miner

function clearscreen()
  term.clear()
  term.setCursorPos(1,1)
end

function select(a)
  turtle.select(a)
end

function fuel()
  if(turtle.getFuelLevel()<20) then
    select(1)
    if(turtle.getItemCount()>1) then
      turtle.refuel(1)
      print("Turtle refueled")
    else
      print("Please refuel!")
      while turtle.getItemCount()<2 do
        sleep(3)
      end
      turtle.refuel(1)
      print("Turtle refueled")
    end
  end
end

turtle.digDown()
while true do
  print("Distance to mine?")
  distance = read()
  Num = tonumber(distance)
  print("Pause between iterations (seconds):")
  Sleep = read()
  SleepNum = tonumber(Sleep)
  if Num then
    for i=1,Num do
      clearscreen()
      print("Distance mined: "..string.format(i))
      print("Distance left: "..string.format(Num-i))
      print("Fuel level: "..string.format(turtle.getFuelLevel()))
      fuel()
      turtle.digDown()
      select(4)
      turtle.placeDown()
      turtle.back()
      select(2)
      turtle.placeDown()
      select(3)
      turtle.place()
      for a=5,16 do
        select(a)
        if turtle.getItemCount()>0 then
          turtle.dropDown(64)
        end
      end
      sleep(SleepNum)
      select(2)
      turtle.digDown()
      turtle.dig()
      turtle.forward()
      turtle.digDown()
      while turtle.detect()==true do
        turtle.dig()
      end
      turtle.forward()
    end
  end
end