PlatformBuilderV2

-- Input Variabls for length and width of platform
local inVars = {...}

local width = tonumber(inVars[1])
local length = tonumber(inVars[2])

local widthCount = tonumber(0)

-- place a block below turtle till length is reached
function buildForward()

        for i=1, length do
                checkInv()
                turtle.placeDown()
                turtle.forward()
        end
end

-- reorient turtle to the right
function spinRight()

        turtle.turnRight()
        turtle.forward()
        turtle.turnRight()
        turtle.forward()

end

-- reorient turtle to the left
function spinLeft()

        turtle.turnLeft()
        turtle.forward()
        turtle.turnLeft()
        turtle.forward()

end

function checkInv()

        if turtle.getItemCount( turtle.getSelectedSlot()) == 0 then
		turtle.select(turtle.getSelectedSlot() + 1)
	elseif turtle.getSelectedSlot() == 16 then
   		os.shutdown()
 	end

end

--Main program loop

while true do

	buildForward()
	spinRight()
	widthCount = widthCount + 1
	if widthCount == width then
		break
	end
	buildForward()
	spinLeft()
	widthCount = widthCount + 1
	if widthCount == width then
		break
	end

end