export type MezoId = `${string}.mezo`

// NOTE: This was copied from mezo-portal and is based on the validation from
// workers/passport-auth/src/utils/mezo-id.ts.

// Most of these are restrictions for an DNS hostname label (i.e., the part
// before/after `.` in a full hostname) as outlined in RFC1034
// (https://www.rfc-editor.org/rfc/rfc1034).
//
// A few addenda are made to ensure that nothing can sneak through that could
// look like an Ethereum or Bitcoin address.
export const DISALLOWED_MEZO_ID_PATTERNS: { pattern: RegExp; error: string }[] =
  [
    // RFC1034.
    { pattern: /^$/, error: "Must not be empty." },
    { pattern: /^.{16,}$/, error: "Must have 15 characters or fewer." },
    {
      pattern: /^[^A-Za-z]/,
      error: "Must start with one of the letters A-Z or a-z.",
    },
    {
      pattern: /[^A-Za-z0-9-]/,
      error:
        "Must only use letters or numbers (A-Z, a-z, or 0-9), or hyphen (-).",
    },
    { pattern: /-$/, error: "Must not end in a hyphen (-)." },
    // On-chain shenanigan avoidance.
    { pattern: /0x/i, error: "Must not contain 0x." },
    {
      pattern: /^(?:bc1|tb1|[a-z]pub|[a-z]priv)/i,
      error: "Must not start with a Bitcoin magic string.",
    },
    {
      pattern: /^m[0-9]+$/i,
      error: 'No "m" + "numeric string" prefixes.',
    },
  ]

export function validateMezoId(mezoId: string): string[] {
  if (!/\.mezo$/.test(mezoId)) {
    return ["Must end with '.mezo'."]
  }

  const mezoIdWithoutSuffix = mezoId.replace(/\.mezo$/, "")

  const errors = DISALLOWED_MEZO_ID_PATTERNS.flatMap(({ pattern, error }) =>
    pattern.test(mezoIdWithoutSuffix) ? [error] : [],
  )

  return errors
}