SukkaSurge/Build/lib/normalize-domain.ts

// https://github.com/remusao/tldts/issues/2121
// In short, single label domain suffix is ignored due to the size optimization, so no isIcann
// import tldts from 'tldts-experimental';
import tldts from 'tldts';
import { normalizeTldtsOpt } from '../constants/loose-tldts-opt';
import { isProbablyIpv4, isProbablyIpv6 } from 'foxts/is-probably-ip';

export type TldTsParsed = ReturnType<typeof tldts.parse>;

/**
 * Skipped the input non-empty check, the `domain` should not be empty.
 */
function fastNormalizeDomainWithoutWwwNoIP(domain: string, parsed: TldTsParsed | null = null) {
  // We don't want tldts to call its own "extractHostname" on ip, bail out ip first.
  // This function won't run with IP, we can safely set normalizeTldtsOpt.detectIp to false.

  parsed ??= tldts.parse(domain, normalizeTldtsOpt);
  // Private invalid domain (things like .tor, .dn42, etc)
  if (!parsed.isIcann && !parsed.isPrivate) return null;

  if (parsed.subdomain) {
    if (
      parsed.subdomain === 'www'
      || parsed.subdomain === 'xml-v4'
      || parsed.subdomain === 'xml-eu'
      || parsed.subdomain === 'xml-eu-v4'
      // || (parsed.subdomain.length === 4 && parsed.subdomain.startsWith('www'))
    ) {
      return parsed.domain;
    }
    if (parsed.subdomain.startsWith('www.')) {
      return parsed.subdomain.slice(4) + '.' + parsed.domain;
    }
  }

  return parsed.hostname;
}

/**
 * Skipped the input non-empty check, the `domain` should not be empty.
 */
export function fastNormalizeDomainWithoutWww(domain: string, parsed: TldTsParsed | null = null) {
  // We don't want tldts to call its own "extractHostname" on ip, bail out ip first.
  // Now ip has been bailed out, we can safely set normalizeTldtsOpt.detectIp to false.
  if (isProbablyIpv4(domain) || isProbablyIpv6(domain)) {
    return null;
  }

  return fastNormalizeDomainWithoutWwwNoIP(domain, parsed);
}

/**
 * Skipped the input non-empty check, the `domain` should not be empty.
 */
export function fastNormalizeDomain(domain: string, parsed: TldTsParsed | null = null) {
  // We don't want tldts to call its own "extractHostname" on ip, bail out ip first.
  // Now ip has been bailed out, we can safely set normalizeTldtsOpt.detectIp to false.
  if (isProbablyIpv4(domain) || isProbablyIpv6(domain)) {
    return null;
  }

  parsed ??= tldts.parse(domain, normalizeTldtsOpt);
  // Private invalid domain (things like .tor, .dn42, etc)
  if (!parsed.isIcann && !parsed.isPrivate) return null;

  return parsed.hostname;
}

export function normalizeDomain(domain: string, parsed: TldTsParsed | null = null) {
  if (domain.length === 0) return null;

  if (isProbablyIpv4(domain) || isProbablyIpv6(domain)) {
    return null;
  }

  parsed ??= tldts.parse(domain, normalizeTldtsOpt);
  // Private invalid domain (things like .tor, .dn42, etc)
  if (!parsed.isIcann && !parsed.isPrivate) return null;

  // const h = parsed.hostname;
  // if (h === null) return null;

  return parsed.hostname;
}