(function () { 'use strict';

  // This is free and unencumbered software released into the public domain.
  // See LICENSE.md for more information.

  //
  // Utilities
  //

  /**
   * @param {number} a The number to test.
   * @param {number} min The minimum value in the range, inclusive.
   * @param {number} max The maximum value in the range, inclusive.
   * @return {boolean} True if a >= min and a <= max.
   */
  function inRange(a, min, max) {
    return min <= a && a <= max;
  }

  /**
   * @param {*} o
   * @return {Object}
   */
  function ToDictionary(o) {
    if (o === undefined) return {};
    if (o === Object(o)) return o;
    throw TypeError('Could not convert argument to dictionary');
  }

  /**
   * @param {string} string Input string of UTF-16 code units.
   * @return {!Array.<number>} Code points.
   */
  function stringToCodePoints(string) {
    // https://heycam.github.io/webidl/#dfn-obtain-unicode

    // 1. Let S be the DOMString value.
    var s = String(string);

    // 2. Let n be the length of S.
    var n = s.length;

    // 3. Initialize i to 0.
    var i = 0;

    // 4. Initialize U to be an empty sequence of Unicode characters.
    var u = [];

    // 5. While i < n:
    while (i < n) {

      // 1. Let c be the code unit in S at index i.
      var c = s.charCodeAt(i);

      // 2. Depending on the value of c:

      // c < 0xD800 or c > 0xDFFF
      if (c < 0xD800 || c > 0xDFFF) {
        // Append to U the Unicode character with code point c.
        u.push(c);
      }

      // 0xDC00 ≤ c ≤ 0xDFFF
      else if (0xDC00 <= c && c <= 0xDFFF) {
        // Append to U a U+FFFD REPLACEMENT CHARACTER.
        u.push(0xFFFD);
      }

      // 0xD800 ≤ c ≤ 0xDBFF
      else if (0xD800 <= c && c <= 0xDBFF) {
        // 1. If i = n−1, then append to U a U+FFFD REPLACEMENT
        // CHARACTER.
        if (i === n - 1) {
          u.push(0xFFFD);
        }
        // 2. Otherwise, i < n−1:
        else {
          // 1. Let d be the code unit in S at index i+1.
          var d = string.charCodeAt(i + 1);

          // 2. If 0xDC00 ≤ d ≤ 0xDFFF, then:
          if (0xDC00 <= d && d <= 0xDFFF) {
            // 1. Let a be c & 0x3FF.
            var a = c & 0x3FF;

            // 2. Let b be d & 0x3FF.
            var b = d & 0x3FF;

            // 3. Append to U the Unicode character with code point
            // 2^16+2^10*a+b.
            u.push(0x10000 + (a << 10) + b);

            // 4. Set i to i+1.
            i += 1;
          }

          // 3. Otherwise, d < 0xDC00 or d > 0xDFFF. Append to U a
          // U+FFFD REPLACEMENT CHARACTER.
          else  {
            u.push(0xFFFD);
          }
        }
      }

      // 3. Set i to i+1.
      i += 1;
    }

    // 6. Return U.
    return u;
  }

  /**
   * @param {!Array.<number>} code_points Array of code points.
   * @return {string} string String of UTF-16 code units.
   */
  function codePointsToString(code_points) {
    var s = '';
    for (var i = 0; i < code_points.length; ++i) {
      var cp = code_points[i];
      if (cp <= 0xFFFF) {
        s += String.fromCharCode(cp);
      } else {
        cp -= 0x10000;
        s += String.fromCharCode((cp >> 10) + 0xD800,
                                 (cp & 0x3FF) + 0xDC00);
      }
    }
    return s;
  }


  //
  // Implementation of Encoding specification
  // https://encoding.spec.whatwg.org/
  //

  //
  // 3. Terminology
  //

  /**
   * End-of-stream is a special token that signifies no more tokens
   * are in the stream.
   * @const
   */ var end_of_stream = -1;

