Room Maker (square, 3-high)

local tArgs = { ... }
if #tArgs ~= 1 then
		print( "Usage: makeroom <size>" )
		return
end
-- Mine in a spiral pattern
local size = tonumber( tArgs[1] )
if size < 1 then
		print( "Room size must be positive" )
		return
end
	  
local collected = 0
local function collect()
		collected = collected + 1
		if math.fmod(collected, 25) == 0 then
				print( "Mined "..collected.." items." )
		end
end
local function tryDig()
		while turtle.detect() do
				if turtle.dig() then
						collect()
						sleep(0.5)
				else
						return false
				end
		end
		return true
end
local function tryDigUp()
		while turtle.detectUp() do
				if turtle.digUp() then
						collect()
						sleep(0.5)
				else
						return false
				end
		end
		return true
end
local function tryDigDown()
		while turtle.detectDown() do
				if turtle.digDown() then
						collect()
						sleep(0.5)
				else
						return false
				end
		end
		return true
end
local function refuel()
		local fuelLevel = turtle.getFuelLevel()
		if fuelLevel == "unlimited" or fuelLevel > 0 then
				return
		end
	  
		local function tryRefuel()
				for n=1,16 do
						if turtle.getItemCount(n) > 0 then
								turtle.select(n)
								if turtle.refuel(1) then
										turtle.select(1)
										return true
								end
						end
				end
				turtle.select(1)
				return false
		end
	  
		if not tryRefuel() then
				print( "Add more fuel to continue." )
				while not tryRefuel() do
						sleep(1)
				end
				print( "Resuming Room." )
		end
end
local function tryUp()
		refuel()
		while not turtle.up() do
				if turtle.detectUp() then
						if not tryDigUp() then
								return false
						end
				elseif turtle.attackUp() then
						collect()
				else
						sleep( 0.5 )
				end
		end
		return true
end
local function tryDown()
		refuel()
		while not turtle.down() do
				if turtle.detectDown() then
						if not tryDigDown() then
								return false
						end
				elseif turtle.attackDown() then
						collect()
				else
						sleep( 0.5 )
				end
		end
		return true
end
local function tryForward()
		refuel()
		while not turtle.forward() do
				if turtle.detect() then
						if not tryDig() then
								return false
						end
				elseif turtle.attack() then
						collect()
				else
						sleep( 0.5 )
				end
		end
		return true
end
local function channelForward(length)
   refuel()
   for i=1,length do
	  tryDigUp()
	  tryDigDown()
	  tryForward()
  end
  return true
end
print( "Making Room..." )
n=1
while n < size do
		channelForward(n)
turtle.turnRight()
		channelForward(n)
turtle.turnRight()
n=n+1
end
channelForward(n-1)
tryDigUp()
tryDigDown()
print( "Room complete." )
print( "Mined "..collected.." items total." )