/*
    * 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.om.page.impl;
  
  import java.util.HashMap;
  import java.util.Iterator;
  import java.util.List;
  import java.util.Map;
  
  import org.apache.jetspeed.om.common.SecurityConstraint;
  import org.apache.jetspeed.om.page.PageSecurity;
  import org.apache.jetspeed.om.page.SecurityConstraintsDef;
  import org.apache.jetspeed.page.document.impl.DocumentImpl;
  import org.apache.jetspeed.page.impl.DatabasePageManagerUtils;
  
  /***
   * PageSecurityImpl
   *
   * @author <a href="mailto:rwatler@apache.org">Randy Watler</a>
   * @version $Id$
   */
  public class PageSecurityImpl extends DocumentImpl implements PageSecurity
  {
      private List constraintsDefs;
      private List globalConstraintsRefs;
  
      private PageSecurityConstraintsDefList securityConstraintsDefs;
      private Map securityConstraintsDefsMap;
      private PageSecurityConstraintsRefList globalSecurityConstraintsRefs;
  
      public PageSecurityImpl()
      {
          super(null);
      }
  
      /***
       * accessConstraintsDefs
       *
       * Access mutable persistent collection member for List wrappers.
       *
       * @return persistent collection
       */
      List accessConstraintsDefs()
      {
          // create initial collection if necessary
          if (constraintsDefs == null)
          {
              constraintsDefs = DatabasePageManagerUtils.createList();
          }
          return constraintsDefs;
      }
  
      /***
       * accessGlobalConstraintsRefs
       *
       * Access mutable persistent collection member for List wrappers.
       *
       * @return persistent collection
       */
      List accessGlobalConstraintsRefs()
      {
          // create initial collection if necessary
          if (globalConstraintsRefs == null)
          {
              globalConstraintsRefs = DatabasePageManagerUtils.createList();
          }
          return globalConstraintsRefs;
      }
  
      /***
       * clearSecurityConstraintsDefsMap
       *
       * Clear previously cached security constraints definitions map.
       */
      synchronized void clearSecurityConstraintsDefsMap()
      {
          securityConstraintsDefsMap = null;
      }
  
      /* (non-Javadoc)
       * @see org.apache.jetspeed.om.common.SecuredResource#newSecurityConstraint()
       */
      public SecurityConstraint newSecurityConstraint()
      {
          // return specific security constraint definition instance
         return new PageSecuritySecurityConstraintImpl();
     }
 
     /* (non-Javadoc)
      * @see org.apache.jetspeed.om.page.PageSecurity#getSecurityConstraintsDefs()
      */
     public List getSecurityConstraintsDefs()
     {
         // return mutable constraints defs list
         // by using list wrapper to manage
         // element uniqueness
         if (securityConstraintsDefs == null)
         {
             securityConstraintsDefs = new PageSecurityConstraintsDefList(this);
         }
         return securityConstraintsDefs;
     }
     
     /* (non-Javadoc)
      * @see org.apache.jetspeed.om.common.SecuredResource#newSecurityConstraintsDef()
      */
     public SecurityConstraintsDef newSecurityConstraintsDef()
     {
         // return specific security constraints definition instance
         return new SecurityConstraintsDefImpl();
     }
 
     /* (non-Javadoc)
      * @see org.apache.jetspeed.om.page.PageSecurity#setSecurityConstraintsDefs(java.util.List)
      */
     public void setSecurityConstraintsDefs(List definitions)
     {
         // set constraints defs by replacing existing
         // entries with new elements if new collection
         // is specified
         List securityConstraintsDefs = getSecurityConstraintsDefs();
         if (definitions != securityConstraintsDefs)
         {
             // replace all constraints definitions
             securityConstraintsDefs.clear();
             if (definitions != null)
             {
                 securityConstraintsDefs.addAll(definitions);
             }
         }
         // clear cached security constraints definition map
         clearSecurityConstraintsDefsMap();
     }
 
     /* (non-Javadoc)
      * @see org.apache.jetspeed.om.page.PageSecurity#getSecurityConstraintsDef(java.lang.String)
      */
     public synchronized SecurityConstraintsDef getSecurityConstraintsDef(String name)
     {
         // build and cache security constraints definitions
         // map if necessary upon realization or after modification
         if ((getSecurityConstraintsDefs() != null) && (securityConstraintsDefsMap == null))
         {
             securityConstraintsDefsMap = new HashMap((getSecurityConstraintsDefs().size() * 2) + 1);
             Iterator definitionsIter = getSecurityConstraintsDefs().iterator();
             while (definitionsIter.hasNext())
             {
                 SecurityConstraintsDef definition = (SecurityConstraintsDef)definitionsIter.next();
                 String definitionName = definition.getName();
                 if (!securityConstraintsDefsMap.containsKey(definitionName))
                 {
                     securityConstraintsDefsMap.put(definitionName, definition);
                 }
             }
         }
         // lookup constraints definition using cached map 
         if (securityConstraintsDefsMap != null)
         {
             return (SecurityConstraintsDef)securityConstraintsDefsMap.get(name);
         }
         return null;
     }
 
     /* (non-Javadoc)
      * @see org.apache.jetspeed.om.page.PageSecurity#getGlobalSecurityConstraintsRefs()
      */
     public List getGlobalSecurityConstraintsRefs()
     {
         // return mutable constraints refs list
         // by using list wrapper to manage apply
         // order and element uniqueness
         if (globalSecurityConstraintsRefs == null)
         {
             globalSecurityConstraintsRefs = new PageSecurityConstraintsRefList(this);
         }
         return globalSecurityConstraintsRefs;
     }
     
     /* (non-Javadoc)
      * @see org.apache.jetspeed.om.page.PageSecurity#setGlobalSecurityConstraintsRefs(java.util.List)
      */
     public void setGlobalSecurityConstraintsRefs(List constraintsRefs)
     {
         // set constraints refs using ordered ref
         // names by replacing existing entries with
         // new elements if new collection is specified
         List globalSecurityConstraintsRefs = getGlobalSecurityConstraintsRefs();
         if (constraintsRefs != globalSecurityConstraintsRefs)
         {
             // replace all constraints ref names
             globalSecurityConstraintsRefs.clear();
             if (constraintsRefs != null)
             {
                 globalSecurityConstraintsRefs.addAll(constraintsRefs);
             }
         }
     }
 
     /* (non-Javadoc)
      * @see org.apache.jetspeed.page.document.Node#getType()
      */
     public String getType()
     {
         return DOCUMENT_TYPE;
     }
 }