package org.opentrafficsim.core.perception.collections;
   
   import java.util.Collections;
   import java.util.NavigableMap;
   import java.util.NavigableSet;
   
   import org.opentrafficsim.core.perception.HistoryManager;
   
   /**
   * NavigableMap-valued historical state. The current navigable map is always maintained, and past states of the navigable map
   * are obtained by applying the events between now and the requested time in reverse.<br>
   * <br>
   * The set views and sub-maps returned by this class are unmodifiable.
   * <p>
   * Copyright (c) 2013-2019 Delft University of Technology, PO Box 5, 2600 AA, Delft, the Netherlands. All rights reserved. <br>
   * BSD-style license. See <a href="http://opentrafficsim.org/node/13">OpenTrafficSim License</a>.
   * <p>
   * @version $Revision$, $LastChangedDate$, by $Author$, initial version 2 feb. 2018 <br>
   * @author <a href="http://www.tbm.tudelft.nl/averbraeck">Alexander Verbraeck</a>
   * @author <a href="http://www.tudelft.nl/pknoppers">Peter Knoppers</a>
   * @author <a href="http://www.transport.citg.tudelft.nl">Wouter Schakel</a>
   * @param <K> key type
   * @param <V> value type
   * @param <M> navigable map type
   */
  public abstract class AbstractHistoricalNavigableMap<K, V, M extends NavigableMap<K, V>>
          extends AbstractHistoricalSortedMap<K, V, M> implements HistoricalNavigableMap<K, V>
  {
  
      /**
       * Constructor.
       * @param historyManager HistoryManager; history manager
       * @param map M; initial map
       */
      protected AbstractHistoricalNavigableMap(final HistoryManager historyManager, final M map)
      {
          super(historyManager, map);
      }
  
      // Altering NavigableMap methods
  
      /** {@inheritDoc} */
      @Override
      public Entry<K, V> pollFirstEntry()
      {
          if (getMap().isEmpty())
          {
              return null;
          }
          Entry<K, V> entry = Collections.unmodifiableNavigableMap(getMap()).firstEntry();
          remove(entry.getKey());
          return entry;
      }
  
      /** {@inheritDoc} */
      @Override
      public Entry<K, V> pollLastEntry()
      {
          if (getMap().isEmpty())
          {
              return null;
          }
          Entry<K, V> entry = Collections.unmodifiableNavigableMap(getMap()).lastEntry();
          remove(entry.getKey());
          return entry;
      }
  
      // Non-altering NavigableMap methods
  
      /** {@inheritDoc} */
      @Override
      public Entry<K, V> lowerEntry(final K key)
      {
          return Collections.unmodifiableNavigableMap(getMap()).lowerEntry(key);
      }
  
      /** {@inheritDoc} */
      @Override
      public K lowerKey(final K key)
      {
          return getMap().lowerKey(key);
      }
  
      /** {@inheritDoc} */
      @Override
      public Entry<K, V> floorEntry(final K key)
      {
          return Collections.unmodifiableNavigableMap(getMap()).floorEntry(key);
      }
  
      /** {@inheritDoc} */
      @Override
      public K floorKey(final K key)
      {
          return getMap().floorKey(key);
      }
  
      /** {@inheritDoc} */
      @Override
     public Entry<K, V> ceilingEntry(final K key)
     {
         return Collections.unmodifiableNavigableMap(getMap()).ceilingEntry(key);
     }
 
     /** {@inheritDoc} */
     @Override
     public K ceilingKey(final K key)
     {
         return getMap().ceilingKey(key);
     }
 
     /** {@inheritDoc} */
     @Override
     public Entry<K, V> higherEntry(final K key)
     {
         return Collections.unmodifiableNavigableMap(getMap()).higherEntry(key);
     }
 
     /** {@inheritDoc} */
     @Override
     public K higherKey(final K key)
     {
         return getMap().higherKey(key);
     }
 
     /** {@inheritDoc} */
     @Override
     public Entry<K, V> firstEntry()
     {
         return Collections.unmodifiableNavigableMap(getMap()).firstEntry();
     }
 
     /** {@inheritDoc} */
     @Override
     public Entry<K, V> lastEntry()
     {
         return Collections.unmodifiableNavigableMap(getMap()).lastEntry();
     }
 
     /** {@inheritDoc} */
     @Override
     public NavigableMap<K, V> descendingMap()
     {
         return Collections.unmodifiableNavigableMap(getMap().descendingMap());
     }
 
     /** {@inheritDoc} */
     @Override
     public NavigableSet<K> navigableKeySet()
     {
         return Collections.unmodifiableNavigableSet(getMap().navigableKeySet());
     }
 
     /** {@inheritDoc} */
     @Override
     public NavigableSet<K> descendingKeySet()
     {
         return Collections.unmodifiableNavigableSet(getMap().descendingKeySet());
     }
 
     /** {@inheritDoc} */
     @Override
     public NavigableMap<K, V> subMap(final K fromKey, final boolean fromInclusive, final K toKey, final boolean toInclusive)
     {
         return Collections.unmodifiableNavigableMap(getMap().subMap(fromKey, fromInclusive, toKey, toInclusive));
     }
 
     /** {@inheritDoc} */
     @Override
     public NavigableMap<K, V> headMap(final K toKey, final boolean inclusive)
     {
         return Collections.unmodifiableNavigableMap(getMap().headMap(toKey, inclusive));
     }
 
     /** {@inheritDoc} */
     @Override
     public NavigableMap<K, V> tailMap(final K fromKey, final boolean inclusive)
     {
         return Collections.unmodifiableNavigableMap(getMap().tailMap(fromKey, inclusive));
     }
 
 }