val result = Buffer()

    while (pos < limit) {
      var dot = string.indexOf('.', startIndex = pos)
      if (dot == -1) dot = limit

      if (!encodeLabel(string, pos, dot, result)) {
        // If we couldn't encode the label, give up.
        return null
      }

      if (dot < limit) {
        result.writeByte('.'.code)
        pos = dot + 1
      } else {
        break
      }
    }

    val result = Buffer()
    val dot = '.'.code.toByte().toInt()
    when (val xy = readVariableLengthLong()) {
      in 0L until 40L -> {
        result.writeDecimalLong(0)
        result.writeByte(dot)
        result.writeDecimalLong(xy)
      }
      in 40L until 80L -> {
        result.writeDecimalLong(1)
        result.writeByte(dot)
        result.writeDecimalLong(xy - 40L)
      }

1E65          ; valid                                  # 1.1  LATIN SMALL LETTER S WITH ACUTE AND DOT ABOVE
1E66          ; mapped                 ; 1E67          # 1.1  LATIN CAPITAL LETTER S WITH CARON AND DOT ABOVE
1E67          ; valid                                  # 1.1  LATIN SMALL LETTER S WITH CARON AND DOT ABOVE
1E68          ; mapped                 ; 1E69          # 1.1  LATIN CAPITAL LETTER S WITH DOT BELOW AND DOT ABOVE

  var labelStart = 0
  while (true) {
    val dot = indexOf('.', startIndex = labelStart)
    val labelLength =
      when (dot) {
        -1 -> length - labelStart
        else -> dot - labelStart
      }
    if (labelLength !in 1..63) return true
    if (dot == -1) break
    if (dot == length - 1) break // Trailing '.' is allowed.
    labelStart = dot + 1
  }

  return false
}

  private static final ImmutableSet<String> RS =
      ImmutableSet.of(
          // keep-sorted start
          "\u7f51\u7edc.Cn", // "网络.Cn"
          "co.uk",
          "co.uk.", // Trailing dot
          "co\uFF61uk", // Alternate dot character
          "com",
          "foo.bd",
          "org.mK",
          "us",
          "xxxxxx.bd",
          // keep-sorted end

      val vN = utf8.readDecimalLong()
      writeVariableLengthLong(vN)
    }
  }

  fun writeRelativeObjectIdentifier(s: String) {
    // Add a leading dot so each subidentifier has a dot prefix.
    val utf8 =
      Buffer()
        .writeByte('.'.code.toByte().toInt())
        .writeUtf8(s)

    while (!utf8.exhausted()) {
      require(utf8.readByte() == '.'.code.toByte())

  }

  private fun splitDomain(domain: String): List<String> {
    val domainLabels = domain.split('.')

    if (domainLabels.last() == "") {
      // allow for domain name trailing dot
      return domainLabels.dropLast(1)
    }

    return domainLabels
  }

  private fun findMatchingRule(domainLabels: List<String>): List<String> {
    publicSuffixList.ensureLoaded()

 * lookups.
 *
 * <p>During construction, names are normalized in two ways:
 *
 * <ol>
 *   <li>ASCII uppercase characters are converted to lowercase.
 *   <li>Unicode dot separators other than the ASCII period ({@code '.'}) are converted to the ASCII
 *       period.
 * </ol>
 *
 * <p>The normalized values will be returned from {@link #toString()} and {@link #parts()}, and will

      }
    }

    fun matchesHostname(hostname: String): Boolean =
      when {
        pattern.startsWith("**.") -> {
          // With ** empty prefixes match so exclude the dot from regionMatches().
          val suffixLength = pattern.length - 3
          val prefixLength = hostname.length - suffixLength
          hostname.regionMatches(hostname.length - suffixLength, pattern, 3, suffixLength) &&

# U+200B, U+2060, and U+FEFF, are ignored
http://GOO\u200b\u2060\ufeffgoo.com  s:http p:/ h:googoo.com

# Ideographic full stop (full-width period for Chinese, etc.) should be
# treated as a dot.
# U+3002 is mapped to U+002E (dot)
http://www.foo\u3002bar.com  s:http p:/ h:www.foo.bar.com

# Invalid unicode characters should fail...
# U+FDD0 is disallowed; %ef%b7%90 is U+FDD0
http://\ufdd0zyx.com