/**
    * Copyright 2005-2015 The Kuali Foundation
    *
    * Licensed under the Educational Community 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.opensource.org/licenses/ecl2.php
    *
   * 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.kuali.rice.krms.api.repository;
  
  import java.lang.reflect.InvocationTargetException;
  import java.util.ArrayList;
  import java.util.Collections;
  import java.util.HashSet;
  import java.util.List;
  import java.util.Set;
  
  import org.apache.commons.collections.CollectionUtils;
  import org.kuali.rice.core.api.exception.RiceRuntimeException;
  import org.kuali.rice.core.api.mo.ModelBuilder;
  import org.kuali.rice.core.api.mo.ModelObjectComplete;
  
  /**
   * Utilities for implementing {@link ModelBuilder}s more easily.
   * 
   * @author Kuali Rice Team (rice.collab@kuali.org)
   *
   */
  public class BuilderUtils {
  	
  	private static final String COULDNT_INVOKE_BUILDER_CREATE = "couldn't invoke Builder.create()";
  
  
  	@SuppressWarnings("unchecked")
  	public static <B> List<B> convertFromBuilderList(List<? extends ModelBuilder> toConvert) {
  		if (CollectionUtils.isEmpty(toConvert)) {
  			return Collections.emptyList();
  		} else {
  			List<B> results = new ArrayList<B>(toConvert.size());
  			for (ModelBuilder elem : toConvert) {
  				results.add((B)elem.build());
  			}
  			return Collections.unmodifiableList(results);
  		}
  	} 
  	
  	@SuppressWarnings("unchecked")
  	public static <B> Set<B> convertFromBuilderSet(Set<? extends ModelBuilder> toConvert) {
  		if (CollectionUtils.isEmpty(toConvert)) {
  			return Collections.emptySet();
  		} else {
  			Set<B> results = new HashSet<B>(toConvert.size());
  			for (ModelBuilder elem : toConvert) {
  				results.add((B)elem.build());
  			}
  			return Collections.unmodifiableSet(results);
  		}
  	} 
  	
  	/**
  	 * This method is useful for converting a List&lt;? extends BlahContract&gt; to a 
  	 * List&lt;Blah.Builder&gt;.  You'll just need to implement Transformer to use it.
  	 * 
  	 * @param <A>
  	 * @param <B>
  	 * @param toConvert
  	 * @param xform
  	 * @return
  	 */
  	public static <A,B> List<B> transform(List<? extends A> toConvert, Transformer<A,B> xform) {
  		if (CollectionUtils.isEmpty(toConvert)) {
  			return new ArrayList<B>();
  		} else {
  			List<B> results = new ArrayList<B>(toConvert.size());
  			for (A elem : toConvert) {
  				results.add(xform.transform(elem));
  			}
  			return results;
  		}
  	}
  	
  	public static <A,B> Set<B> transform(Set<? extends A> toConvert, Transformer<A,B> xform) {
  		if (CollectionUtils.isEmpty(toConvert)) {
  			return new HashSet<B>();
  		} else {
  			Set<B> results = new HashSet<B>(toConvert.size());
  			for (A elem : toConvert) {
  				results.add(xform.transform(elem));
  			}
  			return results;
  		}
  	}
 	
 	public interface Transformer<A,B> {
 		public B transform(A input);
 	}
 	
 }