type PrivateKeyType = Uint8Array & {
  readonly __tag: "PrivateKey";
  readonly length: 32;
};

import * as PrivateKey from './primitives/PrivateKey/index.js';

// From hex string
const pk = PrivateKey.from("0xac0974bec39a17e36ba4a6b4d238ff944bacb478cbed5efcae784d7bf4f2ff80");

// From Uint8Array
const bytes = new Uint8Array(32);
const pk2 = PrivateKey.fromBytes(bytes);

const publicKey = PrivateKey.toPublicKey(pk);
console.log(publicKey.length); // 64 (uncompressed)

const address = PrivateKey.toAddress(pk);
// Returns 20-byte Ethereum address

import * as Hash from './primitives/Hash/index.js';

const message = new TextEncoder().encode("Hello, Ethereum!");
const hash = Hash.keccak256(message);

const signature = PrivateKey.sign(pk, hash);
// Returns { r, s, v } ECDSA signature

const hex = PrivateKey.toHex(pk);
// "0xac0974bec39a17e36ba4a6b4d238ff944bacb478cbed5efcae784d7bf4f2ff80"

// Direct method calls without wrappers
const publicKey = PrivateKey._toPublicKey.call(pk);
const address = PrivateKey._toAddress.call(pk);

PrivateKey (32 bytes)
    |
    v
secp256k1.getPublicKey()
    |
    v
PublicKey (64 bytes, uncompressed)
    |
    v
keccak256(publicKey)
    |
    v
last 20 bytes
    |
    v
Address (20 bytes)

import { Sign } from './primitives/PrivateKey/sign.js';
import { sign as secp256k1Sign } from './crypto/Secp256k1/sign.js';

const sign = Sign({ secp256k1Sign });
const sig = sign(pk, hash);

// Generate random key
const randomBytes = crypto.getRandomValues(new Uint8Array(32));
const pk = PrivateKey.fromBytes(randomBytes);

// Use the key
const signature = PrivateKey.sign(pk, hash);

// Clear key from memory when done
randomBytes.fill(0);

// Hardhat/Anvil default account #0
const pk = PrivateKey.from(
  "0xac0974bec39a17e36ba4a6b4d238ff944bacb478cbed5efcae784d7bf4f2ff80"
);

const address = PrivateKey.toAddress(pk);
// 0xf39Fd6e51aad88F6F4ce6aB8827279cffFb92266