Function setActiveIndex

assets/main.js:993–1016

(index, { emit = false, force = false } = {})

  };

  const setActiveIndex = async (index, { emit = false, force = false } = {}) => {
    if (!Number.isFinite(index)) return null;
    const safeIndex = Math.round(index);
    if (safeIndex < 0 || safeIndex >= timelineSnapshots.length) return null;
    if (!force && state.activeIndex === safeIndex) return timelineSnapshots[safeIndex];
    if (state.loading && !force) return null;

    state.activeIndex = safeIndex;
    slider.value = String(safeIndex);

    const snapshot = timelineSnapshots[safeIndex];
    summary.textContent = snapshot.label;
    label.textContent = formatSnapshotDescription(snapshot);

    const metricsText = formatTimelineMetrics(snapshot.metrics);
    metricsElement.textContent = metricsText || "";
    metricsElement.classList.toggle("timeline-metrics--empty", metricsText.length === 0);

    if (emit) {
      await applySnapshotChange(snapshot, safeIndex);
    }

    return snapshot;
  };

  slider.addEventListener("input", (event) => {
    const nextIndex = Number(event.target.value);