/*
Copyright 2016 Skippbox, Ltd 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 transformer

import (
	"encoding/json"
	"fmt"
	"github.com/Sirupsen/logrus"
	"github.com/ghodss/yaml"
	"github.com/skippbox/kompose/pkg/kobject"
	"k8s.io/kubernetes/pkg/api/unversioned"
	"k8s.io/kubernetes/pkg/apis/extensions"
	"k8s.io/kubernetes/pkg/util/intstr"
	"math/rand"
	"os"
	"strconv"
	"strings"

	deployapi "github.com/openshift/origin/pkg/deploy/api"
	"io/ioutil"
	"k8s.io/kubernetes/pkg/api"
	"k8s.io/kubernetes/pkg/runtime"
)

const letterBytes = "abcdefghijklmnopqrstuvwxyz0123456789"

// RandStringBytes generates randomly n-character string
func RandStringBytes(n int) string {
	b := make([]byte, n)
	for i := range b {
		b[i] = letterBytes[rand.Intn(len(letterBytes))]
	}
	return string(b)
}

// Create the file to write to if --out is specified
func createOutFile(out string) *os.File {
	var f *os.File
	var err error
	if len(out) != 0 {
		f, err = os.Create(out)
		if err != nil {
			logrus.Fatalf("error opening file: %v", err)
		}
	}
	return f
}

// Init RC object
func initRC(name string, service kobject.ServiceConfig, replicas int) *api.ReplicationController {
	rc := &api.ReplicationController{
		TypeMeta: unversioned.TypeMeta{
			Kind:       "ReplicationController",
			APIVersion: "v1",
		},
		ObjectMeta: api.ObjectMeta{
			Name: name,
			//Labels: map[string]string{"service": name},
		},
		Spec: api.ReplicationControllerSpec{
			Selector: map[string]string{"service": name},
			Replicas: int32(replicas),
			Template: &api.PodTemplateSpec{
				ObjectMeta: api.ObjectMeta{
				//Labels: map[string]string{"service": name},
				},
				Spec: api.PodSpec{
					Containers: []api.Container{
						{
							Name:  name,
							Image: service.Image,
						},
					},
				},
			},
		},
	}
	return rc
}

// Init SC object
func initSC(name string, service kobject.ServiceConfig) *api.Service {
	sc := &api.Service{
		TypeMeta: unversioned.TypeMeta{
			Kind:       "Service",
			APIVersion: "v1",
		},
		ObjectMeta: api.ObjectMeta{
			Name: name,
			//Labels: map[string]string{"service": name},
		},
		Spec: api.ServiceSpec{
			Selector: map[string]string{"service": name},
		},
	}
	return sc
}

// Init DC object
func initDC(name string, service kobject.ServiceConfig, replicas int) *extensions.Deployment {
	dc := &extensions.Deployment{
		TypeMeta: unversioned.TypeMeta{
			Kind:       "Deployment",
			APIVersion: "extensions/v1beta1",
		},
		ObjectMeta: api.ObjectMeta{
			Name:   name,
			Labels: map[string]string{"service": name},
		},
		Spec: extensions.DeploymentSpec{
			Replicas: int32(replicas),
			Selector: &unversioned.LabelSelector{
				MatchLabels: map[string]string{"service": name},
			},
			//UniqueLabelKey: p.Name,
			Template: api.PodTemplateSpec{
				ObjectMeta: api.ObjectMeta{
					Labels: map[string]string{"service": name},
				},
				Spec: api.PodSpec{
					Containers: []api.Container{
						{
							Name:  name,
							Image: service.Image,
						},
					},
				},
			},
		},
	}
	return dc
}

// Init DS object
func initDS(name string, service kobject.ServiceConfig) *extensions.DaemonSet {
	ds := &extensions.DaemonSet{
		TypeMeta: unversioned.TypeMeta{
			Kind:       "DaemonSet",
			APIVersion: "extensions/v1beta1",
		},
		ObjectMeta: api.ObjectMeta{
			Name: name,
		},
		Spec: extensions.DaemonSetSpec{
			Template: api.PodTemplateSpec{
				ObjectMeta: api.ObjectMeta{
					Name: name,
				},
				Spec: api.PodSpec{
					Containers: []api.Container{
						{
							Name:  name,
							Image: service.Image,
						},
					},
				},
			},
		},
	}
	return ds
}

