import { type Keypair } from "@solana/web3.js";
import type { CompactNoteCipher } from "../compactNote.js";
export declare const VEILO_VIEW_KEY_DOMAIN = "Veilo view key v1";
export declare const VEILO_VIEW_KEY_SALT = "veilo_view_x25519_v1";
export declare const VEILO_VIEW_KEY_INFO = "x25519";
export interface ViewKeypair {
    /** 32-byte clamped X25519 scalar. Secret: decrypts every v2 note sent to it. */
    viewSecretKey: Uint8Array;
    /** 32-byte X25519 public key. Safe to publish as the v2 encryption target. */
    viewPublicKey: Uint8Array;
}
/** Exact, human-readable bytes the wallet signs to grant view access. */
export declare function getViewKeyMessage(walletPublicKey: string, index?: number): Uint8Array;
/** Convert the view-domain signature into a root unrelated to spend authority. */
export declare function deriveViewRootFromSignature(signature: Uint8Array): Uint8Array;
/** Derive the X25519 keypair from a view-only root. */
export declare function deriveViewKeypairFromViewRoot(viewRoot: Uint8Array): ViewKeypair;
/**
 * Derive through wallet-standard `signMessage` and verify the wallet signed the
 * exact requested bytes. A prefixed/transformed signature fails loudly.
 */
export declare function deriveViewKeypairWithSigner(signMessage: (message: Uint8Array) => Promise<Uint8Array>, walletPublicKey: string, index?: number): Promise<ViewKeypair>;
/** Convenience for Veilo's first-party wallet and extension implementations. */
export declare function deriveViewKeypairFromKeypair(keypair: Keypair, index?: number): ViewKeypair;
/** Open one fixed-layout note encrypted to a v2 X25519 view public key. */
export declare function openCompactNoteWithViewKey(viewSecretKey: Uint8Array, cipher: CompactNoteCipher): {
    blinding: Uint8Array;
    amount: bigint;
} | null;