updated view and database

app/services/device_service.py

@@ -13,8 +13,15 @@ class DeviceService:
     """Service for managing devices and device-related operations"""
     
     def __init__(self):
-        self.db = get_db()
+        self._db = None
         self.logger = logging.getLogger(__name__)
+
+    @property
+    def db(self):
+        """Lazily resolve the database handle (see LogCompressionService.db)."""
+        if self._db is None:
+            self._db = get_db()
+        return self._db
     
     # Basic CRUD Operations
 
@@ -213,7 +220,10 @@ class DeviceService:
                     'recent_logs_24h': recent_logs,
                     'total_files': total_files,
                     'last_log': last_log,
-                    'uptime_days': (datetime.utcnow() - device.last_seen).days if device.last_seen else 0
+                    # Days since the device was last seen (0 = seen today / currently active).
+                    # Previously mislabeled as "uptime_days" which implied the opposite.
+                    'days_since_last_seen': (datetime.utcnow() - device.last_seen).days if device.last_seen else None,
+                    'is_online': device.is_online,
                 }
                 
         except Exception as e: