func (c *ConfigWriter) PrintSecretSummary() error {
	if c.ztunnelDump == nil {
		return fmt.Errorf("config writer has not been primed")
	}
	secretDump := c.ztunnelDump.Certificates
	w := new(tabwriter.Writer).Init(c.Stdout, 0, 8, 5, ' ', 0)
	fmt.Fprintln(w, "CERTIFICATE NAME\tTYPE\tSTATUS\tVALID CERT\tSERIAL NUMBER\tNOT AFTER\tNOT BEFORE")

	for _, secret := range secretDump {
		if strings.Contains(secret.State, "Unavailable") {

	// XdsPodPort is a port exposing XDS (typically 15010 or 15012)
	XdsPodPort int

	// CertDir is the local directory containing certificates
	CertDir string

	// Timeout is how long to wait before giving up on XDS
	Timeout time.Duration

	// InsecureSkipVerify skips client verification the server's certificate chain and host name.
	InsecureSkipVerify bool

	// XDSSAN is the expected Subject Alternative Name of the XDS server

  # (This is the usual way to get the debug information with an in-cluster control plane.)
  istioctl x internal-debug syncz

  # Retrieve syncz debug information directly from the control plane, using RSA certificate security
  # (Certificates must be obtained before this step.  The --cert-dir flag lets istioctl bypass the Kubernetes API server.)
  istioctl x internal-debug syncz --xds-address istio.example.com:15012 --cert-dir ~/.istio-certs

  # (This is the usual way to get the proxy-status with an in-cluster control plane.)
  istioctl proxy-status

  # Retrieve proxy status information directly from the control plane, using RSA certificate security
  # (Certificates must be obtained before this step.  The --cert-dir flag lets istioctl bypass the Kubernetes API server.)
  istioctl ps --xds-address istio.example.com:15012 --cert-dir ~/.istio-certs

	Ports     map[string]int `json:"ports"`
}

type ZtunnelDump struct {
	Workloads    map[string]*ZtunnelWorkload `json:"by_addr"`
	Services     map[string]*ZtunnelService  `json:"by_vip"`
	Certificates []*CertsDump                `json:"certificates"`
}

type CertsDump struct {
	Identity  string  `json:"identity"`
	State     string  `json:"state"`
	CertChain []*Cert `json:"cert_chain"`
}

type Cert struct {

	common := new(commonFlags)
	cmd := &cobra.Command{
		Use:   "certificate",
		Short: "Retrieves certificate for the specified Ztunnel pod.",
		Long:  `Retrieve information about certificates for the Ztunnel instance.`,
		Example: `  # Retrieve summary about workload configuration for a randomly chosen ztunnel.
  istioctl x ztunnel-config certificates

  # Retrieve full certificate dump of workloads for a given Ztunnel instance.

	Workloads     map[string]*ZtunnelWorkload `json:"workloads"`
	Services      map[string]*ZtunnelService  `json:"services"`
	Policies      map[string]*ZtunnelPolicy   `json:"policies"`
	Certificates  []*CertsDump                `json:"certificates"`
	WorkloadState map[string]WorkloadState    `json:"workloadState"`
}

type CertsDump struct {
	Identity  string  `json:"identity"`
	State     string  `json:"state"`

			s.Name, s.Type, s.State, s.Valid, s.SerialNumber, s.NotAfter, s.NotBefore)
	}
	return tw.Flush()
}

// printSecretItemsJSON prints secret in JSON format, and dumps the raw certificate data with the output
func (w *sdsWriter) printSecretItemsJSON(secrets []SecretItem) error {
	out, err := json.MarshalIndent(secrets, "", " ")
	if err != nil {
		return err
	}

	_, err = w.w.Write(out)

		// TODO: https://github.com/istio/istio/issues/41937
		grpc.WithTransportCredentials(credentials.NewTLS(
			&tls.Config{
				// Always skip verifying, because without it we always get "certificate signed by unknown authority".
				// We don't set the XDSSAN for the same reason.
				InsecureSkipVerify: true,
			})),
		grpc.WithPerRPCCredentials(k8sCreds),
	}, nil

  # (This is the usual way to get the control plane version with an in-cluster control plane.)
  istioctl x version

  # Retrieve version information directly from the control plane, using RSA certificate security
  # (Certificates must be obtained before this step.  The --cert-dir flag lets istioctl bypass the Kubernetes API server.)
  istioctl x version --xds-address istio.example.com:15012 --cert-dir ~/.istio-certs