/**
 * Browser-local Woo credentials (prototype per-user routing).
 *
 * Stored in localStorage on this device only — never written to server Settings
 * via the device-creds path. Attached as X-Woo-Username / X-Woo-App-Password on
 * Woo-touching API calls. See PROTOTYPE.md.
 */

const LS_USER = 'slabuploader.woo.device.username';
const LS_PASS = 'slabuploader.woo.device.appPassword';

export const HEADER_WOO_USERNAME = 'X-Woo-Username';
export const HEADER_WOO_APP_PASSWORD = 'X-Woo-App-Password';

export interface DeviceWooCreds {
  username: string;
  appPassword: string;
}

function safeGet(key: string): string {
  try {
    return (localStorage.getItem(key) || '').trim();
  } catch {
    return '';
  }
}

function safeSet(key: string, value: string): void {
  try {
    if (value) localStorage.setItem(key, value);
    else localStorage.removeItem(key);
  } catch {
    /* private mode / quota — ignore */
  }
}

export function getDeviceWooCreds(): DeviceWooCreds {
  return {
    username: safeGet(LS_USER),
    appPassword: safeGet(LS_PASS),
  };
}

/** Persist this browser's Woo login. Empty strings clear the slot. */
export function setDeviceWooCreds(creds: DeviceWooCreds): void {
  safeSet(LS_USER, (creds.username || '').trim());
  safeSet(LS_PASS, (creds.appPassword || '').trim());
}

export function clearDeviceWooCreds(): void {
  safeSet(LS_USER, '');
  safeSet(LS_PASS, '');
}

/** Headers to merge into Woo-backed fetch calls. Empty object when unset. */
export function wooOverrideHeaders(): Record<string, string> {
  const { username, appPassword } = getDeviceWooCreds();
  if (!username || !appPassword) return {};
  return {
    [HEADER_WOO_USERNAME]: username,
    [HEADER_WOO_APP_PASSWORD]: appPassword,
  };
}

/** Merge Content-Type / caller headers with device Woo override when present. */
export function withWooHeaders(extra?: HeadersInit): HeadersInit {
  const woo = wooOverrideHeaders();
  if (!extra) return woo;
  if (extra instanceof Headers) {
    const h = new Headers(extra);
    for (const [k, v] of Object.entries(woo)) h.set(k, v);
    return h;
  }
  if (Array.isArray(extra)) {
    return [...extra, ...Object.entries(woo)];
  }
  return { ...extra, ...woo };
}

/** True when this browser has both device Woo username and app password. */
export function hasDeviceWooCreds(): boolean {
  const { username, appPassword } = getDeviceWooCreds();
  return Boolean(username && appPassword);
}