import { PublicKey } from "@solana/web3.js";
/**
 * Keypair for UTXO ownership.
 * Public key is derived via Poseidon: pubkey = Poseidon(privateKey)
 */
export type Keypair = {
    privateKey: bigint;
    publicKey: bigint;
};
/**
 * UTXO structure matching the circuit's UTXOCommitment template.
 * commitment = Poseidon(amount, pubkey, blinding, mintAddress)
 */
export type UTXO = {
    /** Amount in lamports/token units */
    amount: bigint;
    /** Owner's public key (derived from private key via Poseidon) */
    pubkey: bigint;
    /** Random blinding factor for commitment privacy */
    blinding: bigint;
    /** Token mint address as field element */
    mintAddress: bigint;
};
/**
 * Serialized UTXO with precomputed commitment and optional ownership data.
 */
export type SerializedUTXO = UTXO & {
    /** 32-byte commitment: Poseidon(amount, pubkey, blinding, mintAddress) */
    commitment: Uint8Array;
    /** Private key for spending (only present for owned UTXOs) */
    privateKey?: bigint;
    /** Leaf index in the Merkle tree (set after insertion) */
    pathIndex?: number;
};
/**
 * Input UTXO with Merkle proof data for spending.
 */
export type InputUTXO = SerializedUTXO & {
    /** Leaf index in the Merkle tree */
    pathIndex: number;
    /** Merkle path elements (sibling hashes from leaf to root) */
    pathElements: Uint8Array[];
    /** Private key for nullifier derivation */
    privateKey: bigint;
};
/**
 * Generate a random keypair.
 * Private key is a random 32-byte scalar.
 * Public key is derived via Poseidon: pubkey = Poseidon(privateKey)
 */
export declare function generateKeypair(): Keypair;
/**
 * Derive public key from private key.
 * Matches circuit's Keypair template: publicKey = Poseidon(privateKey)
 */
export declare function derivePublicKey(privateKey: bigint): bigint;
/**
 * Create keypair from a known private key.
 */
export declare function keypairFromPrivateKey(privateKey: bigint): Keypair;
/**
 * Compute UTXO commitment.
 * Matches circuit's UTXOCommitment template:
 *   commitment = Poseidon(amount, pubkey, blinding, mintAddress)
 */
export declare function commitUTXO(utxo: UTXO): Uint8Array;
/**
 * Create a random UTXO with the given parameters.
 */
export declare function createUTXO(params: {
    amount: bigint;
    pubkey: bigint;
    mintAddress: PublicKey;
}): SerializedUTXO;
/**
 * Create a UTXO with a specified private key (for owned UTXOs).
 */
export declare function createOwnedUTXO(params: {
    amount: bigint;
    privateKey: bigint;
    mintAddress: PublicKey;
}): SerializedUTXO;
/**
 * Create a zero UTXO (for deposits where no input exists).
 * Zero UTXOs have amount=0 and are used as placeholders in 2-in-2-out transactions.
 */
export declare function createZeroUTXO(pubkey: bigint, mintAddress: PublicKey): SerializedUTXO;
/**
 * Create a zero UTXO with private key (for owned zero UTXOs).
 */
export declare function createOwnedZeroUTXO(privateKey: bigint, mintAddress: PublicKey): SerializedUTXO;