/*
 * 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 com.l2jserver.gameserver.handler;

import java.util.HashMap;
import java.util.Map;

import com.l2jserver.gameserver.model.items.L2EtcItem;

/**
 * This class manages handlers of items
 * @author UnAfraid
 */
public class ItemHandler implements IHandler<IItemHandler, L2EtcItem>
{
	private final Map<String, IItemHandler> _datatable;
	
	/**
	 * Constructor of ItemHandler
	 */
	protected ItemHandler()
	{
		_datatable = new HashMap<>();
	}
	
	/**
	 * Adds handler of item type in <I>datatable</I>.<BR>
	 * <BR>
	 * <B><I>Concept :</I></U><BR>
	 * This handler is put in <I>datatable</I> Map &lt;String ; IItemHandler &gt; for each ID corresponding to an item type (existing in classes of package itemhandlers) sets as key of the Map.
	 * @param handler (IItemHandler)
	 */
	@Override
	public void registerHandler(IItemHandler handler)
	{
		_datatable.put(handler.getClass().getSimpleName(), handler);
	}
	
	@Override
	public synchronized void removeHandler(IItemHandler handler)
	{
		_datatable.remove(handler.getClass().getSimpleName());
	}
	
	/**
	 * Returns the handler of the item
	 * @param item
	 * @return IItemHandler
	 */
	@Override
	public IItemHandler getHandler(L2EtcItem item)
	{
		if ((item == null) || (item.getHandlerName() == null))
		{
			return null;
		}
		return _datatable.get(item.getHandlerName());
	}
	
	/**
	 * Returns the number of elements contained in datatable
	 * @return int : Size of the datatable
	 */
	@Override
	public int size()
	{
		return _datatable.size();
	}
	
	/**
	 * Create ItemHandler if doesn't exist and returns ItemHandler
	 * @return ItemHandler
	 */
	public static ItemHandler getInstance()
	{
		return SingletonHolder._instance;
	}
	
	private static class SingletonHolder
	{
		protected static final ItemHandler _instance = new ItemHandler();
	}
}