Applied-Energistics-2-tilera-Edition/src/api/java/mekanism/common/util/StackUtils.java

package mekanism.common.util;

import java.util.ArrayList;
import java.util.List;

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

public final class StackUtils
{
	public static List<ItemStack> split(ItemStack stack)
	{
		if(stack == null || stack.stackSize == 0)
		{
			return null;
		}

		List<ItemStack> ret = new ArrayList<ItemStack>();

		if(stack.stackSize == 1)
		{
			ret.add(stack);
			return ret;
		}

		int remain = stack.stackSize % 2;
		int split = (int)((float)(stack.stackSize)/2F);

		ret.add(size(stack, split+remain));
		ret.add(size(stack, split));

		return ret;
	}

	public static Item getItem(ItemStack stack)
	{
		if(stack == null)
		{
			return null;
		}

		return stack.getItem();
	}

	public static boolean diffIgnoreNull(ItemStack stack1, ItemStack stack2)
	{
		if(stack1 == null || stack2 == null)
		{
			return false;
		}

		return stack1.getItem() != stack2.getItem() || stack1.getItemDamage() != stack2.getItemDamage();
	}

	public static boolean equalsWildcard(ItemStack wild, ItemStack check)
	{
		return wild.getItem() == check.getItem() && (wild.getItemDamage() == OreDictionary.WILDCARD_VALUE || wild.getItemDamage() == check.getItemDamage());
	}

	public static List<ItemStack> even(ItemStack stack1, ItemStack stack2)
	{
		ArrayList<ItemStack> ret = new ArrayList<ItemStack>();

		if(getSize(stack1) == getSize(stack2) || Math.abs(getSize(stack1)-getSize(stack2)) == 1)
		{
			ret.add(stack1);
			ret.add(stack2);

			return ret;
		}

		if(getSize(stack1) > getSize(stack2))
		{
			int diff = getSize(stack1)-getSize(stack2);

			List<ItemStack> split = split(size(stack1, diff));

			ret.add(subtract(stack1, split.get(0)));
			ret.add(add(stack2, split.get(0)));
		}
		else if(getSize(stack2) > getSize(stack1))
		{
			int diff = getSize(stack2)-getSize(stack1);

			List<ItemStack> split = split(size(stack2, diff));

			ret.add(subtract(stack2, split.get(0)));
			ret.add(add(stack1, split.get(0)));
		}

		return ret;
	}

	public static ItemStack add(ItemStack stack1, ItemStack stack2)
	{
		if(stack1 == null)
		{
			return stack2;
		}
		else if(stack2 == null)
		{
			return stack1;
		}

		return size(stack1, getSize(stack1)+getSize(stack2));
	}

	public static ItemStack subtract(ItemStack stack1, ItemStack stack2)
	{
		if(stack1 == null)
		{
			return null;
		}
		else if(stack2 == null)
		{
			return stack1;
		}

		return size(stack1, getSize(stack1)-getSize(stack2));
	}

	public static ItemStack size(ItemStack stack, int size)
	{
		if(size <= 0 || stack == null)
		{
			return null;
		}

		ItemStack ret = stack.copy();
		ret.stackSize = size;
		return ret;
	}

	public static ItemStack copy(ItemStack stack)
	{
		if(stack == null)
		{
			return null;
		}

		return stack.copy();
	}

	public static int getSize(ItemStack stack)
	{
		return stack != null ? stack.stackSize : 0;
	}
}