/*
Copyright 2019 The Rook Authors. All rights reserved.

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

	http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/

package csi

import (
	"fmt"
	"os"
	"strconv"
	"strings"
	"time"

	"github.com/pkg/errors"

	"github.com/rook/rook/pkg/operator/k8sutil"
	"github.com/rook/rook/pkg/operator/k8sutil/cmdreporter"

	apps "k8s.io/api/apps/v1"
	corev1 "k8s.io/api/core/v1"
	k8scsi "k8s.io/api/storage/v1beta1"
	apierrors "k8s.io/apimachinery/pkg/api/errors"
	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
	"k8s.io/apimachinery/pkg/version"
	"k8s.io/client-go/kubernetes"
)

type Param struct {
	CSIPluginImage             string
	RegistrarImage             string
	ProvisionerImage           string
	AttacherImage              string
	SnapshotterImage           string
	ResizerImage               string
	DriverNamePrefix           string
	EnableSnapshotter          string
	EnableCSIGRPCMetrics       string
	KubeletDirPath             string
	ForceCephFSKernelClient    string
	CephFSPluginUpdateStrategy string
	RBDPluginUpdateStrategy    string
	LogLevel                   uint8
	CephFSGRPCMetricsPort      uint16
	CephFSLivenessMetricsPort  uint16
	RBDGRPCMetricsPort         uint16
	RBDLivenessMetricsPort     uint16
}

type templateParam struct {
	Param
	// non-global template only parameters
	Namespace string
}

var (
	CSIParam Param

	EnableRBD            = false
	EnableCephFS         = false
	EnableCSIGRPCMetrics = false
	AllowUnsupported     = false

	//driver names
	CephFSDriverName string
	RBDDriverName    string

	// template paths
	RBDPluginTemplatePath         string
	RBDProvisionerSTSTemplatePath string
	RBDProvisionerDepTemplatePath string

	CephFSPluginTemplatePath         string
	CephFSProvisionerSTSTemplatePath string
	CephFSProvisionerDepTemplatePath string

	// configuration map for csi
	ConfigName = "rook-ceph-csi-config"
	ConfigKey  = "csi-cluster-config-json"
)

// Specify default images as var instead of const so that they can be overridden with the Go
// linker's -X flag. This allows users to easily build images with a different opinionated set of
// images without having to specify them manually in charts/manifests which can make upgrades more
// manually challenging.
var (
	// image names
	DefaultCSIPluginImage   = "quay.io/cephcsi/cephcsi:v2.0.0"
	DefaultRegistrarImage   = "quay.io/k8scsi/csi-node-driver-registrar:v1.2.0"
	DefaultProvisionerImage = "quay.io/k8scsi/csi-provisioner:v1.4.0"
	DefaultAttacherImage    = "quay.io/k8scsi/csi-attacher:v2.1.0"
	DefaultSnapshotterImage = "quay.io/k8scsi/csi-snapshotter:v1.2.2"
	defaultResizerImage     = "quay.io/k8scsi/csi-resizer:v0.4.0"
)

const (
	KubeMinMajor                   = "1"
	KubeMinMinor                   = "13"
	provDeploymentSuppVersion      = "14"
	kubeMinVerForFilesystemRestore = "15"
	kubeMinVerForBlockRestore      = "16"

	// toleration and node affinity
	provisionerTolerationsEnv  = "CSI_PROVISIONER_TOLERATIONS"
	provisionerNodeAffinityEnv = "CSI_PROVISIONER_NODE_AFFINITY"
	pluginTolerationsEnv       = "CSI_PLUGIN_TOLERATIONS"
	pluginNodeAffinityEnv      = "CSI_PLUGIN_NODE_AFFINITY"

	// kubelet directory path
	DefaultKubeletDirPath = "/var/lib/kubelet"

