/*
 * 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 net.sf.l2j.gameserver;

import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.Map;
import java.util.concurrent.ScheduledFuture;
import java.util.logging.Logger;

import javolution.util.FastList;
import javolution.util.FastMap;
import net.sf.l2j.Config;
import net.sf.l2j.gameserver.ai.CtrlEvent;
import net.sf.l2j.gameserver.instancemanager.DayNightSpawnManager;
import net.sf.l2j.gameserver.model.L2Character;

/**
 * This class ...
 *
 * @version $Revision: 1.1.4.8 $ $Date: 2005/04/06 16:13:24 $
 */
public class GameTimeController
{
	static final Logger _log = Logger.getLogger(GameTimeController.class.getName());

	public static final int TICKS_PER_SECOND = 10; // not able to change this without checking through code
	public static final int MILLIS_IN_TICK = 1000 / TICKS_PER_SECOND;

	private static GameTimeController _instance = new GameTimeController();

	protected static int _gameTicks;
	protected static long _gameStartTime;
	protected static boolean _isNight = false;

	private static Map<Integer,L2Character> _movingObjects = new FastMap<Integer,L2Character>().setShared(true);

	protected static TimerThread _timer;
	private ScheduledFuture<?> _timerWatcher;

	/**
	 * one ingame day is 240 real minutes
	 */
	public static GameTimeController getInstance()
	{
		return _instance;
	}

	private GameTimeController()
	{
		_gameStartTime = System.currentTimeMillis() - 3600000; // offset so that the server starts a day begin
		_gameTicks = 3600000 / MILLIS_IN_TICK; // offset so that the server starts a day begin

		_timer = new TimerThread();
		_timer.start();

		_timerWatcher = ThreadPoolManager.getInstance().scheduleGeneralAtFixedRate(new TimerWatcher(), 0, 1000);
        ThreadPoolManager.getInstance().scheduleGeneralAtFixedRate(new BroadcastSunState(), 0, 600000);

	}

	public boolean isNowNight()
	{
		return _isNight;
	}

	public int getGameTime()
	{
		return (_gameTicks / (TICKS_PER_SECOND * 10));
	}

	public static int getGameTicks()
	{
		return _gameTicks;
	}

	/**
	 * Add a L2Character to movingObjects of GameTimeController.<BR><BR>
	 *
	 * <B><U> Concept</U> :</B><BR><BR>
	 * All L2Character in movement are identified in <B>movingObjects</B> of GameTimeController.<BR><BR>
	 *
	 * @param cha The L2Character to add to movingObjects of GameTimeController
	 *
	 */
	public void registerMovingObject(L2Character cha)
	{
		if(cha == null) return;
		    if (!_movingObjects.containsKey(cha.getObjectId())) _movingObjects.put(cha.getObjectId(),cha);   
	}

	/**
	 * Move all L2Characters contained in movingObjects of GameTimeController.<BR><BR>
	 *
	 * <B><U> Concept</U> :</B><BR><BR>
	 * All L2Character in movement are identified in <B>movingObjects</B> of GameTimeController.<BR><BR>
	 *
	 * <B><U> Actions</U> :</B><BR><BR>
	 * <li>Update the position of each L2Character </li>
	 * <li>If movement is finished, the L2Character is removed from movingObjects </li>
	 * <li>Create a task to update the _knownObject and _knowPlayers of each L2Character that finished its movement and of their already known L2Object then notify AI with EVT_ARRIVED </li><BR><BR>
	 *
	 */
	protected void moveObjects()
	{
		// Create an FastList to contain all L2Character that are arrived to
		// destination
		FastList<L2Character> ended = null;
		
		// Go throw the table containing L2Character in movement
		for (L2Character ch : _movingObjects.values())
		{
			// If movement is finished, the L2Character is removed from
			// movingObjects and added to the ArrayList ended
			if (ch != null)
				if (ch.updatePosition(_gameTicks))
				{
					if (ended == null)
						ended = new FastList<L2Character>();
					
					ended.add(ch);
				}
		}
		if (ended != null)
		{
			_movingObjects.values().removeAll(ended);
			for (L2Character ch : ended)
				if (ch != null) // Disconnected?
					ThreadPoolManager.getInstance().executeTask(new MovingObjectArrived(ch));
			ended.clear();
		}
	}

	public void stopTimer()
	{
		_timerWatcher.cancel(true);
		_timer.interrupt();
	}

	class TimerThread extends Thread
	{
		protected Exception _error;

		public TimerThread()
		{
			super("GameTimeController");
			setDaemon(true);
			setPriority(MAX_PRIORITY);
			_error = null;
		}

		@Override
		public void run()
		{
			try
			{
				for (;;)
				{
					int _oldTicks=_gameTicks; // save old ticks value to avoid moving objects 2x in same tick
					long runtime = System.currentTimeMillis() - _gameStartTime; // from server boot to now

					_gameTicks = (int) (runtime / MILLIS_IN_TICK); // new ticks value (ticks now)

					if (_oldTicks != _gameTicks) moveObjects(); // XXX: if this makes objects go slower, remove it
					// but I think it can't make that effect. is it better to call moveObjects() twice in same
					// tick to make-up for missed tick ?   or is it better to ignore missed tick ?
					// (will happen very rarely but it will happen ... on garbage collection definitely)

					runtime = (System.currentTimeMillis() - _gameStartTime) - runtime;

					// calculate sleep time... time needed to next tick minus time it takes to call moveObjects()
					int sleepTime = 1 + MILLIS_IN_TICK - ((int) runtime) % MILLIS_IN_TICK;

					//_log.finest("TICK: "+_gameTicks);

					sleep(sleepTime); // hope other threads will have much more cpu time available now
					// SelectorThread most of all
				}
			}
			catch (Exception e)
			{
				_error = e;
			}
		}
	}

	class TimerWatcher implements Runnable
	{
		public void run()
		{
			if (!_timer.isAlive())
			{
				String time = (new SimpleDateFormat("HH:mm:ss")).format(new Date());
				_log.warning(time + " TimerThread stop with following error. restart it.");
				if (_timer._error != null) _timer._error.printStackTrace();

				_timer = new TimerThread();
				_timer.start();
			}
		}
	}

	/**
	 * Update the _knownObject and _knowPlayers of each L2Character that finished its movement and of their already known L2Object then notify AI with EVT_ARRIVED.<BR><BR>
	 */
	class MovingObjectArrived implements Runnable
    {
        private final L2Character _ended;
        
        MovingObjectArrived(L2Character ended)
        {
            _ended = ended;
        }
        
        public void run()
        {
            try
            {
            	if (_ended.hasAI()) // AI could be just disabled due to region turn off
            	{
            		if (Config.MOVE_BASED_KNOWNLIST) _ended.getKnownList().findObjects();
            		_ended.getAI().notifyEvent(CtrlEvent.EVT_ARRIVED);
            	}
            }
            catch (NullPointerException e)
            {
            	e.printStackTrace();
            }
        }
    }

	/**
	 * @param rise
	 */
	class BroadcastSunState implements Runnable
	{
		public void run()
		{
			int h = (getGameTime() / 60) % 24; // Time in hour
			boolean tempIsNight = (h < 6);

			if (tempIsNight != _isNight) { // If diff day/night state
                _isNight = tempIsNight; // Set current day/night varible to value of temp varible

                DayNightSpawnManager.getInstance().notifyChangeMode();
            }
		}
	}
}