundata objects are re-used, and are only good within one request.
          This means that a PortletInstance CANNOTA BE STORED BEYOND A SINGLE REQUEST! */
      private JetspeedRunData m_rundata = null;
  
      /*** 
       * keeping an instance of the actual Portlet around helps us with
       * getting information that is not directly available from the PSML profile
       */
      private Portlet m_portlet = null;
      
      /***
       * Constructs a PortletInstance from a Portlet and a RunData.
       *
       * @param Portlet The parent portlet of this instance.
       * @param RunData Jetspeed Run Data
       */
      public JetspeedPortletInstance(Portlet portlet, RunData data)
      {
          this(portlet, ((JetspeedRunData) data).getProfile());
          m_rundata = (JetspeedRunData)data;
          
          // if we are in an edit already, use that as the clone
          m_clonedProfile = ((JetspeedRunData)data).getCustomizedProfile();
      }
  
     /***
      * Constructs a PortletInstance from a Portlet and a Profile
      *
      * @param Portlet The parent portlet of this instance.
     * @param Profile The profile containing the instance.
     */
     public JetspeedPortletInstance(Portlet portlet, Profile profile)
     {
         m_portlet = portlet;
         m_profile = profile;
     }    
  
      /***
      * Protect the constructor so it can only be instantitated by
      * by the PortalPersistenceService
      */
     protected JetspeedPortletInstance()
     {
         // does nothin'
     }
 
     /***
      * @see PortletInstance#getAttribute()
      */
     public String getAttribute(String name, String dftValue)
     {
         Entry entry = getEntry();
 
         if (entry == null)
         {
             return dftValue;
         }
         Parameter attr = entry.getParameter(name);
         if (attr != null)
         {
             return attr.getValue();
         }
         else
         {
             return dftValue;
         }
     }
 
     /***
      * @see PortletInstance#getAttribute()
      */
     public String getAttribute(String name)
     {
         Entry entry = getEntry();
 
         if (entry == null)
         {
             return "";
         }
         Parameter attr = entry.getParameter(name);
         if (attr != null)
         {
             return attr.getValue();
         }
         else
         {
             return "";
         }
     }
 
     /***
      * @see PortletInstance#setAttribute(String, String)
      */
     public void setAttribute(String name, String value)
     {
         // make sure we are updating and using the clone now
         setupForUpdate();
         
         Entry entry = getEntry();
 
         Parameter attr = entry.getParameter(name);
          
          // Setting a attribute to null should just remove it.
         if(value == null)
         {
             removeAttribute(name);
         }
         else if (attr != null)
         {
             attr.setValue(value);
         }
         // If an attribute does not exist, then add it.
         else
         {
             PsmlParameter newAttr = new PsmlParameter();
             newAttr.setName(name);
             newAttr.setValue(value);
             entry.addParameter(newAttr);
         }
     }
 
     /***
      * @see PortletInstance#removeAttribute(String)
      */
     public void removeAttribute(String name)
     {
         // make sure we are updating and using the clone now
         setupForUpdate();
         
         Entry entry = getEntry();
 
         // I am assuming that we only allow one parameter per name
         Iterator params = entry.getParameterIterator();
         int index = -1;
         int count = 0;
         while (params.hasNext())
         {
             Parameter param = (Parameter) params.next();
             if (param.getName().equalsIgnoreCase(name))
             {
                 index = count;
                 break;
             }
             count++;
         }
 
         // We have to wait until we are outside the loop to remove
         // or else we throw a ConcurrentModificationException		
         if (index != -1)
         {
             entry.removeParameter(index);           
         }
     }
 
     /***
      * @see PortletInstance#removeAllAttributes()
      */
     public void removeAllAttributes()
     {
         // make sure we are updating and using the clone now
         setupForUpdate();
         
         Entry entry = getEntry();
 
         entry.removeAllParameter();
     }
 
     /***
      * @see PortletInstance#getAttributes()
      */
     public Iterator getAttributes()
     {
         Entry entry = getEntry();
 
         return entry.getParameterIterator();
     }
 
     /***
      * @see PortletInstance#getAttributeNames()
      */
     public Iterator getAttributeNames()
     {
         Iterator itr = getAttributes();
         ArrayList list = new ArrayList();
         while(itr.hasNext());
         {
             Parameter param = (Parameter) itr.next();
             list.add(param.getName());
         }
         
         return list.iterator();
     }
 
     /***
      * @see PortletInstance#getDocument()
      */
     public PSMLDocument getDocument()
     {
         return getProfile().getDocument();
     }
 
     /***
      * @see PortletInstance#getProfile()
      */
     public Profile getProfile()
     {
         // use the clone if we have made it
         if (m_clonedProfile != null) return m_clonedProfile;
 
         return m_profile;
     }
 
     /***
      * @see PortletInstance#getPortlet()
      */
     public Entry getEntry()
     {
         return getDocument().getEntryById(m_portlet.getID());
     }
 
     /***
      * @see PortletInstance#getDescription()
      */
     public String getDescription()
     {
         Entry entry = getEntry();
 
         String description = null;
         if (entry != null)
         {
             MetaInfo metaInfo = entry.getMetaInfo();
             if (metaInfo != null)
             {
                 description = metaInfo.getDescription();
             }
         }
         return m_portlet.getDescription(description);
     }
 
     /***
      * @see PortletInstance#getName()
      */
     public String getName()
     {
         return getEntry().getParent();
     }
 
     /***
      * @see PortletInstance#getTitle()
      */
     public String getTitle()
     {
         Entry entry = getEntry();
 
         String title = null;
         if (entry != null)
         {
             MetaInfo metaInfo = entry.getMetaInfo();
             if (metaInfo != null)
             {
                 title = metaInfo.getTitle();
             }
         }
         return m_portlet.getTitle(title);
     }
 
     /***
      * @see PortletInstance#getImage()
      */
     public String getImage()
     {
         Entry entry = getEntry();
 
         String image = null;
         if (entry != null)
         {
             MetaInfo metaInfo = entry.getMetaInfo();
             if (metaInfo != null)
             {
                 return image = metaInfo.getImage();
             }
         }
         return m_portlet.getImage(image);
     }
 
     /***
      * @see PortletInstance#getPortlet()
      */
     public Portlet getPortlet()
     {
         return m_portlet;
     }
     
     /***
      * @see PortletInstance#getContent()
      */
     public ConcreteElement getContent()
     {
       return m_portlet.getContent(m_rundata);
     }
     
     /***
      * @see PortletInstance#isShowTitleBar()
      */
     public boolean isShowTitleBar()
     {
       return m_portlet.isShowTitleBar(m_rundata);
     }
 
     /***
     * Setup for making a change to the Entry
     * We must not change the PSMLDocument that we started with, instead we make a clone
     * and start using it.
     */
     private void setupForUpdate()
     {
         if (m_clonedProfile != null) return;
         
         try
         {
             m_clonedProfile = (Profile) m_profile.clone();
         }
         catch (CloneNotSupportedException e)
         {
             logger.warn("JetspeedPortletInstance: cannot clone Profile!: " + e);
         }
     }
 }