/*
 * Copyright (C) The Apache Software Foundation. All rights reserved.
 *
 * This software is published under the terms of the Apache Software License
 * version 1.1, a copy of which has been included  with this distribution in
 * the LICENSE.txt file.
 */

package org.apache.log4j.varia;

import org.apache.log4j.Level;
import org.apache.log4j.spi.Filter;
import org.apache.log4j.spi.LoggingEvent;
import org.apache.log4j.helpers.OptionConverter;

/**
   This is a very simple filter based on level matching.

   
The filter admits two options LevelToMatch and
   AcceptOnMatch. If there is an exact match between the value
   of the LevelToMatch option and the level of the {@link
   LoggingEvent}, then the {@link #decide} method returns {@link
   Filter#ACCEPT} in case the AcceptOnMatch option value is set
   to true, if it is false then {@link
   Filter#DENY} is returned. If there is no match, {@link
   Filter#NEUTRAL} is returned.

   @author Ceki Gülcü

   @since 1.2 */
public class LevelMatchFilter extends Filter {
  
  /**
     Do we return ACCEPT when a match occurs. Default is
     true.  */
  boolean acceptOnMatch = true;

  /**
   */
  Level levelToMatch;

 
  public
  void setLevelToMatch(String level) {
    levelToMatch = OptionConverter.toLevel(level, null);
  }
  
  public
  String getLevelToMatch() {
    return levelToMatch == null ? null : levelToMatch.toString();
  }
  
  public
  void setAcceptOnMatch(boolean acceptOnMatch) {
    this.acceptOnMatch = acceptOnMatch;
  }
  
  public
  boolean getAcceptOnMatch() {
    return acceptOnMatch;
  }
  

  /**
     Return the decision of this filter.

     Returns {@link Filter#NEUTRAL} if the LevelToMatch option
     is not set or if there is not match.  Otherwise, if there is a
     match, then the returned decision is {@link Filter#ACCEPT} if the
     AcceptOnMatch property is set to true. The
     returned decision is {@link Filter#DENY} if the
     AcceptOnMatch property is set to false.

  */
  public
  int decide(LoggingEvent event) {
    if(this.levelToMatch == null) {
      return Filter.NEUTRAL;
    }
    
    boolean matchOccured = false;
    if(this.levelToMatch.equals(event.getLevel())) {
      matchOccured = true;
    } 

    if(matchOccured) {  
      if(this.acceptOnMatch)
	  return Filter.ACCEPT;
      else
	  return Filter.DENY;
    } else {
      return Filter.NEUTRAL;
    }
  }
}