@polkadot/util-crypto/address/check.js

// Copyright 2017-2022 @polkadot/util-crypto authors & contributors
// SPDX-License-Identifier: Apache-2.0
import { base58Decode } from "../base58/index.js";
import { checkAddressChecksum } from "./checksum.js";
import { defaults } from "./defaults.js";
/**
 * @name checkAddress
 * @summary Validates an ss58 address.
 * @description
 * From the provided input, validate that the address is a valid input.
 */

export function checkAddress(address, prefix) {
  let decoded;

  try {
    decoded = base58Decode(address);
  } catch (error) {
    return [false, error.message];
  }

  const [isValid,,, ss58Decoded] = checkAddressChecksum(decoded);

  if (ss58Decoded !== prefix) {
    return [false, `Prefix mismatch, expected ${prefix}, found ${ss58Decoded}`];
  } else if (!defaults.allowedEncodedLengths.includes(decoded.length)) {
    return [false, 'Invalid decoded address length'];
  }

  return [isValid, isValid ? null : 'Invalid decoded address checksum'];
}