// SPDX-License-Identifier: Apache-2.0
// Copyright Authors of Cilium

package check

import (
	"bytes"
	"context"
	_ "embed"
	"fmt"
	"io"
	"net"
	"sync"
	"time"

	"github.com/blang/semver/v4"
	k8sConst "github.com/cilium/cilium/pkg/k8s/apis/cilium.io"
	ciliumv2 "github.com/cilium/cilium/pkg/k8s/apis/cilium.io/v2"
	v2 "github.com/cilium/cilium/pkg/k8s/apis/cilium.io/v2"
	"github.com/cilium/cilium/pkg/versioncheck"

	"github.com/cilium/cilium-cli/defaults"
	"github.com/cilium/cilium-cli/sysdump"

	corev1 "k8s.io/api/core/v1"
	networkingv1 "k8s.io/api/networking/v1"
	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"

	"github.com/cloudflare/cfssl/cli/genkey"
	"github.com/cloudflare/cfssl/config"
	"github.com/cloudflare/cfssl/csr"
	"github.com/cloudflare/cfssl/helpers"
	"github.com/cloudflare/cfssl/initca"
	"github.com/cloudflare/cfssl/signer"
	"github.com/cloudflare/cfssl/signer/local"
)

const (
	// kubernetesSourcedLabelPrefix is the optional prefix used in labels to
	// indicate they are sourced from Kubernetes.
	// NOTE: For some reason, ':' gets replaced by '.' in keys so we use that instead.
	kubernetesSourcedLabelPrefix = "k8s."

	// anySourceLabelPrefix is the optional prefix used in labels to
	// indicate they could be from anywhere.
	// NOTE: For some reason, ':' gets replaced by '.' in keys so we use that instead.
	anySourceLabelPrefix = "any."
)

var (
	//go:embed assets/cacert.pem
	caBundle []byte
)

type Test struct {
	// Reference to the enclosing test suite for logging etc.
	ctx *ConnectivityTest

	// Name of the test. Must be unique within the scope of a test run.
	name string

	// True if the Test is marked as skipped.
	skipped bool

	// True if the Test is marked as failed.
	failed bool

	// requirements is a list of required Cilium features which need to match
	// for this test to be run
	requirements []FeatureRequirement

	// installIPRoutesFromOutsideToPodCIDRs indicates that the test runner needs
	// to install podCIDR => nodeIP routes before running the test
	installIPRoutesFromOutsideToPodCIDRs bool

	// requiredCiliumVSN is a required Cilium VSN for this test to be run
	requiredCiliumVSN semver.Range

	// Scenarios registered to this test.
	scenarios map[Scenario][]*Action

	// Scenarios marked as skipped during execution.
	// Needs to be stored as a list, these are implemented in another package.
	scenariosSkipped []Scenario

	// Policies active during this test.
	cnps map[string]*ciliumv2.CiliumNetworkPolicy

	// Kubernetes Network Policies active during this test.
	knps map[string]*networkingv1.NetworkPolicy

	// Cilium Egress Gateway Policies active during this test.
	cegps map[string]*v2.CiliumEgressGatewayPolicy

	// Secrets that have to be present during the test.
	secrets map[string]*corev1.Secret

	// CA certificates of the certificates that have to be present during the test.
	certificateCAs map[string][]byte

	// List of callbacks to be executed before the test run as additional setup.
	before []SetupFunc

	expectFunc ExpectationsFunc

	// Start time of the test.
	startTime time.Time

	// Completion time of the test.
	completionTime time.Time

	// Buffer to store output until it's flushed by a failure.
	// Unused when run in verbose or debug mode.
	logMu   sync.RWMutex
	logBuf  io.ReadWriter
	warnBuf *bytes.Buffer
	verbose bool

	// List of functions to be called when Run() returns.
	finalizers []func() error
}

func (t *Test) String() string {
	return fmt.Sprintf("<Test %s, %d scenarios, %d CNPs, expectFunc %v>", t.name, len(t.scenarios), len(t.cnps), t.expectFunc)
}

// Name returns the name of the test.
func (t *Test) Name() string {
	return t.name
}

// ScenarioName returns the Test name and Scenario name concatenated in
// a standard way. Scenario names are not unique, as they can occur multiple
// times in the same Test.
func (t *Test) scenarioName(s Scenario) string {
	return fmt.Sprintf("%s/%s", t.Name(), s.Name())
}

