Turtle "Minen"

term.clear()
term.setCursorPos(1,1)

print("Turtle Miner v.1.3")
print("")
print("Die Turtle wird einen 3x3 Gang graben")
print("Wie lange graben?")

local length = read()
local torch = 0
local left = length

function checkFuel()
    if turtle.getFuelLevel() < 15 then
        turtle.select(1)
        turtle.refuel()
    end
end
function digBlock()
    while turtle.detect() do
        turtle.dig()
        os.sleep(0.5)
    end
end
function digBlockUp()
    while turtle.detectUp() do
        turtle.digUp()
        os.sleep(0.5)
    end
end
function status()
    print("[Slot 1] Treibstoff   [Slot 2] Fackeln")
    print("")
    print("Reihen uebrig : "..left)
    print("Treibstoff : "..turtle.getFuelLevel())
end

function digLayer()
    for i=1,2 do
        turtle.turnLeft()
        digBlock()
        turtle.turnRight()
        turtle.turnRight()
        digBlock()
        turtle.turnLeft()
        digBlockUp()
        turtle.up()
    end
    turtle.turnLeft()
    digBlock()
    turtle.turnRight()
    turtle.turnRight()
    digBlock()
    if torch == 8 then
        turtle.forward()
        turtle.turnRight()
        turtle.forward()
        turtle.select(2)
        turtle.placeDown()
        turtle.back()
        turtle.turnLeft()
        turtle.back()
        torch = 0
    end
    turtle.turnLeft()
    turtle.down()
    turtle.down()
    torch = torch + 1
    left = left - 1
end

for i=1,length do
    turtle.dig()
    turtle.forward()
    term.clear()
    term.setCursorPos(1,1)
    checkFuel()
    status()
    digLayer()
end

term.clear()
term.setCursorPos(1,1)
checkFuel()
status()
turtle.turnRight()
turtle.turnRight()
for i=0,length-3 do
    turtle.forward()
end
term.clear()
term.setCursorPos(1,1)
checkFuel()
status()
print("Fertig!")