  /**
   * A stream represents an ordered sequence of tokens.
   *
   * @constructor
   * @param {!(Array.<number>|Uint8Array)} tokens Array of tokens that provide the
   * stream.
   */
  function Stream(tokens) {
    /** @type {!Array.<number>} */
    this.tokens = [].slice.call(tokens);
  }

  Stream.prototype = {
    /**
     * @return {boolean} True if end-of-stream has been hit.
     */
    endOfStream: function() {
      return !this.tokens.length;
    },

    /**
     * When a token is read from a stream, the first token in the
     * stream must be returned and subsequently removed, and
     * end-of-stream must be returned otherwise.
     *
     * @return {number} Get the next token from the stream, or
     * end_of_stream.
     */
     read: function() {
      if (!this.tokens.length)
        return end_of_stream;
       return this.tokens.shift();
     },

    /**
     * When one or more tokens are prepended to a stream, those tokens
     * must be inserted, in given order, before the first token in the
     * stream.
     *
     * @param {(number|!Array.<number>)} token The token(s) to prepend to the stream.
     */
    prepend: function(token) {
      if (Array.isArray(token)) {
        var tokens = /**@type {!Array.<number>}*/(token);
        while (tokens.length)
          this.tokens.unshift(tokens.pop());
      } else {
        this.tokens.unshift(token);
      }
    },

    /**
     * When one or more tokens are pushed to a stream, those tokens
     * must be inserted, in given order, after the last token in the
     * stream.
     *
     * @param {(number|!Array.<number>)} token The tokens(s) to prepend to the stream.
     */
    push: function(token) {
      if (Array.isArray(token)) {
        var tokens = /**@type {!Array.<number>}*/(token);
        while (tokens.length)
          this.tokens.push(tokens.shift());
      } else {
        this.tokens.push(token);
      }
    }
  };

  //
  // 4. Encodings
  //

  // 4.1 Encoders and decoders

  /** @const */
  var finished = -1;

  /**
   * @param {boolean} fatal If true, decoding errors raise an exception.
   * @param {number=} opt_code_point Override the standard fallback code point.
   * @return {number} The code point to insert on a decoding error.
   */
  function decoderError(fatal, opt_code_point) {
    if (fatal)
      throw TypeError('Decoder error');
    return opt_code_point || 0xFFFD;
  }

  //
  // 7. API
  //

  /** @const */ var DEFAULT_ENCODING = 'utf-8';

  // 7.1 Interface TextDecoder

  /**
   * @constructor
   * @param {string=} encoding The label of the encoding;
   *     defaults to 'utf-8'.
   * @param {Object=} options
   */
  function TextDecoder$1(encoding, options) {
    if (!(this instanceof TextDecoder$1)) {
      return new TextDecoder$1(encoding, options);
    }
    encoding = encoding !== undefined ? String(encoding).toLowerCase() : DEFAULT_ENCODING;
    if (encoding !== DEFAULT_ENCODING) {
      throw new Error('Encoding not supported. Only utf-8 is supported');
    }
    options = ToDictionary(options);

    /** @private @type {boolean} */
    this._streaming = false;
    /** @private @type {boolean} */
    this._BOMseen = false;
    /** @private @type {?Decoder} */
    this._decoder = null;
    /** @private @type {boolean} */
    this._fatal = Boolean(options['fatal']);
    /** @private @type {boolean} */
    this._ignoreBOM = Boolean(options['ignoreBOM']);

    Object.defineProperty(this, 'encoding', {value: 'utf-8'});
    Object.defineProperty(this, 'fatal', {value: this._fatal});
    Object.defineProperty(this, 'ignoreBOM', {value: this._ignoreBOM});
  }

  TextDecoder$1.prototype = {
    /**
     * @param {ArrayBufferView=} input The buffer of bytes to decode.
     * @param {Object=} options
     * @return {string} The decoded string.
     */
    decode: function decode(input, options) {
      var bytes;
      if (typeof input === 'object' && input instanceof ArrayBuffer) {
        bytes = new Uint8Array(input);
      } else if (typeof input === 'object' && 'buffer' in input &&
                 input.buffer instanceof ArrayBuffer) {
        bytes = new Uint8Array(input.buffer,
                               input.byteOffset,
                               input.byteLength);
      } else {
        bytes = new Uint8Array(0);
      }

      options = ToDictionary(options);

      if (!this._streaming) {
        this._decoder = new UTF8Decoder({fatal: this._fatal});
        this._BOMseen = false;
      }
      this._streaming = Boolean(options['stream']);

      var input_stream = new Stream(bytes);

      var code_points = [];

