package org.apache.turbine.services.security.torque;
   
   /*
    * 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.
   */
  
  import java.beans.PropertyDescriptor;
  
  import java.util.ArrayList;
  import java.util.Iterator;
  import java.util.List;
  
  import org.apache.commons.configuration.Configuration;
  
  import org.apache.commons.logging.Log;
  import org.apache.commons.logging.LogFactory;
  
  import org.apache.torque.TorqueException;
  import org.apache.torque.om.Persistent;
  import org.apache.torque.util.BasePeer;
  import org.apache.torque.util.Criteria;
  
  import org.apache.turbine.om.security.Group;
  import org.apache.turbine.services.InitializationException;
  import org.apache.turbine.services.security.TurbineSecurity;
  import org.apache.turbine.util.security.DataBackendException;
  import org.apache.turbine.util.security.GroupSet;
  
  /***
   * This class capsulates all direct Peer access for the Group entities.
   * It allows the exchange of the default Turbine supplied TurbineGroupPeer
   * class against a custom class.
   *
   * @author <a href="mailto:hps@intermeta.de">Henning P. Schmiedehausen</a>
   * @version $Id: GroupPeerManager.java 534527 2007-05-02 16:10:59Z tv $
   *
   */
  public class GroupPeerManager
      implements GroupPeerManagerConstants
  {
      /*** The class of the Peer the TorqueSecurityService uses */
      private static Class groupPeerClass = null;
  
      /*** The class name of the objects returned by the configured peer. */
      private static Class groupObject = null;
  
      /*** The name of the Table used for Group Object queries  */
      private static String tableName = null;
  
      /*** The name of the column used as "Name" Column */
      private static String nameColumn = null;
  
      /*** The name of the column used as "Id" Column */
      private static String idColumn = null;
  
      /*** The "Name" property descriptor */
      private static PropertyDescriptor namePropDesc = null;
  
      /*** The "Id" property descriptor */
      private static PropertyDescriptor idPropDesc = null;
  
      /*** Logging */
      static Log log = LogFactory.getLog(GroupPeerManager.class);
  
      /***
       * Initializes the GroupPeerManager, loading the class object for the
       * Peer used to retrieve Group objects
       *
       * @param conf The configuration object used to configure the Manager
       *
       * @exception InitializationException A problem occured during initialization
       */
  
      public static void init(Configuration conf)
          throws InitializationException
      {
          String groupPeerClassName = conf.getString(GROUP_PEER_CLASS_KEY,
                                                     GROUP_PEER_CLASS_DEFAULT);
          String groupObjectName = null;
  
          try
          {
              groupPeerClass = Class.forName(groupPeerClassName);
  
             tableName  = (String) groupPeerClass.getField("TABLE_NAME").get(null);
 
             //
             // We have either an user configured Object class or we use the default
             // as supplied by the Peer class
             //
             groupObject = getPersistenceClass(); // Default from Peer, can be overridden
 
             groupObjectName = conf.getString(GROUP_CLASS_KEY,
                     groupObject.getName());
 
             groupObject = Class.forName(groupObjectName); // Maybe the user set a new value...
 
             // If any of the following Field queries fails, the group subsystem
             // is unusable. So check this right here at init time, which saves
             // us much time and hassle if it fails...
             nameColumn = (String) groupPeerClass.getField(conf
                     .getString(GROUP_NAME_COLUMN_KEY, GROUP_NAME_COLUMN_DEFAULT)
                     ).get(null);
 
             idColumn = (String) groupPeerClass.getField(conf
                     .getString(GROUP_ID_COLUMN_KEY, GROUP_ID_COLUMN_DEFAULT)
                     ).get(null);
 
             namePropDesc = new PropertyDescriptor(conf
                     .getString(GROUP_NAME_PROPERTY_KEY,
                     GROUP_NAME_PROPERTY_DEFAULT), groupObject);
 
