Function isBackwardNavigationInLocalHistory

isBackwardNavigationInLocalHistory(
    newTrackId: string,
    previousTrackId: string,
    progressPercent: number,
): boolean

Not Exported

Check if navigating to a previous track based on local history

Analyzes the local track history to determine if a track change appears to be backward navigation (i.e., the user clicked "previous") rather than a skip or normal track progression.

This function uses a sophisticated algorithm that considers:

Position of the track in recent history
Timing of recent navigations
Progress through the current track
Navigation patterns and behaviors

Parameters

newTrackId: string
ID of the track being navigated to
previousTrackId: string
ID of the track being navigated from
progressPercent: number
How far through the previous track the user was (0.0-1.0)

Returns boolean

Whether this appears to be backward navigation

Example

// Check if a track change was backward navigation
const wasGoingBack = isBackwardNavigationInLocalHistory(
  newTrackId,
  previousTrackId,
  0.15 // User was 15% through the previous track
);

if (wasGoingBack) {
  console.log('User navigated to a previous track (clicked prev button)');
}

Source

function isBackwardNavigationInLocalHistory(
  newTrackId: string,
  previousTrackId: string,
  progressPercent: number,
): boolean {
  if (!newTrackId || recentlyPlayedHistory.length <= 1) return false;

  const now = Date.now();

  // If we're coming from a track we recently navigated to,
  // this is probably a skip, not backward navigation
  if (
    lastNavigatedToTrackId === previousTrackId &&
    now - lastNavigationTimestamp < NAVIGATION_EXPIRY_TIME &&
    progressPercent < 0.3 // Less than 30% through the track
  ) {
    store.saveLog(
      `User likely skipping a previously navigated-to track (${previousTrackId})`,
      "DEBUG",
    );
    return false;
  }

  // Skip the first entry (current track) and look for the new track ID
  let positionInHistory = -1;
  for (let i = 1; i < recentlyPlayedHistory.length; i++) {
    if (recentlyPlayedHistory[i].id === newTrackId) {
      positionInHistory = i;
      break;
    }
  }

  if (positionInHistory === -1) return false;

  // Only consider it backward navigation if:
  // 1. The track is in our recent history (position found)
  // 2. It's relatively recent (one of the last 10 tracks)
  // 3. OR it was played very recently (last 2 minutes)
  const isRecentPosition = positionInHistory < 10;
  const trackTimestamp = recentlyPlayedHistory[positionInHistory].timestamp;
  const isRecentTime = now - trackTimestamp < 120000; // 2 minutes

  if (isRecentPosition || isRecentTime) {
    store.saveLog(
      `Local history indicates backward navigation to previously played track at position ${positionInHistory}`,
      "DEBUG",
    );

    // Remember this as a backward navigation for future reference
    lastNavigatedToTrackId = newTrackId;
    lastNavigationTimestamp = now;

    return true;
  }

  // If the track is in history but not recent, don't consider it backward navigation
  // This handles the case of skipping to a track that was played long ago
  return false;
}