refactor: standardize @ prefix handling and improve npub/nprofile display

- Fix getNpubFallbackDisplay to return names without @ prefix
- Update all call sites to consistently add @ when rendering mentions
- Fix incomplete error handling in getNpubFallbackDisplay catch block
- Add nprofile support to addLoadingClassToProfileLinks
- Extract shared isProfileInCacheOrStore utility to eliminate duplicate loading state checks
- Update ResolvedMention and NostrMentionLink to use shared utility

This ensures consistent @ prefix handling across all profile display contexts
and eliminates code duplication for profile loading state detection.

src/components/NostrMentionLink.tsx

@@ -4,7 +4,7 @@ import { useEventModel } from 'applesauce-react/hooks'
 import { Hooks } from 'applesauce-react'
 import { Models, Helpers } from 'applesauce-core'
 import { getProfileDisplayName } from '../utils/nostrUriResolver'
-import { loadCachedProfiles } from '../services/profileService'
+import { isProfileInCacheOrStore } from '../utils/profileLoadingUtils'
 
 const { getPubkeyFromDecodeResult } = Helpers
 
@@ -43,14 +43,7 @@ const NostrMentionLink: React.FC<NostrMentionLinkProps> = ({
   // Check if profile is in cache or eventStore for loading detection
   const isInCacheOrStore = useMemo(() => {
     if (!pubkey) return false
-    // Check cache
-    const cached = loadCachedProfiles([pubkey])
-    if (cached.has(pubkey)) {
-      return true
-    }
-    // Check eventStore
-    const eventStoreProfile = eventStore?.getEvent(pubkey + ':0')
-    return !!eventStoreProfile
+    return isProfileInCacheOrStore(pubkey, eventStore)
   }, [pubkey, eventStore])
   
   // Show loading if profile doesn't exist and not in cache/store (for npub/nprofile)

src/components/ResolvedMention.tsx

@@ -5,7 +5,7 @@ import { Hooks } from 'applesauce-react'
 import { Models, Helpers } from 'applesauce-core'
 import { decode, npubEncode } from 'nostr-tools/nip19'
 import { getProfileDisplayName } from '../utils/nostrUriResolver'
-import { loadCachedProfiles } from '../services/profileService'
+import { isProfileInCacheOrStore } from '../utils/profileLoadingUtils'
 
 const { getPubkeyFromDecodeResult } = Helpers
 
@@ -28,14 +28,7 @@ const ResolvedMention: React.FC<ResolvedMentionProps> = ({ encoded }) => {
   // Check if profile is in cache or eventStore
   const isInCacheOrStore = useMemo(() => {
     if (!pubkey) return false
-    // Check cache
-    const cached = loadCachedProfiles([pubkey])
-    if (cached.has(pubkey)) {
-      return true
-    }
-    // Check eventStore
-    const eventStoreProfile = eventStore?.getEvent(pubkey + ':0')
-    return !!eventStoreProfile
+    return isProfileInCacheOrStore(pubkey, eventStore)
   }, [pubkey, eventStore])
   
   // Show loading if profile doesn't exist and not in cache/store

src/hooks/useProfileLabels.ts

@@ -60,13 +60,13 @@ export function useProfileLabels(
       if (cachedProfile) {
         const displayName = extractProfileDisplayName(cachedProfile)
         if (displayName) {
-          // Only add @ prefix if we have a real name, otherwise use fallback format directly
-          const label = displayName.startsWith('@') ? displayName : `@${displayName}`
+          // Add @ prefix (extractProfileDisplayName returns name without @)
+          const label = `@${displayName}`
           labels.set(pubkey, label)
         } else {
-          // Use fallback npub display if profile has no name
+          // Use fallback npub display if profile has no name (add @ prefix)
           const fallback = getNpubFallbackDisplay(pubkey)
-          labels.set(pubkey, fallback)
+          labels.set(pubkey, `@${fallback}`)
         }
       }
     })
@@ -224,13 +224,13 @@ export function useProfileLabels(
         // Extract display name using centralized utility
         const displayName = extractProfileDisplayName(eventStoreProfile as NostrEvent)
         if (displayName) {
-          // Only add @ prefix if we have a real name, otherwise use fallback format directly
-          const label = displayName.startsWith('@') ? displayName : `@${displayName}`
+          // Add @ prefix (extractProfileDisplayName returns name without @)
+          const label = `@${displayName}`
           labels.set(pubkey, label)
         } else {
-          // Use fallback npub display if profile has no name
+          // Use fallback npub display if profile has no name (add @ prefix)
           const fallback = getNpubFallbackDisplay(pubkey)
-          labels.set(pubkey, fallback)
+          labels.set(pubkey, `@${fallback}`)
         }
         loading.set(pubkey, false)
       } else {
@@ -258,8 +258,9 @@ export function useProfileLabels(
         const pubkey = event.pubkey
         
