refactor(domain): algebraic NotificationKind — invalid states now unrepresentable

crates/application/src/services/notification_event.rs

@@ -2,9 +2,9 @@ use chrono::Utc;
 use domain::{
     errors::DomainError,
     events::DomainEvent,
-    models::notification::{Notification, NotificationType},
+    models::notification::{Notification, NotificationKind},
     ports::{NotificationRepository, ThoughtRepository},
-    value_objects::{NotificationId, UserId},
+    value_objects::NotificationId,
 };
 use std::sync::Arc;
 
@@ -13,7 +13,10 @@ pub struct NotificationEventService {
     pub notifications: Arc<dyn NotificationRepository>,
 }
 
-fn is_self_action(thought_author: &UserId, actor: &UserId) -> bool {
+fn is_self_action(
+    thought_author: &domain::value_objects::UserId,
+    actor: &domain::value_objects::UserId,
+) -> bool {
     thought_author == actor
 }
 
@@ -36,9 +39,10 @@ impl NotificationEventService {
                     .save(&Notification {
                         id: NotificationId::new(),
                         user_id: thought.user_id,
-                        notification_type: NotificationType::Like,
-                        from_user_id: Some(user_id.clone()),
-                        thought_id: Some(thought_id.clone()),
+                        kind: NotificationKind::Like {
+                            thought_id: thought_id.clone(),
+                            from_user_id: user_id.clone(),
+                        },
                         read: false,
                         created_at: Utc::now(),
                     })
@@ -60,9 +64,10 @@ impl NotificationEventService {
                     .save(&Notification {
                         id: NotificationId::new(),
                         user_id: thought.user_id,
-                        notification_type: NotificationType::Boost,
-                        from_user_id: Some(user_id.clone()),
-                        thought_id: Some(thought_id.clone()),
+                        kind: NotificationKind::Boost {
+                            thought_id: thought_id.clone(),
+                            from_user_id: user_id.clone(),
+                        },
                         read: false,
                         created_at: Utc::now(),
                     })
@@ -76,9 +81,9 @@ impl NotificationEventService {
                     .save(&Notification {
                         id: NotificationId::new(),
                         user_id: following_id.clone(),
-                        notification_type: NotificationType::Follow,
-                        from_user_id: Some(follower_id.clone()),
-                        thought_id: None,
+                        kind: NotificationKind::Follow {
+                            from_user_id: follower_id.clone(),
+                        },
                         read: false,
                         created_at: Utc::now(),
                     })
@@ -104,9 +109,10 @@ impl NotificationEventService {
                     .save(&Notification {
                         id: NotificationId::new(),
                         user_id: original.user_id,
-                        notification_type: NotificationType::Reply,
-                        from_user_id: Some(user_id.clone()),
-                        thought_id: Some(thought_id.clone()),
+                        kind: NotificationKind::Reply {
+                            thought_id: thought_id.clone(),
+                            from_user_id: user_id.clone(),
+                        },
                         read: false,
                         created_at: Utc::now(),
                     })
@@ -121,9 +127,10 @@ impl NotificationEventService {
                     .save(&Notification {
                         id: NotificationId::new(),
                         user_id: mentioned_user_id.clone(),
-                        notification_type: NotificationType::Mention,
-                        from_user_id: Some(author_user_id.clone()),
-                        thought_id: Some(thought_id.clone()),
+                        kind: NotificationKind::Mention {
+                            thought_id: thought_id.clone(),
+                            from_user_id: author_user_id.clone(),
+                        },
                         read: false,
                         created_at: Utc::now(),
                     })
@@ -139,6 +146,7 @@ mod tests {
     use super::*;
     use domain::{
         models::{
+            notification::NotificationKind,
             thought::{Thought, Visibility},
             user::User,
         },
@@ -184,10 +192,7 @@ mod tests {
         .unwrap();
         let notifs = store.notifications.lock().unwrap();
         assert_eq!(notifs.len(), 1);
-        assert!(matches!(
-            notifs[0].notification_type,
-            NotificationType::Like
-        ));
+        assert!(matches!(notifs[0].kind, NotificationKind::Like { .. }));
     }
 
     #[tokio::test]
@@ -235,10 +240,7 @@ mod tests {
         .unwrap();
         let notifs = store.notifications.lock().unwrap();
         assert_eq!(notifs.len(), 1);
-        assert!(matches!(
-            notifs[0].notification_type,
-            NotificationType::Follow
-        ));
+        assert!(matches!(notifs[0].kind, NotificationKind::Follow { .. }));
     }
 
     #[tokio::test]
@@ -269,10 +271,7 @@ mod tests {
         .unwrap();
         let notifs = store.notifications.lock().unwrap();
         assert_eq!(notifs.len(), 1);
-        assert!(matches!(
-            notifs[0].notification_type,
-            NotificationType::Reply
-        ));
+        assert!(matches!(notifs[0].kind, NotificationKind::Reply { .. }));
     }
 
     #[tokio::test]