/**
 * @typedef {Object} FingerprintOptions
 * @property {boolean} [includeIP=false]
 * @property {boolean} [subnet=false]
 * @property {boolean} [strict=true]
 * @property {string} [algorithm='sha256']
 */
/**
 * @typedef {Object} FingerprintInput
 * @property {string} [ua]
 * @property {Record<string, string>} [headers]
 * @property {string} [ip]
 */
/**
 * Create a deterministic fingerprint from request signals.
 *
 * Layers:
 * - **Stable** (always included): browser family, OS family, device type
 * - **Semi-stable** (included unless `strict: false`): browser major, OS version, Accept-Language
 * - **Volatile** (opt-in): IP subnet
 *
 *   import { createFingerprint } from '@exortek/ua/fingerprint';
 *
 *   const fp = createFingerprint({
 *     ua: req.headers['user-agent'],
 *     headers: req.headers,
 *     ip: req.ip,
 *   });
 *   // → 'fp_a8f3b2c1d4e5f6...'
 *
 * @param {FingerprintInput} input
 * @param {FingerprintOptions} [options]
 * @returns {string}
 */
declare function createFingerprint(input: FingerprintInput, options?: FingerprintOptions): string;
/**
 * Create a fingerprint from a request object (Express/Fastify compatible).
 *
 *   import { fingerprintRequest } from '@exortek/ua/fingerprint';
 *
 *   app.use((req, res, next) => {
 *     req.fingerprint = fingerprintRequest(req);
 *     next();
 *   });
 *
 * @param {Object} req
 * @param {FingerprintOptions} [options]
 * @returns {string}
 */
declare function fingerprintRequest(req: Object, options?: FingerprintOptions): string;
type FingerprintOptions = {
    includeIP?: boolean | undefined;
    subnet?: boolean | undefined;
    strict?: boolean | undefined;
    algorithm?: string | undefined;
};
type FingerprintInput = {
    ua?: string | undefined;
    headers?: Record<string, string> | undefined;
    ip?: string | undefined;
};

export { createFingerprint, fingerprintRequest };
export type { FingerprintInput, FingerprintOptions };