/** Note data stored inside a Blind Mailbox encrypted blob */
export type BlindMailboxNoteData = {
    blinding: Uint8Array;
    leafIndex: number;
    commitment: Uint8Array;
    amount: bigint;
    mintAddress: string;
    treeId: number;
};
/** Encrypted note as returned by the relayer's /api/notes endpoint */
export type BlindMailboxNote = {
    commitment: string;
    ephemeralPublicKey: string;
    encryptedBlob: string;
    timestamp?: number;
    blockHeight?: number;
    txSignature?: string;
};
/** Decrypted note data after calling decryptBlindMailboxNote */
export type DecryptedNote = {
    blinding: Uint8Array;
    leafIndex: number;
    commitment: Uint8Array;
    amount: bigint;
    timestamp: number;
    mintAddress?: string;
    treeId: number;
};
/** Derive 32-byte encryption key from a shared secret using SHA-512 truncated.
 *  Must match the production "sha256" helper which uses nacl.hash (SHA-512) [0:32].
 *
 *  DO NOT "fix" this to real SHA-256. The name in the sibling implementations
 *  (`sha256ForNotes`) is a misnomer, but the bytes are load-bearing: changing the
 *  KDF makes every historical note undecryptable.
 *
 *  @internal Exported for `compactNote.ts`. Not part of the stable public API. */
export declare function kdfSHA512_256(secret: Uint8Array): Uint8Array;
/** Convert an Ed25519 private seed (32 bytes) to an X25519 scalar.
 *  Equivalent to ed2curve.convertSecretKey(seed).
 *
 *  @internal Exported for `compactNote.ts`. Not part of the stable public API. */
export declare function ed25519SeedToX25519Private(seed: Uint8Array): Uint8Array;
/** Convert an Ed25519 compressed public key (32 bytes) to X25519.
 *  Equivalent to ed2curve.convertPublicKey(pubkey).
 *  Edwards y-coord → Montgomery u via: u = (1 + y) / (1 - y) (mod p).
 *
 *  @internal Exported for `compactNote.ts`. Not part of the stable public API. */
export declare function ed25519PublicKeyToX25519(pubkey: Uint8Array): Uint8Array;
/**
 * Encrypt a UTXO note for a recipient identified by their Solana wallet public key.
 * Produces a blob the relayer will store and serve via POST /notes/save.
 *
 * @param recipientWalletPubkey  32-byte Ed25519 public key (wallet.publicKey.toBytes())
 * @param noteData               UTXO details to encrypt
 */
export declare function encryptBlindMailboxNote(recipientWalletPubkey: Uint8Array, noteData: BlindMailboxNoteData): {
    ephemeralPublicKey: Uint8Array;
    encryptedBlob: string;
};
/**
 * Decrypt a Blind Mailbox note using the recipient's Solana wallet private seed.
 *
 * @param walletSecretKey  Full 64-byte wallet.secretKey — the first 32 bytes are the seed
 * @param ephemeralPublicKey  32-byte raw public key stored alongside the encrypted blob.
 *                            This may be either an Ed25519 pubkey (from Keypair.generate())
 *                            or a raw X25519 pubkey — the decryption path handles both:
 *                            if it is an Ed25519 key it is converted; otherwise used directly.
 * @param encryptedBlob      Base64 string as stored by the relayer
 */
export declare function decryptBlindMailboxNote(walletSecretKey: Uint8Array, ephemeralPublicKey: Uint8Array, encryptedBlob: string): DecryptedNote;