1.1 --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
     1.2 +++ b/src/org/sonews/daemon/command/NextPrevCommand.java	Sun Aug 29 17:28:58 2010 +0200
     1.3 @@ -0,0 +1,116 @@
     1.4 +/*
     1.5 + *   SONEWS News Server
     1.6 + *   see AUTHORS for the list of contributors
     1.7 + *
     1.8 + *   This program is free software: you can redistribute it and/or modify
     1.9 + *   it under the terms of the GNU General Public License as published by
    1.10 + *   the Free Software Foundation, either version 3 of the License, or
    1.11 + *   (at your option) any later version.
    1.12 + *
    1.13 + *   This program is distributed in the hope that it will be useful,
    1.14 + *   but WITHOUT ANY WARRANTY; without even the implied warranty of
    1.15 + *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    1.16 + *   GNU General Public License for more details.
    1.17 + *
    1.18 + *   You should have received a copy of the GNU General Public License
    1.19 + *   along with this program.  If not, see <http://www.gnu.org/licenses/>.
    1.20 + */
    1.21 +
    1.22 +package org.sonews.daemon.command;
    1.23 +
    1.24 +import java.io.IOException;
    1.25 +import org.sonews.daemon.NNTPConnection;
    1.26 +import org.sonews.storage.Article;
    1.27 +import org.sonews.storage.Channel;
    1.28 +import org.sonews.storage.StorageBackendException;
    1.29 +
    1.30 +/**
    1.31 + * Class handling the NEXT and LAST command.
    1.32 + * @author Christian Lins
    1.33 + * @author Dennis Schwerdel
    1.34 + * @since n3tpd/0.1
    1.35 + */
    1.36 +public class NextPrevCommand implements Command
    1.37 +{
    1.38 +
    1.39 +  @Override
    1.40 +  public String[] getSupportedCommandStrings()
    1.41 +  {
    1.42 +    return new String[]{"NEXT", "PREV"};
    1.43 +  }
    1.44 +
    1.45 +  @Override
    1.46 +  public boolean hasFinished()
    1.47 +  {
    1.48 +    return true;
    1.49 +  }
    1.50 +
    1.51 +  @Override
    1.52 +  public String impliedCapability()
    1.53 +  {
    1.54 +    return null;
    1.55 +  }
    1.56 +
    1.57 +  @Override
    1.58 +  public boolean isStateful()
    1.59 +  {
    1.60 +    return false;
    1.61 +  }
    1.62 +
    1.63 +  @Override
    1.64 +  public void processLine(NNTPConnection conn, final String line, byte[] raw)
    1.65 +    throws IOException, StorageBackendException
    1.66 +  {
    1.67 +    final Article currA = conn.getCurrentArticle();
    1.68 +    final Channel currG = conn.getCurrentChannel();
    1.69 +    
    1.70 +    if (currA == null)
    1.71 +    {
    1.72 +      conn.println("420 no current article has been selected");
    1.73 +      return;
    1.74 +    }
    1.75 +    
    1.76 +    if (currG == null)
    1.77 +    {
    1.78 +      conn.println("412 no newsgroup selected");
    1.79 +      return;
    1.80 +    }
    1.81 +    
    1.82 +    final String[] command = line.split(" ");
    1.83 +
    1.84 +    if(command[0].equalsIgnoreCase("NEXT"))
    1.85 +    {
    1.86 +      selectNewArticle(conn, currA, currG, 1);
    1.87 +    }
    1.88 +    else if(command[0].equalsIgnoreCase("PREV"))
    1.89 +    {
    1.90 +      selectNewArticle(conn, currA, currG, -1);
    1.91 +    }
    1.92 +    else
    1.93 +    {
    1.94 +      conn.println("500 internal server error");
    1.95 +    }
    1.96 +  }
    1.97 +  
    1.98 +  private void selectNewArticle(NNTPConnection conn, Article article, Channel grp,
    1.99 +    final int delta)
   1.100 +    throws IOException, StorageBackendException
   1.101 +  {
   1.102 +    assert article != null;
   1.103 +
   1.104 +    article = grp.getArticle(grp.getIndexOf(article) + delta);
   1.105 +
   1.106 +    if(article == null)
   1.107 +    {
   1.108 +      conn.println("421 no next article in this group");
   1.109 +    }
   1.110 +    else
   1.111 +    {
   1.112 +      conn.setCurrentArticle(article);
   1.113 +      conn.println("223 " + conn.getCurrentChannel().getIndexOf(article)
   1.114 +                    + " " + article.getMessageID()
   1.115 +                    + " article retrieved - request text separately");
   1.116 +    }
   1.117 +  }
   1.118 +
   1.119 +}