/**
 * NIP-19: bech32-encoded entities
 * @module nip19
 * @description Implements NIP-19 specification for bech32-encoded entities in Nostr.
 * Provides encoding and decoding functions for npub (public keys), nsec (private keys),
 * and note (event IDs) formats.
 * @see https://github.com/nostr-protocol/nips/blob/master/19.md
 */
type Nip19DataType = "npub" | "nsec" | "note" | "nprofile" | "nevent" | "naddr" | "nrelay";
/**
 * Encodes a public key into npub format
 * @param {string} hex - The hex-encoded public key
 * @returns {string} The bech32-encoded npub string
 * @throws {Error} If encoding fails
 * @example
 * const npub = hexToNpub('3bf0c63fcb93463407af97a5e5ee64fa883d107ef9e558472c4eb9aaaefa459d');
 * returns 'npub1...'
 */
export declare function hexToNpub(hex: string): string;
/**
 * Encodes a private key into nsec format
 * @param {string} hex - The hex-encoded private key
 * @returns {string} The bech32-encoded nsec string
 * @throws {Error} If encoding fails
 * @security This function handles sensitive private key data
 * @example
 * const nsec = hexToNsec('3bf0c63fcb93463407af97a5e5ee64fa883d107ef9e558472c4eb9aaaefa459d');
 * returns 'nsec1...'
 */
export declare function hexToNsec(hex: string): string;
/**
 * Encodes an event ID into note format
 * @param {string} hex - The hex-encoded event ID
 * @returns {string} The bech32-encoded note string
 * @throws {Error} If encoding fails
 * @example
 * const note = hexToNote('3bf0c63fcb93463407af97a5e5ee64fa883d107ef9e558472c4eb9aaaefa459d');
 * returns 'note1...'
 */
export declare function hexToNote(hex: string): string;
/**
 * Decodes a bech32-encoded Nostr entity
 * @param {string} str - The bech32-encoded string (npub1, nsec1, or note1)
 * @returns {Nip19Data} Object containing the decoded type and data
 * @throws {Error} If decoding fails
 * @example
 * const result = decode('npub1...');
 * returns { type: 'npub', data: '...' }
 */
export declare function decode(str: string): {
    type: Nip19DataType;
    data: string;
};
/**
 * Converts a bech32 nsec private key to hex format
 * @param {string} nsec - The bech32-encoded nsec private key
 * @returns {string} The hex-encoded private key
 * @throws {Error} If conversion fails or input is invalid
 * @security This function handles sensitive private key data
 * @example
 * const hex = nsecToHex('nsec1...');
 * returns '3bf0c63f...'
 */
export declare function nsecToHex(nsec: string): string;
/**
 * Converts a bech32 npub public key to hex format
 * @param {string} npub - The bech32-encoded npub public key
 * @returns {string} The hex-encoded public key
 * @throws {Error} If conversion fails or input is invalid
 * @example
 * const hex = npubToHex('npub1...');
 * returns '3bf0c63f...'
 */
export declare function npubToHex(npub: string): string;
export {};