public void AddAwardToUser(Guid userId, Guid awardId)
{
Award award = awards.Find(x => x.id == awardId);
if (award == null)
{
throw new ArgumentOutOfRangeException($"No award with {awardId} found");
}
User user = users.Find(x => x.id == userId);
if (user == null)
{
throw new ArgumentOutOfRangeException($"No user with {userId} found");
}
if (user.GetAwards().Contains(awardId))
{
throw new ArgumentException($"User with {userId} already has award with {awardId}");
}
award.AddOwner(userId);
user.AddAward(awardId);
}