up

internal/services/screen_service/service.go

@@ -7,6 +7,9 @@ import (
 	"evening_detective_server/internal/repos/screen_sessions_repo"
 )
 
+// ErrInvalidMode indicates an unsupported display mode.
+var ErrInvalidMode = errors.New("некорректный режим экрана")
+
 // ErrScreenNotFound indicates that a screen session was not found.
 var ErrScreenNotFound = errors.New("экран не найден")
 
@@ -47,8 +50,21 @@ func (s *ScreenService) ListByGame(ctx context.Context, gameID int) ([]*ScreenSe
 	return result, nil
 }
 
+// ValidMode reports whether mode is a supported display mode.
+func ValidMode(mode int32) bool {
+	switch mode {
+	case 1, 2, 4, 6, 7, 8:
+		return true
+	default:
+		return false
+	}
+}
+
 // SetMode updates the display mode for a game.
 func (s *ScreenService) SetMode(ctx context.Context, gameID int, mode int32) error {
+	if !ValidMode(mode) {
+		return ErrInvalidMode
+	}
 	return s.repo.SetMode(ctx, gameID, mode)
 }
 

internal/services/screen_service/service_test.go

@@ -0,0 +1,16 @@
+package screen_service
+
+import (
+	"context"
+	"errors"
+	"testing"
+)
+
+func TestSetModeRejectsUnsupportedModes(t *testing.T) {
+	s := NewScreenService(nil)
+	for _, mode := range []int32{-1, 0, 3, 5, 9} {
+		if err := s.SetMode(context.Background(), 1, mode); !errors.Is(err, ErrInvalidMode) {
+			t.Errorf("SetMode(%d) = %v, want ErrInvalidMode", mode, err)
+		}
+	}
+}