-- Vars
local args = {...}
local startTime
local lastTime

-- Functions
function GoForward()
    while(turtle.forward() == true) do
    end
end

function GoBack()
    while(turtle.back() == true) do
    end
end

function DoWork()
    redstone.setOutput("bottom", true)
    sleep(0.1)
    redstone.setOutput("bottom", false)

    while(turtle.forward() == true) do
        redstone.setOutput("bottom", true)
        sleep(0.1)
        redstone.setOutput("bottom", false)
    end
    GoBack()
end

-- Code
if(args[1] == nil) then
    print("Error: Smeltery <time (s)>")
    print("Note: 14 seconds = 1 go")
    return
end

GoForward()
turtle.turnLeft()
turtle.turnLeft()

startTime = os.clock()
while(true) do
    lastTime = os.clock()
    if(lastTime - startTime + 14 > tonumber(args[1])) then
        print("Job done after ".. lastTime - startTime .." seconds.")
        return
    end
    DoWork()
    while(true) do
        sleep(1)
        if(os.clock() - lastTime >= 14) then
            break
        end
    end
end