While converting larger trytes in IOTA, the conversion doesn't work reliably and produces different output than the conventional method.
const Trytes = require('trytes');
var RADIX = 3;
var RADIX_BYTES = 256;
var MAX_TRIT_VALUE = 1;
var MIN_TRIT_VALUE = -1;
var BYTE_HASH_LENGTH = 48;
// All possible tryte values
var trytesAlphabet = "9ABCDEFGHIJKLMNOPQRSTUVWXYZ"
// map of all trits representations
var trytesTrits = [
[ 0, 0, 0],
[ 1, 0, 0],
[-1, 1, 0],
[ 0, 1, 0],
[ 1, 1, 0],
[-1, -1, 1],
[ 0, -1, 1],
[ 1, -1, 1],
[-1, 0, 1],
[ 0, 0, 1],
[ 1, 0, 1],
[-1, 1, 1],
[ 0, 1, 1],
[ 1, 1, 1],
[-1, -1, -1],
[ 0, -1, -1],
[ 1, -1, -1],
[-1, 0, -1],
[ 0, 0, -1],
[ 1, 0, -1],
[-1, 1, -1],
[ 0, 1, -1],
[ 1, 1, -1],
[-1, -1, 0],
[ 0, -1, 0],
[ 1, -1, 0],
[-1, 0, 0]
];
function Trits( input, state ) {
var trits = state || [];
if (Number.isInteger(input)) {
var absoluteValue = input < 0 ? -input : input;
while (absoluteValue > 0) {
var remainder = absoluteValue % 3;
absoluteValue = Math.floor(absoluteValue / 3);
if (remainder > 1) {
remainder = -1;
absoluteValue++;
}
trits[trits.length] = remainder;
}
if (input < 0) {
for (var i = 0; i < trits.length; i++) {
trits[i] = -trits[i];
}
}
} else {
for (var i = 0; i < input.length; i++) {
var index = trytesAlphabet.indexOf(input.charAt(i));
trits[i * 3] = trytesTrits[index][0];
trits[i * 3 + 1] = trytesTrits[index][1];
trits[i * 3 + 2] = trytesTrits[index][2];
}
}
return trits;
}
const NUMBER_OF_TRITS_IN_A_BYTE = 5;
const NUMBER_OF_TRITS_IN_A_TRYTE = 3;
function Trits2Bytes(trits) {
var expectedLength = Math.floor((trits.length + NUMBER_OF_TRITS_IN_A_BYTE - 1) / NUMBER_OF_TRITS_IN_A_BYTE);
var output = new Uint8Array(expectedLength);
for (var i = 0; i < expectedLength; i++) {
var value = 0;
for (var j = (trits.length - i * NUMBER_OF_TRITS_IN_A_BYTE) < 5 ? (trits.length - i * NUMBER_OF_TRITS_IN_A_BYTE) : NUMBER_OF_TRITS_IN_A_BYTE; j-- > 0; ) {
value = value * 3 + trits[ i * NUMBER_OF_TRITS_IN_A_BYTE + j];
}
output[i] = value & 0xFF;
}
return output;
}
var raw = "999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999THIRRJFYZLEFMIWYVWLGUQST9A9A9CSJMD9M9MXQYYGKTEGJBYCVLPEJYNBARFUVZPTVFBOFWTVNPRTCX9SOVSA999999999999999999999999999999999999999999999999IBV9XZD99C99999999C99999999TRMRK9PYWHCSPCHLNAKHPEHI9BJUOILLILO9KCAHGNN9CUG9OXBQGRBMNDUTL9IQIAFYKWOWHKL9QIAOXZKGDXZNBSAKIZXSDUCHKVAATCSNV9RKOCE99IYHYSVVTECXFP9EQVZ9JFNZMSNOKCBVVEJQKXPOWYO999ZKGDXZNBSAKIZXSDUCHKVAATCSNV9RKOCE99IYHYSVVTECXFP9EQVZ9JNZMSNOKCBVVEJQKXPOWYO999999999999999999999999999999KMDGQWQLE999999999MMMMMMMMM9F9VUKQUCZWOOGZZSSYHQDCXNSK";
var trits = Trits(raw);
var bytes = Trits2Bytes(trits);
var bytes2 = Trytes.encodeTryteStringAsBytes(raw);
console.log("Length ", bytes.length, bytes2.length);
for ( var i = 0; i < bytes.length; i++){
if (bytes[i] !== bytes2[i]){
console.log("Index ", i, " unequal. ", bytes[i], bytes2[i]);
}
}
While converting larger trytes in IOTA, the conversion doesn't work reliably and produces different output than the conventional method.
Here is a program which demonstrates the problem