1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
|
// CLINK offer codes (`noffer1…`) — a static, nostr-native payment code.
// Bech32 over TLV: 0 = service pubkey (32B), 1 = relay url, 2 = offer id,
// 3 = pricing type (2 = payer chooses the amount). A payer decodes this,
// sends a NIP-44-encrypted kind-21001 request to the pubkey via the relay,
// and gets an invoice back — no web server involved.
import { bech32 } from '@scure/base';
import { hex } from '@scure/base';
const te = new TextEncoder();
const td = new TextDecoder();
function tlv(items) {
const parts = [];
for (const [type, value] of items) {
if (value.length > 255) throw new Error('tlv value too long');
parts.push(new Uint8Array([type, value.length]), value);
}
const total = parts.reduce((n, p) => n + p.length, 0);
const out = new Uint8Array(total);
let off = 0;
for (const p of parts) { out.set(p, off); off += p.length; }
return out;
}
export function encodeNoffer({ pubkey, relay, offerId, priceType = 2 }) {
const data = tlv([
[0, hex.decode(pubkey)],
[1, te.encode(relay)],
[2, te.encode(offerId)],
[3, new Uint8Array([priceType])],
]);
return bech32.encode('noffer', bech32.toWords(data), 2000);
}
export function decodeNoffer(str) {
const { prefix, words } = bech32.decode(String(str).trim(), 2000);
if (prefix !== 'noffer') throw new Error('not an offer code');
const data = bech32.fromWords(words);
const out = {};
let off = 0;
while (off + 2 <= data.length) {
const type = data[off], len = data[off + 1];
const value = data.slice(off + 2, off + 2 + len);
off += 2 + len;
if (type === 0) out.pubkey = hex.encode(value);
else if (type === 1) out.relay = td.decode(value);
else if (type === 2) out.offerId = td.decode(value);
else if (type === 3) out.priceType = value[0];
else if (type === 4) out.priceSats = [...value].reduce((n, b) => n * 256 + b, 0);
else if (type === 5) out.currency = td.decode(value);
}
if (!out.pubkey) throw new Error('offer code has no pubkey');
return out;
}
|
