/*
    *  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.directory.api.util;
  
  
  import java.util.Collections;
  import java.util.LinkedList;
  import java.util.List;
  
  import org.apache.directory.api.i18n.I18n;
  
  
  /**
   * A monitor that tracks both, mandatory and optional components.
   *
   * @author <a href="mailto:dev@directory.apache.org">Apache Directory Project</a>
   */
  public class MandatoryAndOptionalComponentsMonitor implements ComponentsMonitor
  {
  
      /** The mandatory components monitor. */
      private ComponentsMonitor mandatoryComponentsMonitor;
  
      /** The optional components monitor. */
      private ComponentsMonitor optionalComponentsMonitor;
  
  
      /**
       * Instantiates a new mandatory and optional components monitor. The mandatory and optional
       * components must be disjunct.
       *
       * @param mandatoryComponents the mandatory components
       * @param optionalComponents the optional components
       * @throws IllegalArgumentException if the same component is defined as mandatory and optional
       */
      public MandatoryAndOptionalComponentsMonitor( String[] mandatoryComponents, String[] optionalComponents )
      {
          // check for common elements
          for ( int i = 0; i < mandatoryComponents.length; i++ )
          {
              for ( int j = 0; j < optionalComponents.length; j++ )
              {
                  if ( mandatoryComponents[i].equals( optionalComponents[j] ) )
                  {
                      throw new IllegalArgumentException( I18n.err( I18n.ERR_04415, mandatoryComponents[i] ) );
                  }
              }
          }
  
          mandatoryComponentsMonitor = new MandatoryComponentsMonitor( mandatoryComponents );
          optionalComponentsMonitor = new OptionalComponentsMonitor( optionalComponents );
      }
  
  
      /**
       * {@inheritDoc}
       */
      public ComponentsMonitor useComponent( String component )
      {
          try
          {
              mandatoryComponentsMonitor.useComponent( component );
          }
          catch ( IllegalArgumentException e1 )
          {
              try
              {
                  optionalComponentsMonitor.useComponent( component );
              }
              catch ( IllegalArgumentException e2 )
              {
                  throw new IllegalArgumentException( I18n.err( I18n.ERR_04416, component ), e1 );
              }
          }
  
          return this;
      }
  
  
      /**
       * {@inheritDoc}
      */
     public boolean allComponentsUsed()
     {
         return ( mandatoryComponentsMonitor.allComponentsUsed() && optionalComponentsMonitor.allComponentsUsed() );
     }
 
 
     /**
      * {@inheritDoc}
      */
     public boolean finalStateValid()
     {
         return ( mandatoryComponentsMonitor.finalStateValid() && optionalComponentsMonitor.finalStateValid() );
     }
 
 
     /**
      * {@inheritDoc}
      */
     public List<String> getRemainingComponents()
     {
         List<String> remainingComponents = new LinkedList<String>();
 
         remainingComponents.addAll( mandatoryComponentsMonitor.getRemainingComponents() );
         remainingComponents.addAll( optionalComponentsMonitor.getRemainingComponents() );
 
         return Collections.unmodifiableList( remainingComponents );
     }
 
 }