spiral

local c_args = { ... }

local target_depth = tonumber(c_args[1])

local function find_item()
    for slot_index = 1, 16 do
        if turtle.getItemCount(slot_index) > 0 then
            return slot_index
        end
    end

    return -1
end

local function try_place_down()
    if not turtle.placeDown() then
        local slot = find_item()

        if slot == -1 then
            error("can't place, out of blocks")
        end

        turtle.select(slot)

        try_place_down()
    end
end

for i = 1, target_depth do
    try_place_down()
    turtle.forward()
    turtle.down()

    if i % 10 == 0 then
        turtle.turnRight()
    end
end