/*
    * 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.view.facelets.tag.ui;
  
  import java.io.IOException;
  import java.util.Collection;
  import java.util.HashMap;
  import java.util.Map;
  import java.util.logging.Level;
  import java.util.logging.Logger;
  
  import javax.el.ELException;
  import javax.faces.FacesException;
  import javax.faces.application.StateManager;
  import javax.faces.component.UIComponent;
  import javax.faces.event.PhaseId;
  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.buildtools.maven2.plugin.builder.annotation.JSFFaceletAttribute;
  import org.apache.myfaces.buildtools.maven2.plugin.builder.annotation.JSFFaceletTag;
  import org.apache.myfaces.view.facelets.AbstractFaceletContext;
  import org.apache.myfaces.view.facelets.FaceletCompositionContext;
  import org.apache.myfaces.view.facelets.TemplateClient;
  import org.apache.myfaces.view.facelets.tag.ComponentContainerHandler;
  import org.apache.myfaces.view.facelets.tag.TagHandlerUtils;
  import org.apache.myfaces.view.facelets.tag.jsf.ComponentSupport;
  
  /**
   * The decorate tag acts the same as a composition tag, but it will not trim 
   * everything outside of it. This is useful in cases where you have a list of 
   * items in a document, which you would like to be decorated or framed.
   *  
   * The sum of it all is that you can take any element in the document and decorate 
   * it with some external logic as provided by the template.
   * 
   * TODO: REFACTOR - This class could easily use a common parent with CompositionHandler
   * 
   * @author Jacob Hookom
   * @version $Id$
   */
  @JSFFaceletTag(name="ui:decorate")
  public final class DecorateHandler extends TagHandler implements TemplateClient, ComponentContainerHandler
  {
  
      private static final Logger log = Logger.getLogger(DecorateHandler.class.getName());
  
      /**
       * The resolvable URI of the template to use. The content within the decorate tag 
       * will be used in populating the template specified.
       */
      @JSFFaceletAttribute(
              name="template",
              className="javax.el.ValueExpression",
              deferredValueType="java.lang.String")
      private final TagAttribute _template;
  
      private final Map<String, DefineHandler> _handlers;
  
      private final ParamHandler[] _params;
  
      /**
       * @param config
       */
      public DecorateHandler(TagConfig config)
      {
          super(config);
          _template = getRequiredAttribute("template");
          _handlers = new HashMap<String, DefineHandler>();
  
          for (DefineHandler handler : TagHandlerUtils.findNextByType(nextHandler, DefineHandler.class))
          {
              _handlers.put(handler.getName(), handler);
              if (log.isLoggable(Level.FINE))
              {
                  log.fine(tag + " found Define[" + handler.getName() + "]");
              }
          }
  
          Collection<ParamHandler> params = TagHandlerUtils.findNextByType(nextHandler, ParamHandler.class);
         if (!params.isEmpty())
         {
             int i = 0;
             _params = new ParamHandler[params.size()];
             for (ParamHandler handler : params)
             {
                 _params[i++] = handler;
             }
         }
         else
         {
             _params = null;
         }
     }
 
     /*
      * (non-Javadoc)
      * 
      * @see javax.faces.view.facelets.FaceletHandler#apply(javax.faces.view.facelets.FaceletContext,
      * javax.faces.component.UIComponent)
      */
     @Override
     public void apply(FaceletContext ctx, UIComponent parent) throws IOException, FacesException, FaceletException,
             ELException
     {
         //VariableMapper orig = ctx.getVariableMapper();
         //if (_params != null)
         //{
         //    VariableMapper vm = new VariableMapperWrapper(orig);
         //    ctx.setVariableMapper(vm);
         //    for (int i = 0; i < _params.length; i++)
         //    {
         //        _params[i].apply(ctx, parent);
         //    }
         //}
 
