import { Parts, RandomBytes } from './GF256';
/**
 * Splits the given secret into {@code n} parts, of which any {@code k} or more can be combined to
 * recover the original secret.
 * @param  {(number) => Uint8Array} randomBytes Takes a length and returns a random
 * Uint8Array of that length
 * @param  {number} n the number of parts to produce (must be `>1`)
 * @param  {number} k the threshold of joinable parts (must be `<= n`})
 * @param  {Uint8Array} secret The secret to split as an array of bytes
 * @return {Parts} an map of `n` parts that are arrays of bytes of the
 * secret length
 */
export declare function split(randomBytes: RandomBytes, n: number, k: number, secret: Uint8Array): Parts;
/**
 * Joins the given parts to recover the original secret.
 *
 * <p><b>N.B.:</b> There is no way to determine whether or not the returned value is actually the
 * original secret. If the parts are incorrect, or are under the threshold value used to split the
 * secret, a random value will be returned.
 *
 * @param {Parts} parts an map of {@code n} parts that are arrays of bytes
 * of the secret length
 * @return {Uint8Array} the original secret
 *
 */
export declare function join(parts: Parts): Uint8Array;
/**
 * Restores a part given a map of parts and a new index.
 *
 * @param {Parts} parts a map of part IDs to part values
 * @param {number} partIdx the new index for the part
 * @return {Uint8Array} the restored part
 * @throws {Error} if parts is empty or contains values of varying lengths
 */
export declare function restorePart(parts: Parts, partIdx: number): Uint8Array;