import { clearConvKeyCache } from '@chat-app/shared/chat';

import { devLocalSecretStore } from './secretStore';

// Aggressively scrub local crypto + chat caches on sign-out (and on
// app-close if the user opted in). Preserves things that aren't sensitive
// and would be annoying to lose (theme, locale, install-id).
//
// We can't enumerate IndexedDB names without async + the indexedDB API,
// so we list the ones we know about explicitly. Adding a new local store
// later? Append to LOCAL_DBS.

const LOCAL_DBS = ['soundboard', 'message-cache', 'chatapp-attachments'];
const PRESERVE_LOCAL_STORAGE = new Set([
  'chatapp.theme',
  'chatapp.locale',
  'chatapp.installId',
  'chatapp.wipeOnClose.v1',
  'chatapp.autoLockMinutes.v1',
  'i18nextLng',
]);

export async function wipeLocalState(userId: string | null): Promise<void> {
  // 1. Per-conversation key cache (in-memory).
  try { clearConvKeyCache(); } catch { /* never throws but be defensive */ }

  // 2. Stronghold / secret-store: drop the user-priv blob for this user.
  if (userId) {
    try { await devLocalSecretStore.removeSecret('chatapp.userpriv.' + userId); }
    catch (err) { console.warn('[wipe] userpriv remove failed', err); }
  }

  // 3. localStorage — preserve only the explicit whitelist.
  try {
    const keysToDrop: string[] = [];
    for (let i = 0; i < window.localStorage.length; i++) {
      const k = window.localStorage.key(i);
      if (k && !PRESERVE_LOCAL_STORAGE.has(k)) keysToDrop.push(k);
    }
    for (const k of keysToDrop) window.localStorage.removeItem(k);
  } catch (err) { console.warn('[wipe] localStorage clear failed', err); }

  // 4. sessionStorage — always full.
  try { window.sessionStorage.clear(); } catch { /* ignored */ }

  // 5. IndexedDB — delete known databases. Resolves even when blocked so
  // we don't hang sign-out forever.
  await Promise.allSettled(LOCAL_DBS.map((name) => new Promise<void>((resolve) => {
    try {
      const req = window.indexedDB.deleteDatabase(name);
      req.onsuccess = () => resolve();
      req.onerror = () => resolve();
      req.onblocked = () => resolve();
    } catch { resolve(); }
  })));
}