stairs.lua

height = 4
level = height - 1
length = 16
fuelslot = 1

local tArgs = { ... }
if #tArgs ~= 3 then
        print( "Usage: stairs <width> <height> <depth>" )
        return
end

height = tonumber(tArgs[2])
level = height - 1
length = tonumber(tArgs[1])
depth = tonumber(tArgs[3])

function movedown()
    if turtle.detectDown() then
        turtle.digDown()
    end
    turtle.down()
end

test = 20

function moveup()
    if turtle.detectUp() then
        turtle.digUp()
    end
    turtle.up()
end

function turnright()
    turtle.turnRight()
end

function moveforward()
    while turtle.detect() do
        turtle.dig()
    end
    turtle.forward()
end

function hasfuel()
    if turtle.getFuelLevel() == 0 then
        return true
    end
    tried = false
    while turtle.getFuelLevel() < 64 do
        turtle.select(1)
        if not turtle.refuel(1) then
            if not tried then
                print("Waiting for fuel")
            end
            tried = true
            sleep(5)
        end
    end
    test = test - 1
    return test > 0
end

function moveupMulti(i)
    i = i - 1
    while i > 0 do
       moveup()
       i = i - 1
    end
end

distance = 0

while hasfuel() do
    level = height - 1
    while level > 0 do
       movedown()
       level = level - 1
    end
    if depth <= 0 then
        break
    end
    moveupMulti(height - 1)
    distance = distance + 1
    if distance > length then
        distance = 0
        turnright()
    end
    moveforward()
end