package fr.ifremer.tutti.persistence.entities;
   
   /*
    * #%L
    * Tutti :: Persistence
    * %%
    * Copyright (C) 2012 - 2014 Ifremer
    * %%
    * This program is free software: you can redistribute it and/or modify
   * it under the terms of the GNU General Public License as
   * published by the Free Software Foundation, either version 3 of the 
   * License, or (at your option) any later version.
   * 
   * This program is distributed in the hope that it will be useful,
   * but WITHOUT ANY WARRANTY; without even the implied warranty of
   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   * GNU General Public License for more details.
   * 
   * You should have received a copy of the GNU General Public 
   * License along with this program.  If not, see
   * <http://www.gnu.org/licenses/gpl-3.0.html>.
   * #L%
   */
  
  import com.google.common.base.Function;
  import com.google.common.base.Predicate;
  import com.google.common.collect.Iterables;
  import com.google.common.collect.Lists;
  import com.google.common.collect.Maps;
  
  import java.util.Collection;
  import java.util.Collections;
  import java.util.List;
  import java.util.Map;
  
  /**
   * Usefull method around tutti entities.
   *
   * @author Tony Chemit - chemit@codelutin.com
   * @since 0.1
   */
  public class TuttiEntities {
  
      protected TuttiEntities() {
          // helper class does not instanciate
      }
  
  //    public static <B extends TuttiEntity> List<String> toIds(Collection<B> list) {
  //        return list == null ?
  //                              Collections.<String>emptyList() :
  //                              Lists.transform(list instanceof List? (List<B>)list: new ArrayList<>(list), GET_ID);
  //    }
  
      public static <B extends TuttiEntity> List<Integer> toIntegerIds(Collection<B> list) {
          return list == null ?
                                 Collections.<Integer>emptyList() :
                                 Lists.transform(Lists.newArrayList(list), GET_ID_AS_INT);
      }
  
      public static <B extends TuttiEntity> Map<String, B> splitById(Iterable<B> list) {
          return Maps.uniqueIndex(list, GET_ID);
      }
  
      public static <B extends TuttiEntity> Map<Integer, B> splitByIdAsInt(Iterable<B> list) {
          return Maps.uniqueIndex(list, GET_ID_AS_INT);
      }
  
      public static <B extends TuttiEntity> boolean isNew(B bean) {
          return bean.getId() == null;
      }
  
      public static final Function<TuttiEntity, String> GET_ID = TuttiEntity::getId;
  
      public static <E extends TuttiEntity> Function<E, String> newIdFunction() {
          return (Function<E, String>) GET_ID;
      }
  
      public static <E extends TuttiEntity> Function<E, Integer> newIdAstIntFunction() {
          return (Function<E, Integer>) GET_ID_AS_INT;
      }
  
      public static final Function<TuttiEntity, Integer> GET_ID_AS_INT = TuttiEntity::getIdAsInt;
  
      public static <B extends TuttiEntity> Predicate<B> newIdPredicate(String id) {
          return new IdPredicate<>(id);
      }
  
      public static <B extends TuttiEntity> B findById(Iterable<B> beans, String id) {
          return Iterables.tryFind(beans, newIdPredicate(id)).orNull();
      }
  
      public static <B extends TuttiEntity> List<String> collecIds(List<B> list) {
          return Lists.transform(list, GET_ID);
      }
  
      protected static class IdPredicate<B extends TuttiEntity> implements Predicate<B> {
  
          private final String id;
  
         public IdPredicate(String id) {
             this.id = id;
         }
 
         @Override
         public boolean apply(B input) {
             return id.equals(input.getId());
         }
     }
 
 }