/**
 * Local device id helpers shared between the lifecycle tick and the
 * 6-digit pairing flow. Both need the same base64url-encoded 16-byte id
 * the native host expects in `Advertise` / `StartPairingServer`.
 */

const DEVICE_ID_KEY = "peach_device_id";

export async function getOrCreateLocalDeviceId(): Promise<string> {
  try {
    const stored = await chrome.storage.local.get(DEVICE_ID_KEY);
    const value = (stored as Record<string, string | undefined>)[DEVICE_ID_KEY];
    if (typeof value === "string" && value) return value;
  } catch {
    // fall through to generation
  }
  const random = crypto.getRandomValues(new Uint8Array(16));
  let binary = "";
  for (const byte of random) binary += String.fromCharCode(byte);
  const id = btoa(binary)
    .replace(/\+/g, "-")
    .replace(/\//g, "_")
    .replace(/=+$/g, "");
  try {
    await chrome.storage.local.set({ [DEVICE_ID_KEY]: id });
  } catch {
    // best-effort
  }
  return id;
}