import { ConfigService } from '@nestjs/config';
export declare class PublicApiCryptoService {
    private readonly key;
    private readonly iv;
    constructor(config: ConfigService);
    encrypt(value: unknown): string;
    decrypt<T = unknown>(payload: unknown): T;
    tryDecrypt(payload: unknown): unknown | null;
    private normalizePayload;
    extractPayloadValue(payload: unknown): unknown;
    private parseJsonIfPossible;
    private toBase64Url;
    private fromBase64Url;
    private extractIvAndCiphertext;
}