import type { Integer, UnixTimestamp } from '@naturalcycles/js-lib/types';
import type { Pipeline } from '@naturalcycles/nodejs-lib/stream';
import type { CommonDBCreateOptions } from '../db.model.js';
/**
 * Common interface for Key-Value database implementations.
 *
 * @experimental
 */
export interface CommonKeyValueDB {
    /**
     * Manifest of supported features.
     */
    support: CommonKeyValueDBSupport;
    /**
     * Check that DB connection is working properly.
     */
    ping: () => Promise<void>;
    /**
     * Will do like `create table ...` for mysql.
     * Caution! dropIfExists defaults to false. If set to true - will actually DROP the table!
     */
    createTable: (table: string, opt?: CommonDBCreateOptions) => Promise<void>;
    /**
     * Returns an array of tuples [key, value]. Not found values are not returned (no error is thrown).
     *
     * Currently it is NOT required to maintain the same order as input `ids`.
     */
    getByIds: (table: string, ids: string[]) => Promise<KeyValueDBTuple[]>;
    deleteByIds: (table: string, ids: string[]) => Promise<void>;
    saveBatch: (table: string, entries: KeyValueDBTuple[], opt?: CommonKeyValueDBSaveBatchOptions) => Promise<void>;
    streamIds: (table: string, limit?: number) => Pipeline<string>;
    streamValues: (table: string, limit?: number) => Pipeline<Buffer>;
    streamEntries: (table: string, limit?: number) => Pipeline<KeyValueDBTuple>;
    count: (table: string) => Promise<number>;
    /**
     * Perform a batch of Increment operations.
     * Given entries array, increment each key of it (1st index of the tuple) by the given amount (2nd index of the tuple).
     *
     * Example:
     * [
     *   ['key1', 2],
     *   ['key2', 3],
     * ]
     * would increment `key1` by 2, and `key2` by 3.
     *
     * Returns the entries array with tuples of the same structure, with updated numbers.
     *
     * @experimental
     */
    incrementBatch: (table: string, entries: IncrementTuple[]) => Promise<IncrementTuple[]>;
}
export type KeyValueDBTuple = [key: string, value: Buffer];
export type IncrementTuple = [key: string, value: Integer];
export interface CommonKeyValueDBSaveBatchOptions {
    /**
     * If set (and if it's implemented by the driver) - will set expiry TTL for each key of the batch.
     * E.g EXAT in Redis.
     */
    expireAt?: UnixTimestamp;
}
/**
 * Manifest of supported features.
 */
export interface CommonKeyValueDBSupport {
    count?: boolean;
    increment?: boolean;
}
export declare const commonKeyValueDBFullSupport: CommonKeyValueDBSupport;