let scanInterval = null;

/* ============================================================
   UTILS
   ============================================================ */
function stopScanPolling() {
  if (scanInterval) {
    clearInterval(scanInterval);
    scanInterval = null;
  }
}

function updateScanUi(data) {
  const current = Number(data?.current || 0);
  const total = Number(data?.total || 0);

  const percent = Number.isFinite(Number(data?.percent))
    ? Number(data.percent)
    : total > 0
      ? Math.round((current / total) * 100)
      : 0;

  const eta = data?.eta || "calcolo...";

  const progressEl = document.getElementById("scanProgress");
  const etaEl = document.getElementById("scanEta");
  const barEl = document.getElementById("progressBar");

  if (progressEl) {
    progressEl.textContent = `Progresso: ${current}/${total} (${percent}%)`;
  }

  if (etaEl) {
    etaEl.textContent = `ETA: ${eta}`;
  }

  if (barEl) {
    barEl.style.width = `${Math.max(0, Math.min(100, percent))}%`;
  }

  return { current, total, percent };
}

/* ============================================================
   FOTO — SCANSIONE
   ============================================================ */
async function scan() {
  startScanStatusPolling();

  try {
    await apiGet(`/scan`);
  } catch (err) {
    console.error("Errore avvio scan foto:", err);
    out?.({ error: err.message });
    stopScanPolling();
  }
}

function startScanStatusPolling() {
  stopScanPolling();

  scanInterval = setInterval(async () => {
    try {
      const data = await apiGet(`/scanStatus/photos?ts=${Date.now()}`);

      const { current, total } = updateScanUi(data);

      if (current >= total && total > 0) {
        stopScanPolling();

        if (window.AdminCacheSync?.progressiveSyncPhotosCacheFromAdmin) {
          const result = await AdminCacheSync.progressiveSyncPhotosCacheFromAdmin();
          console.log("[admin scan foto] cache aggiornata:", result);
        } else {
          console.warn("[admin scan foto] AdminCacheSync non disponibile");
        }

        await readDBUser();
      }
    } catch (err) {
      console.warn("[scan foto] lettura scan status fallita, riprovo:", err.message);
    }
  }, 1000);
}

/* ============================================================
   ATTIVITÀ — SCANSIONE
   ============================================================ */
async function scanActivities() {
  startScanActivitiesPolling();

  try {
    await apiGet(`/scanActivities`);
  } catch (err) {
    console.error("Errore avvio scan attività:", err);
    outActivities?.({ error: err.message });
    stopScanPolling();
  }
}

function startScanActivitiesPolling() {
  stopScanPolling();

  scanInterval = setInterval(async () => {
    try {
      const data = await apiGet(`/scanStatus/activities?ts=${Date.now()}`);

      const { current, total } = updateScanUi(data);

      if (current >= total && total > 0) {
        stopScanPolling();

        if (window.AdminCacheSync?.progressiveSyncActivitiesCacheFromAdmin) {
          const result = await AdminCacheSync.progressiveSyncActivitiesCacheFromAdmin();
          console.log("[admin scan attività] cache aggiornata:", result);
        } else {
          console.warn("[admin scan attività] AdminCacheSync non disponibile");
        }

        await readActivitiesDBUser();
      }
    } catch (err) {
      console.warn("[scan attività] lettura scan status fallita, riprovo:", err.message);
    }
  }, 1000);
}