	// template
	DefaultRBDPluginTemplatePath         = "/etc/ceph-csi/rbd/csi-rbdplugin.yaml"
	DefaultRBDProvisionerSTSTemplatePath = "/etc/ceph-csi/rbd/csi-rbdplugin-provisioner-sts.yaml"
	DefaultRBDProvisionerDepTemplatePath = "/etc/ceph-csi/rbd/csi-rbdplugin-provisioner-dep.yaml"
	DefaultRBDPluginServiceTemplatePath  = "/etc/ceph-csi/rbd/csi-rbdplugin-svc.yaml"

	DefaultCephFSPluginTemplatePath         = "/etc/ceph-csi/cephfs/csi-cephfsplugin.yaml"
	DefaultCephFSProvisionerSTSTemplatePath = "/etc/ceph-csi/cephfs/csi-cephfsplugin-provisioner-sts.yaml"
	DefaultCephFSProvisionerDepTemplatePath = "/etc/ceph-csi/cephfs/csi-cephfsplugin-provisioner-dep.yaml"
	DefaultCephFSPluginServiceTemplatePath  = "/etc/ceph-csi/cephfs/csi-cephfsplugin-svc.yaml"

	// grpc metrics and liveness port for cephfs  and rbd
	DefaultCephFSGRPCMerticsPort     uint16 = 9091
	DefaultCephFSLivenessMerticsPort uint16 = 9081
	DefaultRBDGRPCMerticsPort        uint16 = 9090
	DefaultRBDLivenessMerticsPort    uint16 = 9080

	detectCSIVersionName   = "rook-ceph-csi-detect-version"
	operatorDeploymentName = "rook-ceph-operator"
	// default log level for csi containers
	defaultLogLevel uint8 = 0
)

func CSIEnabled() bool {
	return EnableRBD || EnableCephFS
}

func ValidateCSIParam() error {

	if len(CSIParam.CSIPluginImage) == 0 {
		return errors.New("missing csi rbd plugin image")
	}
	if len(CSIParam.RegistrarImage) == 0 {
		return errors.New("missing csi registrar image")
	}
	if len(CSIParam.ProvisionerImage) == 0 {
		return errors.New("missing csi provisioner image")
	}
	if len(CSIParam.AttacherImage) == 0 {
		return errors.New("missing csi attacher image")
	}

	if EnableRBD {
		if len(RBDPluginTemplatePath) == 0 {
			return errors.New("missing rbd plugin template path")
		}
		if len(RBDProvisionerSTSTemplatePath) == 0 && len(RBDProvisionerDepTemplatePath) == 0 {
			return errors.New("missing rbd provisioner template path")
		}
	}

	if EnableCephFS {
		if len(CephFSPluginTemplatePath) == 0 {
			return errors.New("missing cephfs plugin template path")
		}
		if len(CephFSProvisionerSTSTemplatePath) == 0 && len(CephFSProvisionerDepTemplatePath) == 0 {
			return errors.New("missing ceph provisioner template path")
		}
	}
	return nil
}

func StartCSIDrivers(namespace string, clientset kubernetes.Interface, ver *version.Info) error {
	var (
		err                                                   error
		rbdPlugin, cephfsPlugin                               *apps.DaemonSet
		rbdProvisionerSTS, cephfsProvisionerSTS               *apps.StatefulSet
		rbdProvisionerDeployment, cephfsProvisionerDeployment *apps.Deployment
		deployProvSTS                                         bool
		rbdService, cephfsService                             *corev1.Service
	)

	ownerRef, err := GetDeploymentOwnerReference(clientset, namespace)
	if err != nil {
		logger.Warningf("could not find deployment owner reference to assign to csi drivers. %v", err)
	}
	if ownerRef != nil {
		blockOwnerDeletion := false
		ownerRef.BlockOwnerDeletion = &blockOwnerDeletion
	}

	// create an empty config map. config map will be filled with data
	// later when clusters have mons
	err = CreateCsiConfigMap(namespace, clientset, ownerRef)
	if err != nil {
		return errors.Wrapf(err, "failed creating csi config map")
	}

	tp := templateParam{
		Param:     CSIParam,
		Namespace: namespace,
	}
	// if the user didn't specify a custom DriverNamePrefix use
	// the namespace (and a dot).
	if tp.DriverNamePrefix == "" {
		tp.DriverNamePrefix = fmt.Sprintf("%s.", namespace)
	}

