/*
    * Licensed to the Apache Software Foundation (ASF) under one or more
    * contributor license agreements.  See the NOTICE file distributed with
    * this work for additional information regarding copyright ownership.
    * The ASF licenses this file to You 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.portalsite.impl;
  
  import java.util.Locale;
  
  import org.apache.jetspeed.om.common.GenericMetadata;
  import org.apache.jetspeed.page.document.Node;
  import org.apache.jetspeed.portalsite.Menu;
  import org.apache.jetspeed.portalsite.MenuElement;
  
  /***
   * This abstract class implements common features of portal-site
   * menu elements constructed and returned to decorators.
   * 
   * @author <a href="mailto:rwatler@apache.org">Randy Watler</a>
   * @version $Id: MenuElementImpl.java 516448 2007-03-09 16:25:47Z ate $
   */
  public abstract class MenuElementImpl implements MenuElement, Cloneable
  {
      /***
       * parentMenu - parent menu implementation
       */
      private MenuImpl parent;
  
      /***
       * node - underlying node proxy associated with this
       *        menu element in the site view
       */
      private Node node;
  
      /***
       * skin - inherited skin name for menu element
       */
      private String skin;
  
      /***
       * skinInherited - flag indicating whether skin value
       *                 has been inherited by propagating
       *                 from parent menu
       */
      private boolean skinInherited;
  
      /***
       * MenuElementImpl - constructor
       *
       * @param parent containing menu implementation
       */
      protected MenuElementImpl(MenuImpl parent)
      {
          this.parent = parent;
      }
  
      /***
       * MenuElementImpl - node proxy constructor
       *
       * @param parent containing menu implementation
       * @param node menu element node proxy
       */
      protected MenuElementImpl(MenuImpl parent, Node node)
      {
          this(parent);
          this.node = node;
      }
  
      /***
       * clone - clone this instance
       *
       * @return unparented copy
       */
      public Object clone() throws CloneNotSupportedException
      {
          // clone this object
          MenuElementImpl copy = (MenuElementImpl) super.clone();
  
          // clear parent reference
          copy.parent = null;
          return copy;
      }
  
      /***
       * equals - compare menu element implementations
       *
       * @return equals result
       */
     public boolean equals(Object obj)
     {
         // compare menu implementation by type, url, and
         // name, instances with no url and no name are
         // always considered unique
         if (this.getClass().equals(obj.getClass()))
         {
             String url = getUrl();
             String name = getName();
             if ((url != null) || (name != null))
             {
                 String objUrl = ((MenuElementImpl)obj).getUrl();
                 String objName = ((MenuElementImpl)obj).getName();
                 return ((((name == null) && (objName == null)) || ((name != null) && name.equals(objName))) &&
                         (((url != null) && url.equals(objUrl)) || ((url == null) && (objUrl == null))));
             }
         }
         return false;
     }
 
     /***
      * getElementType - get type of menu element
      *
      * @return MENU_ELEMENT_TYPE, OPTION_ELEMENT_TYPE, or
      *         SEPARATOR_ELEMENT_TYPE
      */
     public abstract String getElementType();
 
     /***
      * getParentMenu - get menu that contains menu element 
      *
      * @return parent menu
      */    
     public Menu getParentMenu()
     {
         return parent;
     }
 
     /***
      * setParentMenu - set menu that contains menu element 
      *
      * @param parentMenu parent menu
      */    
     protected void setParentMenu(Menu parentMenu)
     {
         parent = (MenuImpl)parentMenu;
     }
 
     /***
      * getName - get name of menu element used for default title
      *
      * @return menu element name
      */
     public String getName()
     {
         // no name by default
         return null;
     }
 
     /***
      * getUrl - get url of menu element used for comparison
      *
      * @return folder, page, or link url
      */
     public String getUrl()
     {
         // no url by default
         return null;
     }
 
     /***
      * getTitle - get default title for menu element
      *
      * @return title text
      */
     public String getTitle()
     {
         // return node or default title
         if (node != null)
         {
             return node.getTitle();
         }
         return getName();
     }
 
     /***
      * getShortTitle - get default short title for menu element
      *
      * @return short title text
      */
     public String getShortTitle()
     {
         // return node or default short title
         if (node != null)
         {
             return node.getShortTitle();
         }
         return getName();
     }
 
     /***
      * getTitle - get locale specific title for menu element
      *            from metadata
      *
      * @param locale preferred locale
      * @return title text
      */
     public String getTitle(Locale locale)
     {
         // return node or default title for preferred locale
         if (node != null)
         {
             return node.getTitle(locale);
         }
         return getName();
     }
 
     /***
      * getShortTitle - get locale specific short title for menu
      *                 element from metadata
      *
      * @param locale preferred locale
      * @return short title text
      */
     public String getShortTitle(Locale locale)
     {
         // return node or default short title for preferred locale
         if (node != null)
         {
             return node.getShortTitle(locale);
         }
         return getName();
     }
 
     /***
      * getMetadata - get generic metadata for menu element
      *
      * @return metadata
      */    
     public GenericMetadata getMetadata()
     {
         // return node metadata
         if (node != null)
         {
             GenericMetadata metadata = node.getMetadata();
             if (metadata != null && metadata.getFields() != null && !metadata.getFields().isEmpty())
             {
                 return metadata;
             }
         }
         return null;
     }
 
     /***
      * getSkin - get skin name for menu element
      *
      * @return skin name
      */
     public String getSkin()
     {
         // no skin by default, check parent for
         // skin value and cache locally
         if (!skinInherited)
         {
             if (parent != null)
             {
                 skin = parent.getSkin();
             }
             skinInherited = true;
         }
         return skin;
     }
 
     /***
      * getNode - get menu element node proxy in the site view
      *
      * @return node proxy
      */
     protected Node getNode()
     {
         return node;
     } 
 
     /***
      * setNode - set menu element node proxy in the site view
      *
      * @param node node proxy
      */
     protected void setNode(Node node)
     {
         this.node = node;
     } 
 }