      /** @type {?(number|!Array.<number>)} */
      var result;

      while (!input_stream.endOfStream()) {
        result = this._decoder.handler(input_stream, input_stream.read());
        if (result === finished)
          break;
        if (result === null)
          continue;
        if (Array.isArray(result))
          code_points.push.apply(code_points, /**@type {!Array.<number>}*/(result));
        else
          code_points.push(result);
      }
      if (!this._streaming) {
        do {
          result = this._decoder.handler(input_stream, input_stream.read());
          if (result === finished)
            break;
          if (result === null)
            continue;
          if (Array.isArray(result))
            code_points.push.apply(code_points, /**@type {!Array.<number>}*/(result));
          else
            code_points.push(result);
        } while (!input_stream.endOfStream());
        this._decoder = null;
      }

      if (code_points.length) {
        // If encoding is one of utf-8, utf-16be, and utf-16le, and
        // ignore BOM flag and BOM seen flag are unset, run these
        // subsubsteps:
        if (['utf-8'].indexOf(this.encoding) !== -1 &&
            !this._ignoreBOM && !this._BOMseen) {
          // If token is U+FEFF, set BOM seen flag.
          if (code_points[0] === 0xFEFF) {
            this._BOMseen = true;
            code_points.shift();
          } else {
            // Otherwise, if token is not end-of-stream, set BOM seen
            // flag and append token to output.
            this._BOMseen = true;
          }
        }
      }

      return codePointsToString(code_points);
    }
  };

  // 7.2 Interface TextEncoder

  /**
   * @constructor
   * @param {string=} encoding The label of the encoding;
   *     defaults to 'utf-8'.
   * @param {Object=} options
   */
  function TextEncoder$1(encoding, options) {
    if (!(this instanceof TextEncoder$1))
      return new TextEncoder$1(encoding, options);
    encoding = encoding !== undefined ? String(encoding).toLowerCase() : DEFAULT_ENCODING;
    if (encoding !== DEFAULT_ENCODING) {
      throw new Error('Encoding not supported. Only utf-8 is supported');
    }
    options = ToDictionary(options);

    /** @private @type {boolean} */
    this._streaming = false;
    /** @private @type {?Encoder} */
    this._encoder = null;
    /** @private @type {{fatal: boolean}} */
    this._options = {fatal: Boolean(options['fatal'])};

    Object.defineProperty(this, 'encoding', {value: 'utf-8'});
  }

  TextEncoder$1.prototype = {
    /**
     * @param {string=} opt_string The string to encode.
     * @param {Object=} options
     * @return {Uint8Array} Encoded bytes, as a Uint8Array.
     */
    encode: function encode(opt_string, options) {
      opt_string = opt_string ? String(opt_string) : '';
      options = ToDictionary(options);

      // NOTE: This option is nonstandard. None of the encodings
      // permitted for encoding (i.e. UTF-8, UTF-16) are stateful,
      // so streaming is not necessary.
      if (!this._streaming)
        this._encoder = new UTF8Encoder(this._options);
      this._streaming = Boolean(options['stream']);

      var bytes = [];
      var input_stream = new Stream(stringToCodePoints(opt_string));
      /** @type {?(number|!Array.<number>)} */
      var result;
      while (!input_stream.endOfStream()) {
        result = this._encoder.handler(input_stream, input_stream.read());
        if (result === finished)
          break;
        if (Array.isArray(result))
          bytes.push.apply(bytes, /**@type {!Array.<number>}*/(result));
        else
          bytes.push(result);
      }
      if (!this._streaming) {
        while (true) {
          result = this._encoder.handler(input_stream, input_stream.read());
          if (result === finished)
            break;
          if (Array.isArray(result))
            bytes.push.apply(bytes, /**@type {!Array.<number>}*/(result));
          else
            bytes.push(result);
        }
        this._encoder = null;
      }
      return new Uint8Array(bytes);
    }
  };

