Add account lookup endpoint

src/utils.ts

@@ -1,4 +1,4 @@
-import { Context, getPublicKey } from '@/deps.ts';
+import { Context, getPublicKey, nip19, nip21 } from '@/deps.ts';
 import { type Event } from '@/event.ts';
 
 /** Get the current time in Nostr format. */
@@ -21,4 +21,30 @@ function getKeys(c: Context) {
   }
 }
 
-export { eventDateComparator, getKeys, nostrNow };
+/** Return true if the value is a bech32 string, eg for use with NIP-19. */
+function isBech32(value: unknown): value is string {
+  return typeof value === 'string' && nip21.BECH32_REGEX.test(value);
+}
+
+/** Return true if the value is a Nostr pubkey, private key, or event ID. */
+function isNostrId(value: unknown): value is string {
+  return typeof value === 'string' && /^[0-9a-f]{64}$/.test(value);
+}
+
+/** Get pubkey from bech32 string, if applicable. */
+function bech32ToPubkey(bech32: string): string | undefined {
+  try {
+    const decoded = nip19.decode(bech32);
+
+    switch (decoded.type) {
+      case 'nprofile':
+        return decoded.data.pubkey;
+      case 'npub':
+        return decoded.data;
+    }
+  } catch (_) {
+    //
+  }
+}
+
+export { bech32ToPubkey, eventDateComparator, getKeys, isBech32, isNostrId, nostrNow };