spire

-- spire.lua
-- A program to build a spire using a turtle
-- Requires a chest with fuel and building materials next to the turtle

local height = 100 -- the height of the spire
local floor = 10 -- the interval of floors
local iron = 1 -- the slot for iron blocks
local copper = 2 -- the slot for copper blocks
local diamond = 3 -- the slot for diamond blocks

-- Refuel from the chest if needed
function refuel()
  if turtle.getFuelLevel() < 10 then
    turtle.turnLeft()
    turtle.suck()
    turtle.refuel()
    turtle.turnRight()
  end
end

-- Select a slot and place a block
function place(slot)
  turtle.select(slot)
  turtle.placeDown()
end

-- Build one layer of the spire
function layer()
  place(iron)
  turtle.forward()
  place(copper)
  turtle.forward()
  place(iron)
  turtle.turnRight()
  turtle.forward()
  place(copper)
  turtle.forward()
  place(iron)
  turtle.turnRight()
end

-- Build one floor of the spire
function floor()
  for i = 1, 4 do
    layer()
  end
end

-- Build a staircase to the next floor
function stairs()
  turtle.up()
  place(iron)
  turtle.forward()
  place(copper)
  turtle.up()
end

-- Build the spire
function spire()
  for i = 1, height do
    refuel()
    if math.mod(i,floor) == 0 then
      floor()
      stairs()
    else
      place(iron)
      turtle.up()
    end
  end
  place(diamond) -- top off with a diamond block
end

spire() -- start the program