LootUtils.java

/* Adds loot functions equivalent to the damage, stacksize and NBT of the
	 * input stack to the passed in array, if loot functions of the same type
	 * are not present. */
	public static LootFunction[] addStackFunctions(IItemStack iStack, LootFunction[] existingFunctions)
	{
		ItemStack stack = CraftTweakerMC.getItemStack(iStack);
		boolean sizeFuncExists = false, damageFuncExists = false, nbtFuncExists = false;
		for (LootFunction lootFunction : existingFunctions)
		{
			if (lootFunction instanceof SetCount) sizeFuncExists = true;
			if (lootFunction instanceof SetDamage || lootFunction instanceof SetMetadata) damageFuncExists = true;
			if (lootFunction instanceof SetNBT) nbtFuncExists = true;
		}
		int capacityRequired = existingFunctions.length + (sizeFuncExists ? 0 : 1) + (damageFuncExists ? 0 : 1)
				+ (nbtFuncExists ? 0 : 1);
		List<LootFunction> retList = Lists.newArrayListWithCapacity(capacityRequired);
		Collections.addAll(retList, existingFunctions);
		if (iStack.getAmount() > 1 && !sizeFuncExists)
		{
			retList.add(new SetCount(NO_CONDITIONS, new RandomValueRange(iStack.getAmount())));
		}
		if (iStack.getDamage() > 0 && !damageFuncExists)
		{
			if (stack.isItemStackDamageable())
			{
				// SetDamage takes a percentage, not a number
				retList.add(new SetDamage(NO_CONDITIONS,
						new RandomValueRange((float) stack.getItemDamage() / (float) stack.getMaxDamage())));
			}
			else
			{
				retList.add(new SetMetadata(NO_CONDITIONS, new RandomValueRange(iStack.getDamage())));
			}
		}
		IData stackData = iStack.getTag();
		if (stackData != DataMap.EMPTY && !nbtFuncExists)
		{
			retList.add(new SetNBT(NO_CONDITIONS, CraftTweakerMC.getNBTCompound(stackData)));
		}

		return retList.toArray(LootUtils.NO_FUNCTIONS);
	}