public class LoginManager : IEntityLoginManager
    {
        #region IEntityLoginManager Implementation
 
        public IPrincipal Login(ILoginCredential credential, EntityManager entityManager)               
        {            
            entityManager.VerifierEngine.ErrorsResourceManager = i18n.Localization.ErrorMessages.ResourceManager;
 
            if (credential == null)
                throw new LoginException(LoginExceptionType.NoCredentials, "Credentials are required.");
 
            if (string.IsNullOrWhiteSpace(credential.UserName))
                throw new LoginException(LoginExceptionType.InvalidUserName, "Username cannot be empty.");
 
            if (string.IsNullOrWhiteSpace(credential.Password))
                throw new LoginException(LoginExceptionType.InvalidPassword, "Password cannot be empty.");
 
            var em = new CrmallEntities(entityManager);
 
            var result = em.PersonUsers.Where(u => u.Login.ToUpper() == credential.UserName.ToUpper()
                                            && u.Password == credential.Password)
                                            .Include(f => f.Person)
                                            .Include(f => f.PersonUserProfile)
                                            .Include("PersonUserProfile.SysLanguage")
                                            .Include("PersonUserProfile.SysTimeZoneInfo")
                                            .Execute();
            PersonUser user = result.FirstOrDefault();
            if (user == null)
                throw new LoginException(LoginExceptionType.InvalidPassword, credential.Domain, credential.UserName);
 
            AppDateTime.Initialize();
 
            AuditManager.AuditLogon(em, user);
 
            return user;
        }
 
        public void Logout(IPrincipal principal, EntityManager entityManager)        
        {
            AuditManager.AuditLogoff(new CrmallEntities(entityManager), principal as PersonUser);
 
            entityManager.RejectChanges();
        }

}