// The screensaver itself is a modified showcase;
// it uses the same state to avoid repeats,
// though it runs a lot slower and zooms in.
// And of course, the UI is hidden!

function screensaverNext() {
  showcaseMiku = nextShowcaseMiku;

  // I wrote a whole damn Newton-raphson equation solver to fit
  // setSize's lerping shenanigans to this so it'd be *poifect*.
  // It wasn't, reader. It was not poifect.
  // These magic constants will do well enough! ;-;

  let z = -6.5 - 1.75 * Math.log2(showcaseMiku.properties.clearance / IMGSIZE)

  console.log(showcaseMiku.properties.clearance, z)

  map.flyTo({
    'center': nextShowcaseMiku.geometry.coordinates,
    'zoom': z,
    'speed': 0.6,
  });
  displayMiku(showcaseMiku, true);

  showcase_i += 1;
  nextShowcaseMiku = MIKUS.features[
    showcase_i % MIKUS.features.length];
}


// We hide the UI elements, block the showcase
// and set a timer:

let screensaverActive = false;
let screensaverTimerID;

function startScreensaver() {
  const FLIGHT_TIME_S = 5;
  const LINGER_TIME_S = 15;
  console.log("Starting screensaver")
  showcaseBlockers.add("screensaver");
  document.body.classList.add('screensaver');
  let startTime = 5;
  window.setTimeout(screensaverNext, startTime * 1000)
  let loopTime = FLIGHT_TIME_S + LINGER_TIME_S;
  screensaverTimerID = window.setInterval(screensaverNext, (loopTime + startTime) * 1000);
  screensaverActive = true;
}

function stopScreensaver() {
  if (!screensaverActive) return;
  screensaverActive = false;
  console.log("Stopping screensaver")
  window.clearInterval(screensaverTimerID);
  showcaseBlockers.delete("screensaver");
  document.body.classList.remove('screensaver');

  // TODO: return to original location!
}


// After a minute of no activity*, the screensaver kicks in.
// When activity occurs again, the screen returns to its original location.
// *activity is defined as one of:


const TIMEOUT_MS = 60_000;
let activityCheckTimerID;
function activity(event) {
  // ignore maplibre-induced events
  if (event && !event.originalEvent) return;

  window.clearTimeout(activityCheckTimerID);
  activityCheckTimerID = window.setTimeout(startScreensaver, TIMEOUT_MS);
  stopScreensaver();
}
activity();

map.on('zoomstart', activity)
map.on('zoomend', activity)
map.on('movestart', activity)
map.on('moveend', activity)
document.getElementById('map').addEventListener('keydown', activity)