CmisSync.CertPolicyWindow.ShowCertDialog C# (CSharp) Method

        private void ShowCertDialog()
        {
            Logger.Debug("Showing Cert Dialog: " + Handler.UserMessage);
            CertPolicyHandler.Response ret = CertPolicyHandler.Response.None;
            using (var signal = new AutoResetEvent(false))
            {
                InvokeOnMainThread(delegate
                {
                    try
                    {
                        NSAlert alert = NSAlert.WithMessage("Untrusted Certificate", "No", "Always", "Just now", Handler.UserMessage + "\n\nDo you trust this certificate?");
                        switch (alert.RunModal())
                        {
                            case 1:
                                ret = CertPolicyHandler.Response.CertDeny;
                                break;
                            case 0:
                                ret = CertPolicyHandler.Response.CertAcceptAlways;
                                break;
                            case -1:
                                ret = CertPolicyHandler.Response.CertAcceptSession;
                                break;
                            default:
                                ret = CertPolicyHandler.Response.None;
                                break;
                        }
                    }
                    catch (Exception)
                    {
                        ret = CertPolicyHandler.Response.None;
                    }
                    finally
                    {
                        signal.Set();
                    }
                });
                signal.WaitOne();
            }
            Logger.Debug("Cert Dialog return:" + ret.ToString());
            Handler.UserResponse = ret;
        }
    }