import { MatrixClient, NotificationCountType, ReceiptType, Room } from 'matrix-js-sdk';

/**
 * [Gitea #165] Send a threaded read receipt for every thread in the room that
 * has unread replies. Mirrors the per-thread half of `markAsRead`, including
 * its rule: never fall back to the thread root (a root lives in the main
 * timeline, so a receipt there would move the MAIN read marker backwards).
 * Returns how many threads were marked.
 */
export async function markAllThreadsRead(
  mx: MatrixClient,
  room: Room,
  privateReceipt: boolean,
): Promise<number> {
  const receiptType = privateReceipt ? ReceiptType.ReadPrivate : ReceiptType.Read;
  const sends = room
    .getThreads()
    .map((thread) => {
      const unread =
        room.getThreadUnreadNotificationCount(thread.id, NotificationCountType.Total) ?? 0;
      if (unread <= 0) return undefined;
      const lastReply = thread.lastReply();
      if (!lastReply || lastReply.isSending()) return undefined;
      return mx.sendReadReceipt(lastReply, receiptType, false).catch(() => undefined);
    })
    .filter((p): p is NonNullable<typeof p> => !!p);
  await Promise.all(sends);
  return sends.length;
}