// initDeploymentConfig initialize OpenShifts DeploymentConfig object
func initDeploymentConfig(name string, service kobject.ServiceConfig, replicas int) *deployapi.DeploymentConfig {
	dc := &deployapi.DeploymentConfig{
		TypeMeta: unversioned.TypeMeta{
			Kind:       "DeploymentConfig",
			APIVersion: "v1",
		},
		ObjectMeta: api.ObjectMeta{
			Name:   name,
			Labels: map[string]string{"service": name},
		},
		Spec: deployapi.DeploymentConfigSpec{
			Replicas: int32(replicas),
			Selector: map[string]string{"service": name},
			//UniqueLabelKey: p.Name,
			Template: &api.PodTemplateSpec{
				ObjectMeta: api.ObjectMeta{
					Labels: map[string]string{"service": name},
				},
				Spec: api.PodSpec{
					Containers: []api.Container{
						{
							Name:  name,
							Image: service.Image,
						},
					},
				},
			},
		},
	}
	return dc
}

// Configure the environment variables.
func configEnvs(name string, service kobject.ServiceConfig) []api.EnvVar {
	envs := []api.EnvVar{}
	for _, v := range service.Environment {
		envs = append(envs, api.EnvVar{
			Name:  v.Name,
			Value: v.Value,
		})
	}

	return envs
}

// Configure the container volumes.
func configVolumes(service kobject.ServiceConfig) ([]api.VolumeMount, []api.Volume) {
	volumesMount := []api.VolumeMount{}
	volumes := []api.Volume{}
	volumeSource := api.VolumeSource{}
	for _, volume := range service.Volumes {
		name, host, container, mode, err := parseVolume(volume)
		if err != nil {
			logrus.Warningf("Failed to configure container volume: %v", err)
			continue
		}

		// if volume name isn't specified, set it to a random string of 20 chars
		if len(name) == 0 {
			name = RandStringBytes(20)
		}
		// check if ro/rw mode is defined, default rw
		readonly := len(mode) > 0 && mode == "ro"

		volumesMount = append(volumesMount, api.VolumeMount{Name: name, ReadOnly: readonly, MountPath: container})

		if len(host) > 0 {
			volumeSource = api.VolumeSource{HostPath: &api.HostPathVolumeSource{Path: host}}
		} else {
			volumeSource = api.VolumeSource{EmptyDir: &api.EmptyDirVolumeSource{}}
		}

		volumes = append(volumes, api.Volume{Name: name, VolumeSource: volumeSource})
	}
	return volumesMount, volumes
}

// parseVolume parse a given volume, which might be [name:][host:]container[:access_mode]
func parseVolume(volume string) (name, host, container, mode string, err error) {
	separator := ":"
	volumeStrings := strings.Split(volume, separator)
	if len(volumeStrings) == 0 {
		return
	}
	// Set name if existed
	if !isPath(volumeStrings[0]) {
		name = volumeStrings[0]
		volumeStrings = volumeStrings[1:]
	}
	if len(volumeStrings) == 0 {
		err = fmt.Errorf("invalid volume format: %s", volume)
		return
	}
	if volumeStrings[len(volumeStrings)-1] == "rw" || volumeStrings[len(volumeStrings)-1] == "ro" {
		mode = volumeStrings[len(volumeStrings)-1]
		volumeStrings = volumeStrings[:len(volumeStrings)-1]
	}
	container = volumeStrings[len(volumeStrings)-1]
	volumeStrings = volumeStrings[:len(volumeStrings)-1]
	if len(volumeStrings) == 1 {
		host = volumeStrings[0]
	}
	if !isPath(container) || (len(host) > 0 && !isPath(host)) || len(volumeStrings) > 1 {
		err = fmt.Errorf("invalid volume format: %s", volume)
		return
	}
	return
}

func isPath(substring string) bool {
	return strings.Contains(substring, "/")
}

// Configure the container ports.
func configPorts(name string, service kobject.ServiceConfig) []api.ContainerPort {
	ports := []api.ContainerPort{}
	for _, port := range service.Port {
		var p api.Protocol
		switch port.Protocol {
		default:
			p = api.ProtocolTCP
		case kobject.ProtocolTCP:
			p = api.ProtocolTCP
		case kobject.ProtocolUDP:
			p = api.ProtocolUDP
		}
		ports = append(ports, api.ContainerPort{
			ContainerPort: port.ContainerPort,
			Protocol:      p,
		})
	}

	return ports
}

// Configure the container service ports.
func configServicePorts(name string, service kobject.ServiceConfig) []api.ServicePort {
	servicePorts := []api.ServicePort{}
	for _, port := range service.Port {
		if port.HostPort == 0 {
			port.HostPort = port.ContainerPort
		}
		var p api.Protocol
		switch port.Protocol {
		default:
			p = api.ProtocolTCP
		case kobject.ProtocolTCP:
			p = api.ProtocolTCP
		case kobject.ProtocolUDP:
			p = api.ProtocolUDP
		}
		var targetPort intstr.IntOrString
		targetPort.IntVal = port.ContainerPort
		targetPort.StrVal = strconv.Itoa(int(port.ContainerPort))
		servicePorts = append(servicePorts, api.ServicePort{
			Name:       strconv.Itoa(int(port.HostPort)),
			Protocol:   p,
			Port:       port.HostPort,
			TargetPort: targetPort,
		})
	}
	return servicePorts
}