             idPropDesc = new PropertyDescriptor(conf
                     .getString(GROUP_ID_PROPERTY_KEY,
                     GROUP_ID_PROPERTY_DEFAULT), groupObject);
         }
         catch (Exception e)
         {
             if (groupPeerClassName == null || groupPeerClass == null)
             {
                 throw new InitializationException(
                     "Could not find GroupPeer class ("
                     + groupPeerClassName + ")", e);
             }
             if (tableName == null)
             {
                 throw new InitializationException(
                     "Failed to get the table name from the Peer object", e);
             }
 
             if (groupObject == null || groupObjectName == null)
             {
                 throw new InitializationException(
                     "Failed to get the object type from the Peer object", e);
             }
 
             if (nameColumn == null || namePropDesc == null)
             {
                 throw new InitializationException(
                     "GroupPeer " + groupPeerClassName + " has no name column information!", e);
             }
             if (idColumn == null || idPropDesc == null)
             {
                 throw new InitializationException(
                     "GroupPeer " + groupPeerClassName + " has no id column information!", e);
             }
         }
     }
 
     /***
      * Get the name of this table.
      *
      * @return A String with the name of the table.
      */
     public static String getTableName()
     {
         return tableName;
     }
 
     /***
      * Returns the fully qualified name of the Column to
      * use as the Name Column for a group
      *
      * @return A String containing the column name
      */
     public static String getNameColumn()
     {
         return nameColumn;
     }
 
     /***
      * Returns the fully qualified name of the Column to
      * use as the Id Column for a group
      *
      * @return A String containing the column id
      */
     public static String getIdColumn()
     {
         return idColumn;
     }
 
     /***
      * Returns the full name of a column.
      *
      * @param name The column to fully qualify
      *
      * @return A String with the full name of the column.
      */
     public static String getColumnName(String name)
     {
         StringBuffer sb = new StringBuffer();
         sb.append(getTableName());
         sb.append(".");
         sb.append(name);
         return sb.toString();
     }
 
     /***
      * Returns a new, empty object for the underlying peer.
      * Used to create a new underlying object
      *
      * @return A new object which is compatible to the Peer
      *         and can be used as a Group object
      *
      */
 
     public static Persistent newPersistentInstance()
     {
         Persistent obj = null;
 
         if(groupObject == null)
         {
             // This can happen if the Turbine wants to determine the
             // name of the anonymous user before the security service
             // has been initialized. In this case, the Peer Manager
             // has not yet been inited and the groupObject is still
             // null. Return null in this case.
             //
             return obj;
         }
 
         try
         {
             obj = (Persistent) groupObject.newInstance();
         }
         catch (Exception e)
         {
             log.error("Could not instantiate a group object", e);
             obj = null;
         }
         return obj;
     }
 
     /***
      * Retrieves/assembles a GroupSet of all of the Groups.
      *
      * @return A set of all the Groups in the system
      * @exception Exception A generic exception.
      */
     public static GroupSet retrieveSet()
         throws Exception
     {
         return retrieveSet(new Criteria());
     }
 
     /***
      * Retrieves/assembles a GroupSet based on the Criteria passed in
      *
      * @param criteria A criteria containing a pre-assembled set of criterias
      *                 for the GroupSet
      *
      * @return A Set of groups which fulfil the required criterias
      *
      * @exception Exception A generic exception
      *
      */
     public static GroupSet retrieveSet(Criteria criteria)
         throws Exception
     {
         List results = doSelect(criteria);
         GroupSet gs = new GroupSet();
 
         for(Iterator it = results.iterator(); it.hasNext(); )
         {
             gs.add((Group) it.next());
         }
         return gs;
     }
 
     /***
      * Checks if a Group is defined in the system. The name
      * is used as query criteria.
      *
      * @param group The Group to be checked.
      * @return <code>true</code> if given Group exists in the system.
      * @throws DataBackendException when more than one Group with
      *         the same name exists.
      * @throws Exception A generic exception.
      */
     public static boolean checkExists(Group group)
         throws DataBackendException, Exception
     {
         Criteria criteria = new Criteria();
 
         criteria.addSelectColumn(getIdColumn());
 
         criteria.add(getNameColumn(), group.getName());
 
