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+/*
+Copyright Mathias Bynens <https://mathiasbynens.be/>
+Copyright (c) 2022 Taler Systems S.A.
+
+Permission is hereby granted, free of charge, to any person obtaining
+a copy of this software and associated documentation files (the
+"Software"), to deal in the Software without restriction, including
+without limitation the rights to use, copy, modify, merge, publish,
+distribute, sublicense, and/or sell copies of the Software, and to
+permit persons to whom the Software is furnished to do so, subject to
+the following conditions:
+
+The above copyright notice and this permission notice shall be
+included in all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+*/
+
+/** Highest positive signed 32-bit float value */
+const maxInt = 2147483647; // aka. 0x7FFFFFFF or 2^31-1
+
+/** Bootstring parameters */
+const base = 36;
+const tMin = 1;
+const tMax = 26;
+const skew = 38;
+const damp = 700;
+const initialBias = 72;
+const initialN = 128; // 0x80
+const delimiter = "-"; // '\x2D'
+
+/** Regular expressions */
+const regexPunycode = /^xn--/;
+const regexNonASCII = /[^\0-\x7E]/; // non-ASCII chars
+const regexSeparators = /[\x2E\u3002\uFF0E\uFF61]/g; // RFC 3490 separators
+
+/** Error messages */
+const errors = {
+  overflow: "Overflow: input needs wider integers to process",
+  "not-basic": "Illegal input >= 0x80 (not a basic code point)",
+  "invalid-input": "Invalid input",
+} as { [x: string]: string };
+
+/** Convenience shortcuts */
+const baseMinusTMin = base - tMin;
+const floor = Math.floor;
+const stringFromCharCode = String.fromCharCode;
+
+/*--------------------------------------------------------------------------*/
+
+/**
+ * A generic error utility function.
+ * @private
+ * @param {String} type The error type.
+ * @returns {Error} Throws a `RangeError` with the applicable error message.
+ */
+function error(type: string) {
+  throw new RangeError(errors[type]);
+}
+
+/**
+ * A generic `Array#map` utility function.
+ * @private
+ * @param {Array} array The array to iterate over.
+ * @param {Function} callback The function that gets called for every array
+ * item.
+ * @returns {Array} A new array of values returned by the callback function.
+ */
+function map(array: any[], fn: (arg0: any) => any) {
+  const result = [];
+  let length = array.length;
+  while (length--) {
+    result[length] = fn(array[length]);
+  }
+  return result;
+}
+
+/**
+ * A simple `Array#map`-like wrapper to work with domain name strings or email
+ * addresses.
+ * @private
+ * @param {String} domain The domain name or email address.
+ * @param {Function} callback The function that gets called for every
+ * character.
+ * @returns {Array} A new string of characters returned by the callback
+ * function.
+ */
+function mapDomain(
+  string: string,
+  fn: { (string: any): any; (string: any): any; (arg0: any): any },
+) {
+  const parts = string.split("@");
+  let result = "";
+  if (parts.length > 1) {
+    // In email addresses, only the domain name should be punycoded. Leave
+    // the local part (i.e. everything up to `@`) intact.
+    result = parts[0] + "@";
+    string = parts[1];
+  }
+  // Avoid `split(regex)` for IE8 compatibility. See #17.
+  string = string.replace(regexSeparators, "\x2E");
+  const labels = string.split(".");
+  const encoded = map(labels, fn).join(".");
+  return result + encoded;
+}
+
+/**
+ * Creates an array containing the numeric code points of each Unicode
+ * character in the string. While JavaScript uses UCS-2 internally,
+ * this function will convert a pair of surrogate halves (each of which
+ * UCS-2 exposes as separate characters) into a single code point,
+ * matching UTF-16.
+ * @see `punycode.ucs2.encode`
+ * @see <https://mathiasbynens.be/notes/javascript-encoding>
+ * @memberOf punycode.ucs2
+ * @name decode
+ * @param {String} string The Unicode input string (UCS-2).
+ * @returns {Array} The new array of code points.
+ */
+function ucs2decode(string: string) {
+  const output = [];
+  let counter = 0;
+  const length = string.length;
+  while (counter < length) {
+    const value = string.charCodeAt(counter++);
+    if (value >= 0xd800 && value <= 0xdbff && counter < length) {
+      // It's a high surrogate, and there is a next character.
+      const extra = string.charCodeAt(counter++);
+      if ((extra & 0xfc00) == 0xdc00) {
+        // Low surrogate.
+        output.push(((value & 0x3ff) << 10) + (extra & 0x3ff) + 0x10000);
+      } else {
+        // It's an unmatched surrogate; only append this code unit, in case the
+        // next code unit is the high surrogate of a surrogate pair.
+        output.push(value);
+        counter--;
+      }
+    } else {
+      output.push(value);
+    }
+  }
+  return output;
+}
+
+/**
+ * Creates a string based on an array of numeric code points.
+ * @see `punycode.ucs2.decode`
+ * @memberOf punycode.ucs2
+ * @name encode
+ * @param {Array} codePoints The array of numeric code points.
