fix: remote actor display names in thought cards — use last URL segment as username, resolve display_name after intern

crates/adapters/postgres/src/activitypub.rs

@@ -154,13 +154,18 @@ impl ActivityPubRepository for PgActivityPubRepository {
             return Ok(id);
         }
         let new_id = uuid::Uuid::new_v4();
-        let raw = actor_ap_url
-            .path()
-            .trim_start_matches('/')
-            .replace('/', "_");
-        // username column is VARCHAR(32); truncate long paths (e.g. UUID-based actor URLs)
-        let handle = if raw.len() <= 32 {
-            raw
+        // Use the last path segment as username (e.g. /users/alice → "alice").
+        // Falls back to a random short id for long segments (e.g. UUID-based actor URLs).
+        // username column is VARCHAR(32).
+        let last_seg = actor_ap_url
+            .path_segments()
+            .and_then(|mut s| s.next_back())
+            .unwrap_or("")
+            .to_string();
+        let handle = if last_seg.is_empty() {
+            format!("remote_{}", &new_id.to_string()[..13])
+        } else if last_seg.len() <= 32 {
+            last_seg
         } else {
             format!("remote_{}", &new_id.to_string()[..13])
         };
@@ -185,6 +190,25 @@ impl ActivityPubRepository for PgActivityPubRepository {
             })
     }
 
+    async fn update_remote_actor_display(
+        &self,
+        user_id: &UserId,
+        display_name: Option<&str>,
+        avatar_url: Option<&str>,
+    ) -> Result<(), DomainError> {
+        sqlx::query(
+            "UPDATE users SET display_name=$1, avatar_url=$2, updated_at=NOW()
+             WHERE id=$3 AND local=false",
+        )
+        .bind(display_name)
+        .bind(avatar_url)
+        .bind(user_id.as_uuid())
+        .execute(&self.pool)
+        .await
+        .map_err(|e| DomainError::Internal(e.to_string()))
+        .map(|_| ())
+    }
+
     async fn accept_note(
         &self,
         ap_id: &Url,

crates/application/src/services/federation_event.rs

@@ -136,6 +136,22 @@ impl FederationEventService {
 
                 let author_id = self.ap_repo.intern_remote_actor(&actor_url).await?;
 
+                // Resolve and cache display info so thought cards show proper names.
+                let profiles = self
+                    .federation_action
+                    .resolve_actor_profiles(vec![actor_ap_url.clone()])
+                    .await;
+                if let Some(profile) = profiles.into_iter().next() {
+                    let _ = self
+                        .ap_repo
+                        .update_remote_actor_display(
+                            &author_id,
+                            profile.display_name.as_deref(),
+                            profile.avatar_url.as_deref(),
+                        )
+                        .await;
+                }
+
                 for note in notes {
                     let ap_id = match url::Url::parse(&note.ap_id) {
                         Ok(u) => u,

crates/domain/src/ports.rs

@@ -342,6 +342,14 @@ pub trait ActivityPubRepository: Send + Sync {
     /// Idempotent — safe to call multiple times with the same URL.
     async fn intern_remote_actor(&self, actor_ap_url: &url::Url) -> Result<UserId, DomainError>;
 
+    /// Update display_name and avatar_url for an already-interned remote actor.
+    async fn update_remote_actor_display(
+        &self,
+        user_id: &UserId,
+        display_name: Option<&str>,
+        avatar_url: Option<&str>,
+    ) -> Result<(), DomainError>;
+
     // ── Inbox processing (remote → local) ───────────────────────────
 
     /// Persist an incoming remote Note. Idempotent on ap_id.

crates/domain/src/testing.rs

@@ -779,6 +779,14 @@ impl ActivityPubRepository for TestStore {
         self.users.lock().unwrap().push(user);
         Ok(uid)
     }
+    async fn update_remote_actor_display(
+        &self,
+        _user_id: &UserId,
+        _display_name: Option<&str>,
+        _avatar_url: Option<&str>,
+    ) -> Result<(), DomainError> {
+        Ok(())
+    }
     async fn accept_note(
         &self,
         _ap_id: &url::Url,