export interface EncryptionKey {
    key: CryptoKey;
    keyData: ArrayBuffer;
}
export interface EncryptionResult {
    encryptedData: ArrayBuffer;
    iv: ArrayBuffer;
}
/**
 * Generate a new AES-256-GCM encryption key
 */
declare function generateEncryptionKey(instanceId: string): Promise<EncryptionKey>;
/**
 * Encrypt data using AES-256-GCM
 */
declare function encryptData(data: ArrayBuffer, key: CryptoKey, instanceId: string): Promise<EncryptionResult>;
/**
 * Convert ArrayBuffer to Base64 string
 */
declare function arrayBufferToBase64(buffer: ArrayBuffer): string;
/**
 * Import AES-256-GCM encryption key from ArrayBuffer key data
 */
declare function importEncryptionKey(keyData: ArrayBuffer, instanceId: string): Promise<CryptoKey>;
/**
 * Decrypt data using AES-256-GCM
 */
declare function decryptData(encryptedData: ArrayBuffer, key: CryptoKey, iv: ArrayBuffer, instanceId: string): Promise<ArrayBuffer>;
export { arrayBufferToBase64, decryptData, encryptData, generateEncryptionKey, importEncryptionKey };