	CephFSDriverName = tp.DriverNamePrefix + "cephfs.csi.ceph.com"
	RBDDriverName = tp.DriverNamePrefix + "rbd.csi.ceph.com"

	tp.EnableCSIGRPCMetrics = fmt.Sprintf("%t", EnableCSIGRPCMetrics)

	// If not set or set to anything but "false", the kernel client will be enabled
	kClinet := os.Getenv("CSI_FORCE_CEPHFS_KERNEL_CLIENT")
	if strings.EqualFold(kClinet, "false") {
		tp.ForceCephFSKernelClient = "false"
	} else {
		tp.ForceCephFSKernelClient = "true"
	}
	// parse GRPC and Liveness ports
	tp.CephFSGRPCMetricsPort = getPortFromENV("CSI_CEPHFS_GRPC_METRICS_PORT", DefaultCephFSGRPCMerticsPort)
	tp.CephFSLivenessMetricsPort = getPortFromENV("CSI_CEPHFS_LIVENESS_METRICS_PORT", DefaultCephFSLivenessMerticsPort)

	tp.RBDGRPCMetricsPort = getPortFromENV("CSI_RBD_GRPC_METRICS_PORT", DefaultRBDGRPCMerticsPort)
	tp.RBDLivenessMetricsPort = getPortFromENV("CSI_RBD_LIVENESS_METRICS_PORT", DefaultRBDLivenessMerticsPort)

	enableSnap := os.Getenv("CSI_ENABLE_SNAPSHOTTER")
	if !strings.EqualFold(enableSnap, "false") {
		tp.EnableSnapshotter = "true"
	}

	updateStrategy := os.Getenv("CSI_CEPHFS_PLUGIN_UPDATE_STRATEGY")
	if strings.EqualFold(updateStrategy, "ondelete") {
		tp.CephFSPluginUpdateStrategy = "OnDelete"
	} else {
		tp.CephFSPluginUpdateStrategy = "RollingUpdate"
	}

	updateStrategy = os.Getenv("CSI_RBD_PLUGIN_UPDATE_STRATEGY")
	if strings.EqualFold(updateStrategy, "ondelete") {
		tp.RBDPluginUpdateStrategy = "OnDelete"
	} else {
		tp.RBDPluginUpdateStrategy = "RollingUpdate"
	}

	if ver.Major > KubeMinMajor || (ver.Major == KubeMinMajor && ver.Minor < provDeploymentSuppVersion) {
		deployProvSTS = true
	}

	tp.ResizerImage = os.Getenv("ROOK_CSI_RESIZER_IMAGE")
	if tp.ResizerImage == "" {
		tp.ResizerImage = defaultResizerImage
	}

	if ver.Major < KubeMinMajor || ver.Major == KubeMinMajor && ver.Minor < kubeMinVerForFilesystemRestore {
		logger.Warning("CSI Filesystem volume expansion requires Kubernetes version >=1.15.0")
	}
	if ver.Major < KubeMinMajor || ver.Major == KubeMinMajor && ver.Minor < kubeMinVerForBlockRestore {
		logger.Warning("CSI Block volume expansion requires Kubernetes version >=1.16.0")
	}

	logLevel := os.Getenv("CSI_LOG_LEVEL")
	tp.LogLevel = defaultLogLevel
	if logLevel != "" {
		l, err := strconv.ParseUint(logLevel, 10, 8)
		if err != nil {
			logger.Errorf("failed to parse CSI_LOG_LEVEL. Defaulting to %d. %v", defaultLogLevel, err)
		} else {
			tp.LogLevel = uint8(l)
		}
	}