+ * @returns {String} The new Unicode string (UCS-2).
+ */
+const ucs2encode = (array: any): string => String.fromCodePoint(...array);
+
+/**
+ * Converts a basic code point into a digit/integer.
+ * @see `digitToBasic()`
+ * @private
+ * @param {Number} codePoint The basic numeric code point value.
+ * @returns {Number} The numeric value of a basic code point (for use in
+ * representing integers) in the range `0` to `base - 1`, or `base` if
+ * the code point does not represent a value.
+ */
+const basicToDigit = function (codePoint: number) {
+  if (codePoint - 0x30 < 0x0a) {
+    return codePoint - 0x16;
+  }
+  if (codePoint - 0x41 < 0x1a) {
+    return codePoint - 0x41;
+  }
+  if (codePoint - 0x61 < 0x1a) {
+    return codePoint - 0x61;
+  }
+  return base;
+};
+
+/**
+ * Converts a digit/integer into a basic code point.
+ * @see `basicToDigit()`
+ * @private
+ * @param {Number} digit The numeric value of a basic code point.
+ * @returns {Number} The basic code point whose value (when used for
+ * representing integers) is `digit`, which needs to be in the range
+ * `0` to `base - 1`. If `flag` is non-zero, the uppercase form is
+ * used; else, the lowercase form is used. The behavior is undefined
+ * if `flag` is non-zero and `digit` has no uppercase form.
+ */
+const digitToBasic = function (digit: number, flag: number) {
+  //  0..25 map to ASCII a..z or A..Z
+  // 26..35 map to ASCII 0..9
+  return digit + 22 + 75 * Number(digit < 26) - (Number(flag != 0) << 5);
+};
+
+/**
+ * Bias adaptation function as per section 3.4 of RFC 3492.
+ * https://tools.ietf.org/html/rfc3492#section-3.4
+ * @private
+ */
+const adapt = function (delta: number, numPoints: number, firstTime: boolean) {
+  let k = 0;
+  delta = firstTime ? floor(delta / damp) : delta >> 1;
+  delta += floor(delta / numPoints);
+  for (
+    ;
+    /* no initialization */ delta > (baseMinusTMin * tMax) >> 1;
+    k += base
+  ) {
+    delta = floor(delta / baseMinusTMin);
+  }
+  return floor(k + ((baseMinusTMin + 1) * delta) / (delta + skew));
+};
+
+/**
+ * Converts a Punycode string of ASCII-only symbols to a string of Unicode
+ * symbols.
+ * @memberOf punycode
+ * @param {String} input The Punycode string of ASCII-only symbols.
+ * @returns {String} The resulting string of Unicode symbols.
+ */
+const decode = function (input: string) {
+  // Don't use UCS-2.
+  const output = [];
+  const inputLength = input.length;
+  let i = 0;
+  let n = initialN;
+  let bias = initialBias;
+
+  // Handle the basic code points: let `basic` be the number of input code
+  // points before the last delimiter, or `0` if there is none, then copy
+  // the first basic code points to the output.
+
+  let basic = input.lastIndexOf(delimiter);
+  if (basic < 0) {
+    basic = 0;
+  }
+
+  for (let j = 0; j < basic; ++j) {
+    // if it's not a basic code point
+    if (input.charCodeAt(j) >= 0x80) {
+      error("not-basic");
+    }
+    output.push(input.charCodeAt(j));
+  }
+
+  // Main decoding loop: start just after the last delimiter if any basic code
+  // points were copied; start at the beginning otherwise.
+
+  for (
+    let index = basic > 0 ? basic + 1 : 0;
+    index < inputLength /* no final expression */;
+
+  ) {
+    // `index` is the index of the next character to be consumed.
+    // Decode a generalized variable-length integer into `delta`,
+    // which gets added to `i`. The overflow checking is easier
+    // if we increase `i` as we go, then subtract off its starting
+    // value at the end to obtain `delta`.
+    let oldi = i;
+    for (let w = 1, k = base /* no condition */; ; k += base) {
+      if (index >= inputLength) {
+        error("invalid-input");
+      }
+
+      const digit = basicToDigit(input.charCodeAt(index++));
+
+      if (digit >= base || digit > floor((maxInt - i) / w)) {
+        error("overflow");
+      }
+
+      i += digit * w;
+      const t = k <= bias ? tMin : k >= bias + tMax ? tMax : k - bias;
+
+      if (digit < t) {
+        break;
+      }
+
+      const baseMinusT = base - t;
+      if (w > floor(maxInt / baseMinusT)) {
+        error("overflow");
+      }
+
+      w *= baseMinusT;
+    }
+
+    const out = output.length + 1;
+    bias = adapt(i - oldi, out, oldi == 0);
+
+    // `i` was supposed to wrap around from `out` to `0`,
+    // incrementing `n` each time, so we'll fix that now:
+    if (floor(i / out) > maxInt - n) {
+      error("overflow");
+    }
+
+    n += floor(i / out);
+    i %= out;
+
+    // Insert `n` at position `i` of the output.
