@stellot/crypto/lib/esm/secretBox/secretMemo.js

Crypto libraries for front and backend

import { encrypt, decrypt } from './stellarBox';
import Long from 'long';
import { Memo, MemoID, MemoHash, MemoReturn, MemoText, } from 'stellar-sdk';
const padding = Buffer.alloc(8);
async function work(fn, sequenceNumber, keys, to, memo) {
    if (!memo.value) {
        throw new Error('Invalid memo value');
    }
    const seqNum = Long.fromString(sequenceNumber);
    const nonce = Buffer.concat([
        padding,
        Buffer.from(seqNum.mul(2).toBytesBE())
    ]);
    if (memo.type === MemoText) {
        const data = Buffer.from(memo.value);
        const res = await fn(keys, to, data, nonce, false);
        const value = Buffer.from(res);
        return new Memo(memo.type, value);
    }
    else if (memo.type === MemoID) {
        const data = Buffer.from(Long.fromString(memo.value, true).toBytesBE());
        const res = await fn(keys, to, data, nonce, false);
        const value = Long.fromBytesBE(res, true).toString();
        return new Memo(memo.type, value);
    }
    else if ((memo.type === MemoHash) || (memo.type === MemoReturn)) {
        const data = memo.value;
        const res = await fn(keys, to, data, nonce, false);
        const value = Buffer.from(res);
        return new Memo(memo.type, value);
    }
    else {
        throw new Error('Invalid memo type');
    }
}
export function encodeMemo(sequenceNumber, keys, to, memo) {
    const sequence = Long.fromString(sequenceNumber).add(1).toString();
    return work(encrypt, sequence, keys, to, memo);
}
export function decodeMemo(sequenceNumber, keys, from, memo) {
    return work(decrypt, sequenceNumber, keys, from, memo);
}
export function decodeTransactionMemo(tx, keys) {
    return work(decrypt, tx.sequence, keys, tx.source, tx.memo);
}