import { MaybePromise, Peer } from '@mtcute/core';
import { BusinessMessageContext } from '../context/business-message.js';
import { CallbackQueryContext, MessageContext } from '../context/index.js';
/**
 * Function that determines how the state key is derived.
 *
 * The key is additionally prefixed with current scene, if any.
 *
 * @param msg  Message or callback from which to derive the key
 * @param scene  Current scene UID, or `null` if none
 */
export type StateKeyDelegate = (upd: MessageContext | BusinessMessageContext | CallbackQueryContext | Peer) => MaybePromise<string | null>;
/**
 * Default state key delegate.
 *
 * Derives key as follows:
 *  - If private chat, `msg.chat.id`
 *  - If group chat, `msg.chat.id + '_' + msg.sender.id`
 *  - If channel, `msg.chat.id`
 *  - If non-inline callback query:
 *    - If in private chat (i.e. `upd.chatType === 'user'`), `upd.user.id`
 *    - If in group/channel/supergroup (i.e. `upd.chatType !== 'user'`), `upd.chatId + '_' + upd.user.id`
 */
export declare const defaultStateKeyDelegate: StateKeyDelegate;