// scenarioEnabled returns true if the given scenario is enabled based on the
// set of enabled tests, and if the given scenario also meets the feature
// requirements of the deployed cilium installation
func (t *Test) scenarioEnabled(s Scenario) bool {
	var reqs []FeatureRequirement
	if cs, ok := s.(ConditionalScenario); ok {
		reqs = cs.Requirements()
	}

	return t.Context().params.testEnabled(t.scenarioName(s)) &&
		t.Context().Features.MatchRequirements(reqs...)
}

// Context returns the enclosing context of the Test.
func (t *Test) Context() *ConnectivityTest {
	return t.ctx
}

// setup sets up the environment for the Test to execute in, like applying secrets and CNPs.
func (t *Test) setup(ctx context.Context) error {

	// Apply Secrets to the cluster.
	if err := t.applySecrets(ctx); err != nil {
		t.ciliumLogs(ctx)
		return fmt.Errorf("applying Secrets: %w", err)
	}

	// Apply CNPs & KNPs to the cluster.
	if err := t.applyPolicies(ctx); err != nil {
		t.ciliumLogs(ctx)
		return fmt.Errorf("applying network policies: %w", err)
	}

	if t.installIPRoutesFromOutsideToPodCIDRs {
		if err := t.Context().modifyStaticRoutesForNodesWithoutCilium(ctx, "add"); err != nil {
			return fmt.Errorf("installing static routes: %w", err)
		}

		t.finalizers = append(t.finalizers, func() error {
			return t.Context().modifyStaticRoutesForNodesWithoutCilium(ctx, "del")
		})
	}

	return nil
}

// skip adds Scenario s to the Test's list of skipped Scenarios.
// This list is kept for reporting purposes.
func (t *Test) skip(s Scenario) {
	t.scenariosSkipped = append(t.scenariosSkipped, s)
	t.Logf("[-] Skipping Scenario [%s]", t.scenarioName(s))
}

// willRun returns false if all of the Test's Scenarios will be skipped, or
// if any of its FeatureRequirements does not match, or a required Cilium vsn
// does not match.
func (t *Test) willRun() bool {
	var sc int

	if !t.Context().Features.MatchRequirements(t.requirements...) {
		return false
	}

	if t.requiredCiliumVSN != nil && !t.requiredCiliumVSN(t.Context().CiliumVersion) {
		return false
	}

	for s := range t.scenarios {
		if !t.Context().params.testEnabled(t.scenarioName(s)) {
			sc++
		}
	}

	return sc != len(t.scenarios)
}

// finalize runs all the Test's registered finalizers.
// Failures encountered executing finalizers will fail the Test.
func (t *Test) finalize() {
	t.Debug("Finalizing Test", t.Name())

	for _, f := range t.finalizers {
		if err := f(); err != nil {
			t.Failf("Error finalizing '%s': %s", t.Name(), err)
		}
	}
}

// Run executes all Scenarios registered to the Test.
func (t *Test) Run(ctx context.Context) error {
	if err := ctx.Err(); err != nil {
		return err
	}

	// Steps to execute when all Scenarios have finished executing,
	// whether they were successful or not. Scenario.Run() might call Fatal(),
	// in which case this function executes as normal.
	defer func() {
		// Run all the Test's registered finalizers.
		t.finalize()
	}()

	if len(t.scenarios) == 0 {
		t.Fail("Test has no Scenarios")
	}

	// Skip the Test if all of its Scenarios are skipped.
	if !t.willRun() {
		t.Context().skip(t)
		return nil
	}

	// Store start time of the Test.
	t.startTime = time.Now()
	// Store completion of the Test when function is returned
	defer func() {
		t.completionTime = time.Now()
	}()

	t.ctx.Logf("[=] Test [%s]", t.Name())

	if err := t.setup(ctx); err != nil {
		return fmt.Errorf("setting up test: %w", err)
	}

	for _, cb := range t.before {
		if err := cb(ctx, t, t.ctx); err != nil {
			return fmt.Errorf("additional test setup callback: %w", err)
		}
	}

	if t.logBuf != nil {
		t.ctx.Timestamp()
	}

	for s := range t.scenarios {
		if err := ctx.Err(); err != nil {
			return err
		}

		if !t.scenarioEnabled(s) {
			t.skip(s)
			continue
		}

		t.Logf("[-] Scenario [%s]", t.scenarioName(s))

		s.Run(ctx, t)
	}

	if t.logBuf != nil {
		fmt.Fprintln(t.ctx.params.Writer)
	}

	// Don't add any more code here, as Scenario.Run() can call Fatal() and
	// terminate this goroutine.

