ISearchableContentType and Group Members

public int[] GetViewSecurityRoles(Guid contentId)
{
    try
    {
        var content = _roadTestItemService.Get(contentId);
        RoadTestItemApplication app = (RoadTestItemApplication)content.Application;

        IRoles roles = Apis.Get<IRoles>();
        
        List<int?> list = new List<int?>();
        foreach (var role in roles.List(content.ApplicationId, RoadTestConstants.PermissionItemView))
            list.Add(role.Id);
        
        int?[] array = list.Intersect(roles.List(content.Application.Container.ContainerId, (Guid)GroupPermission.ReadGroup)
            .Select(groupRole => groupRole.Id).ToArray()).ToArray();
        
        return array.Select(roleId => Convert.ToInt32(roleId)).ToArray();
    }
    catch (Exception e)
    {
        ExceptionHelper.Handle(e);
        return Array.Empty<int>();
    }
}