// Transform data to json/yaml
func transformer(obj runtime.Object, GenerateYaml bool) ([]byte, error) {
	//  Convert to versioned object
	objectVersion := obj.GetObjectKind().GroupVersionKind()
	version := unversioned.GroupVersion{Group: objectVersion.Group, Version: objectVersion.Version}
	versionedObj, err := api.Scheme.ConvertToVersion(obj, version)
	if err != nil {
		return nil, err
	}

	// convert data to json / yaml
	data, err := json.MarshalIndent(versionedObj, "", "  ")
	if GenerateYaml == true {
		data, err = yaml.Marshal(versionedObj)
	}
	if err != nil {
		return nil, err
	}
	logrus.Debugf("%s\n", data)
	return data, nil
}

func Transform(komposeObject *kobject.KomposeObject, opt kobject.ConvertOptions) (map[string][]byte, map[string][]byte, map[string][]byte, map[string][]byte, map[string][]byte, []string) {
	mServices := make(map[string][]byte)
	mReplicationControllers := make(map[string][]byte)
	mDeployments := make(map[string][]byte)
	mDaemonSets := make(map[string][]byte)

	// OpenShift DeploymentConfigs
	mDeploymentConfigs := make(map[string][]byte)

	f := createOutFile(opt.OutFile)
	defer f.Close()

	var svcnames []string

	for name, service := range komposeObject.ServiceConfigs {
		svcnames = append(svcnames, name)

		rc := initRC(name, service, opt.Replicas)
		sc := initSC(name, service)
		dc := initDC(name, service, opt.Replicas)
		ds := initDS(name, service)
		osDC := initDeploymentConfig(name, service, opt.Replicas) // OpenShift DeploymentConfigs

		// Configure the environment variables.
		envs := configEnvs(name, service)

		// Configure the container command.
		var cmds []string
		for _, cmd := range service.Command {
			cmds = append(cmds, cmd)
		}
		// Configure the container volumes.
		volumesMount, volumes := configVolumes(service)

		// Configure the container ports.
		ports := configPorts(name, service)

		// Configure the service ports.
		servicePorts := configServicePorts(name, service)
		sc.Spec.Ports = servicePorts

		// Configure label
		labels := map[string]string{"service": name}
		sc.ObjectMeta.Labels = labels
		// Configure annotations
		annotations := map[string]string{}
		for key, value := range service.Annotations {
			annotations[key] = value
		}
		sc.ObjectMeta.Annotations = annotations

		// fillTemplate fills the pod template with the value calculated from config
		fillTemplate := func(template *api.PodTemplateSpec) {
			template.Spec.Containers[0].Env = envs
			template.Spec.Containers[0].Command = cmds
			template.Spec.Containers[0].WorkingDir = service.WorkingDir
			template.Spec.Containers[0].VolumeMounts = volumesMount
			template.Spec.Volumes = volumes
			// Configure the container privileged mode
			if service.Privileged == true {
				template.Spec.Containers[0].SecurityContext = &api.SecurityContext{
					Privileged: &service.Privileged,
				}
			}
			template.Spec.Containers[0].Ports = ports
			template.ObjectMeta.Labels = labels
			// Configure the container restart policy.
			switch service.Restart {
			case "", "always":
				template.Spec.RestartPolicy = api.RestartPolicyAlways
			case "no":
				template.Spec.RestartPolicy = api.RestartPolicyNever
			case "on-failure":
				template.Spec.RestartPolicy = api.RestartPolicyOnFailure
			default:
				logrus.Fatalf("Unknown restart policy %s for service %s", service.Restart, name)
			}
		}

		// fillObjectMeta fills the metadata with the value calculated from config
		fillObjectMeta := func(meta *api.ObjectMeta) {
			meta.Labels = labels
			meta.Annotations = annotations
		}

		// Update each supported controllers
		updateController(rc, fillTemplate, fillObjectMeta)
		updateController(dc, fillTemplate, fillObjectMeta)
		updateController(ds, fillTemplate, fillObjectMeta)
		// OpenShift DeploymentConfigs
		updateController(osDC, fillTemplate, fillObjectMeta)

		// convert datarc to json / yaml
		datarc, err := transformer(rc, opt.GenerateYaml)
		if err != nil {
			logrus.Fatalf(err.Error())
		}

		// convert datadc to json / yaml
		datadc, err := transformer(dc, opt.GenerateYaml)
		if err != nil {
			logrus.Fatalf(err.Error())
		}

