straight

local fuel = {}
fuel['chest'] = 1
fuel['material'] = 2

local fill = {}
fill['chest'] = 3
fill['material'] = 4

local loot = {}
loot['chest'] = 5
loot['material'] = 6
loot['lastItem'] = true

local firstSlot = 6

local function placeChest(item)
	turtle.turnLeft()
	turtle.turnLeft()

	if turtle.detect() then
		error("Block behind us")
	end

	turtle.select(item.chest)

	if turtle.place() == false then
		error("Failed to place chest from slot " .. item.chest)
	end
end

local function getChest(item)
	turtle.select(item.chest)

	if turtle.dig() == false then
		error("Failed to retreive chest to slot " .. item.chest)
	end

	turtle.turnLeft()
	turtle.turnLeft()
end

local function unload(item)
	placeChest(item)

	if item.lastItem then
		for n=item.material,16 do
			turtle.select(n)
			turtle.drop()
		end
	else
		turtle.select(item.material)
		turtle.drop()
	end

	getChest(item)
end

local function reload(item)
	placeChest(item)

	turtle.select(item.material)
	while turtle.getItemSpace() > 0 do
		if turtle.suck(turtle.getItemSpace()) == false then
			error("Couldn't get an item for slot " .. item.material)
		end
	end

	getChest(item)
end

local function refuel(item, fuelLimit)
	if fuelLimit == nil then
		fuelLimit = turtle.getFuelLimit()
	end

	while turtle.getFuelLevel() < fuelLimit do
		turtle.select(item.material)
		if turtle.getItemCount() > 1 then
			turtle.refuel(turtle.getItemCount() - 1)
		else
			reload(item)
		end
	end
end

local Item = {}
Item["detect"] = {}
Item["detect"]["forward"] = turtle.detect
Item["detect"]["left"] = turtle.detect
Item["detect"]["right"] = turtle.detect
Item["detect"]["up"] = turtle.detectUp
Item["detect"]["down"] = turtle.detectDown
Item["place"] = {}
Item["place"]["forward"] = turtle.place
Item["place"]["left"] = turtle.place
Item["place"]["right"] = turtle.place
Item["place"]["up"] = turtle.placeUp
Item["place"]["down"] = turtle.placeDown
local function place(item, direction)
	turtle.select(item.material)
	if turtle.getItemCount() <= 1 then
		reload(item)
	end

	if direction == "left" then
		turtle.turnLeft()
	elseif direction == "right" then
		turtle.turnRight()
	end

	if Item["detect"][direction]() == false then
		if Item["place"][direction]() == false then
			error("Failed to place an item from slot " .. item.material)
		end
	end

	if direction == "left" then
		turtle.turnRight()
	elseif direction == "right" then
		turtle.turnLeft()
	end
end

local function isFull()
	for n=firstSlot,16 do
		if turtle.getItemCount(n) == 0 then
			--Empty slots
			return false;
		end
	end
	print( "No empty slots left." )
	return true;
end

local function forwards()
	if turtle.getFuelLimit() ~= 0 and turtle.getFuelLevel() < 10000 then
		refuel(fuel, 20000)
	end

	if isFull() then
		unload(loot)
	end

	turtle.select(loot.material)
	while not turtle.forward() do
		if not turtle.dig() then
			if turtle.attack() then
				-- Do Nothing
			else
				sleep( 0.5 )
			end
		end
	end
	return true
end

-----------------------------------------------------------------------------
--Main Program
-----------------------------------------------------------------------------
local tArgs = { ... }
if #tArgs < 1 then
	print( "My Version Usage: straight length [number]" )
	return
end

local length = tonumber( tArgs[1] )
local turtleNumber
if tArgs[2] ~= nil then
	turtleNumber = tonumber( tArgs[2] )
else
	turtle = tonumber( os.getComputerLabel() )
end

print( "Tunneling..." )
reload(fuel)
reload(fill)

--Tunnel forward filling in the edge
for tunnelLength=1,length do
	print("Mining " .. tunnelLength .. " / " .. length)

	forwards()

	--Fill your edge
	if turtleNumber == 1 then
		place(fill, "up")
		place(fill, "left")
	elseif turtleNumber == 2 then
		place(fill, "up")
	elseif turtleNumber == 3 then
		place(fill, "up")
		place(fill, "right")
	elseif turtleNumber == 4 then
		place(fill, "left")
	elseif turtleNumber == 5 then
		-- Place Nothing
	elseif turtleNumber == 6 then
		place(fill, "right")
	elseif turtleNumber == 7 then
		place(fill, "down")
		place(fill, "left")
	elseif turtleNumber == 8 then
		place(fill, "down")
	elseif turtleNumber == 9 then
		place(fill, "right")
		place(fill, "down")
	end
end

print( "Emptying" )
unload(fuel)
unload(fill)
unload(loot)

print( "Done" )