/*

  *   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.io.BufferedOutputStream;

 import java.io.BufferedReader;

 import java.io.IOException;

 import java.io.InputStreamReader;

 import java.net.Socket;

 import java.net.UnknownHostException;

 import org.sonews.config.Config;

 import org.sonews.storage.Article;

 import org.sonews.util.io.ArticleInputStream;

 /**

  * Connects to a SMTP server and sends a given Article to it.

  * @author Christian Lins

  * @since sonews/1.0

  */

 class SMTPTransport

 {

   protected BufferedReader       in;

   protected BufferedOutputStream out;

   protected Socket               socket;

   public SMTPTransport(String host, int port)

     throws IOException, UnknownHostException

   {

     socket = new Socket(host, port);

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

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

     // Read helo from server

     String line = this.in.readLine();

     if(line == null || !line.startsWith("220 "))

     {

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

     }

     // Send HELO to server

     this.out.write(

       ("HELO " + Config.inst().get(Config.HOSTNAME, "localhost") + "\r\n").getBytes("UTF-8"));

     this.out.flush();

     line = this.in.readLine();

     if(line == null || !line.startsWith("250 "))

     {

       throw new IOException("Unexpected reply: " + line);

     }

   }

   public SMTPTransport(String host)

     throws IOException

   {

     this(host, 25);

   }

   public void close()

     throws IOException

   {

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

     this.out.flush();

     this.in.readLine();

     this.socket.close();

   }

   public void send(Article article, String mailFrom, String rcptTo)

     throws IOException

   {

     assert(article != null);

     assert(mailFrom != null);

     assert(rcptTo != null);

     this.out.write(("MAIL FROM: " + mailFrom).getBytes("UTF-8"));

     this.out.flush();

     String line = this.in.readLine();

     if(line == null || !line.startsWith("250 "))

     {

       throw new IOException("Unexpected reply: " + line);

     }

     this.out.write(("RCPT TO: " + rcptTo).getBytes("UTF-8"));

     this.out.flush();

     line  = this.in.readLine();

     if(line == null || !line.startsWith("250 "))

     {

       throw new IOException("Unexpected reply: " + line);

     }

     this.out.write("DATA".getBytes("UTF-8"));

     this.out.flush();

     line = this.in.readLine();

     if(line == null || !line.startsWith("354 "))

     {

       throw new IOException("Unexpected reply: " + line);

     }

     ArticleInputStream   artStream = new ArticleInputStream(article);

     for(int b = artStream.read(); b >= 0; b = artStream.read())

     {

       this.out.write(b);

     }

     // Flush the binary stream; important because otherwise the output

     // will be mixed with the PrintWriter.

     this.out.flush();

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

     this.out.flush();

     line = this.in.readLine();

     if(line == null || !line.startsWith("250 "))

     {

       throw new IOException("Unexpected reply: " + line);

     }

   }

 }