  //
  // 8. The encoding
  //

  // 8.1 utf-8

  /**
   * @constructor
   * @implements {Decoder}
   * @param {{fatal: boolean}} options
   */
  function UTF8Decoder(options) {
    var fatal = options.fatal;

    // utf-8's decoder's has an associated utf-8 code point, utf-8
    // bytes seen, and utf-8 bytes needed (all initially 0), a utf-8
    // lower boundary (initially 0x80), and a utf-8 upper boundary
    // (initially 0xBF).
    var /** @type {number} */ utf8_code_point = 0,
        /** @type {number} */ utf8_bytes_seen = 0,
        /** @type {number} */ utf8_bytes_needed = 0,
        /** @type {number} */ utf8_lower_boundary = 0x80,
        /** @type {number} */ utf8_upper_boundary = 0xBF;

    /**
     * @param {Stream} stream The stream of bytes being decoded.
     * @param {number} bite The next byte read from the stream.
     * @return {?(number|!Array.<number>)} The next code point(s)
     *     decoded, or null if not enough data exists in the input
     *     stream to decode a complete code point.
     */
    this.handler = function(stream, bite) {
      // 1. If byte is end-of-stream and utf-8 bytes needed is not 0,
      // set utf-8 bytes needed to 0 and return error.
      if (bite === end_of_stream && utf8_bytes_needed !== 0) {
        utf8_bytes_needed = 0;
        return decoderError(fatal);
      }

      // 2. If byte is end-of-stream, return finished.
      if (bite === end_of_stream)
        return finished;

      // 3. If utf-8 bytes needed is 0, based on byte:
      if (utf8_bytes_needed === 0) {

        // 0x00 to 0x7F
        if (inRange(bite, 0x00, 0x7F)) {
          // Return a code point whose value is byte.
          return bite;
        }

        // 0xC2 to 0xDF
        if (inRange(bite, 0xC2, 0xDF)) {
          // Set utf-8 bytes needed to 1 and utf-8 code point to byte
          // − 0xC0.
          utf8_bytes_needed = 1;
          utf8_code_point = bite - 0xC0;
        }

        // 0xE0 to 0xEF
        else if (inRange(bite, 0xE0, 0xEF)) {
          // 1. If byte is 0xE0, set utf-8 lower boundary to 0xA0.
          if (bite === 0xE0)
            utf8_lower_boundary = 0xA0;
          // 2. If byte is 0xED, set utf-8 upper boundary to 0x9F.
          if (bite === 0xED)
            utf8_upper_boundary = 0x9F;
          // 3. Set utf-8 bytes needed to 2 and utf-8 code point to
          // byte − 0xE0.
          utf8_bytes_needed = 2;
          utf8_code_point = bite - 0xE0;
        }

        // 0xF0 to 0xF4
        else if (inRange(bite, 0xF0, 0xF4)) {
          // 1. If byte is 0xF0, set utf-8 lower boundary to 0x90.
          if (bite === 0xF0)
            utf8_lower_boundary = 0x90;
          // 2. If byte is 0xF4, set utf-8 upper boundary to 0x8F.
          if (bite === 0xF4)
            utf8_upper_boundary = 0x8F;
          // 3. Set utf-8 bytes needed to 3 and utf-8 code point to
          // byte − 0xF0.
          utf8_bytes_needed = 3;
          utf8_code_point = bite - 0xF0;
        }

        // Otherwise
        else {
          // Return error.
          return decoderError(fatal);
        }

        // Then (byte is in the range 0xC2 to 0xF4) set utf-8 code
        // point to utf-8 code point << (6 × utf-8 bytes needed) and
        // return continue.
        utf8_code_point = utf8_code_point << (6 * utf8_bytes_needed);
        return null;
      }

      // 4. If byte is not in the range utf-8 lower boundary to utf-8
      // upper boundary, run these substeps:
      if (!inRange(bite, utf8_lower_boundary, utf8_upper_boundary)) {

