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import { _0n, BN, bnToU8a, hasBigInt, isU8a, nToU8a, u8aToBigInt } from 'https://deno.land/x/polkadot@0.2.40/util/mod.ts';import { BigInt } from 'https://deno.land/x/polkadot@0.2.40/x-bigint/mod.ts';
import { BN_BE_256_OPTS, BN_BE_OPTS } from '../bn.ts';
const N = 'ffffffff ffffffff ffffffff fffffffe baaedce6 af48a03b bfd25e8c d0364141'.replace(/ /g, '');const N_BI = BigInt(`0x${N}`);const N_BN = new BN(N, 'hex');
function addBi (seckey: Uint8Array, tweak: Uint8Array): Uint8Array {  let res = u8aToBigInt(tweak, BN_BE_OPTS);
  if (res >= N_BI) {    throw new Error('Tweak parameter is out of range');  }
  res += u8aToBigInt(seckey, BN_BE_OPTS);
  if (res >= N_BI) {    res -= N_BI;  }
  if (res === _0n) {    throw new Error('Invalid resulting private key');  }
  return nToU8a(res, BN_BE_256_OPTS);}
function addBn (seckey: Uint8Array, tweak: Uint8Array): Uint8Array {  const res = new BN(tweak);
  if (res.cmp(N_BN) >= 0) {    throw new Error('Tweak parameter is out of range');  }
  res.iadd(new BN(seckey));
  if (res.cmp(N_BN) >= 0) {    res.isub(N_BN);  }
  if (res.isZero()) {    throw new Error('Invalid resulting private key');  }
  return bnToU8a(res, BN_BE_256_OPTS);}
export function secp256k1PrivateKeyTweakAdd (seckey: Uint8Array, tweak: Uint8Array, onlyBn?: boolean): Uint8Array {  if (!isU8a(seckey) || seckey.length !== 32) {    throw new Error('Expected seckey to be an Uint8Array with length 32');  } else if (!isU8a(tweak) || tweak.length !== 32) {    throw new Error('Expected tweak to be an Uint8Array with length 32');  }
  return !hasBigInt || onlyBn    ? addBn(seckey, tweak)    : addBi(seckey, tweak);}