/*
    * 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.jslistener;
  
  import java.io.IOException;
  
  import javax.faces.application.Application;
  import javax.faces.application.ResourceDependency;
  import javax.faces.component.UIComponent;
  import javax.faces.component.UINamingContainer;
  import javax.faces.context.FacesContext;
  
  import org.apache.commons.logging.Log;
  import org.apache.commons.logging.LogFactory;
  import org.apache.myfaces.shared_tomahawk.renderkit.RendererUtils;
  import org.apache.myfaces.shared_tomahawk.renderkit.html.HtmlRenderer;
  
  /**
   * @JSFRenderer
   *   renderKitId = "HTML_BASIC" 
   *   family = "javax.faces.Output"
   *   type = "org.apache.myfaces.JsValueChangeListener"
   * 
   * @author Martin Marinschek (latest modification by $Author: skitching $)
   * @version $Revision: 673833 $ $Date: 2008-07-03 16:58:05 -0500 (jue, 03 jul 2008) $
   */
  @ResourceDependency(library="oam.custom.jslistener",name="JSListener.js")
  public class JsValueChangeListenerRenderer
          extends HtmlRenderer
  {
      private static Log log = LogFactory.getLog(JsValueChangeListenerRenderer.class);
  
      public void encodeEnd(FacesContext facesContext, UIComponent component)
              throws IOException
      {
          RendererUtils.checkParamValidity(facesContext, component, JsValueChangeListener.class);
  
          UIComponent parent = component.getParent();
  
          JsValueChangeListener jsValueChangeListener = (JsValueChangeListener) component;
  
  
          String aFor = jsValueChangeListener.getFor();
          String expressionValue = jsValueChangeListener.getExpressionValue();
          String property = jsValueChangeListener.getProperty();
  
          //AddResourceFactory.getInstance(facesContext).addJavaScriptAtPosition(
          //        facesContext, AddResource.HEADER_BEGIN, JsValueChangeListenerRenderer.class,
          //        "JSListener.js");
  
          if(aFor!=null)
          {
              UIComponent forComponent = component.findComponent(aFor);
  
              String forComponentId = null;
  
              if (forComponent == null)
              {
                  if (log.isInfoEnabled())
                  {
                      log.info("Unable to find component '" + aFor + "' (calling findComponent on component '" + component.getClientId(getFacesContext()) + "') - will try to render component id based on the parent-id (on same level)");
                  }
                  if (aFor.length() > 0 && aFor.charAt(0) == UINamingContainer.SEPARATOR_CHAR)
                  {
                      //absolute id path
                      forComponentId = aFor.substring(1);
                  }
                  else
                  {
                      //relative id path, we assume a component on the same level as the label component
                      String labelClientId = component.getClientId(getFacesContext());
                      int colon = labelClientId.lastIndexOf(UINamingContainer.SEPARATOR_CHAR);
                      if (colon == -1)
                      {
                          forComponentId = aFor;
                      }
                      else
                      {
                          forComponentId = labelClientId.substring(0, colon + 1) + aFor;
                      }
                  }
              }
              else
             {
                 forComponentId = forComponent.getClientId(getFacesContext());
             }
 
             expressionValue = expressionValue.replaceAll("\\'","\\\\'");
             expressionValue = expressionValue.replaceAll("\"","\\\"");
 
 
             String methodCall = "orgApacheMyfacesJsListenerSetExpressionProperty('"+
                     parent.getClientId(getFacesContext())+"','"+
                     forComponentId+"',"+
                     (property==null?"null":"'"+property+"'")+
                     ",'"+expressionValue+"');";
 
 
             callMethod(facesContext, jsValueChangeListener, "onchange",methodCall);
 
             if (jsValueChangeListener.getBodyTagEvent() != null)
             {
                 callMethod(facesContext, jsValueChangeListener, jsValueChangeListener.getBodyTagEvent(), methodCall);
             }
 
         }
     }
 
     private void callMethod(FacesContext context, JsValueChangeListener jsValueChangeListener, String propName, String value)
     {
         UIComponent parent = jsValueChangeListener.getParent();
 
         Object oldValue = parent.getAttributes().get(propName);
         
         if(oldValue != null)
         {
             String oldValueStr = oldValue.toString().trim();
 
             // render the jsValueChangeListener script only for each parent component 
             if(oldValueStr.indexOf(parent.getClientId(FacesContext.getCurrentInstance())) < 0
                     && oldValueStr.length() > 0)
             {
                 oldValueStr = "";
             }
 
             if(oldValueStr.length()>0 && !oldValueStr.endsWith(";"))
                 oldValueStr +=";";
 
             value = oldValueStr + value;
 
         }
 
         if (!propName.equals("onchange") && value != null)
         {
             //TODO: this should be refactored to register a javascript-event-wrapper the java-script way
             //in the current version of AddResource, this would not work anymore
             /*AddResourceFactory.getInstance(context).
                     addJavaScriptToBodyTag(context,jsValueChangeListener.getBodyTagEvent(), value);*/
         }
         else if(value != null)
         {
             parent.getAttributes().put(propName, value);
         }
         else
         {
             try
             {
                 parent.getAttributes().remove(propName);
             }
             catch(Exception ex)
             {
                 log.error("the value could not be removed : ",ex);
             }
         }
     }
 
 
     protected Application getApplication()
     {
         return getFacesContext().getApplication();
     }
 
     protected FacesContext getFacesContext()
     {
         return FacesContext.getCurrentInstance();
     }
 
 }