* limitations under the License.
 */
package okhttp3.internal.idn

import okio.Buffer
import okio.ByteString.Companion.encodeUtf8

/**
 * An [RFC 3492] punycode decoder for converting ASCII to Unicode domain name labels. This is
 * intended for use in Internationalized Domain Names (IDNs).
 *
 * This class contains a Kotlin implementation of the pseudocode specified by RFC 3492. It includes

    )
    assertNull(
      Punycode.encode(a1000MaxCodePoint.repeat(2)),
    )
  }

  @Test fun invalidPunycode() {
    assertNull(Punycode.decode("xn--ls8h="))
  }

  private fun testEncodeDecode(
    unicode: String,
    punycode: String,
  ) {
    assertEquals(unicode, Punycode.decode(punycode))
    assertEquals(punycode, Punycode.encode(unicode))
  }

  private fun testDecodeOnly(

    "output": "x..xn--zca"
  },
  {
    "comment": "Invalid Punycode",
    "input": "xn--a",
    "output": null
  },
  {
    "input": "xn--a.xn--zca",
    "output": null
  },
  {
    "input": "xn--a.ß",
    "output": null
  },
  {
    "input": "xn--ls8h=",
    "output": null
  },
  {
    "comment": "Invalid Punycode (contains non-ASCII character)",
    "input": "xn--tešla",
    "output": null

      }
    },

    /** URLs that contain this character in this component are invalid.  */
    FORBIDDEN,

    /** Hostnames that contain this character are encoded with punycode.  */
    PUNYCODE,

    /** This code point is special and should not be tested.  */
    SKIP,

    ;

    open fun encode(codePoint: Int): String {
      throw UnsupportedOperationException()
    }

      // OkHttp does not reject invalid Punycode.
      "xn--a",
      "xn--a.ß",
      "xn--a.xn--zca",
      "xn--a-yoc",
      // OkHttp doesn't reject U+FFFD encoded in Punycode.
      "xn--zn7c.com",
      // OkHttp doesn't reject a U+200D. https://www.rfc-editor.org/rfc/rfc5892.html#appendix-A.2
      "xn--1ug.example",

  }

  // 2. Normalize, from bufferB to bufferA.
  val normalized = normalizeNfc(bufferB.readUtf8())
  bufferA.writeUtf8(normalized)

  // 3. For each label, convert/validate Punycode.
  val decoded = Punycode.decode(bufferA.readUtf8()) ?: return null

  // 4.1 Validate.

  // Must be NFC.
  if (decoded != normalizeNfc(decoded)) return null

  // TODO: Must not begin with a combining mark.

    val unicode = "https://長.長.長崎.jp".toHttpUrl()
    assertThat(parse(unicode, "a=b; domain=長.長崎.jp")).isNotNull()
    assertThat(parse(unicode, "a=b; domain=長崎.jp")).isNull()
    val punycode = "https://xn--ue5a.xn--ue5a.xn--8ltr62k.jp".toHttpUrl()
    assertThat(parse(punycode, "a=b; domain=xn--ue5a.xn--8ltr62k.jp")).isNotNull()
    assertThat(parse(punycode, "a=b; domain=xn--8ltr62k.jp")).isNull()
  }

    return name;
  }

  /**
   * Equality testing is based on the text supplied by the caller, after normalization as described
   * in the class documentation. For example, a non-ASCII Unicode domain name and the Punycode
   * version of the same domain name would not be considered equal.
   */
  @Override
  public boolean equals(@CheckForNull Object object) {
    if (object == this) {
      return true;
    }

   * ```
   *
   * @param domain A canonicalized domain. An International Domain Name (IDN) should be punycode
   *     encoded.
   */
  fun getEffectiveTldPlusOne(domain: String): String? {
    // We use UTF-8 in the list so we need to convert to Unicode.
    val unicodeDomain = IDN.toUnicode(domain)
    val domainLabels = splitDomain(unicodeDomain)

    val rule = findMatchingRule(domainLabels)

      .isEqualTo("http://a$dotA126/")
    assertInvalid("http://aa$dotA126/", "Invalid URL host: \"aa$dotA126\"")
  }

  /**
   * UTS 46 Validity Criteria: Decoded punycode must be NFC.
   *
   * https://www.unicode.org/reports/tr46/#Validity_Criteria
   */
  @Test
  fun hostnameInPunycodeNfcAndNfd() {
    // café can be NFC (é is one code point) or NFD (e plus ´ as two code points).