local font = "electronic_highway_sign"
local fontSize = vec2(48, 97)
local textColor = rgbm(1, 1, 1, 1)

local bestTimes = {}
local deltaTimes = {}
local isRace = false
local displayedCarCount = 6
local displayDuration = 3.0
local displayTimers = {}
local lastLapCount = {}
local updateInterval = 5.0
local updateTimer = 0


-- for best lap：mm:ss.mmm
local function formatBestTime(ms)
  if ms > 0 then
    local minutes = math.floor(ms / 60000)
    local seconds = math.floor((ms / 1000) % 60)
    local millis = math.floor(ms % 1000)
    return string.format("%d:%02d.%03d", minutes, seconds, millis)
  else
    -- return "0:00.000"
    return "--.---"
  end
end

-- for race : mm:ss.mmm
local function formatDeltaTimeLong(ms)
  if (ms==nil) then
      return "--.---"
  end
  local minutes = math.floor(ms / 60000)
  local seconds = math.floor((ms / 1000) % 60)
  local millis = math.floor(ms % 1000)
  return string.format("%d:%02d.%03d", minutes, seconds, millis)
end


local function formatDeltaTimeShort(timestamp)
    if (timestamp==nil) then
        return "--.---"
    end
    return string.format("%02.3f", timestamp/1000.0)
end


local sim = ac.getSim()

function script.update(dt)
    isRace = sim.raceSessionType == 3 and sim.isSessionStarted
    updateTimer = updateTimer - dt

    if isRace and updateTimer <= 0 then
        updateTimer = updateInterval
        deltaTimes = {}
        deltaTimes[1] = 0

        local cumulativeGap = 0

        for i = 1, displayedCarCount do
            local car = ac.getCar.leaderboard(i)
            local prevCar = ac.getCar.leaderboard(i - 1)

            if car and prevCar then
                if car.isInPit or car.isInPitlane or car.isRetired then
                    --   deltaTimes[i] = "pit"
                    deltaTimes[i] = "PIT"
                    cumulativeGap = -1
                else
                    local gap = ac.getGapBetweenCars(car.index, prevCar.index)
                    if math.abs(gap) < 60*10 and cumulativeGap >= 0 then
                        cumulativeGap = cumulativeGap + gap
                        -- deltaTimes[i] = formatDeltaTime(cumulativeGap * 1000)
                        if math.abs(cumulativeGap) > 120 then
                            deltaTimes[i] = ">2MINUTE"
                        elseif math.abs(cumulativeGap) > 60 then
                            deltaTimes[i] = formatDeltaTimeLong(cumulativeGap * 1000)
                        else
                            deltaTimes[i] = formatDeltaTimeShort(cumulativeGap * 1000)
                        end
                    else
                        deltaTimes[i] = "-"
                        cumulativeGap = -1
                    end
                end
            end
        end
    end



    if isRace then
        for i = 1, displayedCarCount do
            local car = ac.getCar.leaderboard(i)
            if car then
            local yOffset = (i - 1) * 80

            display.text {
                pos = vec2(0, yOffset),
                letter = fontSize,
                text = deltaTimes[i],
                -- alignment = 1,
                font = font,
                spacing = -9,
                color = textColor
            }
            end
        end


    else
        -- not race
        for i = 1, displayedCarCount do
        local car = ac.getCar.leaderboard(i)
        if car then
            local lapTime = car.bestLapTimeMs
            if lapTime > 0 then
            bestTimes[car.index] = lapTime
            end
            display.text {
            pos = vec2(0, -78 + i * 80),
            letter = fontSize,
            text = formatBestTime(bestTimes[car.index] or 0),
            font = font,
            spacing = -9,
            color = textColor
            }
        end
        end
    end
end