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  package org.apache.james.smtpserver.core.filter.fastfail;
  
  import java.util.Iterator;
  import java.util.Map;
  
  import javax.mail.MessagingException;
  import javax.mail.internet.MimeMessage;
  
  import org.apache.avalon.framework.configuration.Configurable;
  import org.apache.avalon.framework.configuration.Configuration;
  import org.apache.avalon.framework.configuration.ConfigurationException;
  import org.apache.avalon.framework.logger.AbstractLogEnabled;
  import org.apache.james.dsn.DSNStatus;
  import org.apache.james.smtpserver.ConnectHandler;
  import org.apache.james.smtpserver.MessageHandler;
  import org.apache.james.smtpserver.SMTPSession;
  import org.apache.james.smtpserver.junkscore.ComposedJunkScore;
  import org.apache.james.smtpserver.junkscore.JunkScore;
  import org.apache.james.smtpserver.junkscore.JunkScoreImpl;
  
  /**
   * Check if a configured JunkScore is reached and perform an action. Valid actions are: reject, compose, header. 
   * 
   * -Reject action reject the mail if the limit is reached.
   * -Compose action stores the junkScore values in the mail attributes
   * -Header action create headers which holds the junkScore for each check
   */
  public class JunkScoreHandler extends AbstractLogEnabled implements ConnectHandler, MessageHandler,Configurable {
  
      private double maxScore = 0;
      private String action;
      private static final String REJECT_ACTION = "reject";
      private static final String COMPOSE_ACTION = "compose";
      private static final String HEADER_ACTION = "header";
  
      /**
       * @see org.apache.avalon.framework.configuration.Configurable#configure(org.apache.avalon.framework.configuration.Configuration)
       */
      public void configure(Configuration arg0) throws ConfigurationException {
          Configuration maxScoreConfig = arg0.getChild("maxScore");
  
          if (maxScoreConfig != null) {
              setMaxScore(maxScoreConfig.getValueAsDouble(0));
          }
          
          Configuration actionConfig = arg0.getChild("action");
          if (actionConfig != null) {
              setAction(actionConfig.getValue().toLowerCase());
          } else {
              throw new ConfigurationException("Please configure the action");
          }
      }
      
      /**
       * Set the max JunkScore
       * 
       * @param maxScore the score
       */
      public void setMaxScore(double maxScore) {
          this.maxScore = maxScore;
      }
      
      /**
       * Set the action to perform if the JunkScore limit is reached
       * 
       * @param action the action
       * @throws ConfigurationException if invalid action is used
       */
      public void setAction(String action) throws ConfigurationException {
          if (!action.equals(REJECT_ACTION) && !action.equals(COMPOSE_ACTION) && !action.equals(HEADER_ACTION)) 
              throw new ConfigurationException("Illegal action: " + action);
       
          this.action = action;  
      }
      
      /**
       * @see org.apache.james.smtpserver.MessageHandler#onMessage(org.apache.james.smtpserver.SMTPSession)
      */
     public void onMessage(SMTPSession session) {
         checkScore(session);
     }
 
     /**
      * Check if the JunkScore limit is reached and perform the configured action
      * 
      * @param session the SMTPSession
      */
     private void checkScore(SMTPSession session) {
         JunkScore score1 = (JunkScore) session.getConnectionState().get(JunkScore.JUNK_SCORE_SESSION);
         JunkScore score2 = (JunkScore) session.getState().get(JunkScore.JUNK_SCORE);
         JunkScore composed = new ComposedJunkScore(score1,score2);
         
         if (action.equals(COMPOSE_ACTION)) {
             // Save the scores attribute to maybe use it later!
             session.getMail().setAttribute(JunkScore.JUNK_SCORE_SESSION_ATTR, String.valueOf(score1.getCompleteStoredScores()));
             session.getMail().setAttribute(JunkScore.JUNK_SCORE_ATTR, String.valueOf(score2.getCompleteStoredScores()));
             session.getMail().setAttribute(JunkScore.JUNK_SCORE_COMPOSED_ATTR, String.valueOf(composed.getCompleteStoredScores()));
         } else if (action.equals(REJECT_ACTION)) {
             if (maxScore <  composed.getCompleteStoredScores()) {
 
                 
                 String responseString = "554 "
                     + DSNStatus.getStatus(DSNStatus.PERMANENT,
                             DSNStatus.SECURITY_OTHER)
                     + " This message reach the spam hits treshold. Please contact the Postmaster if the email is not SPAM. Message rejected";
                 StringBuffer buffer = new StringBuffer(256).append(
                     "Rejected message from ").append(
                     session.getState().get(SMTPSession.SENDER)
                             .toString()).append(" from host ")
                     .append(session.getRemoteHost()).append(" (")
                     .append(session.getRemoteIPAddress()).append(
                             ") " + responseString).append(
                             ". Required rejection hits: "
                                     + maxScore
                                     + " hits: " + composed.getCompleteStoredScores());
                 getLogger().info(buffer.toString());
                 
                 session.writeResponse(responseString);
                 session.setStopHandlerProcessing(true);
                 session.abortMessage();
             }
         } else if (action.equals(HEADER_ACTION)) {
             try {
                 MimeMessage message = session.getMail().getMessage();
                 Map scores = composed.getStoredScores();
                 Iterator itScores = scores.keySet().iterator();
         
                 StringBuffer header = new StringBuffer();
                 while (itScores.hasNext()) {
                     String key = itScores.next().toString();
                     header.append(key);
                     header.append("=");
                     header.append(scores.get(key));
                     header.append("; ");
                 }
         
                 message.setHeader("X-JUNKSCORE", header.toString());
                 message.setHeader("X-JUNKSCORE-COMPOSED", String.valueOf(composed.getCompleteStoredScores()));
         
             } catch (MessagingException e) {
                 getLogger().info("Unable to add Junkscore to header: " + e.getMessage());
             }
         }
     }
         
     /**
      * @see org.apache.james.smtpserver.ConnectHandler#onConnect(org.apache.james.smtpserver.SMTPSession)
      */
     public void onConnect(SMTPSession session) {
         session.getState().put(JunkScore.JUNK_SCORE, new JunkScoreImpl());
         session.getConnectionState().put(JunkScore.JUNK_SCORE_SESSION, new JunkScoreImpl());
     } 
 }