/*
    * 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.myfaces.component.search;
  
  import java.util.List;
  import javax.faces.component.UIComponent;
  import javax.faces.component.search.UntargetableComponent;
  import javax.faces.component.search.SearchExpressionContext;
  import javax.faces.component.search.SearchKeywordContext;
  import javax.faces.component.search.SearchKeywordResolver;
  
  /**
   *
   */
  public class PreviousSearchKeywordResolver extends SearchKeywordResolver
  {
      public static final String PREVIOUS_KEYWORD = "previous";
  
      @Override
      public void resolve(SearchKeywordContext expressionContext, UIComponent current, String keyword)
      {
          UIComponent parent = current.getParent();
  
          if (parent.getChildCount() > 1)
          {
              List<UIComponent> children = parent.getChildren();
              int index = children.indexOf(current);
  
              if (index > 0)
              {
                  int nextIndex = -1;
                  do
                  {
                      index--;
                      if(!(children.get(index) instanceof UntargetableComponent))
                      {
                          nextIndex = index;
                      }
                  } while (nextIndex == -1 && index > 0);
  
                  if (nextIndex != -1)
                  {
                      expressionContext.invokeContextCallback(children.get(nextIndex));
                  }
              }
          }
          expressionContext.setKeywordResolved(true);
      }
      
      @Override
      public boolean isResolverForKeyword(SearchExpressionContext searchExpressionContext, String keyword)
      {
          return PREVIOUS_KEYWORD.equalsIgnoreCase(keyword);
      }
  
      @Override
      public boolean isPassthrough(SearchExpressionContext searchExpressionContext, String keyword)
      {
          return false;
      }
      
      @Override
      public boolean isLeaf(SearchExpressionContext searchExpressionContext, String keyword)
      {
          return false;
      }
  
  }