	if EnableRBD {
		rbdPlugin, err = templateToDaemonSet("rbdplugin", RBDPluginTemplatePath, tp)
		if err != nil {
			return errors.Wrapf(err, "failed to load rbdplugin template")
		}
		if deployProvSTS {
			rbdProvisionerSTS, err = templateToStatefulSet("rbd-provisioner", RBDProvisionerSTSTemplatePath, tp)
			if err != nil {
				return errors.Wrapf(err, "failed to load rbd provisioner statefulset template")
			}
		} else {
			rbdProvisionerDeployment, err = templateToDeployment("rbd-provisioner", RBDProvisionerDepTemplatePath, tp)
			if err != nil {
				return errors.Wrapf(err, "failed to load rbd provisioner deployment template")
			}
		}
		rbdService, err = templateToService("rbd-service", DefaultRBDPluginServiceTemplatePath, tp)
		if err != nil {
			return errors.Wrapf(err, "failed to load rbd plugin service template")
		}
	}
	if EnableCephFS {
		cephfsPlugin, err = templateToDaemonSet("cephfsplugin", CephFSPluginTemplatePath, tp)
		if err != nil {
			return errors.Wrapf(err, "failed to load CephFS plugin template")
		}
		if deployProvSTS {
			cephfsProvisionerSTS, err = templateToStatefulSet("cephfs-provisioner", CephFSProvisionerSTSTemplatePath, tp)
			if err != nil {
				return errors.Wrapf(err, "failed to load CephFS provisioner statefulset template")
			}
		} else {
			cephfsProvisionerDeployment, err = templateToDeployment("cephfs-provisioner", CephFSProvisionerDepTemplatePath, tp)
			if err != nil {
				return errors.Wrapf(err, "failed to load rbd provisioner deployment template")
			}
		}
		cephfsService, err = templateToService("cephfs-service", DefaultCephFSPluginServiceTemplatePath, tp)
		if err != nil {
			return errors.Wrapf(err, "failed to load cephfs plugin service template")
		}
	}
	// get provisioner toleration and node affinity
	provisionerTolerations := getToleration(clientset, true)
	provisionerNodeAffinity := getNodeAffinity(clientset, true)
	// get plugin toleration and node affinity
	pluginTolerations := getToleration(clientset, false)
	pluginNodeAffinity := getNodeAffinity(clientset, false)
	if rbdPlugin != nil {
		applyToPodSpec(&rbdPlugin.Spec.Template.Spec, pluginNodeAffinity, pluginTolerations)
		k8sutil.SetOwnerRef(&rbdPlugin.ObjectMeta, ownerRef)
		err = k8sutil.CreateDaemonSet("csi-rbdplugin", namespace, clientset, rbdPlugin)
		if err != nil {
			return errors.Wrapf(err, "failed to start rbdplugin daemonset: %+v", rbdPlugin)
		}
		k8sutil.AddRookVersionLabelToDaemonSet(rbdPlugin)
	}

	if rbdProvisionerSTS != nil {
		applyToPodSpec(&rbdProvisionerSTS.Spec.Template.Spec, provisionerNodeAffinity, provisionerTolerations)
		k8sutil.SetOwnerRef(&rbdProvisionerSTS.ObjectMeta, ownerRef)
		err = k8sutil.CreateStatefulSet("csi-rbdplugin-provisioner", namespace, clientset, rbdProvisionerSTS)
		if err != nil {
			return errors.Wrapf(err, "failed to start rbd provisioner statefulset: %+v", rbdProvisionerSTS)
		}
		k8sutil.AddRookVersionLabelToStatefulSet(rbdProvisionerSTS)
	} else if rbdProvisionerDeployment != nil {
		applyToPodSpec(&rbdProvisionerDeployment.Spec.Template.Spec, provisionerNodeAffinity, provisionerTolerations)
		k8sutil.SetOwnerRef(&rbdProvisionerDeployment.ObjectMeta, ownerRef)
		err = k8sutil.CreateDeployment("csi-rbdplugin-provisioner", namespace, clientset, rbdProvisionerDeployment)
		if err != nil {
			return errors.Wrapf(err, "failed to start rbd provisioner deployment: %+v", rbdProvisionerDeployment)
		}
		k8sutil.AddRookVersionLabelToDeployment(rbdProvisionerDeployment)
	}

