/*

  *   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();

 	}

 }