Accident Counter for MC

local monitor = peripheral.wrap("back")
local seconds = 0
local minutes = 0
local hours = 0
local days = 0

local filename = "counter_save.mag"

function ticker ()
    while true do
        seconds = seconds + 1

        if seconds == 60 then
            seconds = 0
            minutes = minutes + 1

            os.remove(filename)
            file = io.open(filename, "w")
            if file != nil then
                file:write(minutes)
                file:write(hours)
                file:write(days)

                file:close()
            end
        end

        if minutes == 60 then
            minutes = 0
            hours = hours + 1
        end

        if hours == 24 then
            hours = 0
            days = days + 1
        end

        myString = tonumber(days) .. ":" .. tonumber(hours) .. ":" .. tonumber(minutes) .. ":" .. tonumber(seconds)

        monitor.clear()

        monitor.setCursorPos(1,1)
        monitor.write("Accident free for")

        local x,y = monitor.getSize()

        monitor.setCursorPos(1 + math.ceil((x/2)-(myString:len()/2)), math.ceil(y/2))
        monitor.write(myString)

        sleep(1)
    end
end

function resetter ()
    while true do
        term.setTextColor(colors.white)

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

        term.write("Enter reset password:")

        local pwd = read("*")

        if pwd == "whoopsie" then
            break
        else
            term.setTextColor(colors.red)
            term.clear()
            term.setCursorPos(1,1)

            term.write("bad password")
            sleep(3)
        end
    end
end

--startup--
file = io.open(filename, "r")
if file != nil then
    minutes = file:read("n")
    hours = file:read("n")
    days = file:read("n")

    file:close()
end

--main--
while true do
  parallel.waitForAny(ticker, resetter)

  term.setTextColor(colors.lime)
  term.clear()
  term.setCursorPos(1,1)
  term.write("password accepted, counter reset")

  sleep(3)
end