/*
 * This file is part of Applied Energistics 2.
 * Copyright (c) 2013 - 2014, AlgorithmX2, All rights reserved.
 *
 * Applied Energistics 2 is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Lesser General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * Applied Energistics 2 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 Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with Applied Energistics 2.  If not, see <http://www.gnu.org/licenses/lgpl>.
 */

package appeng.util.item;


import java.util.Collection;

import appeng.api.AEApi;
import appeng.api.config.FuzzyMode;
import appeng.api.storage.data.IAEItemStack;
import appeng.api.storage.data.IItemContainer;


public class ItemModList implements IItemContainer<IAEItemStack>
{

	private final IItemContainer<IAEItemStack> backingStore;
	private final IItemContainer<IAEItemStack> overrides = AEApi.instance().storage().createItemList();

	public ItemModList( final IItemContainer<IAEItemStack> backend )
	{
		this.backingStore = backend;
	}

	@Override
	public void add( final IAEItemStack option )
	{
		IAEItemStack over = this.overrides.findPrecise( option );
		if( over == null )
		{
			over = this.backingStore.findPrecise( option );
			if( over == null )
			{
				this.overrides.add( option );
			}
			else
			{
				option.add( over );
				this.overrides.add( option );
			}
		}
		else
		{
			this.overrides.add( option );
		}
	}

	@Override
	public IAEItemStack findPrecise( final IAEItemStack i )
	{
		final IAEItemStack over = this.overrides.findPrecise( i );
		if( over == null )
		{
			return this.backingStore.findPrecise( i );
		}
		return over;
	}

	@Override
	public Collection<IAEItemStack> findFuzzy( final IAEItemStack input, final FuzzyMode fuzzy )
	{
		return this.overrides.findFuzzy( input, fuzzy );
	}

	@Override
	public boolean isEmpty()
	{
		return this.overrides.isEmpty() && this.backingStore.isEmpty();
	}
}