[WIP] Mining Turtle Hollow squared

local tArgs = {...}

if #tArgs ~= 1 then
  print("Usage: Hollow <diameter>")
  return
end

local size = tonumber(tArgs[1])

if size < 1 then
  print("Diameter must be positive!")
  return
end

local dist = 0
local dist2 = 0
local dist3 = 0
local dist4 = 0
local depth = - 1
local continuingSize = size - 1
local totalDist = 1

--TODO
--Disable ItemOverflow

--Unload all collected Items
local function unloadItems()

  for i = 0, depth, 1 do
    turtle.up()
  end

  print("Unloading items while waiting for fuel...")

  for i = 1, 16, 1 do
    turtle.select(i)
    turtle.drop()
  end

  turtle.select(1)

  print("All items unloaded.")

  return
end

--Moving Back
local function moveDist(distance)
  for i = 0, distance, 1 do
    turtle.forward()
  end
end

local function move2()
  moveDist(dist2)
  turtle.turnRight()
  moveDist(dist)
end

local function move3()
  moveDist(dist3)
  turtle.turnRight()
  moveDist(dist2)
  turtle.turnRight()
  moveDist(dist)
end

local function move4()
  moveDist(dist4)
  turtle.turnRight()
  moveDist(dist3)
  turtle.turnRight()
  moveDist(dist2)
  turtle.turnRight()
  moveDist(dist)
end

--Checks for fuel
local function checkForFuel()
  for i = 1, 16, 1 do
    turtle.select(i)
    if turtle.getFuelLevel() <= totalDist and turtle.refuel() == true then
      print("Refuelled successfully!")
      turtle.refuel()
    end
  end
  turtle.select(1)
end

if turtle.getFuelLevel() < 1 and turtle.refuel() == false then
  print("I need fuel!")
  return
elseif turtle.getFuelLevel() < 1 then
  print("First refuel.")
  turtle.refuel()
  print(turtle.getFuelLevel())
else
print("Digging...")
end

--Goes until Bedrock
while turtle.digDown() == true do
  turtle.digDown()
  turtle.down()
  depth = depth + 1
  totalDist = totalDist + 1
  write("Going down. Depth: ")
  print(depth)

  --First Lane

  for i = 1, continuingSize, 1 do
    turtle.dig()
    turtle.forward()

    if depth < 1 then
      dist = dist + 1
      totalDist = totalDist + 1
    end

    if turtle.getFuelLevel() <= totalDist then
      print("Trying to refuel.")
      checkForFuel()

      if turtle.getFuelLevel() <= totalDist then
        print("Not enough fuel...going back.")

        turtle.turnLeft()
        turtle.turnLeft()

        moveDist(dist)

        unloadItems()
        return
      end
    end
  end

  turtle.turnLeft()

  --Second Lane

  for i = 1, continuingSize, 1 do

    turtle.dig()
    turtle.forward()

    if depth < 1 then
      dist2 = dist2 + 1
      totalDist = totalDist + 1
    end

    if turtle.getFuelLevel() <= totalDist then
      print("Trying to refuel.")
      checkForFuel()

      if turtle.getFuelLevel() <= totalDist then
        print("Not enough fuel...going back.")

        turtle.turnLeft()
        turtle.turnLeft()

        move2()

        unloadItems()
        return
      end
    end
  end

  turtle.turnLeft()

  --Third Lane

  for i = 1, continuingSize, 1 do

    turtle.dig()
    turtle.forward()

    if depth < 1 then
      dist3 = dist3 + 1
      totalDist = totalDist + 1
    end

    if turtle.getFuelLevel() <= totalDist then
      print("Trying to refuel.")
      checkForFuel()

      if turtle.getFuelLevel() <= totalDist then
        print("Not enough fuel...going back.")

        turtle.turnLeft()
        turtle.turnLeft()

        move3()

        unloadItems()
        return
      end
    end
  end

  turtle.turnLeft()

  --Forth Lane

  for i = 1, continuingSize, 1 do

    turtle.dig()
    turtle.forward()

    if depth < 1 then
      dist4 = dist4 + 1
      totalDist = totalDist + 1
    end

    if turtle.getFuelLevel() <= totalDist then
      print("Trying to refuel.")
      checkForFuel()

      if turtle.getFuelLevel() <= totalDist then
        print("Not enough fuel...going back.")

        turtle.turnLeft()
        turtle.turnLeft()

        move4()

        unloadItems()
        return
      end
    end
  end

  turtle.turnLeft()
end