import { useEffect, useSyncExternalStore } from 'react';
import {
  dismissNotice,
  getNoticesState,
  isClosed,
  startNoticePolling,
  subscribeNotices,
  visibleNotices,
  type Notice,
} from '../api/notices';

/** The notices in force for this app. Reading is free; polling starts with `poll`. */
export function usePlatformNotices({ poll = false }: { poll?: boolean } = {}) {
  const state = useSyncExternalStore(subscribeNotices, getNoticesState);

  useEffect(() => (poll ? startNoticePolling() : undefined), [poll]);

  const notices = visibleNotices(state.notices, state.dismissed);
  return {
    notices,
    mode: state.mode,
    closedNotice: state.notices.find((n) => isClosed(n.mode)),
    dismiss: (n: Notice) => dismissNotice(n),
  };
}