/*
    * 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.jstl.fn;
  
  import java.lang.reflect.Method;
  import java.lang.reflect.Modifier;
  import java.util.HashMap;
  import java.util.Map;
  
  import javax.faces.FacesException;
  import javax.faces.view.facelets.TagConfig;
  import javax.faces.view.facelets.TagHandler;
  
  import org.apache.myfaces.view.facelets.tag.TagLibrary;
  
  /**
   * Library for JSTL Functions
   * 
   * @author Jacob Hookom
   * @version $Id$
   */
  public class JstlFnLibrary implements TagLibrary
  {
      public final static String NAMESPACE = "http://xmlns.jcp.org/jsp/jstl/functions";
      public final static String ALIAS_NAMESPACE = "http://java.sun.com/jsp/jstl/functions";
  
      private final Map<String, Method> fns = new HashMap<String, Method>();
  
      public JstlFnLibrary()
      {
          super();
          try
          {
              Method[] methods = JstlFunction.class.getMethods();
              for (int i = 0; i < methods.length; i++)
              {
                  if (Modifier.isStatic(methods[i].getModifiers()))
                  {
                      fns.put(methods[i].getName(), methods[i]);
                  }
              }
          }
          catch (Exception e)
          {
              throw new RuntimeException(e);
          }
      }
  
      @Override
      public boolean containsNamespace(String ns)
      {
          return NAMESPACE.equals(ns) || ALIAS_NAMESPACE.equals(ns);
      }
  
      @Override
      public boolean containsTagHandler(String ns, String localName)
      {
          return false;
      }
  
      @Override
      public TagHandler createTagHandler(String ns, String localName, TagConfig tag) throws FacesException
      {
          return null;
      }
  
      @Override
      public boolean containsFunction(String ns, String name)
      {
          if (NAMESPACE.equals(ns) || ALIAS_NAMESPACE.equals(ns))
          {
              return this.fns.containsKey(name);
          }
          
          return false;
      }
  
      @Override
      public Method createFunction(String ns, String name)
      {
          if (NAMESPACE.equals(ns) || ALIAS_NAMESPACE.equals(ns))
          {
              return (Method) this.fns.get(name);
         }
         
         return null;
     }
 }