package linkerd

import (
	"fmt"
	"reflect"

	"github.com/fluxcd/pkg/ssa"
	"github.com/linkerd/linkerd2/pkg/k8s"
	corev1 "k8s.io/api/core/v1"
	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
	"k8s.io/apimachinery/pkg/labels"
	"k8s.io/apimachinery/pkg/types"
	"sigs.k8s.io/controller-runtime/pkg/client"

	"edge-infra.dev/pkg/edge/constants"
	l5dv1alpha1 "edge-infra.dev/pkg/edge/linkerd/k8s/apis/linkerd/v1alpha1"
)

const (
	// Linkerd namespace
	Namespace string = "linkerd"
	// Linkerd controller name
	LinkerdControllerName string = "linkerdctl"
	// Workloadinjection controller name
	WorkloadInjectionControllerName string = "linkerdctl-workloadinjection"
	// Name of linkerd destination controlplane pods
	Destination string = "linkerd-destination"
	// Name of linkerd proxy injector controlplane pods
	ProxyInjector string = "linkerd-proxy-injector"
	// Name of linkerd identity controlplane pods
	Identity string = "linkerd-identity"
	// Name of linkerd trust anchor
	TrustAnchorName string = "linkerd-trust-anchor"
	// Name of linkerd indentity issuer
	IssuerName string = "linkerd-identity-issuer"
	// Linkerd admin port
	AdminPort string = "linkerd-admin"
	// Common name for linkerd identity
	IdentityCommonName string = "identity.linkerd.cluster.local"
	// Linkerd injection annotation
	InjectionAnnotation string = "linkerd.io/inject"
	// Linkerd proxy version annotation
	ProxyVersionAnnotation string = "linkerd.io/proxy-version"
	// Control plane default replica scale
	DefaultReplicaScale int32 = 1
	// Name of the identity config map
	LinkerdIdentityConfigMap string = "linkerd-identity-trust-roots"
	// Trust anchor certificate lifetime
	CertDurationYear int = 2
)

var (
	ControlPlaneSelector = labels.SelectorFromSet(labels.Set{"linkerd.io/control-plane-ns": Namespace})
	ControllerContainers = []string{"destination", "sp-validator", "identity", "proxy-injector"}
)

const (
	// Linkerd log formatting to json so fluentbit can parse it
	JSONLogFormat string = "json"

	// Log levels, taken from https://linkerd.io/2.11/reference/proxy-log-level/
	// and https://github.com/linkerd/linkerd2/blob/67bcd8f64243e15519b846afe345c4d72b559173/pkg/flags/flags.go#L36
	//
	// NOTE: Only info, debug, error, and warn are supported by the Go components,
	// and only one can be provided at a time. See WithLogLevel for more information

	TraceLogLevel string = "trace"
	InfoLogLevel  string = "info"
	DebugLogLevel string = "debug"
	ErrorLogLevel string = "error"
	WarnLogLevel  string = "warn"

	// linkerd iptables mode
	IptablesModes string = "nft"
)

const (
	// DefaultThinPosIdentityIssuerCertificateDurationHours is the issuer certificate default
	// maximum certificate duration for linkerd under thin topology
	DefaultThinPosIdentityIssuerCertificateDurationHours = uint(40)
	// DefaultThinPosIdentityIssuerCertificateRenewBeforeHours is the issuer certificate default renew before
	// for linkerd under thin topology
	DefaultThinPosIdentityIssuerCertificateRenewBeforeHours = uint(25)
	// DefaultThickPosIdentityIssuerCertificateDurationHours is the issuer certificate default
	// maximum certificate duration for linkerd under thick topology
	DefaultThickPosIdentityIssuerCertificateDurationHours = uint(96)
	// DefaultThickPosIdentityIssuerCertificateRenewBeforeHours is the issuer certificate default renew before
	// for linkerd under thick topology
	DefaultThickPosIdentityIssuerCertificateRenewBeforeHours = uint(72)
)

// Typed namespaced name for trust anchor
func TrustAnchorKey() types.NamespacedName {
	return types.NamespacedName{Name: TrustAnchorName, Namespace: Namespace}
}

// Typed namespaced name for linkerd identity issuer
func IssuerKey() types.NamespacedName {
	return types.NamespacedName{Name: IssuerName, Namespace: Namespace}
}

// OwnerRef creates an owner reference for this controller that should be added
// to objects this controller / Linkerd object owns.  this enables things like
// automated garbage collection
func OwnerRef(l5d *l5dv1alpha1.Linkerd) []metav1.OwnerReference {
	return []metav1.OwnerReference{
		*metav1.NewControllerRef(
			l5d,
			l5dv1alpha1.GroupVersion.WithKind(reflect.TypeOf(l5dv1alpha1.Linkerd{}).Name()),
		),
	}
}

// CreateOpts returns client.CreatOptions marking the linkerd controller as the owner.
// The result string should match what fluxcd/pkg/ssa.Onwer adds to resources.
func CreateOpts() *client.CreateOptions {
	return &client.CreateOptions{FieldManager: fmt.Sprintf("%s/%s", constants.Domain, LinkerdControllerName)}
}

// filters out unchanged objects from changeset
func FilterChanged(changeSet *ssa.ChangeSet) []ssa.ChangeSetEntry {
	changedEntries := []ssa.ChangeSetEntry{}
	for _, entry := range changeSet.Entries {
		if entry.Action != ssa.UnchangedAction {
			changedEntries = append(changedEntries, entry)
		}
	}
	return changedEntries
}

// ProxyContainerStatus returns the container status for the linkerd proxy sidecar
func ProxyContainerStatus(pod *corev1.Pod) *corev1.ContainerStatus {
	for _, status := range append(pod.Status.ContainerStatuses, pod.Status.InitContainerStatuses...) {
		if status.Name == k8s.ProxyContainerName {
			return &status
		}
	}
	return nil
}

// ProxyExists returns true if the pod contains a linkerd proxy sidecar
// either as an init container (for native) or a regular container (for injected)
func ProxyExists(pod *corev1.Pod) bool {
	allContainers := append(pod.Spec.InitContainers, pod.Spec.Containers...)
	for _, container := range allContainers {
		if container.Name == k8s.ProxyContainerName {
			return true
		}
	}
	return false
}