some beginnings of nip29 helpers.

nip29.ts

@@ -0,0 +1,60 @@
+import type { Event } from './pure'
+
+export type Group = {
+  id: string
+  name?: string
+  picture?: string
+  about?: string
+  relay?: string
+  public?: boolean
+  open?: boolean
+}
+
+export function parseGroup(event: Event): Group {
+  const chan: Partial<Group> = {}
+  for (let i = 0; i < event.tags.length; i++) {
+    const tag = event.tags[i]
+    switch (tag[0]) {
+      case 'd':
+        chan.id = tag[1] || ''
+        break
+      case 'name':
+        chan.name = tag[1] || ''
+        break
+      case 'about':
+        chan.about = tag[1] || ''
+        break
+      case 'picture':
+        chan.picture = tag[1] || ''
+        break
+      case 'open':
+        chan.open = true
+        break
+      case 'public':
+        chan.public = true
+        break
+    }
+  }
+  return chan as Group
+}
+
+export type Member = {
+  pubkey: string
+  label?: string
+  permissions: string[]
+}
+
+export function parseMembers(event: Event): Member[] {
+  const members = []
+  for (let i = 0; i < event.tags.length; i++) {
+    const tag = event.tags[i]
+    if (tag.length < 2) continue
+    if (tag[0] !== 'p') continue
+    if (!tag[1].match(/^[0-9a-f]{64}$/)) continue
+    const member: Member = { pubkey: tag[1], permissions: [] }
+    if (tag.length > 2) member.label = tag[2]
+    if (tag.length > 3) member.permissions = tag.slice(3)
+    members.push(member)
+  }
+  return members
+}