	return nil
}

// WithCiliumPolicy takes a string containing a YAML policy document and adds
// the polic(y)(ies) to the scope of the Test, to be applied when the test
// starts running. When calling this method, note that the CNP enabled feature
// // requirement is applied directly here.
func (t *Test) WithCiliumPolicy(policy string) *Test {
	pl, err := parseCiliumPolicyYAML(policy)
	if err != nil {
		t.Fatalf("Parsing policy YAML: %s", err)
	}

	// Change the default test namespace as required.
	for i := range pl {
		pl[i].Namespace = t.ctx.params.TestNamespace
		if pl[i].Spec != nil {
			for _, k := range []string{
				k8sConst.PodNamespaceLabel,
				kubernetesSourcedLabelPrefix + k8sConst.PodNamespaceLabel,
				anySourceLabelPrefix + k8sConst.PodNamespaceLabel,
			} {
				for _, e := range pl[i].Spec.Egress {
					for _, es := range e.ToEndpoints {
						if n, ok := es.MatchLabels[k]; ok && n == defaults.ConnectivityCheckNamespace {
							es.MatchLabels[k] = t.ctx.params.TestNamespace
						}
					}
				}
				for _, e := range pl[i].Spec.Ingress {
					for _, es := range e.FromEndpoints {
						if n, ok := es.MatchLabels[k]; ok && n == defaults.ConnectivityCheckNamespace {
							es.MatchLabels[k] = t.ctx.params.TestNamespace
						}
					}
				}

				for _, e := range pl[i].Spec.EgressDeny {
					for _, es := range e.ToEndpoints {
						if n, ok := es.MatchLabels[k]; ok && n == defaults.ConnectivityCheckNamespace {
							es.MatchLabels[k] = t.ctx.params.TestNamespace
						}
					}
				}

				for _, e := range pl[i].Spec.IngressDeny {
					for _, es := range e.FromEndpoints {
						if n, ok := es.MatchLabels[k]; ok && n == defaults.ConnectivityCheckNamespace {
							es.MatchLabels[k] = t.ctx.params.TestNamespace
						}
					}
				}
			}
		}
	}

	if err := t.addCNPs(pl...); err != nil {
		t.Fatalf("Adding CNPs to policy context: %s", err)
	}

	t.WithFeatureRequirements(RequireFeatureEnabled(FeatureCNP))

	return t
}

// WithK8SPolicy takes a string containing a YAML policy document and adds
// the polic(y)(ies) to the scope of the Test, to be applied when the test
// starts running. When calling this method, note that the KNP enabled feature
// requirement is applied directly here.
func (t *Test) WithK8SPolicy(policy string) *Test {
	pl, err := parseK8SPolicyYAML(policy)
	if err != nil {
		t.Fatalf("Parsing K8S policy YAML: %s", err)
	}

	// Change the default test namespace as required.
	for i := range pl {
		pl[i].Namespace = t.ctx.params.TestNamespace

		if pl[i].Spec.Size() != 0 {
			for _, k := range []string{
				k8sConst.PodNamespaceLabel,
				kubernetesSourcedLabelPrefix + k8sConst.PodNamespaceLabel,
				anySourceLabelPrefix + k8sConst.PodNamespaceLabel,
			} {
				for _, e := range pl[i].Spec.Egress {
					for _, es := range e.To {
						if es.PodSelector != nil {
							if n, ok := es.PodSelector.MatchLabels[k]; ok && n == defaults.ConnectivityCheckNamespace {
								es.PodSelector.MatchLabels[k] = t.ctx.params.TestNamespace
							}
						}
						if es.NamespaceSelector != nil {
							if n, ok := es.NamespaceSelector.MatchLabels[k]; ok && n == defaults.ConnectivityCheckNamespace {
								es.NamespaceSelector.MatchLabels[k] = t.ctx.params.TestNamespace
							}
						}
					}
				}
				for _, e := range pl[i].Spec.Ingress {
					for _, es := range e.From {
						if es.PodSelector != nil {
							if n, ok := es.PodSelector.MatchLabels[k]; ok && n == defaults.ConnectivityCheckNamespace {
								es.PodSelector.MatchLabels[k] = t.ctx.params.TestNamespace
							}
						}
						if es.NamespaceSelector != nil {
							if n, ok := es.NamespaceSelector.MatchLabels[k]; ok && n == defaults.ConnectivityCheckNamespace {
								es.NamespaceSelector.MatchLabels[k] = t.ctx.params.TestNamespace
							}
						}
					}
				}
			}
		}
	}

