add nip59 (#438)

* feat(nip59) add nip59 based on https://nips.nostr.com/59

* fix(nip59) export the code as nip59

* Update nip59.ts

Co-authored-by: Asai Toshiya <to.asai.60@gmail.com>

* fix(nip59) change GiftWrap kind and using kinds from kinds.ts

---------

Co-authored-by: Asai Toshiya <to.asai.60@gmail.com>

index.ts

@@ -21,6 +21,7 @@ export * as nip42 from './nip42.ts'
 export * as nip44 from './nip44.ts'
 export * as nip47 from './nip47.ts'
 export * as nip57 from './nip57.ts'
+export * as nip59 from './nip59.ts'
 export * as nip98 from './nip98.ts'
 
 export * as kinds from './kinds.ts'

kinds.ts

@@ -48,6 +48,7 @@ export const ChannelMessage = 42
 export const ChannelHideMessage = 43
 export const ChannelMuteUser = 44
 export const OpenTimestamps = 1040
+export const GiftWrap = 1059
 export const FileMetadata = 1063
 export const LiveChatMessage = 1311
 export const ProblemTracker = 1971
@@ -73,7 +74,6 @@ export const SearchRelaysList = 10007
 export const InterestsList = 10015
 export const UserEmojiList = 10030
 export const DirectMessageRelaysList = 10050
-export const GiftWrap = 10059
 export const FileServerPreference = 10096
 export const NWCWalletInfo = 13194
 export const LightningPubRPC = 21000

nip59.test.ts

@@ -0,0 +1,49 @@
+import { test, expect } from 'bun:test'
+import { wrapEvent, unwrapEvent } from './nip59.ts'
+import { decode } from './nip19.ts'
+import { getPublicKey } from './pure.ts'
+
+
+const senderPrivateKey = decode(`nsec1p0ht6p3wepe47sjrgesyn4m50m6avk2waqudu9rl324cg2c4ufesyp6rdg`).data
+const recipientPrivateKey = decode(`nsec1uyyrnx7cgfp40fcskcr2urqnzekc20fj0er6de0q8qvhx34ahazsvs9p36`).data
+const recipientPublicKey = getPublicKey(recipientPrivateKey)
+const event = {
+  kind: 1,
+  content: "Are you going to the party tonight?",
+}
+
+const wrapedEvent = wrapEvent(event, senderPrivateKey, recipientPublicKey)
+
+test('wrapEvent', () => {
+  const expected = {
+    content: '', id: '', created_at: 1728537932, kind: 1059, pubkey: '', sig: '', tags: [
+      [
+        "p",
+        "166bf3765ebd1fc55decfe395beff2ea3b2a4e0a8946e7eb578512b555737c99"
+      ]
+    ],
+    [Symbol('verified')]: true,
+  }
+  const result = wrapEvent(event, senderPrivateKey, recipientPublicKey)
+
+  expect(result.kind).toEqual(expected.kind)
+  expect(result.tags).toEqual(expected.tags)
+
+})
+
+test('unwrapEvent', () => {
+  const expected = {
+    kind: 1,
+    content: "Are you going to the party tonight?",
+    pubkey: "611df01bfcf85c26ae65453b772d8f1dfd25c264621c0277e1fc1518686faef9",
+    tags: [],
+  }
+  const result = unwrapEvent(wrapedEvent, recipientPrivateKey)
+
+  expect(result.kind).toEqual(expected.kind)
+  expect(result.content).toEqual(expected.content)
+  expect(result.pubkey).toEqual(expected.pubkey)
+  expect(result.tags).toEqual(expected.tags)
+
+})
+

nip59.ts

@@ -0,0 +1,76 @@
+
+import { EventTemplate, UnsignedEvent, Event } from './core.ts'
+import { getConversationKey, decrypt, encrypt } from './nip44.ts'
+import { getEventHash, generateSecretKey, finalizeEvent, getPublicKey } from './pure.ts'
+import { Seal, GiftWrap } from './kinds.ts'
+
+type Rumor = UnsignedEvent & { id: string }
+
+const TWO_DAYS = 2 * 24 * 60 * 60
+
+const now = () => Math.round(Date.now() / 1000)
+const randomNow = () => Math.round(now() - (Math.random() * TWO_DAYS))
+
+
+const nip44ConversationKey = (privateKey: Uint8Array, publicKey: string) =>
+  getConversationKey(privateKey, publicKey)
+
+const nip44Encrypt = (data: EventTemplate, privateKey: Uint8Array, publicKey: string) =>
+  encrypt(JSON.stringify(data), nip44ConversationKey(privateKey, publicKey))
+
+const nip44Decrypt = (data: Event, privateKey: Uint8Array) =>
+  JSON.parse(decrypt(data.content, nip44ConversationKey(privateKey, data.pubkey)))
+
+export function createRumor(event: Partial<UnsignedEvent>, privateKey: Uint8Array) {
+  const rumor = {
+    created_at: now(),
+    content: "",
+    tags: [],
+    ...event,
+    pubkey: getPublicKey(privateKey),
+  } as any
+
+  rumor.id = getEventHash(rumor)
+
+  return rumor as Rumor
+}
+
+export function createSeal(rumor: Rumor, privateKey: Uint8Array, recipientPublicKey: string) {
+  return finalizeEvent(
+    {
+      kind: Seal,
+      content: nip44Encrypt(rumor, privateKey, recipientPublicKey),
+      created_at: randomNow(),
+      tags: [],
+    },
+    privateKey
+  ) as Event
+}
+
+export function createWrap(seal: Event, recipientPublicKey: string) {
+  const randomKey = generateSecretKey()
+
+  return finalizeEvent(
+    {
+      kind: GiftWrap,
+      content: nip44Encrypt(seal, randomKey, recipientPublicKey),
+      created_at: randomNow(),
+      tags: [["p", recipientPublicKey]],
+    },
+    randomKey
+  ) as Event
+}
+
+export function wrapEvent(event: Partial<UnsignedEvent>, senderPrivateKey: Uint8Array, recipientPublicKey: string) {
+
+  const rumor = createRumor(event, senderPrivateKey)
+
+  const seal = createSeal(rumor, senderPrivateKey, recipientPublicKey)
+  return createWrap(seal, recipientPublicKey)
+}
+
+export function unwrapEvent(wrap: Event, recipientPrivateKey: Uint8Array) {
+
+  const unwrappedSeal = nip44Decrypt(wrap, recipientPrivateKey)
+  return nip44Decrypt(unwrappedSeal, recipientPrivateKey)
+}