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import { randomBytes } from "@/worker/auth/bytes";
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import { HOST_WORDS } from "@/worker/auth/host-wordlist";
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const wordSet = new Set<string>(HOST_WORDS);
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const hostLabelRe = /^[a-z]+(-[a-z]+){4}$/;
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function randomWordIndex(): number {
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  const length = HOST_WORDS.length;
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  const max = 65_536 - (65_536 % length);
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  while (true) {
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    const bytes = randomBytes(2);
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    const value = (bytes[0] << 8) | bytes[1];
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    if (value < max) return value % length;
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  }
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}
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export function isValidHostLabel(label: string): boolean {
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  if (label.length > 63 || !hostLabelRe.test(label)) return false;
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  return label.split("-").every((word) => wordSet.has(word));
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}
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export function generateHostLabel(): string {
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  for (let attempt = 0; attempt < 100; attempt += 1) {
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    const words = Array.from({ length: 5 }, () => HOST_WORDS[randomWordIndex()]);
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    const label = words.join("-");
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    if (label.length <= 63) return label;
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  }
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  throw new Error("Unable to generate a host label under 64 characters");
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}