import { TezosToolkit } from "@taquito/taquito";
import { InMemorySigner } from "@taquito/signer";
import { char2Bytes } from "@taquito/utils";
import type { Env, MintResult } from "../types/index.js";
import { BigNumber } from "bignumber.js";
interface NFTStorage {
next_token_id: BigNumber;
}
let tezosInstance: TezosToolkit | null = null;
/**
* Initialize and return a TezosToolkit instance with the minter signer
*/
export async function getTezos(env: Env): Promise<TezosToolkit> {
if (tezosInstance) {
return tezosInstance;
}
const Tezos = new TezosToolkit(env.TEZOS_RPC_URL);
const signer = await InMemorySigner.fromSecretKey(env.MINTER_PRIVATE_KEY);
Tezos.setProvider({ signer });
tezosInstance = Tezos;
return Tezos;
}
/**
* Get the next token ID from the NFT contract
*/
export async function getNextTokenId(env: Env): Promise<number> {
const Tezos = await getTezos(env);
const contract = await Tezos.contract.at(env.NFT_CONTRACT);
const storage = await contract.storage<NFTStorage>();
return storage.next_token_id.toNumber();
}
/**
* Mint an NFT to the recipient with the given metadata URI
*/
export async function mintNFT(
env: Env,
recipient: string,
metadataUri: string
): Promise<MintResult> {
const Tezos = await getTezos(env);
const contract = await Tezos.contract.at(env.NFT_CONTRACT);
// Get current token ID before minting
const storage = await contract.storage<NFTStorage>();
const tokenId = storage.next_token_id.toNumber();
// Convert metadata URI string to bytes (raw UTF-8, not packed)
// This is required for TZIP-12/TZIP-21 compliance
const metadataBytes = char2Bytes(metadataUri);
// Call mint entrypoint with bytes
const op = await contract.methodsObject
.mint({ recipient, metadata_uri: metadataBytes })
.send();
// Wait for confirmation
await op.confirmation(1);
return {
tokenId,
opHash: op.hash,
metadataUri,
};
}
/**
* Validate a Tezos address format
*/
export function isValidTezosAddress(address: string): boolean {
return /^(tz1|tz2|tz3|KT1)[1-9A-HJ-NP-Za-km-z]{33}$/.test(address);
}
