Minecraft Turtle: Hallway

--[[
    2013 (c) psychedelixx
    Minecraft Turtle: Hallway
    2013-05-21

    Digs a simple hallway and places missing ground blocks and torches (every 11th horizontal block).

    Usage:
    - use turtle and type "label set <name>"
      (to give your turtle an unique name so it remembers its programs)
    - type "pastebin get VnRd9e6C hallway"
    - place solid blocks in slot 16 (lower right corner)
    - place torches in slot 15 (left of slot 16)
    - type "hallway <length>"
        • where <length> represents the maximum length of the hallway
--]]

local args = { ... }
if #args < 1 then
  print( "Usage: hallway <length>" )
  error()
end
limit = tonumber(args[1])

if turtle.getFuelLevel() == 0 then
    turtle.refuel()
end

if turtle.getFuelLevel() == 0 then
    print("I need fuel!")
else
    print("======== 2013 (c) psychedelixx ========")
    print("Let's go!")

    torchCount = 0

    while turtle.getFuelLevel() > 0 and limit > 0 do
        print("")
        print("Remaining: " .. limit)
        print("Fuel: " .. turtle.getFuelLevel())
        print("Next torch in: " .. 11-torchCount%11 .. "m")

        turtle.dig()
        turtle.forward()
        turtle.digUp()

        if not turtle.detectDown() then
            turtle.select(16)
            turtle.placeDown()
        end

        if torchCount%11 == 0 then
            turtle.turnRight()
            turtle.dig()
            turtle.select(15)
            turtle.place()
            turtle.turnLeft()
        end
        limit = limit-1
        torchCount = torchCount + 1
        if limit > 0 and turtle.getFuelLevel() < 2 then
            turtle.refuel()
        end
    end
end