/*

  *   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.acl;

 import java.io.IOException;

 import java.util.Arrays;

 import java.util.logging.Level;

 import java.util.logging.Logger;

 import java.util.regex.Matcher;

 import java.util.regex.Pattern;

 import org.sonews.daemon.NNTPConnection;

 import org.sonews.daemon.command.Command;

 import org.sonews.storage.StorageBackendException;

 import org.sonews.storage.StorageManager;

 /**

  *

  * @author František Kučera (frantovo.cz)

  */

 public class AuthInfoCommand implements Command {

 	private static final Logger log = Logger.getLogger(AuthInfoCommand.class.getName());

 	private static String[] SUPPORTED_COMMANDS = {"AUTHINFO"};

 	@Override

 	public boolean hasFinished() {

 		return true;

 	}

 	@Override

 	public String impliedCapability() {

 		return "AUTHINFO";

 	}

 	@Override

 	public boolean isStateful() {

 		// TODO: make it statefull?

 		return false;

 	}

 	@Override

 	public String[] getSupportedCommandStrings() {

 		return SUPPORTED_COMMANDS;

 	}

 	@Override

 	public void processLine(NNTPConnection conn, String line, byte[] rawLine) throws IOException, StorageBackendException {

 		Pattern commandPattern = Pattern.compile("AUTHINFO (USER|PASS) (.*)", Pattern.CASE_INSENSITIVE);

 		Matcher commandMatcher = commandPattern.matcher(line);

 		if (commandMatcher.matches()) {

 			if (conn.getUser() != null && conn.getUser().isAuthenticated()) {

 				conn.println("502 Command unavailable (you are already authenticated)");

 			} else if ("USER".equalsIgnoreCase(commandMatcher.group(1))) {

 				conn.setUser(new User(commandMatcher.group(2)));

 				conn.println("381 Password required"); // ask user for his password

 				log.log(Level.FINE, "User ''{0}'' greets us. We are waiting for his password.", conn.getUser().getUserName());

 			} else if ("PASS".equalsIgnoreCase(commandMatcher.group(1))) {

 				if (conn.getUser() == null) {

 					conn.println("482 Authentication commands issued out of sequence");

 				} else {

 					char[] password = commandMatcher.group(2).toCharArray();

 					// TODO: StorageManager should return User object instead of boolean (so there could be transferred some additional information about user)

 					boolean goodPassword = StorageManager.current().authenticateUser(conn.getUser().getUserName(), password);

 					Arrays.fill(password, '*');

 					commandMatcher = null;

 					if (goodPassword) {

 						conn.println("281 Authentication accepted");

 						conn.getUser().setAuthenticated(true);

 						log.log(Level.INFO, "User ''{0}'' has been succesfully authenticated.", conn.getUser().getUserName());

 					} else {

 						log.log(Level.INFO, "User ''{0}'' has provided wrong password.", conn.getUser().getUserName());

 						conn.setUser(null);

 						conn.println("481 Authentication failed: wrong password");

 					}

 				}

 			} else {

 				// impossible, see commandPattern

 				conn.println("500 Unknown command");

 			}

 		} else {

 			conn.println("500 Unknown command, expecting AUTHINFO USER username or AUTHINFO PASS password ");

 		}

 	}

 }