         // Determine the label for this profile using centralized utility
+        // Add @ prefix (both extractProfileDisplayName and getNpubFallbackDisplay return names without @)
         const displayName = extractProfileDisplayName(event)
-        const label = displayName ? (displayName.startsWith('@') ? displayName : `@${displayName}`) : getNpubFallbackDisplay(pubkey)
+        const label = displayName ? `@${displayName}` : `@${getNpubFallbackDisplay(pubkey)}`
         
         // Apply label immediately to prevent race condition with loading state
         // This ensures labels are available when isLoading becomes false

src/utils/nostrUriResolver.tsx

@@ -86,13 +86,15 @@ export function getNostrUriLabel(encoded: string): string {
     const decoded = decode(encoded)
     
     switch (decoded.type) {
-      case 'npub':
-        // Remove "npub1" prefix (5 chars) and show next 7 chars
-        return `@${encoded.slice(5, 12)}...`
+      case 'npub': {
+        // Use shared fallback display function and add @ for label
+        const pubkey = decoded.data
+        return `@${getNpubFallbackDisplay(pubkey)}`
+      }
       case 'nprofile': {
-        const npub = npubEncode(decoded.data.pubkey)
-        // Remove "npub1" prefix (5 chars) and show next 7 chars
-        return `@${npub.slice(5, 12)}...`
+        // Use shared fallback display function and add @ for label
+        const pubkey = decoded.data.pubkey
+        return `@${getNpubFallbackDisplay(pubkey)}`
       }
       case 'note':
         return `note:${encoded.slice(5, 12)}...`
@@ -119,18 +121,19 @@ export function getNostrUriLabel(encoded: string): string {
 
 /**
  * Get a standardized fallback display name for a pubkey when profile has no name
- * Returns npub format: @abc1234...
+ * Returns npub format: abc1234... (without @ prefix)
+ * Components should add @ prefix when rendering mentions/links
  * @param pubkey The pubkey in hex format
- * @returns Formatted npub display string
+ * @returns Formatted npub display string without @ prefix
  */
 export function getNpubFallbackDisplay(pubkey: string): string {
   try {
     const npub = npubEncode(pubkey)
     // Remove "npub1" prefix (5 chars) and show next 7 chars
-    return `@${npub.slice(5, 12)}...`
+    return `${npub.slice(5, 12)}...`
   } catch {
     // Fallback to shortened pubkey if encoding fails
-    return `@${pubkey.slice(0, 8)}...`
+    return `${pubkey.slice(0, 8)}...`
   }
 }
 
@@ -380,12 +383,17 @@ export function addLoadingClassToProfileLinks(
   // Find all <a> tags with href starting with /p/ (profile links)
   const result = html.replace(/<a\s+[^>]*?href="\/p\/([^"]+)"[^>]*?>/g, (match, npub: string) => {
     try {
-      // Decode npub to get pubkey
+      // Decode npub or nprofile to get pubkey
       const decoded: ReturnType<typeof decode> = decode(npub)
-      switch (decoded.type) {
-        case 'npub': {
-          const pubkey = decoded.data
       
+      let pubkey: string | undefined
+      if (decoded.type === 'npub') {
+        pubkey = decoded.data
+      } else if (decoded.type === 'nprofile') {
+        pubkey = decoded.data.pubkey
+      }
+      
+      if (pubkey) {
         // Check if this profile is loading
         const isLoading = profileLoading.get(pubkey)
         
@@ -403,11 +411,6 @@ export function addLoadingClassToProfileLinks(
             }
           }
         }
-          break
-        }
-        default:
-          // Not an npub, ignore
-          break
       }
     } catch (error) {
       // Ignore processing errors

src/utils/profileLoadingUtils.ts

@@ -0,0 +1,27 @@
+import { IEventStore } from 'applesauce-core'
+import { loadCachedProfiles } from '../services/profileService'
+
+/**
+ * Check if a profile exists in cache or eventStore
+ * Used to determine if profile loading state should be shown
+ * @param pubkey The pubkey in hex format
+ * @param eventStore Optional eventStore instance
+ * @returns true if profile exists in cache or eventStore, false otherwise
+ */
+export function isProfileInCacheOrStore(
+  pubkey: string,
+  eventStore?: IEventStore | null
+): boolean {
+  if (!pubkey) return false
+  
+  // Check cache first
+  const cached = loadCachedProfiles([pubkey])
+  if (cached.has(pubkey)) {
+    return true
+  }
+  
+  // Check eventStore
+  const eventStoreProfile = eventStore?.getEvent(pubkey + ':0')
+  return !!eventStoreProfile
+}
+