/*

  *   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.util.io;

 import java.io.BufferedOutputStream;

 import java.io.BufferedReader;

 import java.io.IOException;

 import java.io.InputStreamReader;

 import java.io.UnsupportedEncodingException;

 import java.net.Socket;

 import java.net.UnknownHostException;

 import org.sonews.storage.Article;

 /**

  * Posts an Article to a NNTP server using the POST command.

  * @author Christian Lins

  * @since sonews/0.5.0

  */

 public class ArticleWriter 

 {

   private BufferedOutputStream out;

   private BufferedReader       inr;

   public ArticleWriter(String host, int port)

     throws IOException, UnknownHostException

   {

     // Connect to NNTP server

     Socket socket = new Socket(host, port);

     this.out = new BufferedOutputStream(socket.getOutputStream());

     this.inr = new BufferedReader(new InputStreamReader(socket.getInputStream()));

     String line = inr.readLine();

     if(line == null || !line.startsWith("200 "))

     {

       throw new IOException("Invalid hello from server: " + line);

     }

   }

   public void close()

     throws IOException, UnsupportedEncodingException

   {

     this.out.write("QUIT\r\n".getBytes("UTF-8"));

     this.out.flush();

   }

   protected void finishPOST()

     throws IOException

   {

     this.out.write("\r\n.\r\n".getBytes());

     this.out.flush();

     String line = inr.readLine();

     if(line == null || !line.startsWith("240 ") || !line.startsWith("441 "))

     {

       throw new IOException(line);

     }

   }

   protected void preparePOST()

     throws IOException

   {

     this.out.write("POST\r\n".getBytes("UTF-8"));

     this.out.flush();

     String line = this.inr.readLine();

     if(line == null || !line.startsWith("340 "))

     {

       throw new IOException(line);

     }

   }

   public void writeArticle(Article article)

     throws IOException, UnsupportedEncodingException

   {

     byte[] buf = new byte[512];

     ArticleInputStream in = new ArticleInputStream(article);

     preparePOST();

     int len = in.read(buf);

     while(len != -1)

     {

       writeLine(buf, len);

       len = in.read(buf);

     }

     finishPOST();

   }

   /**

    * Writes the raw content of an article to the remote server. This method

    * does no charset conversion/handling of any kind so its the preferred

    * method for sending an article to remote peers.

    * @param rawArticle

    * @throws IOException

    */

   public void writeArticle(byte[] rawArticle)

     throws IOException

   {

     preparePOST();

     writeLine(rawArticle, rawArticle.length);

     finishPOST();

   }

   /**

    * Writes the given buffer to the connect remote server.

    * @param buffer

    * @param len

    * @throws IOException

    */

   protected void writeLine(byte[] buffer, int len)

     throws IOException

   {

     this.out.write(buffer, 0, len);

     this.out.flush();

   }

 }