public IEnumerable <string> Errors(ChatMessage chat)
{
if (_checkList.HasFlag(CheckList.UserId) && chat.UserGuid != default)
{
yield return("UserId should exist.");
}
if (_checkList.HasFlag(CheckList.Content) && string.IsNullOrEmpty(chat.Content))
{
yield return("Content can't be empty or null.");
}
if (_checkList.HasFlag(CheckList.ValidUserName) && !IsUsernameValid(chat.UserName))
{
yield return("Invalid username format.");
}
if (_checkList.HasFlag(CheckList.ValidRegistration))
{
bool isValidRegistration = chat.Command == Command.REQ_REGISTER_USERNAME &&
IsUsernameValid(chat.UserName);
if (!isValidRegistration)
{
yield return("Invalid registration command");
}
}
if (_checkList.HasFlag(CheckList.ValidExit))
{
bool isValidExit = chat.Command == Command.REQ_END_SESSION &&
IsUsernameValid(chat.UserName);
if (!isValidExit)
{
yield return("Invalid exit command");
}
}
yield break;
}