        // 1. Set utf-8 code point, utf-8 bytes needed, and utf-8
        // bytes seen to 0, set utf-8 lower boundary to 0x80, and set
        // utf-8 upper boundary to 0xBF.
        utf8_code_point = utf8_bytes_needed = utf8_bytes_seen = 0;
        utf8_lower_boundary = 0x80;
        utf8_upper_boundary = 0xBF;

        // 2. Prepend byte to stream.
        stream.prepend(bite);

        // 3. Return error.
        return decoderError(fatal);
      }

      // 5. Set utf-8 lower boundary to 0x80 and utf-8 upper boundary
      // to 0xBF.
      utf8_lower_boundary = 0x80;
      utf8_upper_boundary = 0xBF;

      // 6. Increase utf-8 bytes seen by one and set utf-8 code point
      // to utf-8 code point + (byte − 0x80) << (6 × (utf-8 bytes
      // needed − utf-8 bytes seen)).
      utf8_bytes_seen += 1;
      utf8_code_point += (bite - 0x80) << (6 * (utf8_bytes_needed - utf8_bytes_seen));

      // 7. If utf-8 bytes seen is not equal to utf-8 bytes needed,
      // continue.
      if (utf8_bytes_seen !== utf8_bytes_needed)
        return null;

      // 8. Let code point be utf-8 code point.
      var code_point = utf8_code_point;

      // 9. Set utf-8 code point, utf-8 bytes needed, and utf-8 bytes
      // seen to 0.
      utf8_code_point = utf8_bytes_needed = utf8_bytes_seen = 0;

      // 10. Return a code point whose value is code point.
      return code_point;
    };
  }

  /**
   * @constructor
   * @implements {Encoder}
   * @param {{fatal: boolean}} options
   */
  function UTF8Encoder(options) {
    var fatal = options.fatal;
    /**
     * @param {Stream} stream Input stream.
     * @param {number} code_point Next code point read from the stream.
     * @return {(number|!Array.<number>)} Byte(s) to emit.
     */
    this.handler = function(stream, code_point) {
      // 1. If code point is end-of-stream, return finished.
      if (code_point === end_of_stream)
        return finished;

      // 2. If code point is in the range U+0000 to U+007F, return a
      // byte whose value is code point.
      if (inRange(code_point, 0x0000, 0x007f))
        return code_point;

      // 3. Set count and offset based on the range code point is in:
      var count, offset;
      // U+0080 to U+07FF:    1 and 0xC0
      if (inRange(code_point, 0x0080, 0x07FF)) {
        count = 1;
        offset = 0xC0;
      }
      // U+0800 to U+FFFF:    2 and 0xE0
      else if (inRange(code_point, 0x0800, 0xFFFF)) {
        count = 2;
        offset = 0xE0;
      }
      // U+10000 to U+10FFFF: 3 and 0xF0
      else if (inRange(code_point, 0x10000, 0x10FFFF)) {
        count = 3;
        offset = 0xF0;
      }

      // 4.Let bytes be a byte sequence whose first byte is (code
      // point >> (6 × count)) + offset.
      var bytes = [(code_point >> (6 * count)) + offset];

      // 5. Run these substeps while count is greater than 0:
      while (count > 0) {

        // 1. Set temp to code point >> (6 × (count − 1)).
        var temp = code_point >> (6 * (count - 1));

        // 2. Append to bytes 0x80 | (temp & 0x3F).
        bytes.push(0x80 | (temp & 0x3F));

        // 3. Decrease count by one.
        count -= 1;
      }

      // 6. Return bytes bytes, in order.
      return bytes;
    };
  }

  function getGlobal() {
    if (typeof self !== 'undefined') return self;
    if (typeof global !== 'undefined') return global;
    throw new Error('No global found');
  }

  if (typeof TextDecoder !== 'function') {
    getGlobal().TextDecoder = TextDecoder$1;
  }

  if (typeof TextEncoder !== 'function') {
    getGlobal().TextEncoder = TextEncoder$1;
  }

})();