local tArgs = {...}
local distance = tonumber(tArgs[1])

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

local hasMoved = tonumber(0)
local toMove = tonumber(distance*2 - hasMoved)
local Home = tonumber(0)
local pause = false
local top = false

local fuelLevel = turtle.getFuelLevel()
local fuelNeeded = false

function fuelNeed()
	if fuelLevel < 100 then
		fuelNeeded = true
	else
		fuelNeeded = false
	end
end

function fuel()
	if fuelLevel == "unlimited" then
		return true
	end

	if fuelLevel > 100 then
		return true
	end

	if fuelLevel < 100 then
	pause = true
		if hasMoved < distance then
			turtle.turnLeft()
			turtle.turnLeft()
			for i=1, hasMoved do
				turtle.forward()
				Home = Home + 1
			end
		end
		if hasMoved > distance then
			turtle.down()
			for i=1, toMove do
				turtle.forward()
				Home = Home + 1
			end
		end
	end

	if fuelLevel < 100 then
	if Home == toMove or hasMoved then
		print(" ")
		print("Out of fuel. Please refuel me")
		print("Place fuel in Slot 1 !!!")
		print("I will restart myself")

		fuelNeed()

		turtle.select(1)
		while fuelNeeded == true do
			turtle.refuel()
			sleep(3)
			fuelNeed()
			break
		end
		if fuelLevel > 100 then
			for i=1, Home do
				turtle.back()
				if top == true then
					turtle.up()
					top = false
				end
			end
		pause = false
		end
	end
	end
end

function digNormal()
	for i=1, distance do
	fuel()
		if pause == true then
			fuel()
		else
			turtle.dig()
			turtle.turnLeft()
			turtle.dig()
			turtle.turnRight()
			turtle.turnRight()
			turtle.dig()
			turtle.turnLeft()
			turtle.digDown()
			turtle.forward()
			hasMoved = hasMoved + 1
		end
	end
end

function digTop()
	for i=1, distance do
	fuel()
		if pause == true then
			fuel()
		else
			turtle.dig()
			turtle.digUp()
			turtle.turnLeft()
			turtle.dig()
			turtle.turnRight()
			turtle.turnRight()
			turtle.dig()
			turtle.turnLeft()
			turtle.forward()
			hasMoved = hasMoved + 1
		end
	end
end

function digUp()
	turtle.digUp()
	turtle.up()
	turtle.turnLeft()
	turtle.turnLeft()
	top = true
end

term.clear()
term.setCursorPos(1,1)

print("I'm going to mine "..distance.." blocks from here.")
sleep(2)
print("I will be back soon! Hopefully!")

if turtle.getFuelLevel() < 100 then
	turtle.refuel()
end
digNormal()
digUp()
digTop()