/*
    * 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.compiler;
  
  import java.util.ArrayList;
  import java.util.List;
  
  import org.apache.myfaces.view.facelets.tag.TagLibrary;
  
  /**
   * @author Jacob Hookom
   * @version $Id$
   */
  final class NamespaceManager
  {
  
      private final static class NS
      {
          public final String prefix;
  
          public final String namespace;
  
          public NS(String prefix, String ns)
          {
              this.prefix = prefix;
              this.namespace = ns;
          }
      }
  
      private final List<NS> namespaces;
  
      /**
       * 
       */
      public NamespaceManager()
      {
          this.namespaces = new ArrayList<NS>();
      }
  
      public void reset()
      {
          this.namespaces.clear();
      }
  
      public void pushNamespace(String prefix, String namespace)
      {
          NS ns = new NS(prefix, namespace);
          this.namespaces.add(0, ns);
      }
  
      public String getNamespace(String prefix)
      {
          NS ns = null;
          for (int i = 0; i < this.namespaces.size(); i++)
          {
              ns = (NS) this.namespaces.get(i);
              if (ns.prefix.equals(prefix))
              {
                  return ns.namespace;
              }
          }
          return null;
      }
  
      public void popNamespace(String prefix)
      {
          NS ns = null;
          for (int i = 0; i < this.namespaces.size(); i++)
          {
              ns = (NS) this.namespaces.get(i);
              if (ns.prefix.equals(prefix))
              {
                  this.namespaces.remove(i);
                  return;
              }
          }
      }
  
      public NamespaceUnit toNamespaceUnit(TagLibrary library)
      {
          NamespaceUnit unit = new NamespaceUnit(library);
          if (this.namespaces.size() > 0)
          {
             NS ns = null;
             for (int i = this.namespaces.size() - 1; i >= 0; i--)
             {
                 ns = this.namespaces.get(i);
                 unit.setNamespace(ns.prefix, ns.namespace);
             }
         }
         return unit;
     }
 
 }