/*
 * 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.recipes;


import java.util.Arrays;
import java.util.LinkedList;
import java.util.List;

import com.google.common.base.Preconditions;

import net.minecraft.item.ItemStack;
import net.minecraftforge.oredict.OreDictionary;

import appeng.api.exceptions.MissingIngredientError;
import appeng.api.exceptions.RecipeError;
import appeng.api.exceptions.RegistrationError;
import appeng.api.recipes.IIngredient;


public class GroupIngredient implements IIngredient
{

	private final String name;
	private final List<IIngredient> ingredients;
	private final int qty;
	private ItemStack[] baked;
	private boolean isInside = false;

	public GroupIngredient( final String myName, final List<IIngredient> ingredients, final int qty ) throws RecipeError
	{
		Preconditions.checkNotNull( myName );
		Preconditions.checkNotNull( ingredients );
		Preconditions.checkState( !ingredients.isEmpty() );
		Preconditions.checkState( qty > 0 );

		this.name = myName;
		this.qty = qty;

		for( final IIngredient ingredient : ingredients )
		{
			if( ingredient.isAir() )
			{
				throw new RecipeError( "Cannot include air in a group." );
			}
		}

		this.ingredients = ingredients;
	}

	IIngredient copy( final int qty ) throws RecipeError
	{
		Preconditions.checkState( qty > 0 );
		return new GroupIngredient( this.name, this.ingredients, qty );
	}

	@Override
	public ItemStack getItemStack() throws RegistrationError, MissingIngredientError
	{
		throw new RegistrationError( "Cannot pass group of items to a recipe which desires a single recipe item." );
	}

	@Override
	public ItemStack[] getItemStackSet() throws RegistrationError, MissingIngredientError
	{
		if( this.baked != null )
		{
			return this.baked;
		}

		if( this.isInside )
		{
			return new ItemStack[0];
		}

		final List<ItemStack> out = new LinkedList<ItemStack>();
		this.isInside = true;
		try
		{
			for( final IIngredient i : this.ingredients )
			{
				try
				{
					out.addAll( Arrays.asList( i.getItemStackSet() ) );
				}
				catch( final MissingIngredientError mir )
				{
					// oh well this is a group!
				}
			}
		}
		finally
		{
			this.isInside = false;
		}

		if( out.isEmpty() )
		{
			throw new MissingIngredientError( this.toString() + " - group could not be resolved to any items." );
		}

		for( final ItemStack is : out )
		{
			is.stackSize = this.qty;
		}

		return out.toArray( new ItemStack[out.size()] );
	}

	@Override
	public boolean isAir()
	{
		return false;
	}

	@Override
	public String getNameSpace()
	{
		return "";
	}

	@Override
	public String getItemName()
	{
		return this.name;
	}

	@Override
	public int getDamageValue()
	{
		return OreDictionary.WILDCARD_VALUE;
	}

	@Override
	public int getQty()
	{
		return this.qty;
	}

	@Override
	public void bake() throws RegistrationError, MissingIngredientError
	{
		this.baked = null;
		this.baked = this.getItemStackSet();
	}
}