/*

  *   SONEWS News Server

  *   see AUTHORS for the list of contributors

  *

  *   This program is free software: you can redistribute it and/or modify

  *   it under the terms of the GNU General Public License as published by

  *   the Free Software Foundation, either version 3 of the License, or

  *   (at your option) any later version.

  *

  *   This program is distributed in the hope that it will be useful,

  *   but WITHOUT ANY WARRANTY; without even the implied warranty of

  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

  *   GNU General Public License for more details.

  *

  *   You should have received a copy of the GNU General Public License

  *   along with this program.  If not, see <http://www.gnu.org/licenses/>.

  */

 package org.sonews.mlgw;

 import java.util.Properties;

 import javax.mail.AuthenticationFailedException;

 import javax.mail.Authenticator;

 import javax.mail.Flags.Flag;

 import javax.mail.Folder;

 import javax.mail.Message;

 import javax.mail.MessagingException;

 import javax.mail.NoSuchProviderException;

 import javax.mail.PasswordAuthentication;

 import javax.mail.Session;

 import javax.mail.Store;

 import org.sonews.daemon.Config;

 import org.sonews.daemon.AbstractDaemon;

 import org.sonews.util.Log;

 import org.sonews.util.Stats;

 /**

  * Daemon polling for new mails in a POP3 account to be delivered to newsgroups.

  * @author Christian Lins

  * @since sonews/0.5.0

  */

 public class MailPoller extends AbstractDaemon

 {

   static class PasswordAuthenticator extends Authenticator

   {

     @Override

     public PasswordAuthentication getPasswordAuthentication()

     {

       final String username = 

         Config.getInstance().get(Config.MLPOLL_USER, "user");

       final String password = 

         Config.getInstance().get(Config.MLPOLL_PASSWORD, "mysecret");

       return new PasswordAuthentication(username, password);

     }

   }

   @Override

   public void run()

   {

     Log.msg("Starting Mailinglist Poller...", false);

     int errors = 0;

     while(isRunning() && errors < 5)

     {

       try

       {

         // Wait some time between runs. At the beginning has advantages,

         // because the wait is not skipped if an exception occurs.

         Thread.sleep(60000 * (errors + 1)); // one minute * errors

         final String host     = 

           Config.getInstance().get(Config.MLPOLL_HOST, "samplehost");

         final String username = 

           Config.getInstance().get(Config.MLPOLL_USER, "user");

         final String password = 

           Config.getInstance().get(Config.MLPOLL_PASSWORD, "mysecret");

         Stats.getInstance().mlgwRunStart();

         // Create empty properties

         Properties props = System.getProperties();

         props.put("mail.pop3.host", host);

         // Get session

         Session session = Session.getInstance(props);

         // Get the store

         Store store = session.getStore("pop3");

         store.connect(host, 110, username, password);

         // Get folder

         Folder folder = store.getFolder("INBOX");

         folder.open(Folder.READ_WRITE);

         // Get directory

         Message[] messages = folder.getMessages();

         // Dispatch messages and delete it afterwards on the inbox

         for(Message message : messages)

         {

           String subject = message.getSubject();

           System.out.println("MLGateway: message with subject \"" + subject + "\" received.");

           if(Dispatcher.toGroup(message)

             || Config.getInstance().get(Config.MLPOLL_DELETEUNKNOWN, false))

           {

             // Delete the message

             message.setFlag(Flag.DELETED, true);

           }

         }

         // Close connection 

         folder.close(true); // true to expunge deleted messages

         store.close();

         errors = 0;

         Stats.getInstance().mlgwRunEnd();

       }

       catch(NoSuchProviderException ex)

       {

         Log.msg(ex.toString(), false);

         shutdown();

       }

       catch(AuthenticationFailedException ex)

       {

         // AuthentificationFailedException may be thrown if credentials are

         // bad or if the Mailbox is in use (locked).

         ex.printStackTrace();

         errors++;

       }

       catch(InterruptedException ex)

       {

         System.out.println("sonews: " + this + " returns.");

         return;

       }

       catch(MessagingException ex)

       {

         ex.printStackTrace();

         errors++;

       }

       catch(Exception ex)

       {

         ex.printStackTrace();

         errors++;

       }

     }

     Log.msg("MailPoller exited.", false);

   }

 }