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bech32.js (5161B)

---

 var ALPHABET = 'qpzry9x8gf2tvdw0s3jn54khce6mua7l';
 var ALPHABET_MAP = {};
 for (var z = 0; z < ALPHABET.length; z++) {
     var x = ALPHABET.charAt(z);
     ALPHABET_MAP[x] = z;
 }
 function polymodStep(pre) {
     var b = pre >> 25;
     return (((pre & 0x1ffffff) << 5) ^
         (-((b >> 0) & 1) & 0x3b6a57b2) ^
         (-((b >> 1) & 1) & 0x26508e6d) ^
         (-((b >> 2) & 1) & 0x1ea119fa) ^
         (-((b >> 3) & 1) & 0x3d4233dd) ^
         (-((b >> 4) & 1) & 0x2a1462b3));
 }
 function prefixChk(prefix) {
     var chk = 1;
     for (var i = 0; i < prefix.length; ++i) {
         var c = prefix.charCodeAt(i);
         if (c < 33 || c > 126)
             return 'Invalid prefix (' + prefix + ')';
         chk = polymodStep(chk) ^ (c >> 5);
     }
     chk = polymodStep(chk);
     for (var i = 0; i < prefix.length; ++i) {
         var v = prefix.charCodeAt(i);
         chk = polymodStep(chk) ^ (v & 0x1f);
     }
     return chk;
 }
 function convertbits(data, inBits, outBits, pad) {
     var value = 0;
     var bits = 0;
     var maxV = (1 << outBits) - 1;
     var result = [];
     for (var i = 0; i < data.length; ++i) {
         value = (value << inBits) | data[i];
         bits += inBits;
         while (bits >= outBits) {
             bits -= outBits;
             result.push((value >> bits) & maxV);
         }
     }
     if (pad) {
         if (bits > 0) {
             result.push((value << (outBits - bits)) & maxV);
         }
     }
     else {
         if (bits >= inBits)
             return 'Excess padding';
         if ((value << (outBits - bits)) & maxV)
             return 'Non-zero padding';
     }
     return result;
 }
 function toWords(bytes) {
     return convertbits(bytes, 8, 5, true);
 }
 function fromWordsUnsafe(words) {
     var res = convertbits(words, 5, 8, false);
     if (Array.isArray(res))
         return res;
 }
 function fromWords(words) {
     var res = convertbits(words, 5, 8, false);
     if (Array.isArray(res))
         return res;
     throw new Error(res);
 }
 function getLibraryFromEncoding(encoding) {
     var ENCODING_CONST;
     if (encoding === 'bech32') {
         ENCODING_CONST = 1;
     }
     else {
         ENCODING_CONST = 0x2bc830a3;
     }
     function encode(prefix, words, LIMIT) {
         LIMIT = LIMIT || 90;
         if (prefix.length + 7 + words.length > LIMIT)
             throw new TypeError('Exceeds length limit');
         prefix = prefix.toLowerCase();
         // determine chk mod
         var chk = prefixChk(prefix);
         if (typeof chk === 'string')
             throw new Error(chk);
         var result = prefix + '1';
         for (var i = 0; i < words.length; ++i) {
             var x = words[i];
             if (x >> 5 !== 0)
                 throw new Error('Non 5-bit word');
             chk = polymodStep(chk) ^ x;
             result += ALPHABET.charAt(x);
         }
         for (var i = 0; i < 6; ++i) {
             chk = polymodStep(chk);
         }
         chk ^= ENCODING_CONST;
         for (var i = 0; i < 6; ++i) {
             var v = (chk >> ((5 - i) * 5)) & 0x1f;
             result += ALPHABET.charAt(v);
         }
         return result;
     }
     function __decode(str, LIMIT) {
         LIMIT = LIMIT || 90;
         if (str.length < 8)
             return str + ' too short';
         if (str.length > LIMIT)
             return 'Exceeds length limit';
         // don't allow mixed case
         var lowered = str.toLowerCase();
         var uppered = str.toUpperCase();
         if (str !== lowered && str !== uppered)
             return 'Mixed-case string ' + str;
         str = lowered;
         var split = str.lastIndexOf('1');
         if (split === -1)
             return 'No separator character for ' + str;
         if (split === 0)
             return 'Missing prefix for ' + str;
         var prefix = str.slice(0, split);
         var wordChars = str.slice(split + 1);
         if (wordChars.length < 6)
             return 'Data too short';
         var chk = prefixChk(prefix);
         if (typeof chk === 'string')
             return chk;
         var words = [];
         for (var i = 0; i < wordChars.length; ++i) {
             var c = wordChars.charAt(i);
             var v = ALPHABET_MAP[c];
             if (v === undefined)
                 return 'Unknown character ' + c;
             chk = polymodStep(chk) ^ v;
             // not in the checksum?
             if (i + 6 >= wordChars.length)
                 continue;
             words.push(v);
         }
         if (chk !== ENCODING_CONST)
             return 'Invalid checksum for ' + str;
         return { prefix: prefix, words: words };
     }
     function decodeUnsafe(str, LIMIT) {
         var res = __decode(str, LIMIT);
         if (typeof res === 'object')
             return res;
     }
     function decode(str, LIMIT) {
         var res = __decode(str, LIMIT);
         if (typeof res === 'object')
             return res;
         throw new Error(res);
     }
     return {
         decodeUnsafe: decodeUnsafe,
         decode: decode,
         encode: encode,
         toWords: toWords,
         fromWordsUnsafe: fromWordsUnsafe,
         fromWords: fromWords
     };
 }
 
 const bech32 = getLibraryFromEncoding('bech32');
 const bech32m = getLibraryFromEncoding('bech32m');