Quarry v4.0

function numbItemsInInv()
  items = 0
  for i = 1, 16 do
    items = items + turtle.getItemCount(i)
  end
  return items
end

function forward(forw)
  if tonumber(forw) == nil then
    forw = 1
  end
  for i = 1,forw do
    while not turtle.forward() do
      turtle.dig()
      turtle.attack()
    end
  end
end

function up(up)
  if tonumber(up) == nil then
    up = 1
  end
  for i = 1,tonumber(up) do
    while not turtle.up() do
      turtle.digUp()
      turtle.attackUp()
    end
  end
end

function empty()
  turtle.select(16)
  up()
  turtle.down()
  turtle.placeUp()
  items = numbItemsInInv()
  while items ~= 0 do
    print("Try to empty the turtle's inventory")
    for i = 1,16 do
      turtle.select(i)
      turtle.dropUp()
    end
    items = numbItemsInInv()
    if items ~= 0 then
      print("Failed to empty inventory")
      sleep(5)
    end
  end
  print("Inventory is empty!")
  sleep(8)
  turtle.select(1)
  turtle.digUp()
  turtle.transferTo(16)
  return
end

function inv()
  if turtle.getItemCount(15) > 0 then
    empty()
  end
  return
end

function refuel()
  fuel = turtle.getFuelLevel()
  while fuel < 300 do
    print("I don't have enough fuel!")
    turtle.refuel()
    sleep(2)
  end
  print("I got enough fuel!")
  return
end

function columnd(depth)
  refuel()
  for i = 1,tonumber(depth) do
    turtle.digDown()
    turtle.down()
    for i = 1,4 do
      turtle.dig()
      turtle.turnLeft()
    end
    inv()
  end
end

function columna(depth)
  refuel()
  for i = 1,tonumber(depth) do
    for i = 1,4 do
      turtle.dig()
      turtle.turnLeft()
    end
    inv()
    turtle.digUp()
    turtle.up()
  end
end

function clean(depth)
  for i = 1,tonumber(depth) do
    turtle.digDown()
    turtle.down()
    turtle.dig()
    inv()
  end
  turtle.turnRight()
  forward(1)
  turtle.turnLeft()
  for i = 1,tonumber(depth) do
    turtle.dig()
    up(1)
    inv()
  end
  empty()
end

function checkEnder()
  chest = turtle.getItemCount(16)
  if chest == 0 then
    print("I need an enderchest in slot 16!")
    sleep(2)
       os.reboot()
  else
       return
  end
end

function four(four)
  columnd(four)
  empty()
  forward(3)
  columna(four)
  empty()
  turtle.turnLeft()
  forward(3)
  turtle.turnRight()
  columnd(four)
  empty()
  turtle.turnLeft()
  turtle.turnLeft()
  forward(3)
  turtle.turnRight()
  turtle.turnRight()
  columna(four)
  empty()
  forward(1)
  turtle.turnRight()
  forward(1)
  turtle.turnLeft()
  clean(four)
  print("I'm done!")
end