	if rbdService != nil {
		k8sutil.SetOwnerRef(&rbdService.ObjectMeta, ownerRef)
		_, err = k8sutil.CreateOrUpdateService(clientset, namespace, rbdService)
		if err != nil {
			return errors.Wrapf(err, "failed to create rbd service: %+v", rbdService)
		}
	}

	if cephfsPlugin != nil {
		applyToPodSpec(&cephfsPlugin.Spec.Template.Spec, pluginNodeAffinity, pluginTolerations)
		k8sutil.SetOwnerRef(&cephfsPlugin.ObjectMeta, ownerRef)
		err = k8sutil.CreateDaemonSet("csi-cephfsplugin", namespace, clientset, cephfsPlugin)
		if err != nil {
			return errors.Wrapf(err, "failed to start cephfs plugin daemonset: %+v", cephfsPlugin)
		}
		k8sutil.AddRookVersionLabelToDaemonSet(cephfsPlugin)
	}

	if cephfsProvisionerSTS != nil {
		applyToPodSpec(&cephfsProvisionerSTS.Spec.Template.Spec, provisionerNodeAffinity, provisionerTolerations)
		k8sutil.SetOwnerRef(&cephfsProvisionerSTS.ObjectMeta, ownerRef)
		err = k8sutil.CreateStatefulSet("csi-cephfsplugin-provisioner", namespace, clientset, cephfsProvisionerSTS)
		if err != nil {
			return errors.Wrapf(err, "failed to start cephfs provisioner statefulset: %+v", cephfsProvisionerSTS)
		}
		k8sutil.AddRookVersionLabelToStatefulSet(cephfsProvisionerSTS)

	} else if cephfsProvisionerDeployment != nil {
		applyToPodSpec(&cephfsProvisionerDeployment.Spec.Template.Spec, provisionerNodeAffinity, provisionerTolerations)
		k8sutil.SetOwnerRef(&cephfsProvisionerDeployment.ObjectMeta, ownerRef)
		err = k8sutil.CreateDeployment("csi-cephfsplugin-provisioner", namespace, clientset, cephfsProvisionerDeployment)
		if err != nil {
			return errors.Wrapf(err, "failed to start cephfs provisioner deployment: %+v", cephfsProvisionerDeployment)
		}
		k8sutil.AddRookVersionLabelToDeployment(cephfsProvisionerDeployment)
	}
	if cephfsService != nil {
		k8sutil.SetOwnerRef(&cephfsService.ObjectMeta, ownerRef)
		_, err = k8sutil.CreateOrUpdateService(clientset, namespace, cephfsService)
		if err != nil {
			return errors.Wrapf(err, "failed to create rbd service: %+v", cephfsService)
		}
	}

	if ver.Major > KubeMinMajor || (ver.Major == KubeMinMajor && ver.Minor >= provDeploymentSuppVersion) {
		err = createCSIDriverInfo(clientset, RBDDriverName, ownerRef)
		if err != nil {
			return errors.Wrapf(err, "failed to create CSI driver object for %q", RBDDriverName)
		}
		err = createCSIDriverInfo(clientset, CephFSDriverName, ownerRef)
		if err != nil {
			return errors.Wrapf(err, "failed to create CSI driver object for %q", CephFSDriverName)
		}
	}
	return nil
}

func StopCSIDrivers(namespace string, clientset kubernetes.Interface) error {
	logger.Warningf("Skipped removing the CSI driver")

	// FIX: Restore the ownerRefs for all CSI resources in order to delegate entirely to the ConfigMap deletion.
	return DeleteCsiConfigMap(namespace, clientset)
}

