Filler

function needsFuel()
  if turtle.getFuelLevel() < 10 then
    return true
  else
    return false
  end
end

function refuel()
  turtle.select(16)
  turtle.refuel(1)
end

function invCheck()
  for slot = 1, 15 do
    if turtle.getItemCount(slot) == 0 then
      slot = slot + 1
      turtle.select(slot)
     end
  end
  if turtle.getItemCount(15) == 1 then
    print("Feed Me!")
    os.pullEvent(key)
    turtle.placeDown()
  end
end

function blockDown()
  while turtle.detectDown() == true do
    print("Finding Hole")
    turtle.turnRight()
    turtle.forward()
    turtle.turnRight()
    turtle.forward()
    turtle.turnLeft()
  end
end

function noblockDown()
  if turtle.detectDown() == false then
    turtle.select(1)
    invCheck()
    print("Placing Block")
    turtle.placeDown()
    turtle.forward()
  else blockDown()
  end
end

function fill()
  if needsFuel() then
    refuel()
  else noblockDown()
 end
end
    while true do
      fill()
    end