No sitting when no air above chair

[Bastrabun]

Could you make it that players cannot sit down on a chair when there is no air node above? If they do so, their head will be inside the node enabling them to xray the wall.

Untested:

if minetest.get_node({x=pos.x, y=pos.y+1, z=pos.z}).name ~= "air" then
	minetest.chat_send_player(player:get_player_name(), 'You can only sit down when you are not going to bonk your head.')
	return
end