	if err := t.addKNPs(pl...); err != nil {
		t.Fatalf("Adding K8S Network Policies to policy context: %s", err)
	}

	// It is implicit that KNP should be enabled.
	t.WithFeatureRequirements(RequireFeatureEnabled(FeatureKNP))

	return t
}

const (
	NoExcludedCIDRs = iota
	ExternalNodeExcludedCIDRs
)

// CiliumEgressGatewayPolicyParams is used to configure how a CiliumEgressGatewayPolicy template should be configured
// before being applied.
type CiliumEgressGatewayPolicyParams struct {
	// ExcludedCIDRs controls how the ExcludedCIDRs property should be configured
	ExcludedCIDRs int
}

// WithCiliumEgressGatewayPolicy takes a string containing a YAML policy
// document and adds the cilium egress gateway polic(y)(ies) to the scope of the
// Test, to be applied when the test starts running. When calling this method,
// note that the egress gateway enabled feature requirement is applied directly
// here.
func (t *Test) WithCiliumEgressGatewayPolicy(policy string, params CiliumEgressGatewayPolicyParams) *Test {
	pl, err := parseCiliumEgressGatewayPolicyYAML(policy)
	if err != nil {
		t.Fatalf("Parsing policy YAML: %s", err)
	}

	for i := range pl {
		// Change the default test namespace as required.
		for _, k := range []string{
			k8sConst.PodNamespaceLabel,
			kubernetesSourcedLabelPrefix + k8sConst.PodNamespaceLabel,
			anySourceLabelPrefix + k8sConst.PodNamespaceLabel,
		} {
			for _, e := range pl[i].Spec.Selectors {
				ps := e.PodSelector
				if n, ok := ps.MatchLabels[k]; ok && n == defaults.ConnectivityCheckNamespace {
					ps.MatchLabels[k] = t.ctx.params.TestNamespace
				}
			}
		}

		// Set the egress gateway node
		egressGatewayNode := t.EgressGatewayNode()
		if egressGatewayNode == "" {
			t.Fatalf("Cannot find egress gateway node")
		}

		pl[i].Spec.EgressGateway.NodeSelector.MatchLabels["kubernetes.io/hostname"] = egressGatewayNode

		// Set the excluded CIDRs
		pl[i].Spec.ExcludedCIDRs = []v2.IPv4CIDR{}

		switch params.ExcludedCIDRs {
		case ExternalNodeExcludedCIDRs:
			for _, nodeWithoutCiliumIP := range t.Context().params.NodesWithoutCiliumIPs {
				if parsedIP := net.ParseIP(nodeWithoutCiliumIP.IP); parsedIP.To4() == nil {
					continue
				}

				cidr := v2.IPv4CIDR(fmt.Sprintf("%s/32", nodeWithoutCiliumIP.IP))
				pl[i].Spec.ExcludedCIDRs = append(pl[i].Spec.ExcludedCIDRs, cidr)
			}
		}
	}

	if err := t.addCEGPs(pl...); err != nil {
		t.Fatalf("Adding CEGPs to cilium egress gateway policy context: %s", err)
	}

	t.WithFeatureRequirements(RequireFeatureEnabled(FeatureEgressGateway))

	return t
}

// WithScenarios adds Scenarios to Test in the given order.
func (t *Test) WithScenarios(sl ...Scenario) *Test {
	// Disallow adding the same Scenario object multiple times.
	for _, s := range sl {
		if _, ok := t.scenarios[s]; ok {
			t.Fatalf("Scenario %v already in %s's list of Scenarios", s, t)
		}

