CrystalMiner

function forward(amount)
  for i = 1, amount, 1 do
    turtle.dig()
    turtle.forward()
  end
end

function refuel()
  print( "Refueling..." )

  turtle.select(1)
  turtle.suckDown(64)
  turtle.refuel(64)
end

function dumpItems()
  local freeSlots = false
  for n=1,16 do
        local itemCount = turtle.getItemCount(n)
        if itemCount > 0 then
            turtle.select(n)
            turtle.drop(64)
    else
      freeSlots = true
        end
    end

  return freeSlots
end

function mainLoop()
  while true do
    if turtle.getFuelLevel() < 1000 then
      refuel()
    end

    forward(9)
    turtle.turnRight()
    forward(1)
    turtle.digUp()
    turtle.up()
    turtle.turnRight()
    forward(9)
    turtle.up()
    turtle.turnRight()
    forward(1)
    turtle.turnRight()
    forward(9)
    turtle.turnLeft()
    forward(1)
    turtle.digDown()
    turtle.down()
    turtle.turnLeft()
    forward(9)
    turtle.turnLeft()
    forward(1)
    turtle.turnRight()
    turtle.down()
    dumpItems()
    turtle.turnRight()
    turtle.turnRight()

    sleep(3600)
  end
end

mainLoop()