/*
    * 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.datalist;
  
  import java.util.Iterator;
  import java.util.Map;
  
  import javax.faces.component.UIComponent;
  import javax.faces.context.FacesContext;
  
  import org.apache.commons.logging.Log;
  import org.apache.commons.logging.LogFactory;
  import org.apache.myfaces.component.UserRoleAware;
  
  /**
   * Similar to dataTable, but does not render a table. 
   * 
   * Instead the layout attribute controls how each dataRow is rendered. 
   * 
   * Unless otherwise specified, all attributes accept static values or EL expressions.
   * 
   * @JSFComponent
   *   name = "t:dataList"
   *   class = "org.apache.myfaces.custom.datalist.HtmlDataList"
   *   tagClass = "org.apache.myfaces.custom.datalist.HtmlDataListTag"
   * @since 1.1.7
   * @author Manfred Geiler (latest modification by $Author: lu4242 $)
   * @version $Revision: 1327690 $ $Date: 2012-04-18 16:30:58 -0500 (Wed, 18 Apr 2012) $
   */
  public abstract class AbstractHtmlDataList
          extends org.apache.myfaces.component.html.ext.HtmlDataTableHack
          implements UserRoleAware
  {
      public static final String COMPONENT_TYPE = "org.apache.myfaces.HtmlDataList";
      private static final String DEFAULT_RENDERER_TYPE = "org.apache.myfaces.List";
          
      private static Log log = LogFactory.getLog(AbstractHtmlDataList.class);
      private static final int PROCESS_DECODES = 1;
      private static final int PROCESS_VALIDATORS = 2; // not currently in use
      private static final int PROCESS_UPDATES = 3; // not currently in use
  
      /**
       * Throws NullPointerException if context is null.  Sets row index to -1, 
       * calls processChildren, sets row index to -1.
       */
  
      public void processDecodes(FacesContext context)
      {
  
          if (context == null)
              throw new NullPointerException("context");
          if (!isRendered())
              return;
  
          setRowIndex(-1);
          processChildren(context, PROCESS_DECODES);
          setRowIndex(-1);
          try
          {
              decode(context);
          }
          catch (RuntimeException e)
          {
              context.renderResponse();
              throw e;
          }        
      }
  
      public void processUpdates(FacesContext context)
      {
          if (context == null)
              throw new NullPointerException("context");
          if (!isRendered())
              return;
  
          setRowIndex(-1);
          processChildren(context, PROCESS_UPDATES);
          setRowIndex(-1);
          checkUpdateModelError(context);
      }
  
      public void processValidators(FacesContext context)
      {
         if (context == null)
             throw new NullPointerException("context");
         if (!isRendered())
             return;
 
         setRowIndex(-1);
         processChildren(context, PROCESS_VALIDATORS);
         setRowIndex(-1);
         checkUpdateModelError(context);        
     }
 
     /**
      * Iterates over all children, processes each according to the specified 
      * process action if the child is rendered.
      */
 
     public void processChildren(FacesContext context, int processAction)
     {
         // use this method for processing other than decode ?
         int first = getFirst();
         int rows = getRows();
         int last = rows == 0 ? getRowCount() : first + rows;
 
         if (log.isTraceEnabled())
         {
             log.trace("processing " + getChildCount()
                             + " children: starting at " + first
                             + ", ending at " + last);
         }
 
         for (int rowIndex = first; last == -1 || rowIndex < last; rowIndex++)
         {
 
             setRowIndex(rowIndex);
 
             if (!isRowAvailable())
             {
                 if (log.isTraceEnabled())
                 {
                     log.trace("scrolled past the last row, aborting");
                 }
                 break;
             }
 
             for (Iterator it = getChildren().iterator(); it.hasNext();)
             {
                 UIComponent child = (UIComponent) it.next();
                 if (child.isRendered())
                     process(context, child, processAction);
             }
         }
     }
 
     /**
      * Copy and pasted from UIData in order to maintain binary compatibility.
      */
 
     private void process(FacesContext context, UIComponent component,
             int processAction)
     {
         switch (processAction)
         {
         case PROCESS_DECODES:
             component.processDecodes(context);
             break;
         case PROCESS_VALIDATORS:
             component.processValidators(context);
             break;
         case PROCESS_UPDATES:
             component.processUpdates(context);
             break;
         }
     }
     
     public void setRowIndex(int rowIndex)
     {
         super.setRowIndex(rowIndex);
         String rowIndexVar = getRowIndexVar();
         String rowCountVar = getRowCountVar();
         if (rowIndexVar != null || rowCountVar != null)
         {
             Map requestMap = FacesContext.getCurrentInstance().getExternalContext().getRequestMap();
             if (rowIndex >= 0)
             {
                 //regular row index, update request scope variables
                 if (rowIndexVar != null)
                 {
                     requestMap.put(getRowIndexVar(), new Integer(rowIndex));
                 }
                 if (rowCountVar != null)
                 {
                     requestMap.put(getRowCountVar(), new Integer(getRowCount()));
                 }
             }
             else
             {
                 //rowIndex == -1 means end of loop --> remove request scope variables
                 if (rowIndexVar != null)
                 {
                     requestMap.remove(getRowIndexVar());
                 }
                 if (rowCountVar != null)
                 {
                     requestMap.remove(getRowCountVar());
                 }
             }
         }
     }
 
     protected void restoreDescendantComponentStates(Object state)
     {
         restoreDescendantComponentStates(getChildren().iterator(), state, true);
     }
 
     protected Object saveDescendantComponentStates()
     {
         return saveDescendantComponentStates(getChildren().iterator(), true);
     }
 
     /**
      * A parameter name, under which the rowCount is set in request 
      * scope similar to the var parameter.
      * 
      * @JSFProperty
      */
     public abstract String getRowCountVar();
     
     /**
      *  A parameter name, under which the current rowIndex is set in 
      *  request scope similar to the var parameter.
      * 
      * @JSFProperty
      */
     public abstract String getRowIndexVar();
 
     /**
      * simple|unorderedList|orderedList
      * <ul>
      *   <li>simple = for each dataRow all children are simply rendered</li>
      *   <li>unorderedList = the list is rendered as HTML unordered list (= bullet list)</li>
      *   <li>orderedList = the list is rendered as HTML ordered list</li>
      * </ul>
      * Default: simple
      * 
      * @JSFProperty
      */
     public abstract String getLayout();
     
     /**
      * CSS class to be applied to individual items in the list
      * 
      * @JSFProperty
      */
     public abstract String getItemStyleClass();
     
     /**
      * OnClick handler to be applied to individual items in the list
      * 
      * @JSFProperty
      */
     public abstract String getItemOnClick();
 }