		t.scenarios[s] = make([]*Action, 0)
	}

	return t
}

// WithFeatureRequirements adds FeatureRequirements to Test, all of which
// must be satisfied in order for the test to be run. It adds only features
// that are not already present in the requirements.
func (t *Test) WithFeatureRequirements(reqs ...FeatureRequirement) *Test {
	if len(reqs) == 0 {
		return t
	}

	for _, target := range reqs {
		var seen bool
		for _, r := range t.requirements {
			if target == r {
				// Save the state of the target as seen if already in the requirements list.
				seen = true
			}
		}
		if !seen {
			// Target requirement not present, let's add it.
			t.requirements = append(t.requirements, target)
		}
	}

	return t
}

// WithIPRoutesFromOutsideToPodCIDRs instructs the test runner that
// podCIDR => nodeIP routes needs to be installed on a node which doesn't run
// Cilium before running the test (and removed after the test completion).
func (t *Test) WithIPRoutesFromOutsideToPodCIDRs() *Test {
	if !t.Context().Params().IncludeUnsafeTests {
		t.Fatal("WithIPRoutesFromOutsideToPodCIDRs() requires enabling --include-unsafe-tests")
	}

	t.installIPRoutesFromOutsideToPodCIDRs = true

	return t
}

// WithCiliumVersion adds a requirement for a Cilium vsn in order for the test
// to run.
func (t *Test) WithCiliumVersion(vsn string) *Test {
	t.requiredCiliumVSN = versioncheck.MustCompile(vsn)

	return t
}

// WithSecret takes a Secret and adds it to the cluster during the test
func (t *Test) WithSecret(secret *corev1.Secret) *Test {

	// Change namespace of the secret to the test namespace
	secret.SetNamespace(t.ctx.params.TestNamespace)

	if err := t.addSecrets(secret); err != nil {
		t.Fatalf("Adding secret: %s", err)
	}
	return t
}

// WithCABundleSecret makes the secret `cabundle` with a CA bundle and adds it to the cluster
func (t *Test) WithCABundleSecret() *Test {
	if len(caBundle) == 0 {
		t.Fatalf("CA bundle is empty")
	}

	secret := &corev1.Secret{
		ObjectMeta: metav1.ObjectMeta{
			Name:      "cabundle",
			Namespace: t.ctx.params.TestNamespace,
		},
		Data: map[string][]byte{
			"ca.crt": caBundle,
		},
	}

	if err := t.addSecrets(secret); err != nil {
		t.Fatalf("Adding CA bundle secret: %s", err)
	}
	return t
}

// WithCertificate makes a secret with a certificate and adds it to the cluster
func (t *Test) WithCertificate(name, hostname string) *Test {
	caCert, _, caKey, err := initca.New(&csr.CertificateRequest{
		KeyRequest: csr.NewKeyRequest(),
		CN:         "Cilium Test CA",
	})
	if err != nil {
		t.Fatalf("Unable to create CA: %s", err)
	}

	g := &csr.Generator{Validator: genkey.Validator}
	csrBytes, keyBytes, err := g.ProcessRequest(&csr.CertificateRequest{
		CN:    hostname,
		Hosts: []string{hostname},
	})
	if err != nil {
		t.Fatalf("Unable to create CSR: %s", err)
	}
	parsedCa, err := helpers.ParseCertificatePEM(caCert)
	if err != nil {
		t.Fatalf("Unable to parse CA: %s", err)
	}
	caPriv, err := helpers.ParsePrivateKeyPEM(caKey)
	if err != nil {
		t.Fatalf("Unable to parse CA key: %s", err)
	}

	signConf := &config.Signing{
		Default: &config.SigningProfile{
			Expiry: 365 * 24 * time.Hour,
			Usage:  []string{"key encipherment", "server auth", "digital signature"},
		},
	}

	s, err := local.NewSigner(caPriv, parsedCa, signer.DefaultSigAlgo(caPriv), signConf)
	if err != nil {
		t.Fatalf("Unable to create signer: %s", err)
	}
	certBytes, err := s.Sign(signer.SignRequest{Request: string(csrBytes)})
	if err != nil {
		t.Fatalf("Unable to sign certificate: %s", err)
	}

	if t.certificateCAs == nil {
		t.certificateCAs = make(map[string][]byte)
	}
	t.certificateCAs[name] = caCert

	return t.WithSecret(&corev1.Secret{
		ObjectMeta: metav1.ObjectMeta{
			Name: name,
		},
		Type: corev1.SecretTypeTLS,
		Data: map[string][]byte{
			corev1.TLSCertKey:       certBytes,
			corev1.TLSPrivateKeyKey: keyBytes,
		},
	})
}

