import { BinaryBlob } from '@dfinity/candid';
import { PublicKey, SignIdentity } from '@dfinity/agent';
import Secp256k1PublicKey from './publicKey';
declare type PublicKeyHex = string;
declare type SecretKeyHex = string;
export declare type JsonableSecp256k1Identity = [PublicKeyHex, SecretKeyHex];
declare class Secp256k1KeyIdentity extends SignIdentity {
    protected _privateKey: BinaryBlob;
    static fromParsedJson(obj: [string, string]): Secp256k1KeyIdentity;
    static fromJSON(json: string): Secp256k1KeyIdentity;
    static fromKeyPair(publicKey: BinaryBlob, privateKey: BinaryBlob): Secp256k1KeyIdentity;
    static fromSecretKey(secretKey: ArrayBuffer): Secp256k1KeyIdentity;
    protected _publicKey: Secp256k1PublicKey;
    protected constructor(publicKey: PublicKey, _privateKey: BinaryBlob);
    /**
     * Serialize this key to JSON.
     */
    toJSON(): JsonableSecp256k1Identity;
    /**
     * Return a copy of the key pair.
     */
    getKeyPair(): {
        secretKey: BinaryBlob;
        publicKey: Secp256k1PublicKey;
    };
    /**
     * Return the public key.
     */
    getPublicKey(): PublicKey;
    /**
     *  Return private key in a pem file
     */
    getPem(): string;
    /**
     * Signs a blob of data, with this identity's private key.
     * @param challenge - challenge to sign with this identity's secretKey, producing a signature
     */
    sign(challenge: BinaryBlob): Promise<BinaryBlob>;
}
export default Secp256k1KeyIdentity;