/*

 *   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.daemon.command;

import java.io.IOException;

import org.sonews.storage.Article;

import org.sonews.daemon.NNTPConnection;

import org.sonews.storage.Group;

import org.sonews.storage.StorageBackendException;

/**

 * Class handling the ARTICLE, BODY and HEAD commands.

 * @author Christian Lins

 * @author Dennis Schwerdel

 * @since n3tpd/0.1

 */

public class ArticleCommand implements Command {

	@Override

	public String[] getSupportedCommandStrings() {

		return new String[]{"ARTICLE", "BODY", "HEAD"};

	}

	@Override

	public boolean hasFinished() {

		return true;

	}

	@Override

	public String impliedCapability() {

		return null;

	}

	@Override

	public boolean isStateful() {

		return false;

	}

	// TODO: Refactor this method to reduce its complexity!

	@Override

	public void processLine(NNTPConnection conn, final String line, byte[] raw)

			throws IOException {

		final String[] command = line.split(" ");

		Article article = null;

		long artIndex = -1;

		if (command.length == 1) {

			article = conn.getCurrentArticle();

			if (article == null) {

				conn.println("420 no current article has been selected");

				return;

			}

		} else if (command[1].matches(NNTPConnection.MESSAGE_ID_PATTERN)) {

			// Message-ID

			article = Article.getByMessageID(command[1]);

			if (article == null) {

				conn.println("430 no such article found");

				return;

			}

		} else {

			// Message Number

			try {

				Group currentGroup = conn.getCurrentChannel();

				if (currentGroup == null) {

					conn.println("400 no group selected");

					return;

				}

				artIndex = Long.parseLong(command[1]);

				article = currentGroup.getArticle(artIndex);

			} catch (NumberFormatException ex) {

				ex.printStackTrace();

			} catch (StorageBackendException ex) {

				ex.printStackTrace();

			}

			if (article == null) {

				conn.println("423 no such article number in this group");

				return;

			}

			conn.setCurrentArticle(article);

		}

		if (command[0].equalsIgnoreCase("ARTICLE")) {

			conn.println("220 " + artIndex + " " + article.getMessageID()

					+ " article retrieved - head and body follow");

			conn.println(article.getHeaderSource());

			conn.println("");

			conn.println(article.getBody());

			conn.println(".");

		} else if (command[0].equalsIgnoreCase("BODY")) {

			conn.println("222 " + artIndex + " " + article.getMessageID() + " body");

			conn.println(article.getBody());

			conn.println(".");

		} /*

		 * HEAD: This command is mandatory.

		 *

		 * Syntax

		 *    HEAD message-id

		 *    HEAD number

		 *    HEAD

		 *

		 * Responses

		 *

		 * First form (message-id specified)

		 *  221 0|n message-id    Headers follow (multi-line)

		 *  430                   No article with that message-id

		 *

		 * Second form (article number specified)

		 *  221 n message-id      Headers follow (multi-line)

		 *  412                   No newsgroup selected

		 *  423                   No article with that number

		 *

		 * Third form (current article number used)

		 *  221 n message-id      Headers follow (multi-line)

		 *  412                   No newsgroup selected

		 *  420                   Current article number is invalid

		 *

		 * Parameters

		 *  number        Requested article number

		 *  n             Returned article number

		 *  message-id    Article message-id

		 */ else if (command[0].equalsIgnoreCase("HEAD")) {

			conn.println("221 " + artIndex + " " + article.getMessageID()

					+ " Headers follow (multi-line)");

			conn.println(article.getHeaderSource());

			conn.println(".");

		}

	}

}