// SetupFunc is a callback meant to be called before running the test.
// It performs additional setup needed to run tests.
type SetupFunc func(ctx context.Context, t *Test, testCtx *ConnectivityTest) error

// WithSetupFunc registers a SetupFunc callback to be executed just before
// the test runs.
func (t *Test) WithSetupFunc(f SetupFunc) *Test {
	t.before = append(t.before, f)
	return t
}

// WithFinalizer registers a finalizer to be executed when Run() returns.
func (t *Test) WithFinalizer(f func() error) *Test {
	t.finalizers = append(t.finalizers, f)
	return t
}

// NewAction creates a new Action. s must be the Scenario the Action is created
// for, name should be a visually-distinguishable name, src is the execution
// Pod of the action, and dst is the network target the Action will connect to.
func (t *Test) NewAction(s Scenario, name string, src *Pod, dst TestPeer, ipFam IPFamily) *Action {
	a := newAction(t, name, s, src, dst, ipFam)

	// Obtain the expected result for this particular action by calling
	// the registered expectation function.
	a.expEgress, a.expIngress = t.expectations(a)

	// Store a list of Actions per Scenario.
	t.scenarios[s] = append(t.scenarios[s], a)

	return a
}

// failedActions returns a list of failed Actions in the Test.
func (t *Test) failedActions() []*Action {
	var out []*Action

	for _, s := range t.scenarios {
		for _, a := range s {
			if a.failed {
				out = append(out, a)
			}
		}
	}

	return out
}

func (t *Test) NodesWithoutCilium() []string {
	return t.ctx.NodesWithoutCilium()
}

// EgressGatewayNode returns the name of the node that is supposed to act as
// egress gateway in the egress gateway tests.
//
// Currently the designated node is the one running the other=client client pod.
func (t *Test) EgressGatewayNode() string {
	for _, clientPod := range t.ctx.clientPods {
		if clientPod.Pod.Labels["other"] == "client" {
			return clientPod.Pod.Spec.NodeName
		}
	}

	return ""
}

func (t *Test) collectSysdump() {
	collector, err := sysdump.NewCollector(t.ctx.K8sClient(), t.ctx.params.SysdumpOptions, time.Now(), t.ctx.version)
	if err != nil {
		t.Failf("Failed to create sysdump collector: %v", err)
		return
	}

	if err = collector.Run(); err != nil {
		t.Failf("Failed to collect sysdump: %v", err)
	}
}

func (t *Test) ForEachIPFamily(do func(IPFamily)) {
	ipFams := []IPFamily{IPFamilyV4, IPFamilyV6}

	// The per-endpoint routes feature is broken with IPv6 on < v1.14 when there
	// are any netpols installed (https://github.com/cilium/cilium/issues/23852
	// and https://github.com/cilium/cilium/issues/23910).
	if f, ok := t.Context().Feature(FeatureEndpointRoutes); ok &&
		f.Enabled && (len(t.cnps) > 0 || len(t.knps) > 0) &&
		versioncheck.MustCompile("<1.14.0")(t.Context().CiliumVersion) {

		ipFams = []IPFamily{IPFamilyV4}
	}

	for _, ipFam := range ipFams {
		switch ipFam {
		case IPFamilyV4:
			if f, ok := t.ctx.Features[FeatureIPv4]; ok && f.Enabled {
				do(ipFam)
			}

		case IPFamilyV6:
			if f, ok := t.ctx.Features[FeatureIPv6]; ok && f.Enabled {
				do(ipFam)
			}
		}
	}
}

// CertificateCAs returns the CAs used to sign the certificates within the test.
func (t *Test) CertificateCAs() map[string][]byte {
	return t.certificateCAs
}

func (t *Test) CiliumNetworkPolicies() map[string]*ciliumv2.CiliumNetworkPolicy {
	return t.cnps
}

func (t *Test) KubernetesNetworkPolicies() map[string]*networkingv1.NetworkPolicy {
	return t.knps
}
