Files
common/packages/util-crypto/src/base32/encode.ts
T
2021-01-03 11:20:22 +01:00

42 lines
1.1 KiB
TypeScript

// Copyright 2017-2021 @polkadot/util-crypto authors & contributors
// SPDX-License-Identifier: Apache-2.0
// adapted from https://github.com/multiformats/js-multibase/blob/424709195b46ffb1d6f2f69a7707598ebe751e5e/src/rfc4648.js
import { u8aToU8a } from '@polkadot/util';
import { BASE32_ALPHABET, BITS_PER_CHAR } from './bs32';
const MASK = (1 << BITS_PER_CHAR) - 1;
/**
* @name base32Encode
* @summary Creates a base32 value.
* @description
* From the provided input, create the base32 and return the result as a string.
*/
export function base32Encode (value: Uint8Array | string | Buffer | number[], ipfsCompat = false): string {
const u8a = u8aToU8a(value);
let out = '';
let bits = 0;
let buffer = 0;
for (let i = 0; i < u8a.length; ++i) {
buffer = (buffer << 8) | u8a[i];
bits += 8;
while (bits > BITS_PER_CHAR) {
bits -= BITS_PER_CHAR;
out += BASE32_ALPHABET[MASK & (buffer >> bits)];
}
}
if (bits) {
out += BASE32_ALPHABET[MASK & (buffer << (BITS_PER_CHAR - bits))];
}
return ipfsCompat
? `b${out}`
: out;
}