Improve NIP-05 display in mentions

src/transmute.ts

@@ -4,6 +4,7 @@ import { type MetaContent, parseContent } from '@/schema.ts';
 
 import { LOCAL_DOMAIN } from './config.ts';
 import { getAuthor } from './client.ts';
+import { type Nip05, parseNip05 } from './utils.ts';
 
 const DEFAULT_AVATAR = 'https://gleasonator.com/images/avi.png';
 
@@ -13,9 +14,16 @@ function toAccount(event: Event<0>) {
   const { origin } = new URL(LOCAL_DOMAIN);
   const npub = nip19.npubEncode(pubkey);
 
+  let parsed05: Nip05 | undefined;
+  try {
+    parsed05 = parseNip05(nip05!);
+  } catch (_e) {
+    //
+  }
+
   return {
     id: pubkey,
-    acct: nip05 || npub,
+    acct: parsed05?.handle || npub,
     avatar: picture || DEFAULT_AVATAR,
     avatar_static: picture || DEFAULT_AVATAR,
     bot: false,
@@ -31,9 +39,9 @@ function toAccount(event: Event<0>) {
     header_static: banner,
     locked: false,
     note: about,
-    fqn: nip05 || npub,
+    fqn: parsed05?.handle || npub,
     url: `${origin}/users/${pubkey}`,
-    username: nip05 ? nip05.split('@')[0] : npub,
+    username: parsed05?.nickname || npub,
   };
 }
 

src/utils.ts

@@ -47,4 +47,32 @@ function bech32ToPubkey(bech32: string): string | undefined {
   }
 }
 
-export { bech32ToPubkey, eventDateComparator, getKeys, isBech32, isNostrId, nostrNow };
+interface Nip05 {
+  /** Localpart of the nip05, eg `alex` in `alex@alexgleason.me`. */
+  local: string | undefined;
+  /** Domain of the nip05, eg `alexgleason.me` in `alex@alexgleason.me`. */
+  domain: string;
+  /** Value with underscore removed, eg `_@fiatjaf.com` becomes `fiatjaf.com`, but `alex@alexgleason.me` stays the same. */
+  handle: string;
+  /** The localpart, if available and not `_`. Otherwise the domain. */
+  nickname: string;
+}
+
+/**
+ * Parse a NIP-05 identifier and return an object with metadata about it.
+ * Throws if the value is not a valid NIP-05 identifier.
+ */
+function parseNip05(value: string): Nip05 {
+  const match = value.match(/^(?:([\w.+-]+)@)?([\w.-]+)$/i);
+  if (!match) throw new Error(`nip05: failed to parse ${value}`);
+
+  const [_, local, domain] = match;
+  return {
+    local,
+    domain,
+    handle: local === '_' ? domain : value,
+    nickname: (local && local !== '_') ? local : domain,
+  };
+}
+
+export { bech32ToPubkey, eventDateComparator, getKeys, isBech32, isNostrId, type Nip05, nostrNow, parseNip05 };