// createCSIDriverInfo Registers CSI driver by creating a CSIDriver object
func createCSIDriverInfo(clientset kubernetes.Interface, name string, ownerRef *metav1.OwnerReference) error {
	attach := true
	mountInfo := false
	// Create CSIDriver object
	csiDriver := &k8scsi.CSIDriver{
		ObjectMeta: metav1.ObjectMeta{
			Name: name,
		},
		Spec: k8scsi.CSIDriverSpec{
			AttachRequired: &attach,
			PodInfoOnMount: &mountInfo,
		},
	}
	csidrivers := clientset.StorageV1beta1().CSIDrivers()
	k8sutil.SetOwnerRef(&csiDriver.ObjectMeta, ownerRef)
	_, err := csidrivers.Create(csiDriver)
	if err == nil {
		logger.Infof("CSIDriver object created for driver %q", name)
		return nil
	}
	if apierrors.IsAlreadyExists(err) {
		logger.Infof("CSIDriver CRD already had been registered for %q", name)
		return nil
	}

	return err
}

// GetDeploymentOwnerReference returns an OwnerReference to the rook-ceph-operator deployment
func GetDeploymentOwnerReference(clientset kubernetes.Interface, namespace string) (*metav1.OwnerReference, error) {
	var deploymentRef *metav1.OwnerReference
	podName := os.Getenv(k8sutil.PodNameEnvVar)
	pod, err := clientset.CoreV1().Pods(namespace).Get(podName, metav1.GetOptions{})
	if err != nil {
		return nil, errors.Wrapf(err, "could not find pod %q to find deployment owner reference", podName)
	}
	for _, podOwner := range pod.OwnerReferences {
		if podOwner.Kind == "ReplicaSet" {
			replicaset, err := clientset.AppsV1().ReplicaSets(namespace).Get(podOwner.Name, metav1.GetOptions{})
			if err != nil {
				return nil, errors.Wrapf(err, "could not find replicaset %q to find deployment owner reference", podOwner.Name)
			}
			for _, replicasetOwner := range replicaset.OwnerReferences {
				if replicasetOwner.Kind == "Deployment" {
					deploymentRef = &replicasetOwner
				}
			}
		}
	}
	if deploymentRef == nil {
		return nil, errors.New("could not find owner reference for rook-ceph deployment")
	}
	return deploymentRef, nil
}

// ValidateCSIVersion checks if the configured ceph-csi image is supported
func ValidateCSIVersion(clientset kubernetes.Interface, namespace, rookImage, serviceAccountName string) error {
	timeout := 15 * time.Minute

	logger.Infof("detecting the ceph csi image version for image %q", CSIParam.CSIPluginImage)

	pod, err := k8sutil.GetRunningPod(clientset)
	if err != nil {
		return errors.Wrap(err, "could not get the rook operator pod to obtain the owner reference")
	}
	if pod == nil || len(pod.GetOwnerReferences()) == 0 {
		return errors.New("empty owner reference in rook operator pod")
	}
	ownerRef := pod.GetOwnerReferences()[0].DeepCopy()

	*ownerRef.BlockOwnerDeletion = false

	versionReporter, err := cmdreporter.New(
		clientset,
		ownerRef,
		detectCSIVersionName, detectCSIVersionName, namespace,
		[]string{"cephcsi"}, []string{"--version"},
		rookImage, CSIParam.CSIPluginImage)

	if err != nil {
		return errors.Wrap(err, "failed to set up ceph CSI version job")
	}

	job := versionReporter.Job()
	job.Spec.Template.Spec.ServiceAccountName = serviceAccountName

	stdout, _, retcode, err := versionReporter.Run(timeout)
	if err != nil {
		return errors.Wrap(err, "failed to complete ceph CSI version job")
	}

	if retcode != 0 {
		return errors.Errorf("ceph CSI version job returned %d", retcode)
	}

	version, err := extractCephCSIVersion(stdout)
	if err != nil {
		return errors.Wrap(err, "failed to extract ceph CSI version")
	}
	logger.Infof("Detected ceph CSI image version: %q", version)

	if !version.Supported() {
		return errors.Errorf("ceph CSI image needs to be at least version %q", minimum.String())
	}
	return nil
}