public async Task <Models.Contact> SearchUserByUserNameAsync(string userName)
{
string normalizedUserName = userName.TrimStart('@');
Models.Contact contact = SearchContactInLocalCache(c => string.Equals(c.Username, normalizedUserName, StringComparison.CurrentCultureIgnoreCase));
if (contact != null)
{
return(contact);
}
await ConnectAsync();
User resolveUser = await _client.ResolveUsername(normalizedUserName);
return((Models.Contact)resolveUser);
}