         AbstractFaceletContext actx = (AbstractFaceletContext) ctx;
         actx.pushClient(this);
         FaceletCompositionContext fcc = FaceletCompositionContext.getCurrentInstance(ctx);
         String uniqueId = null;
         try
         {
             if (!_template.isLiteral())
             {
                 uniqueId = actx.generateUniqueFaceletTagId(
                     fcc.startComponentUniqueIdSection(), tagId);
             }
             else if (_params != null)
             {
                 uniqueId = actx.generateUniqueFaceletTagId(
                     fcc.generateUniqueComponentId(), tagId);
             }
             if (_params != null)
             {
                 //VariableMapper vm = new VariableMapperWrapper(orig);
                 //ctx.setVariableMapper(vm);
                 for (int i = 0; i < _params.length; i++)
                 {
                     _params[i].apply(ctx, parent, _params[i].getName(ctx), _params[i].getValue(ctx), uniqueId);
                 }
             }
 
             String path;
             boolean markInitialState = false;
             if (!_template.isLiteral())
             {
                 //String uniqueId = fcc.startComponentUniqueIdSection();
                 //path = getTemplateValue(actx, fcc, parent, uniqueId);
                 String restoredPath = (String) ComponentSupport.restoreInitialTagState(ctx, fcc, parent, uniqueId);
                 if (restoredPath != null)
                 {
                     // If is not restore view phase, the path value should be
                     // evaluated and if is not equals, trigger markInitialState stuff.
                     if (!PhaseId.RESTORE_VIEW.equals(ctx.getFacesContext().getCurrentPhaseId()))
                     {
                         path = this._template.getValue(ctx);
                         if (path == null || path.length() == 0)
                         {
                             return;
                         }
                         if (!path.equals(restoredPath))
                         {
                             markInitialState = true;
                         }
                     }
                     else
                     {
                         path = restoredPath;
                     }
                 }
                 else
                 {
                     //No state restored, calculate path
                     path = this._template.getValue(ctx);
                 }
                 ComponentSupport.saveInitialTagState(ctx, fcc, parent, uniqueId, path);
             }
             else
             {
                 path = _template.getValue(ctx);
             }
             try
             {
                 boolean oldMarkInitialState = false;
                 Boolean isBuildingInitialState = null;
                 if (markInitialState)
                 {
                     //set markInitialState flag
                     oldMarkInitialState = fcc.isMarkInitialState();
                     fcc.setMarkInitialState(true);
                     isBuildingInitialState = (Boolean) ctx.getFacesContext().getAttributes().put(
                             StateManager.IS_BUILDING_INITIAL_STATE, Boolean.TRUE);
                 }
                 try
                 {
                     ctx.includeFacelet(parent, path);
                 }
                 finally
                 {
                     if (markInitialState)
                     {
                         //unset markInitialState flag
                         if (isBuildingInitialState == null)
                         {
                             ctx.getFacesContext().getAttributes().remove(
                                     StateManager.IS_BUILDING_INITIAL_STATE);
                         }
                         else
                         {
                             ctx.getFacesContext().getAttributes().put(
                                     StateManager.IS_BUILDING_INITIAL_STATE, isBuildingInitialState);
                         }
                         fcc.setMarkInitialState(oldMarkInitialState);
                     }
                 }
             }
             finally
             {
                 //ctx.setVariableMapper(orig);
                 actx.popClient(this);
             }
         }
         finally
         {
             if (!_template.isLiteral())
             {
                 fcc.endComponentUniqueIdSection();
             }
         }
         if (!_template.isLiteral() && fcc.isUsingPSSOnThisView() && fcc.isRefreshTransientBuildOnPSS() &&
             !fcc.isRefreshingTransientBuild())
         {
             //Mark the parent component to be saved and restored fully.
             ComponentSupport.markComponentToRestoreFully(ctx.getFacesContext(), parent);
         }
         if (!_template.isLiteral() && fcc.isDynamicComponentSection())
         {
             ComponentSupport.markComponentToRefreshDynamically(ctx.getFacesContext(), parent);
         }
     }
 
     @Override
     public boolean apply(FaceletContext ctx, UIComponent parent, String name) throws IOException, FacesException,
             FaceletException, ELException
     {
         if (name != null)
         {
             DefineHandler handler = _handlers.get(name);
             if (handler != null)
             {
                 handler.applyDefinition(ctx, parent);
                 return true;
             }
             else
             {
                 return false;
             }
         }
         else
         {
             this.nextHandler.apply(ctx, parent);
             return true;
         }
     }
 }