computer-craft/makefloor

local args = { ... }

turnedLeft = nil
if args[1] == "rightturn" or args[1] == "leftturn" then
  local turnedLeft = args[1] == "rightturn"
else
  print("usage: \"makefloor [leftturn|rightturn] whatever the first turn may be")
  return
end

local curContainer = 1

local function selectMatStack()
  itemCount = turtle.getItemCount(curContainer)
  while itemCount == 0 do
    if curContainer == 10 then
      return false
    end
    curContainer = curContainer + 1
    turtle.select(curContainer)
  end
  return true
end

local function checkIfNextTurn()
  if turnedLeft then turnAction = turtle.TurnRight else turnAction = turtle.TurnLeft end
  turnAction()
  retval = not turtle.detect()
  if not turnedLeft then turnAction = turtle.TurnRight else turnAction = turtle.TurnLeft end
  turnAction()
  return retval
end

local function fillblock()
  shouldTurn = turtle.detect()
  if shouldTurn then
    couldTurn = checkIfNextTurn()
  end

  turtle.up()
  if not selectMatStack() then
    return false
  end
  turtle.placeDown()
  if shouldTurn then
    if turnedLeft then turnAction = turtle.TurnRight else turnAction = turtle.TurnLeft end
    turnAction()
    turtle.forward()
    turnAction()
    turnedLeft = not turnedLeft
  else
    turtle.forward()
    turtle.down()
  end
end

while fillblock() do end