/**
 * Provides platform-agnostic cryptographic utility functions.
 *
 * @remarks
 * This module contains utility functions for cryptographic operations that work
 * consistently across Node.js and browser environments. All functions use `Uint8Array`
 * exclusively for binary data to ensure cross-platform compatibility.
 *
 * @category Cryptography
 */
/**
 * Processes a wallet public key for cryptographic operations.
 *
 * @remarks
 * Converts hex string public keys to Uint8Array format.
 * For normalization to uncompressed format, use the crypto provider's
 * normalizeToUncompressed method.
 *
 * @param publicKey - The wallet public key as hex string or byte array.
 * @returns The public key as a Uint8Array.
 *
 * @example
 * ```typescript
 * const keyBytes = processWalletPublicKey("0x04...");
 * const normalized = provider.normalizeToUncompressed(keyBytes);
 * ```
 */
export declare function processWalletPublicKey(publicKey: string | Uint8Array): Uint8Array;
/**
 * Processes a wallet private key for cryptographic operations.
 *
 * @param privateKey - The wallet private key as hex string or byte array.
 * @returns The private key as a Uint8Array.
 *
 * @example
 * ```typescript
 * const key = processWalletPrivateKey("0x...");
 * console.log(key.length); // 32 (secp256k1 private key)
 * ```
 */
export declare function processWalletPrivateKey(privateKey: string | Uint8Array): Uint8Array;
/**
 * Parses legacy eccrypto-format encrypted data buffer.
 * Format: [iv(16)][ephemPublicKey(65)][ciphertext(variable)][mac(32)]
 *
 * @param encryptedBuffer - Buffer containing encrypted data in eccrypto format
 * @returns Parsed encrypted data components
 */
export declare function parseEncryptedDataBuffer(encryptedBuffer: Uint8Array): {
    iv: Uint8Array;
    ephemPublicKey: Uint8Array;
    ciphertext: Uint8Array;
    mac: Uint8Array;
};
/**
 * Generates a deterministic seed from a message for key derivation
 *
 * @param message - Message to derive seed from
 * @returns Seed as Uint8Array
 */
export declare function generateSeed(message: string): Uint8Array;
/**
 * Compares two Uint8Arrays for equality
 *
 * @param a - First array
 * @param b - Second array
 * @returns True if arrays are equal
 */
export declare function bytesEqual(a: Uint8Array, b: Uint8Array): boolean;
/**
 * Creates a copy of a Uint8Array
 *
 * @param bytes - Array to copy
 * @returns New array with same contents
 */
export declare function copyBytes(bytes: Uint8Array): Uint8Array;
/**
 * Validates a secp256k1 public key format
 *
 * @param publicKey - Public key to validate
 * @returns True if valid format (33, 65, or 64 bytes)
 */
export declare function isValidPublicKeyFormat(publicKey: Uint8Array): boolean;
/**
 * Validates a secp256k1 private key format
 *
 * @param privateKey - Private key to validate
 * @returns True if valid format (32 bytes)
 */
export declare function isValidPrivateKeyFormat(privateKey: Uint8Array): boolean;
/**
 * Asserts that a public key is in uncompressed format (65 bytes with 0x04 prefix).
 * This validation function only checks format, it does not transform keys.
 * For key normalization (including decompression), use the crypto provider's
 * normalizeToUncompressed method.
 *
 * @param publicKey - Public key to validate
 * @throws {Error} When public key is not in uncompressed format
 */
export declare function assertUncompressedPublicKey(publicKey: Uint8Array): void;