+    output.splice(i++, 0, n);
+  }
+
+  return String.fromCodePoint(...output);
+};
+
+/**
+ * Converts a string of Unicode symbols (e.g. a domain name label) to a
+ * Punycode string of ASCII-only symbols.
+ * @memberOf punycode
+ * @param {String} input The string of Unicode symbols.
+ * @returns {String} The resulting Punycode string of ASCII-only symbols.
+ */
+const encode = function (inputArg: string) {
+  const output = [];
+
+  // Convert the input in UCS-2 to an array of Unicode code points.
+  let input = ucs2decode(inputArg);
+
+  // Cache the length.
+  let inputLength = input.length;
+
+  // Initialize the state.
+  let n = initialN;
+  let delta = 0;
+  let bias = initialBias;
+
+  // Handle the basic code points.
+  for (const currentValue of input) {
+    if (currentValue < 0x80) {
+      output.push(stringFromCharCode(currentValue));
+    }
+  }
+
+  let basicLength = output.length;
+  let handledCPCount = basicLength;
+
+  // `handledCPCount` is the number of code points that have been handled;
+  // `basicLength` is the number of basic code points.
+
+  // Finish the basic string with a delimiter unless it's empty.
+  if (basicLength) {
+    output.push(delimiter);
+  }
+
+  // Main encoding loop:
+  while (handledCPCount < inputLength) {
+    // All non-basic code points < n have been handled already. Find the next
+    // larger one:
+    let m = maxInt;
+    for (const currentValue of input) {
+      if (currentValue >= n && currentValue < m) {
+        m = currentValue;
+      }
+    }
+
+    // Increase `delta` enough to advance the decoder's <n,i> state to <m,0>,
+    // but guard against overflow.
+    const handledCPCountPlusOne = handledCPCount + 1;
+    if (m - n > floor((maxInt - delta) / handledCPCountPlusOne)) {
+      error("overflow");
+    }
+
+    delta += (m - n) * handledCPCountPlusOne;
+    n = m;
+
+    for (const currentValue of input) {
+      if (currentValue < n && ++delta > maxInt) {
+        error("overflow");
+      }
+      if (currentValue == n) {
+        // Represent delta as a generalized variable-length integer.
+        let q = delta;
+        for (let k = base /* no condition */; ; k += base) {
+          const t = k <= bias ? tMin : k >= bias + tMax ? tMax : k - bias;
+          if (q < t) {
+            break;
+          }
+          const qMinusT = q - t;
+          const baseMinusT = base - t;
+          output.push(
+            stringFromCharCode(digitToBasic(t + (qMinusT % baseMinusT), 0)),
+          );
+          q = floor(qMinusT / baseMinusT);
+        }
+
+        output.push(stringFromCharCode(digitToBasic(q, 0)));
+        bias = adapt(
+          delta,
+          handledCPCountPlusOne,
+          handledCPCount == basicLength,
+        );
+        delta = 0;
+        ++handledCPCount;
+      }
+    }
+
+    ++delta;
+    ++n;
+  }
+  return output.join("");
+};
+
+/**
+ * Converts a Punycode string representing a domain name or an email address
+ * to Unicode. Only the Punycoded parts of the input will be converted, i.e.
+ * it doesn't matter if you call it on a string that has already been
+ * converted to Unicode.
+ * @memberOf punycode
+ * @param {String} input The Punycoded domain name or email address to
+ * convert to Unicode.
+ * @returns {String} The Unicode representation of the given Punycode
+ * string.
+ */
+const toUnicode = function (input: string) {
+  return mapDomain(input, function (string) {
+    return regexPunycode.test(string)
+      ? decode(string.slice(4).toLowerCase())
+      : string;
+  });
+};
+
+/**
+ * Converts a Unicode string representing a domain name or an email address to
+ * Punycode. Only the non-ASCII parts of the domain name will be converted,
+ * i.e. it doesn't matter if you call it with a domain that's already in
+ * ASCII.
+ * @memberOf punycode
+ * @param {String} input The domain name or email address to convert, as a
+ * Unicode string.
+ * @returns {String} The Punycode representation of the given domain name or
+ * email address.
+ */
+const toASCII = function (input: string) {
+  return mapDomain(input, function (string) {
+    return regexNonASCII.test(string) ? "xn--" + encode(string) : string;
+  });
+};
+
+/*--------------------------------------------------------------------------*/
+
+/** Define the public API */
+export const punycode = {
+  /**
+   * A string representing the current Punycode.js version number.
+   * @memberOf punycode
+   * @type String
+   */
+  version: "2.1.0",
+  /**
+   * An object of methods to convert from JavaScript's internal character
+   * representation (UCS-2) to Unicode code points, and back.
+   * @see <https://mathiasbynens.be/notes/javascript-encoding>
+   * @memberOf punycode
+   * @type Object
+   */
+  ucs2: {
+    decode: ucs2decode,
+    encode: ucs2encode,
+  },
+  decode: decode,
+  encode: encode,
+  toASCII: toASCII,
+  toUnicode: toUnicode,
+};