@Override
	public boolean onBlockActivated(World worldIn, BlockPos pos, IBlockState state, EntityPlayer playerIn, EnumHand hand, @Nullable ItemStack heldItem, EnumFacing side, float hitX, float hitY, float hitZ)
	{
		if (worldIn.isRemote)
			return false;

		if (playerIn.getHeldItem(hand) == null)
		{
			IBlockState newState;
			switch(state.getValue(BlockBookcaseMulti.TYPE))
			{
			// 2/3 full
			case two3:
				newState = state.withProperty(TYPE, EnumBookshelf.two2);
				break;

			// 1/3 full
			case two2:
				newState = state.withProperty(TYPE, EnumBookshelf.one1);
				break;

			//Empty
			default:
				// Can't empty an empty bookcase
				return false;
			}

			worldIn.setBlockState(pos, newState);
			playerIn.inventory.addItemStackToInventory(new ItemStack(Items.BOOK));

			return true;
		}

		ItemStack book = new ItemStack(Items.BOOK);

		if (playerIn.getHeldItemMainhand() == book)
		{
			IBlockState newState;
			switch (state.getValue(BlockBookcaseMulti.TYPE))
			{
			case one1:
				newState = state.withProperty(TYPE, EnumBookshelf.two2);
				break;
			case two2:
				newState = state.withProperty(TYPE, EnumBookshelf.two3);
				break;
			case two3:
				newState = Blocks.BOOKSHELF.getDefaultState();
				break;
			default:
				// For completeness
				return false;
			}

			worldIn.setBlockState(pos, newState);
			--heldItem.stackSize;
			return true;
		}

		return true;
	}