/**
 * <p>
 * Copyright © 2009-2010, Bruce-Robert Pocock
 * </p>
 * <p>
 * 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.
 * </p>
 * <p>
 * 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.
 * </p>
 * <p>
 * You should have received a copy of the GNU General Public License
 * along with this program. If not, see <http://www.gnu.org/licenses/>.
 * </p>
 * 
 * @author brpocock
 */
package org.starhope.appius.game;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.net.Socket;
import java.util.Arrays;

import org.starhope.appius.except.PrivilegeRequiredException;
import org.starhope.appius.except.UserDeadException;
import org.starhope.appius.sys.op.OpCommands;
import org.starhope.appius.user.AbstractUser;
import org.starhope.appius.user.User;
import org.starhope.appius.util.AppiusConfig;

/**
 * Processing thread for an administrative connection (normally port
 * 2772)
 * 
 * @author brpocock
 * 
 */
public class AdminProcessor extends Thread {
	/**
	 * the maximum input line length accepted
	 */
	private static final int maxInputSize = 1024;
	/**
	 * the input stream
	 */
	private BufferedReader in;
	/**
	 * the output stream
	 */
	private PrintWriter out;

	/**
	 * the socket against which we're acting
	 */
	private final Socket socket;

	/**
	 * create a new administrative processing thread
	 * 
	 * @param userSocket the socket to which the remote user is
	 *            connected
	 */
	public AdminProcessor (final Socket userSocket) {
		socket = userSocket;
		setName ("adminprocessor"
				+ userSocket.getInetAddress ().toString ());
	}

	/**
	 * @return accept input from the admin
	 */
	private String grabInput () {
		final StringBuilder inputBuilder = new StringBuilder ();
		while (true) {
			try {
				int chr = -1;
				if (in.ready ()) {
					try {
						chr = in.read ();
					} catch (final java.net.SocketException e) {
						chr = -1;
					}
					if ('\0' == chr || '\n' == chr || '\r' == chr) {
						break;
					}
					if (chr == -1) {
						socket.close ();
						return null;
					}
					inputBuilder.append ((char) chr);
					if (inputBuilder.length () > AdminProcessor.maxInputSize) {
						break;
					}
				} else { // no input pending
					try {
						Thread.sleep (AppiusConfig.getIntOrDefault (
								"org.starhope.appius.ioDelay", 100));
					} catch (final InterruptedException e) {
						// no problem, keep going
					}
				}
			} catch (final IOException e) {
				AppiusClaudiusCaecus.reportBug (e);
				return null;
			}
		}

		return inputBuilder.toString ();
	}

	/**
	 * @param inputLine the input from the client
	 * @return output line to return to the client, or “null” to
	 *         disconnect
	 * @throws PrivilegeRequiredException if the client doesn't specify
	 *             the name of a Developer-level user
	 */
	private String processInput (final String inputLine)
		throws PrivilegeRequiredException {
		final String [] words = inputLine.split (" ");
		final AbstractUser who = User.getByLogin (words [1]);
		who.assertStaffLevel (User.STAFF_LEVEL_DEVELOPER);
		if ("dumpthreads".equals (words [0])) {
			OpCommands.op_dumpthreads (words, who, AppiusClaudiusCaecus
					.getZone ("$Eden").getNextLobby ());
			return "OK\n";
		}
		if ("wallzones".equals (words [0])) {
			final String [] wall = Arrays.copyOfRange (words, 2,
					words.length);
			OpCommands.op_wallzones (wall, who, AppiusClaudiusCaecus
					.getZone ("$Eden").getNextLobby ());
			return "OK\n";
		}
		if ("reloadconfig".equals (words [0])) {
			OpCommands.op_reloadconfig (words, who,
					AppiusClaudiusCaecus.getZone ("$Eden")
							.getNextLobby ());
			return "OK\n";
		}
		if ("kick".equals (words [0])) {
			OpCommands.op_kick (new String [] { words [2], words [3],
					words [4] }, who, AppiusClaudiusCaecus.getZone (
					"$Eden").getNextLobby ());
			return "OK\n";
		}
		return "No\n";
	}

	/**
	 * This is an overriding method.
	 * 
	 * @see java.lang.Thread#run()
	 */
	@Override
	public void run () {
		/*
		 * Setup stanza
		 */

		try {
			setup ();

			/*
			 * Main I/O loop
			 */

			while (true) {
				/*
				 * Gather input line
				 */
				final String inputLine = grabInput ();

				String outputLine = null;
				try {
					outputLine = processInput (inputLine);
				} catch (final Throwable th) {
					out.print ("Error\t" + th.getMessage () + "\n");
				}

				/*
				 * If the output is null pointer, we're done
				 */
				if (null == outputLine) {
					out.close ();
					in.close ();
					if (null != socket) {
						socket.close ();
					}
					return; // End of thread.
				}
				/*
				 * If the output is empty, don't send anything.
				 */
				if ( ! ("".equals (outputLine) || "\0"
						.equals (outputLine))) {
					out.print (outputLine);
				}
			}

		} catch (final IOException e) {
			AppiusClaudiusCaecus.reportBug (e);
		} catch (final Throwable e) {
			AppiusClaudiusCaecus.reportBug (e);
		} finally {
			out.close ();
			if (null != socket) {
				try {
					socket.close ();
				} catch (final IOException e) {
					AppiusClaudiusCaecus.reportBug (e);
				}
			}
		}
		// End of thread.
	}

	/**
	 * Set up this thread to execute
	 * 
	 * @throws IOException if the I/O streams can't be initialized
	 * @throws UserDeadException if the user disconnects before setup is
	 *             complete
	 */
	private void setup () throws IOException, UserDeadException {
		out = new PrintWriter (socket.getOutputStream (), true);
		in = new BufferedReader (new InputStreamReader (socket
				.getInputStream ()));

	}
}