Function _scheduleNext

static/js/chunkedAudioEngine.js:259–282

()

  // --- lookahead scheduler ---

  async function _scheduleNext() {
    const chunkIdx = Math.floor(_scheduledTo / CHUNK_SEC);
    _fetchChunk(chunkIdx + 1); // fire-and-forget pre-fetch of the chunk after

    // Use the synchronous result if already decoded, otherwise await.
    const hit = _cache.get(chunkIdx);
    const buffers = hit?.result ?? await _fetchChunk(chunkIdx);
    if (!playing || destroyed) return;
    if (!buffers || buffers.size === 0) return; // past end; tick() handles onEnded

    // With SoundTouch, sources play at 1.0x so scheduled wall-clock time equals
    // audio time. With tape-effect (_playbackRate != 1, no stNode), sources play
    // faster/slower so wall-clock time = audio seconds / _playbackRate.
    const playFactor = stNode ? 1.0 : _playbackRate;
    const idealWhen = _startCtxTime + (_scheduledTo - _startOffset) / playFactor;
    const when = Math.max(idealWhen, ctx.currentTime + 0.01);
    // If we're late (slow network), skip the audio portion that already "passed".
    const firstBuf = buffers.values().next().value;
    const maxSkip = firstBuf ? Math.max(0, firstBuf.duration - 0.001) : 0;
    const bufOffset = Math.min(Math.max(0, when - idealWhen) * playFactor, maxSkip);

    const dur = _scheduleChunk(buffers, when, bufOffset);
    _scheduledTo += bufOffset + dur; // always advances by ~CHUNK_SEC
  }

  function _maybeSchedule() {
    if (_filling || !playing || destroyed) return;