feat: move all remaining inline logic from routers to services (Tier 2)

backend/app/services/notification_service.py

@@ -13,6 +13,7 @@ from datetime import datetime, timedelta
 from sqlalchemy.orm import Session
 from sqlalchemy import func
 
+from app.domain.errors import EntityNotFoundError
 from app.models.notification import Notification
 from app.models.user import User
 
@@ -22,6 +23,71 @@ from app.models.user import User
 # ---------------------------------------------------------------------------
 
 
+def list_notifications(
+    db: Session,
+    user_id: uuid.UUID,
+    *,
+    offset: int = 0,
+    limit: int = 20,
+) -> list[Notification]:
+    """Return paginated notifications for a user, newest first."""
+    return (
+        db.query(Notification)
+        .filter(Notification.user_id == user_id)
+        .order_by(Notification.created_at.desc())
+        .offset(offset)
+        .limit(limit)
+        .all()
+    )
+
+
+def get_notification_or_raise(
+    db: Session,
+    notification_id: uuid.UUID,
+    user_id: uuid.UUID,
+) -> Notification:
+    """Fetch a notification by ID and user, or raise EntityNotFoundError."""
+    notif = (
+        db.query(Notification)
+        .filter(
+            Notification.id == notification_id,
+            Notification.user_id == user_id,
+        )
+        .first()
+    )
+    if notif is None:
+        raise EntityNotFoundError("Notification", str(notification_id))
+    return notif
+
+
+def notify_role(
+    db: Session,
+    *,
+    role: str,
+    type: str,
+    title: str,
+    message: str,
+    entity_type: str,
+    entity_id: uuid.UUID,
+) -> None:
+    """Send notifications to all active users with a given role."""
+    users = (
+        db.query(User)
+        .filter(User.role == role, User.is_active == True)  # noqa: E712
+        .all()
+    )
+    for user in users:
+        create_notification(
+            db,
+            user_id=user.id,
+            type=type,
+            title=title,
+            message=message,
+            entity_type=entity_type,
+            entity_id=entity_id,
+        )
+
+
 def create_notification(
     db: Session,
     user_id: uuid.UUID,
@@ -45,17 +111,13 @@ def create_notification(
     return notif
 
 
-def mark_as_read(db: Session, notification_id: uuid.UUID, user_id: uuid.UUID) -> bool:
-    """Mark a single notification as read. Returns True if updated."""
-    notif = (
-        db.query(Notification)
-        .filter(Notification.id == notification_id, Notification.user_id == user_id)
-        .first()
-    )
-    if notif is None:
-        return False
+def mark_as_read(
+    db: Session, notification_id: uuid.UUID, user_id: uuid.UUID
+) -> Notification:
+    """Mark a single notification as read. Returns the notification. Raises EntityNotFoundError if not found."""
+    notif = get_notification_or_raise(db, notification_id, user_id)
     notif.read = True
-    return True
+    return notif
 
 
 def mark_all_as_read(db: Session, user_id: uuid.UUID) -> int: