/*
    * 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 javax.faces.application.Application;
  import javax.faces.component.UIComponent;
  import javax.faces.context.FacesContext;
  import javax.faces.el.ValueBinding;
  import javax.faces.webapp.UIComponentTag;
  
  import org.apache.myfaces.custom.tree.HtmlTree;
  import org.apache.myfaces.custom.tree.model.DefaultTreeModel;
  import org.apache.myfaces.custom.tree.model.TreeModel;
  import org.apache.myfaces.custom.tree.model.TreePath;
  
  import com.sun.facelets.FaceletContext;
  import com.sun.facelets.tag.TagAttribute;
  import com.sun.facelets.tag.jsf.ComponentConfig;
  import com.sun.facelets.tag.jsf.html.HtmlComponentHandler;
  
  /**
   * 
   * @since 1.1.7
   */
  public class TreeTagHandler extends HtmlComponentHandler
  {
  
      private TagAttribute valueAttr;
      private TagAttribute expandRootAttr;
      
      private boolean expandRoot;
      
      public TreeTagHandler(ComponentConfig config)
      {
          super(config);
          valueAttr = getRequiredAttribute("value");
          expandRootAttr = getRequiredAttribute("expandRoot");
          expandRoot = false;
      }
      
      protected void setAttributes(FaceletContext ctx, Object instance)
      {
          super.setAttributes(ctx, instance);
          
          Application app = ctx.getFacesContext().getApplication();
          
          HtmlTree tree = (HtmlTree) instance;
          
          if(valueAttr != null)
          {
              String value = valueAttr.getValue();
              if (value != null && UIComponentTag.isValueReference(value))
              {
                  tree.setValueBinding("model", app.createValueBinding(valueAttr
                          .getValue()));
              }
          }
          else
          {
              ValueBinding binding = tree.getValueBinding("model");
              if (binding == null) {
                  binding = app.createValueBinding("#{sessionScope.tree}");
              }
              tree.setValueBinding("model", binding);            
          }
          
          if (expandRootAttr != null)
          {
              expandRoot = expandRootAttr.getBoolean(ctx);
          }
      }
      
      protected void onComponentCreated(FaceletContext ctx,
              UIComponent component, UIComponent parent)
      {
          FacesContext context = ctx.getFacesContext();
          Application app = ctx.getFacesContext().getApplication();
          
          if (valueAttr != null) {
              String value = valueAttr.getValue();
              if (value != null){
                  ValueBinding valueBinding = app.createValueBinding(value);
                  TreeModel treeModel = (TreeModel) (valueBinding.getValue(context));
         
                 if (treeModel == null) {
                     // create default model
                     treeModel = new DefaultTreeModel();
                     valueBinding.setValue(context, treeModel);
                 }
             }
         }
         
         HtmlTree tree = (HtmlTree) component;
         
         if (expandRoot)
         {
             // component was created, so expand the root node
             TreeModel model = tree.getModel(context);
     
             if (model != null) {
                 tree.expandPath(new TreePath(new Object[] { model.getRoot() }),
                         context);
             }
         }
         tree.addToModelListeners();
     }
     
 }