protected override void OnValidate()

in src/Microsoft.Azure.NotificationHubs/ApnsCredential.cs [259:318]
53 lines of code
18 McCabe index (conditional complexity)

        protected override void OnValidate(bool allowLocalMockPns)
        {
            if (this.Properties == null)
            {
                throw new InvalidDataContractException(SRClient.ApnsRequiredPropertiesError);
            }

            if (string.IsNullOrWhiteSpace(this.Endpoint))
            {
                throw new InvalidDataContractException(SRClient.ApnsEndpointNotSpecified);
            }

            if (string.IsNullOrWhiteSpace(this.Token) && string.IsNullOrWhiteSpace(this.ApnsCertificate))
            {
                throw new InvalidDataContractException(SRClient.ApnsPropertiesNotSpecified);
            }

            if (!string.IsNullOrWhiteSpace(this.Token) && !string.IsNullOrWhiteSpace(this.ApnsCertificate))
            {
                throw new InvalidDataContractException(SRClient.ApnsProvideOnlyOneCredentialType);
            }

            if (!string.IsNullOrWhiteSpace(this.Token) && (string.IsNullOrWhiteSpace(this.KeyId) ||
                                                           string.IsNullOrWhiteSpace(this.AppId) ||
                                                           string.IsNullOrWhiteSpace(this.AppName)))
            {
                throw new InvalidDataContractException(SRClient.ApnsTokenPropertiesMissing);
            }

            if (!string.IsNullOrWhiteSpace(this.Token))
            {
                return;
            }
            try
            {
                this.NativeCertificate = this.CertificateKey == null ? new X509Certificate2(Convert.FromBase64String(this.ApnsCertificate)) : new X509Certificate2(Convert.FromBase64String(this.ApnsCertificate), this.CertificateKey);
                if (!this.NativeCertificate.HasPrivateKey)
                {
                    throw new InvalidDataContractException(SRClient.ApnsCertificatePrivatekeyMissing);
                }

                if (DateTime.UtcNow > this.NativeCertificate.NotAfter)
                {
                    throw new InvalidDataContractException(SRClient.ApnsCertificateExpired);
                }

                if (DateTime.UtcNow < this.NativeCertificate.NotBefore)
                {
                    throw new InvalidDataContractException(SRClient.ApnsCertificateNotValid);
                }
            }
            catch (CryptographicException ex)
            {
                throw new InvalidDataContractException(string.Format(SRClient.ApnsCertificateNotUsable, ex.Message));
            }
            catch (FormatException ex)
            {
                throw new InvalidDataContractException(string.Format(SRClient.ApnsCertificateNotUsable, ex.Message));
            }
        }