onItemUse

public EnumActionResult onItemUse(EntityPlayer player, World worldIn, BlockPos pos, EnumHand hand, EnumFacing facing, float hitX, float hitY, float hitZ)
    {
        ItemStack itemstack = player.getHeldItem(hand);

        if (!itemstack.isEmpty() && player.canPlayerEdit(pos, facing, itemstack))
        {
            IBlockState iblockstate = worldIn.getBlockState(pos);
            Block block = iblockstate.getBlock();
            BlockPos blockpos = pos;

            if ((facing != EnumFacing.UP || block != this.block) && !block.isReplaceable(worldIn, pos))
            {
                blockpos = pos.offset(facing);
                iblockstate = worldIn.getBlockState(blockpos);
                block = iblockstate.getBlock();
            }

            if (block == this.block)
            {
                int i = ((Integer)iblockstate.getValue(BlockSnow.LAYERS)).intValue();

                if (i < 8)
                {
                    IBlockState iblockstate1 = iblockstate.withProperty(BlockSnow.LAYERS, Integer.valueOf(i + 1));
                    AxisAlignedBB axisalignedbb = iblockstate1.getCollisionBoundingBox(worldIn, blockpos);

                    if (axisalignedbb != Block.NULL_AABB && worldIn.checkNoEntityCollision(axisalignedbb.offset(blockpos)) && worldIn.setBlockState(blockpos, iblockstate1, 10))
                    {
                        SoundType soundtype = this.block.getSoundType(iblockstate1, worldIn, pos, player);
                        worldIn.playSound(player, blockpos, soundtype.getPlaceSound(), SoundCategory.BLOCKS, (soundtype.getVolume() + 1.0F) / 2.0F, soundtype.getPitch() * 0.8F);

                        if (player instanceof EntityPlayerMP)
                        {
                            CriteriaTriggers.PLACED_BLOCK.trigger((EntityPlayerMP)player, pos, itemstack);
                        }

                        itemstack.shrink(1);
                        return EnumActionResult.SUCCESS;
                    }
                }
            }

            return super.onItemUse(player, worldIn, pos, hand, facing, hitX, hitY, hitZ);
        }
        else
        {
            return EnumActionResult.FAIL;
        }
    }