import * as tldts from './cached-tld-parse'; import { isProbablyIpv4 } from './is-fast-ip'; export const normalizeDomain = (domain: string) => { if (!domain) return null; if (isProbablyIpv4(domain)) return null; const parsed = tldts.parse2(domain); if (parsed.isIp) return null; if (!parsed.isIcann && !parsed.isPrivate) return null; const h = parsed.hostname; if (!h) return null; return h[0] === '.' ? h.slice(1) : h; };