1
const textEncoder = new TextEncoder();
2
const textDecoder = new TextDecoder();
3
const base32Alphabet = "abcdefghijklmnopqrstuvwxyz234567";
4
 
5
export function utf8Bytes(value: string): Uint8Array {
6
  return textEncoder.encode(value);
7
}
8
 
9
export function utf8String(bytes: Uint8Array): string {
10
  return textDecoder.decode(bytes);
11
}
12
 
13
export function randomBytes(length: number): Uint8Array {
14
  const bytes = new Uint8Array(length);
15
  crypto.getRandomValues(bytes);
16
  return bytes;
17
}
18
 
19
export function hexFromBytes(bytes: Uint8Array): string {
20
  return [...bytes].map((byte) => byte.toString(16).padStart(2, "0")).join("");
21
}
22
 
23
export function randomHex(byteLength: number): string {
24
  return hexFromBytes(randomBytes(byteLength));
25
}
26
 
27
export function base32FromBytes(bytes: Uint8Array): string {
28
  let output = "";
29
  let buffer = 0;
30
  let bits = 0;
31
 
32
  for (const byte of bytes) {
33
    buffer = (buffer << 8) | byte;
34
    bits += 8;
35
 
36
    while (bits >= 5) {
37
      output += base32Alphabet[(buffer >>> (bits - 5)) & 31];
38
      bits -= 5;
39
    }
40
  }
41
 
42
  if (bits > 0) output += base32Alphabet[(buffer << (5 - bits)) & 31];
43
  return output;
44
}
45
 
46
export function base64UrlEncode(bytes: Uint8Array): string {
47
  let binary = "";
48
  for (const byte of bytes) binary += String.fromCharCode(byte);
49
  return btoa(binary).replace(/\+/g, "-").replace(/\//g, "_").replace(/=+$/g, "");
50
}
51
 
52
export function base64UrlDecode(value: string): Uint8Array {
53
  const normalized = value.replace(/-/g, "+").replace(/_/g, "/");
54
  const padded = normalized.padEnd(Math.ceil(normalized.length / 4) * 4, "=");
55
  const binary = atob(padded);
56
  const bytes = new Uint8Array(binary.length);
57
  for (let i = 0; i < binary.length; i += 1) bytes[i] = binary.charCodeAt(i);
58
  return bytes;
59
}
60
 
61
export function constantTimeEqual(a: string, b: string): boolean {
62
  const maxLength = Math.max(a.length, b.length);
63
  let diff = a.length ^ b.length;
64
 
65
  for (let i = 0; i < maxLength; i += 1) {
66
    diff |= (a.charCodeAt(i) || 0) ^ (b.charCodeAt(i) || 0);
67
  }
68
 
69
  return diff === 0;
70
}