boo-urns

private var lastOnUpdate = null;
private var lastOnShow = null;
private var lastLapAlert = null;
private var hotkeyReps = 0;
private var haveHotkey = 0;

private var cfgHotkey; // 0=disabled, 1=once, 2=twice

private const hotkeyThreshold = 2000; // ms

function onTimerLap() {
	lastLapAlert = System.getTimer();
	//...
}

function onUpdate(dc) {
	var now = System.getTimer();
	lastOnUpdate = now;
	//...
}

function onShow() {
	var now = System.getTimer();
	// ignore first onShow() within 8 seconds after lap alert
	if (lastLapAlert != null && lastOnShow != null && lastLapAlert > lastOnShow && now - lastLapAlert < 8000) {
		lastLapAlert = null;
	} else if (lastOnUpdate != null && cfgHotkey) {
		if (now - lastOnUpdate <= hotkeyThreshold * cfgHotkey) {
			hotkeyReps++;
			if (hotkeyReps >= cfgHotkey) {
				hotkeyReps = 0;
				haveHotkey = true;
				// trigger hotkey action
				// ...
			}
		}
	}
	lastOnShow = now;
	return false;
}