         List results = BasePeer.doSelect(criteria);
 
         if (results.size() > 1)
         {
             throw new DataBackendException("Multiple groups named '" +
                                            group.getName() + "' exist!");
         }
 
         return (results.size() == 1);
     }
 
     /*
      * ========================================================================
      *
      * WARNING! Do not read on if you have a weak stomach. What follows here
      * are some abominations thanks to the braindead static peers of Torque
      * and the rigidity of Java....
      *
      * ========================================================================
      *
      */
 
     /***
      * Calls buildCriteria(Group group) in the configured GroupPeer. If you get
      * a ClassCastException in this routine, you put a Group object into this
      * method which can't be cast into an object for the TorqueSecurityService. This is a
      * configuration error most of the time.
      *
      * @param group An object which implements the Group interface
      *
      * @return A criteria for the supplied group object
      */
 
     public static Criteria buildCriteria(Group group)
     {
         Criteria crit;
 
         try
         {
             Class[] clazz = new Class[] { groupObject };
             Object[] params =
               new Object[] { ((TorqueGroup) group).getPersistentObj() };
 
             crit =  (Criteria) groupPeerClass
                 .getMethod("buildCriteria", clazz)
                 .invoke(null, params);
         }
         catch (Exception e)
         {
             crit = null;
         }
 
         return crit;
     }
 
     /***
      * Invokes doUpdate(Criteria c) on the configured Peer Object
      *
      * @param criteria  A Criteria Object
      *
      * @exception TorqueException A problem occured.
      */
 
     public static void doUpdate(Criteria criteria)
         throws TorqueException
     {
         try
         {
             Class[] clazz = new Class[] { Criteria.class };
             Object[] params = new Object[] { criteria };
 
             groupPeerClass
                 .getMethod("doUpdate", clazz)
                 .invoke(null, params);
         }
         catch (Exception e)
         {
             throw new TorqueException("doUpdate failed", e);
         }
     }
 
     /***
      * Invokes doInsert(Criteria c) on the configured Peer Object
      *
      * @param criteria  A Criteria Object
      *
      * @exception TorqueException A problem occured.
      */
 
     public static void doInsert(Criteria criteria)
         throws TorqueException
     {
         try
         {
             Class[] clazz = new Class[] { Criteria.class };
             Object[] params = new Object[] { criteria };
 
             groupPeerClass
                 .getMethod("doInsert", clazz)
                 .invoke(null, params);
         }
         catch (Exception e)
         {
             throw new TorqueException("doInsert failed", e);
         }
     }
 
     /***
      * Invokes doSelect(Criteria c) on the configured Peer Object
      *
      * @param criteria  A Criteria Object
      *
      * @return A List of Group Objects selected by the Criteria
      *
      * @exception TorqueException A problem occured.
      */
     public static List doSelect(Criteria criteria)
         throws TorqueException
     {
         List list;
 
         try
         {
             Class[] clazz = new Class[] { Criteria.class };
             Object[] params = new Object[] { criteria };
 
             list = (List) groupPeerClass
                 .getMethod("doSelect", clazz)
                 .invoke(null, params);
         }
         catch (Exception e)
         {
             throw new TorqueException("doSelect failed", e);
         }
         List newList = new ArrayList(list.size());
 
         //
         // Wrap the returned Objects into the configured Peer Objects.
         //
         for (Iterator it = list.iterator(); it.hasNext(); )
         {
             Group dr = getNewGroup((Persistent) it.next());
             newList.add(dr);
         }
 
         return newList;
     }
 
     /***
      * Invokes doDelete(Criteria c) on the configured Peer Object
      *
      * @param criteria  A Criteria Object
      *
      * @exception TorqueException A problem occured.
      */
     public static void doDelete(Criteria criteria)
         throws TorqueException
     {
         try
         {
             Class[] clazz =
               new Class[] { Criteria.class };
             Object[] params = new Object[] { criteria };
 
             groupPeerClass
                 .getMethod("doDelete", clazz)
                 .invoke(null, params);
         }
         catch (Exception e)
         {
             throw new TorqueException("doDelete failed", e);
         }
     }
 