		// convert datads to json / yaml
		datads, err := transformer(ds, opt.GenerateYaml)
		if err != nil {
			logrus.Fatalf(err.Error())
		}

		var datasvc []byte
		// If ports not provided in configuration we will not make service
		if len(ports) == 0 {
			logrus.Warningf("[%s] Service cannot be created because of missing port.", name)
		} else if len(ports) != 0 {
			// convert datasvc to json / yaml
			datasvc, err = transformer(sc, opt.GenerateYaml)
			if err != nil {
				logrus.Fatalf(err.Error())
			}
		}

		// convert OpenShift DeploymentConfig to json / yaml
		dataDeploymentConfig, err := transformer(osDC, opt.GenerateYaml)
		if err != nil {
			logrus.Fatalf(err.Error())
		}

		mServices[name] = datasvc
		mReplicationControllers[name] = datarc
		mDeployments[name] = datadc
		mDaemonSets[name] = datads
		mDeploymentConfigs[name] = dataDeploymentConfig
	}

	return mServices, mDeployments, mDaemonSets, mReplicationControllers, mDeploymentConfigs, svcnames
}

func PrintControllers(mServices, mDeployments, mDaemonSets, mReplicationControllers, mDeploymentConfigs map[string][]byte, svcnames []string, opt kobject.ConvertOptions, f *os.File) {
	for k, v := range mServices {
		if v != nil {
			print(k, "svc", v, opt.ToStdout, opt.GenerateYaml, f)
		}
	}

	// If --out or --stdout is set, the validation should already prevent multiple controllers being generated
	if opt.CreateD {
		for k, v := range mDeployments {
			print(k, "deployment", v, opt.ToStdout, opt.GenerateYaml, f)
		}
	}

	if opt.CreateDS {
		for k, v := range mDaemonSets {
			print(k, "daemonset", v, opt.ToStdout, opt.GenerateYaml, f)
		}
	}

	if opt.CreateRC {
		for k, v := range mReplicationControllers {
			print(k, "rc", v, opt.ToStdout, opt.GenerateYaml, f)
		}
	}

	if f != nil {
		fmt.Fprintf(os.Stdout, "file %q created\n", opt.OutFile)
	}

	if opt.CreateChart {
		err := generateHelm(opt.InputFile, svcnames, opt.GenerateYaml, opt.CreateD, opt.CreateDS, opt.CreateRC, opt.OutFile)
		if err != nil {
			logrus.Fatalf("Failed to create Chart data: %v", err)
		}
	}

	if opt.CreateDeploymentConfig {
		for k, v := range mDeploymentConfigs {
			print(k, "deploymentconfig", v, opt.ToStdout, opt.GenerateYaml, f)
		}
	}
}

// updateController updates the given object with the given pod template update function and ObjectMeta update function
func updateController(obj runtime.Object, updateTemplate func(*api.PodTemplateSpec), updateMeta func(meta *api.ObjectMeta)) {
	switch t := obj.(type) {
	case *api.ReplicationController:
		if t.Spec.Template == nil {
			t.Spec.Template = &api.PodTemplateSpec{}
		}
		updateTemplate(t.Spec.Template)
		updateMeta(&t.ObjectMeta)
	case *extensions.Deployment:
		updateTemplate(&t.Spec.Template)
		updateMeta(&t.ObjectMeta)
	case *extensions.ReplicaSet:
		updateTemplate(&t.Spec.Template)
		updateMeta(&t.ObjectMeta)
	case *extensions.DaemonSet:
		updateTemplate(&t.Spec.Template)
		updateMeta(&t.ObjectMeta)
	case *deployapi.DeploymentConfig:
		updateTemplate(t.Spec.Template)
		updateMeta(&t.ObjectMeta)
	}
}

func print(name, trailing string, data []byte, toStdout, generateYaml bool, f *os.File) {
	file := fmt.Sprintf("%s-%s.json", name, trailing)
	if generateYaml {
		file = fmt.Sprintf("%s-%s.yaml", name, trailing)
	}
	separator := ""
	if generateYaml {
		separator = "---"
	}
	if toStdout {
		fmt.Fprintf(os.Stdout, "%s%s\n", string(data), separator)
	} else if f != nil {
		// Write all content to a single file f
		if _, err := f.WriteString(fmt.Sprintf("%s%s\n", string(data), separator)); err != nil {
			logrus.Fatalf("Failed to write %s to file: %v", trailing, err)
		}
		f.Sync()
	} else {
		// Write content separately to each file
		if err := ioutil.WriteFile(file, []byte(data), 0644); err != nil {
			logrus.Fatalf("Failed to write %s: %v", trailing, err)
		}
		fmt.Fprintf(os.Stdout, "file %q created\n", file)
	}
}