Merkle Tree Whitelist

import { MerkleTree } from "merkletreejs";
import { keccak256, encodePacked, toHex } from "viem";

// Build the tree from whitelist addresses
const whitelist = [
  "0x1234...",
  "0x5678...",
  "0xabcd...",
];

const leaves = whitelist.map((addr) =>
  keccak256(encodePacked(["address"], [addr]))
);

const tree = new MerkleTree(leaves, keccak256, { sortPairs: true });
const root = tree.getHexRoot();

// Generate a proof for a specific address
const leaf = keccak256(encodePacked(["address"], ["0x1234..."]));
const proof = tree.getHexProof(leaf);

console.log("Root:", root);
console.log("Proof:", proof);

// Verify on-chain in your Solidity contract:
// bytes32 leaf = keccak256(abi.encodePacked(msg.sender));
// require(MerkleProof.verify(proof, root, leaf), "Not whitelisted");