/**
 * LocalSecret Formatter
 *
 * Formats LocalSecrets for human-readable display and parses them back.
 * Uses an unambiguous character set (no 0, 1, I, O) for easy transcription.
 *
 * Format: A7K2M9-X4P8N3-B5J1L6-Q9W2R8-T3Y7U0-V6Z4C1-...
 *
 * Issue #1649
 */
import type { FormattedLocalSecret } from "./types";
/**
 * Format a LocalSecret for human-readable display
 *
 * @param secret - The 32-byte LocalSecret
 * @returns Formatted LocalSecret with grouped characters
 */
export declare function formatLocalSecret(secret: Uint8Array): FormattedLocalSecret;
/**
 * Parse a formatted LocalSecret back to bytes
 *
 * Handles various input formats:
 * - With dashes: A7K2M9-X4P8N3-...
 * - Without dashes: A7K2M9X4P8N3...
 * - With spaces: A7K2M9 X4P8N3 ...
 * - Lowercase: a7k2m9-x4p8n3-...
 *
 * @param formatted - The formatted LocalSecret string
 * @returns The 32-byte LocalSecret
 */
export declare function parseLocalSecret(formatted: string): Uint8Array;
/**
 * Validate a formatted LocalSecret string
 *
 * @param formatted - The formatted LocalSecret string
 * @returns true if valid, false otherwise
 */
export declare function isValidFormattedLocalSecret(formatted: string): boolean;
/**
 * Mask a LocalSecret for partial display
 *
 * Shows only the first and last groups, masking the middle.
 * Example: A7K2M9-******-******-******-******-V6Z4C1
 *
 * @param formatted - The formatted LocalSecret
 * @returns Masked version for display
 */
export declare function maskLocalSecret(formatted: string): string;