     /***
      * Invokes setName(String s) on the supplied base object
      *
      * @param obj The object to use for setting the name
      *
      * @param name The Name to set
      */
     public static void setGroupName(Persistent obj, String name)
     {
         if(obj == null)
         {
             return;
         }
 
         try
         {
             Object[] params = new Object[] { name };
             namePropDesc.getWriteMethod().invoke(obj, params);
         }
         catch (ClassCastException cce)
         {
             String msg = obj.getClass().getName() + " does not seem to be a Group Object!";
             log.error(msg);
             throw new RuntimeException(msg);
         }
         catch (Exception e)
         {
             log.error(e, e);
         }
     }
 
     /***
      * Invokes getName() on the supplied base object
      *
      * @param obj The object to use for getting the name
      *
      * @return A string containing the name
      */
     public static String getGroupName(Persistent obj)
     {
         String name = null;
 
         if(obj == null)
         {
             return null;
         }
 
         try
         {
             name = (String) namePropDesc
                 .getReadMethod()
                 .invoke(obj, new Object[] {});
         }
         catch (ClassCastException cce)
         {
             String msg = obj.getClass().getName() + " does not seem to be a Group Object!";
             log.error(msg);
             throw new RuntimeException(msg);
         }
         catch (Exception e)
         {
             log.error(e, e);
         }
         return name;
     }
 
     /***
      * Invokes setId(int n) on the supplied base object
      *
      * @param obj The object to use for setting the name
      * @param id The new Id
      */
     public static void setId(Persistent obj, int id)
     {
         if(obj == null)
         {
             return;
         }
 
         try
         {
             Object[] params = new Object[] { Integer.TYPE };
             idPropDesc.getWriteMethod().invoke(obj, params);
         }
         catch (ClassCastException cce)
         {
             String msg = obj.getClass().getName() + " does not seem to be a Group Object!";
             log.error(msg);
             throw new RuntimeException(msg);
         }
         catch (Exception e)
         {
             log.error(e, e);
         }
     }
 
     /***
      * Invokes getId() on the supplied base object
      *
      * @param obj The object to use for getting the id
      *
      * @return The Id of this object
      */
     public static Integer getIdAsObj(Persistent obj)
     {
         Integer id = null;
 
         if(obj == null)
         {
             return new Integer(0);
         }
 
         try
         {
             id = (Integer) idPropDesc
                 .getReadMethod()
                 .invoke(obj, new Object[] {});
         }
         catch (ClassCastException cce)
         {
             String msg = obj.getClass().getName() + " does not seem to be a Group Object!";
             log.error(msg);
             throw new RuntimeException(msg);
         }
         catch (Exception e)
         {
             log.error(e, e);
         }
         return id;
     }
 
     /***
      * Returns the Class of the configured Object class
      * from the peer
      *
      * @return The class of the objects returned by the configured peer
      *
      */
 
     private static Class getPersistenceClass()
     {
         Class persistenceClass = null;
 
         try
         {
             Object[] params = new Object[0];
 
             persistenceClass =  (Class) groupPeerClass
                 .getMethod("getOMClass", (Class[])null)
                 .invoke(null, params);
         }
         catch (Exception e)
         {
             persistenceClass = null;
         }
 
         return persistenceClass;
     }
 
     /***
      * Returns a new, configured Group Object with
      * a supplied Persistent object at its core
      *
      * @param p The persistent object
      *
      * @return a new, configured Group Object
      *
      * @exception Exception Could not create a new Object
      *
      */
 
     public static Group getNewGroup(Persistent p)
     {
         Group g = null;
         try
         {
             Class groupWrapperClass = TurbineSecurity.getGroupClass();
 
             Class [] clazz = new Class [] { Persistent.class };
             Object [] params = new Object [] { p };
 
             g = (Group) groupWrapperClass
                 .getConstructor(clazz)
                 .newInstance(params);
         }
         catch (Exception e)
         {
             log.error("Could not instantiate a new group from supplied persistent: ", e);
         }
 
         return g;
     }
 }