removed device_id from all entities except car. Replaced with car_id . Car -> device_id

server/internal/lobby/lobby.go

@@ -187,7 +187,7 @@ func (s *Service) RemoveDriver(id string) {
 	d.Status = DriverStatusOffline
 	d.LastSeenMs = time.Now().UnixMilli()
 	d.RaceID = ""
-	d.DeviceID = nil
+	d.CarID = nil
 	hook := s.onRaceRemoved
 	s.mu.Unlock()
 
@@ -244,9 +244,9 @@ func (s *Service) AddDriverToRace(driverID, raceID string) error {
 		s.mu.Unlock()
 		return ErrDriverNotFound
 	}
-	if d.DeviceID == nil {
+	if d.CarID == nil || *d.CarID == "" {
 		s.mu.Unlock()
-		return fmt.Errorf("driver %s has no device selected", driverID)
+		return fmt.Errorf("driver %s has no car selected", driverID)
 	}
 	r, ok := s.races[raceID]
 	if !ok {
@@ -306,7 +306,7 @@ func (s *Service) RemoveDriverFromRace(driverID string) {
 	}
 	d.Status = DriverStatusIdle
 	d.RaceID = ""
-	d.DeviceID = nil
+	d.CarID = nil
 	prevRaceID := d.RaceID
 	hook := s.onRaceRemoved
 	s.mu.Unlock()
@@ -349,7 +349,7 @@ func (s *Service) SetRaceStatus(raceID string, status RaceStatus) error {
 			if d, ok := s.drivers[did]; ok {
 				d.Status = DriverStatusIdle
 				d.RaceID = ""
-				d.DeviceID = nil
+				d.CarID = nil
 				affected = append(affected, *d)
 			}
 		}
@@ -454,16 +454,10 @@ func (s *Service) GetDriver(driverID string) (DriverMeta, error) {
 	return *d, nil
 }
 
-// SelectDevice assigns a physical device ID (0..127) to a driver.
-// Pass deviceID = nil to release the device.
-// Returns an error if the device is already taken by another online driver.
-func (s *Service) SelectDevice(driverID string, deviceID *int) error {
-	if deviceID != nil {
-		if *deviceID < 0 || *deviceID > 127 {
-			return fmt.Errorf("invalid device ID: must be 0..127")
-		}
-	}
-
+// SelectCar assigns a catalog car ID to a driver.
+// If carID is nil, it clears the driver's car assignment.
+// It returns an error if the car is already taken by another active driver.
+func (s *Service) SelectCar(driverID string, carID *string) error {
 	s.mu.Lock()
 	d, ok := s.drivers[driverID]
 	if !ok {
@@ -471,17 +465,17 @@ func (s *Service) SelectDevice(driverID string, deviceID *int) error {
 		return ErrDriverNotFound
 	}
 
-	// Enforce that device cannot be selected if already assigned to another driver.
-	if deviceID != nil {
+	// Enforce that car cannot be selected if already assigned to another driver.
+	if carID != nil && *carID != "" {
 		for otherID, otherD := range s.drivers {
-			if otherID != driverID && otherD.Status != DriverStatusOffline && otherD.DeviceID != nil && *otherD.DeviceID == *deviceID {
+			if otherID != driverID && otherD.Status != DriverStatusOffline && otherD.CarID != nil && *otherD.CarID == *carID {
 				s.mu.Unlock()
-				return fmt.Errorf("device %d is already taken by driver %s", *deviceID, otherID)
+				return fmt.Errorf("car %s is already taken by driver %s", *carID, otherID)
 			}
 		}
 	}
 
-	d.DeviceID = deviceID
+	d.CarID = carID
 	out := *d
 	s.mu.Unlock()
 

server/internal/lobby/lobby_test.go

@@ -75,9 +75,9 @@ func TestQuickPlayJoinsFirstRace(t *testing.T) {
 	s := NewService()
 	_, _ = s.AddDriver("d1", "Alice", "")
 	_, _ = s.AddDriver("d2", "Bob", "")
-	dev1, dev2 := 1, 2
-	_ = s.SelectDevice("d1", &dev1)
-	_ = s.SelectDevice("d2", &dev2)
+	car1, car2 := "car-1", "car-2"
+	_ = s.SelectCar("d1", &car1)
+	_ = s.SelectCar("d2", &car2)
 	r1, _ := s.QuickPlay("d1", 4)
 	r2, err := s.QuickPlay("d2", 4)
 	if err != nil {

server/internal/lobby/types.go

@@ -65,7 +65,7 @@ type DriverMeta struct {
 	LastSeenMs  int64        `json:"last_seen_ms"`
 	Country     string       `json:"country,omitempty"` // optional, for UI
 	AvatarHue   int          `json:"avatar_hue,omitempty"` // 0..360, deterministic per id
-	DeviceID    *int         `json:"-"`
+	CarID       *string      `json:"car_id,omitempty"`
 }
 
 // Snapshot is the immutable view broadcast to clients.