import { DER, OctetEC, PEM, KeyFormat, CurveTypes, KeyExportOptions, JwkThumbprintFormat, HashTypes } from './typedef';
/**
 * Key class to abstract public and private key objects in string or binary.
 *   This class provides functions to interchangeably convert key formats,
 *   and key objects will be used for the root package, js-crypto-utils, as inputs to exposed APIs.
 */
export declare class Key {
    private _type;
    private _jwk;
    private _der;
    private _oct;
    private _isEncrypted;
    private _current;
    /**
     * @constructor
     * @param {KeyFormat} format - Key format: 'jwk', 'der', 'pem' or 'oct' (only for ECC key).
     * @param {JsonWebKey|PEM|DER|OctetEC} key - Key object in the specified format.
     * @param {Object} [options={}] - Required if format='oct', and then it is {namedCurve: String}.
     * @throws {Error} - Throws if the input format and key are incompatible to the constructor.
     */
    constructor(format: KeyFormat, key: JsonWebKey | PEM | DER | OctetEC, options?: {
        namedCurve?: CurveTypes;
    });
    /**
     * Set a key in JWK to the Key object.
     * @param {JsonWebKey} jwkey - The Json Web Key.
     * @private
     */
    private _setJwk;
    /**
     * Set a key in DER or PEM to the Key object.
     * @param {DER|PEM} asn1key - The DER key byte array or PEM key string.
     * @param {String} format - 'der' or 'pem' specifying the format.
     * @private
     */
    private _setAsn1;
    /**
     * Set a key in SEC1 = Octet format to the Key Object.
     * @param {OctetEC} sec1key - The Octet SEC1 key byte array.
     * @param {CurveTypes} namedCurve - Name of curve like 'P-256'.
     * @private
     */
    private _setSec1;
    /**
     * Set the current internal status. In particular, manage what the object is based on.
     * @private
     */
    private _setCurrentStatus;
    /**
     * Convert the stored key and export the key in desired format.
     * Imported key must be basically decrypted except the case where the key is exported as-is.
     * @param {String} format - Intended format of exported key. 'jwk', 'pem', 'der' or 'oct'
     * @param {KeyExportOptions} [options={}] - Optional arguments.
     * @return {Promise<JsonWebKey|PEM|DER|OctetEC>} - Exported key object.
     */
    export(format?: KeyFormat, options?: KeyExportOptions): Promise<JsonWebKey | PEM | DER | OctetEC>;
    /**
     * Encrypt stored key and set the encrypted key to this instance.
     * @param {String} passphrase - String passphrase.
     * @return {Promise<boolean>} - Always true otherwise thrown.
     * @throws {Error} - Throws if AlreadyEncrypted.
     */
    encrypt(passphrase: string): Promise<boolean>;
    /**
     * Decrypted stored key and set the decrypted key in JWK to this instance.
     * @param {String} passphrase - String passphrase.
     * @return {Promise<boolean>} - Always true otherwise thrown.
     * @throws {Error} - Throws if NotEncrypted or FailedToDecrypt.
     */
    decrypt(passphrase: string): Promise<boolean>;
    /**
     * Conpute JWK thumbprint specified in RFC7638 {@link https://tools.ietf.org/html/rfc7638}.
     * @param {HashTypes} [alg='SHA-256'] - Name of hash algorithm for thumbprint computation like 'SHA-256'.
     * @param {JwkThumbpirntFormat} [output='binary'] - Output format of JWK thumbprint. 'binary', 'hex' or 'base64'.
     * @return {Promise<Uint8Array|String>} - Computed thumbprint.
     * @throws {Error} - Throws if DecryptionRequired.
     */
    getJwkThumbprint(alg?: HashTypes, output?: JwkThumbprintFormat): Promise<string | Uint8Array>;
    /**
     * Get keyType in JWK format
     * @return {Promise<String>} - 'RSA' or 'EC'
     * @throws {Error} - Throws if DecryptionRequired.
     */
    get keyType(): Promise<string>;
    /**
     * Get jwkThumbprint of this key.
     * @return {Promise<Uint8Array>} - Returns binary thumbprint.
     */
    get jwkThumbprint(): Promise<string | Uint8Array>;
    /**
     * Check if this is encrypted.
     * @return {boolean}
     */
    get isEncrypted(): boolean;
    /**
     * Check if this is a private key.
     * @return {boolean}
     */
    get isPrivate(): boolean;
    /**
     * Returns the key in DER format.
     * @return {Promise<DER>}
     */
    get der(): Promise<OctetEC | JsonWebKey>;
    /**
     * Returns the key in PEM format.
     * @return {Promise<PEM>}
     */
    get pem(): Promise<OctetEC | JsonWebKey>;
    /**
     * Returns the key in JWK format
     * @return {Promise<JsonWebKey>}
     */
    get jwk(): Promise<OctetEC | JsonWebKey>;
    /**
     * Returns the 'EC' key in Octet SEC1 format.
     * @return {Promise<OctetEC>}
     */
    get oct(): Promise<OctetEC | JsonWebKey>;
}