Kekimurus

inv=peripheral.wrap("top")

local function getcake()
    for i=1,inv.size() do
        slotmeta=inv.getItemMeta(i)
        if slotmeta~=nil and slotmeta.name=="minecraft:cake" then
            inv.pushItems("down",i,1,1)
            return
        end
    end
end


--test if there is cake below, if not then place
while true do
    if turtle.getItemCount(1)<1 then
        getcake()
    end
    local success,blockdata=turtle.inspectDown()
    if blockdata.name ~=nil and string.find(blockdata.name, "minecraft:cake") then
        --print("cake found")
        sleep(1)
    else --place cake
        turtle.select(1)
        turtle.placeDown()
    end
end