import CryptoBase from './crypto-base';
import { DecryptedContent, DecryptedContentAndAttachments, DecryptParams, EncryptedContent } from './types';
export default class Crypto extends CryptoBase {
    signingPublicKey?: string;
    constructor({ signingPublicKey }?: {
        signingPublicKey?: string;
    });
    /**
     * Encrypt input with a unique keypair for each submission
     * @param encryptionPublicKey The base-64 encoded public key for encrypting.
     * @param msg The message to encrypt, will be stringified.
     * @param signingPrivateKey Optional. Must be a base-64 encoded private key. If given, will be used to signing the given msg param prior to encrypting.
     * @returns The encrypted basestring.
     */
    encrypt: (msg: any, encryptionPublicKey: string, signingPrivateKey?: string) => EncryptedContent;
    /**
     * Decrypts an encrypted submission and returns it.
     * @param formSecretKey The base-64 secret key of the form to decrypt with.
     * @param decryptParams The params containing encrypted content and information.
     * @param decryptParams.encryptedContent The encrypted content encoded with base-64.
     * @param decryptParams.version The version of the payload. Used to determine the decryption process to decrypt the content with.
     * @param decryptParams.verifiedContent Optional. The encrypted and signed verified content. If given, the signingPublicKey will be used to attempt to open the signed message.
     * @returns The decrypted content if successful. Else, null will be returned.
     * @throws {MissingPublicKeyError} if a public key is not provided when instantiating this class and is needed for verifying signed content.
     */
    decrypt: (formSecretKey: string, decryptParams: DecryptParams) => DecryptedContent | null;
    /**
     * Returns true if a pair of public & secret keys are associated with each other
     * @param publicKey The public key to verify against.
     * @param secretKey The private key to verify against.
     */
    valid: (publicKey: string, secretKey: string) => boolean;
    /**
     * Decrypts an encrypted submission, and also download and decrypt any attachments alongside it.
     * @param formSecretKey Secret key as a base-64 string
     * @param decryptParams The params containing encrypted content and information.
     * @returns A promise of the decrypted submission, including attachments (if any). Or else returns null if a decryption error decrypting any part of the submission.
     * @throws {MissingPublicKeyError} if a public key is not provided when instantiating this class and is needed for verifying signed content.
     */
    decryptWithAttachments: (formSecretKey: string, decryptParams: DecryptParams) => Promise<DecryptedContentAndAttachments | null>;
}