item handler code insertItem

aitemhandler.java

@Override
	public ItemStack insertItem(int slot, ItemStack stack, boolean simulate) 
	{
		if (count == 0)
		{
			this.barrelContents[0]=stack;
			count = stack.stackSize;
		}
		if (count == size)
		{
			//barrel is full
			return stack;
		}
		if (this.barrelContents[0].isItemEqual(stack))
		{
			if (stack.stackSize+count<=size)
			{
				//input stack will not fill barrel
				count+=stack.stackSize;
				return null;
			} else if (stack.stackSize+count>size)
			{
				//input stack will fill barrel
				int a = size - count;
				count = size;
				stack.stackSize -= a;
				return stack;
			
			}
		}
		return stack;
	}