/*
    * 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.custom.tree.taglib;
  
  import java.io.IOException;
  
  import javax.el.ELException;
  import javax.faces.FacesException;
  import javax.faces.component.UIComponent;
  import javax.faces.view.facelets.FaceletContext;
  import javax.faces.view.facelets.FaceletException;
  import javax.faces.view.facelets.TagAttribute;
  import javax.faces.view.facelets.TagConfig;
  import javax.faces.view.facelets.TagHandler;
  
  import org.apache.myfaces.custom.tree.HtmlTree;
  import org.apache.myfaces.custom.tree.event.TreeSelectionListener;
  import org.apache.myfaces.shared_tomahawk.util.ClassUtils;
  
  /**
   * 
   * @since 1.1.7
   */
  public class TreeSelectionListenerTagHandler extends TagHandler
  {
  
      private final TagAttribute typeAttr;
      
      public TreeSelectionListenerTagHandler(TagConfig config)
      {
          super(config);
          typeAttr = getRequiredAttribute("type");
      }
  
      public void apply(FaceletContext faceletContext, UIComponent parent)
              throws IOException, FacesException, FaceletException, ELException
      {
          if (parent.getParent() == null)
          {
              if (parent instanceof HtmlTree)
              {
                  String className;
                  if (!typeAttr.isLiteral())
                  {
                      className = typeAttr.getValue();
                  }
                  else
                  {
                      className = typeAttr.getValue(faceletContext);
                  }
                  TreeSelectionListener listener = (TreeSelectionListener) ClassUtils.newInstance(className);
                  ((HtmlTree) parent).addTreeSelectionListener(listener);
              }
              else
              {
                  throw new FacesException(
                          "Component is not HtmlTree children");
              }            
          }
      }
  }