/*
    * Copyright (c) 2009 QOS.ch All rights reserved.
    * 
    * Permission is hereby granted, free of charge, to any person obtaining a copy
    * of this software and associated documentation files (the "Software"), to deal
    * in the Software without restriction, including without limitation the rights
    * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
    * copies of the Software, and to permit persons to whom the Software is
    * furnished to do so, subject to the following conditions:
   * 
   * The above copyright notice and this permission notice shall be included in
   * all copies or substantial portions of the Software.
   * 
   * THE SOFTWARE IS PROVIDED "AS  IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
   * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
   * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
   * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
   * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
   * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
   * SOFTWARE.
   */
  package ch.qos.cal10n.util;
  
  import java.io.File;
  import java.io.IOException;
  import java.io.Reader;
  import java.util.Enumeration;
  import java.util.Hashtable;
  import java.util.Map;
  import java.util.ResourceBundle;
  import java.util.concurrent.ConcurrentHashMap;
  
  /**
   * 
   * @author Ceki Gülcü
   *
   */
  public class CAL10NBundle extends ResourceBundle {
  
    static long CHECK_DELAY = 10 * 60 * 1000; // 10 minutes delay
  
    Map<String, String> map = new ConcurrentHashMap<String, String>();
    File hostFile;
    volatile long nextCheck;
    long lastModified;
    CAL10NBundle parent;
    
    public CAL10NBundle(Reader r, File file)
        throws IOException {
      read(r);
      this.hostFile = file;
      nextCheck = System.currentTimeMillis() + CHECK_DELAY;
    }
  
    void read(Reader r) throws IOException {
      Parser p = new Parser(r, map);
      p.parseAndPopulate();
    }
  
  
    public void setParent(CAL10NBundle parent) {
      this.parent = (parent);
    }
  
    public boolean hasChanged() {
      // if the host file is unknown, no point in a check
      if (hostFile == null) {
        return false;
      }
  
      long now = System.currentTimeMillis();
      if (now < nextCheck) {
        return false;
      } else {
        nextCheck = now + CHECK_DELAY;
        if (lastModified != hostFile.lastModified()) {
          lastModified = hostFile.lastModified();
          return true;
        } else {
          return false;
        }
      }
    }
  
    /**
     * WARNING: Used for testing purposes. Do not invoke directly in user code.
     */
    public void resetCheckTimes() {
      nextCheck = 0;
      lastModified = 0;
    } 
  
    @Override
    public Enumeration<String> getKeys() {
      Hashtable<String, String> ht = new Hashtable<String, String>(map);
      if(parent != null) {
        ht.putAll(parent.map);
      }
      return ht.keys();
   }
 
   @Override
   protected Object handleGetObject(String key) {
     if (key == null) {
       throw new NullPointerException();
     }
     Object o = map.get(key);
     if(o == null && parent != null) {
       o = parent.handleGetObject(key);
     }
     return o;
   }
 }