/*
Copyright 2017 The Kubernetes 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 compose

import (
	"strconv"
	"strings"
	"time"

	libcomposeyaml "github.com/docker/libcompose/yaml"

	"k8s.io/kubernetes/pkg/api"

	"github.com/docker/cli/cli/compose/loader"
	"github.com/docker/cli/cli/compose/types"

	"os"

	"fmt"

	"github.com/kubernetes/kompose/pkg/kobject"
	"github.com/pkg/errors"
	log "github.com/sirupsen/logrus"
)

// converts os.Environ() ([]string) to map[string]string
// based on https://github.com/docker/cli/blob/5dd30732a23bbf14db1c64d084ae4a375f592cfa/cli/command/stack/deploy_composefile.go#L143
func buildEnvironment() (map[string]string, error) {
	env := os.Environ()
	result := make(map[string]string, len(env))
	for _, s := range env {
		// if value is empty, s is like "K=", not "K".
		if !strings.Contains(s, "=") {
			return result, errors.Errorf("unexpected environment %q", s)
		}
		kv := strings.SplitN(s, "=", 2)
		result[kv[0]] = kv[1]
	}
	return result, nil
}

// The purpose of this is not to deploy, but to be able to parse
// v3 of Docker Compose into a suitable format. In this case, whatever is returned
// by docker/cli's ServiceConfig
func parseV3(files []string) (kobject.KomposeObject, error) {

	// In order to get V3 parsing to work, we have to go through some preliminary steps
	// for us to hack up github.com/docker/cli in order to correctly convert to a kobject.KomposeObject

	// Gather the working directory
	workingDir, err := getComposeFileDir(files)
	if err != nil {
		return kobject.KomposeObject{}, err
	}

	// get environment variables
	env, err := buildEnvironment()
	if err != nil {
		return kobject.KomposeObject{}, errors.Wrap(err, "cannot build environment variables")
	}

	var config *types.Config
	for _, file := range files {
		// Load and then parse the YAML first!
		loadedFile, err := ReadFile(file)
		if err != nil {
			return kobject.KomposeObject{}, err
		}

		// Parse the Compose File
		parsedComposeFile, err := loader.ParseYAML(loadedFile)
		if err != nil {
			return kobject.KomposeObject{}, err
		}

		// Config file
		configFile := types.ConfigFile{
			Filename: file,
			Config:   parsedComposeFile,
		}

		// Config details
		configDetails := types.ConfigDetails{
			WorkingDir:  workingDir,
			ConfigFiles: []types.ConfigFile{configFile},
			Environment: env,
		}

		// Actual config
		// We load it in order to retrieve the parsed output configuration!
		// This will output a github.com/docker/cli ServiceConfig
		// Which is similar to our version of ServiceConfig
		currentConfig, err := loader.Load(configDetails)
		if err != nil {
			return kobject.KomposeObject{}, err
		}
		if config == nil {
			config = currentConfig
		} else {
			config, err = mergeComposeObject(config, currentConfig)
			if err != nil {
				return kobject.KomposeObject{}, err
			}
		}
	}

	noSupKeys := checkUnsupportedKeyForV3(config)
	for _, keyName := range noSupKeys {
		log.Warningf("Unsupported %s key - ignoring", keyName)
	}

	// Finally, we convert the object from docker/cli's ServiceConfig to our appropriate one
	komposeObject, err := dockerComposeToKomposeMapping(config)
	if err != nil {
		return kobject.KomposeObject{}, err
	}

	return komposeObject, nil
}

func loadV3Placement(constraints []string) map[string]string {
	placement := make(map[string]string)
	errMsg := " constraints in placement is not supported, only 'node.hostname', 'engine.labels.operatingsystem' and 'node.labels.xxx' (ex: node.labels.something == anything) is supported as a constraint "
	for _, j := range constraints {
		p := strings.Split(j, " == ")
		if len(p) < 2 {
			log.Warn(p[0], errMsg)
			continue
		}
		if p[0] == "node.hostname" {
			placement["kubernetes.io/hostname"] = p[1]
		} else if p[0] == "engine.labels.operatingsystem" {
			placement["beta.kubernetes.io/os"] = p[1]
		} else if strings.HasPrefix(p[0], "node.labels.") {
			label := strings.TrimPrefix(p[0], "node.labels.")
			placement[label] = p[1]
		} else {
			log.Warn(p[0], errMsg)
		}
	}
	return placement
}

// Convert the Docker Compose v3 volumes to []string (the old way)
// TODO: Check to see if it's a "bind" or "volume". Ignore for now.
// TODO: Refactor it similar to loadV3Ports
// See: https://docs.docker.com/compose/compose-file/#long-syntax-3
func loadV3Volumes(volumes []types.ServiceVolumeConfig) []string {
	var volArray []string
	for _, vol := range volumes {

		// There will *always* be Source when parsing
		v := normalizeVolumes(vol.Source)

		if vol.Target != "" {
			v = v + ":" + vol.Target
		}

		if vol.ReadOnly {
			v = v + ":ro"
		}

		volArray = append(volArray, v)
	}
	return volArray
}

// Convert Docker Compose v3 ports to kobject.Ports
func loadV3Ports(ports []types.ServicePortConfig) []kobject.Ports {
	komposePorts := []kobject.Ports{}

	for _, port := range ports {

		// Convert to a kobject struct with ports
		// NOTE: V3 doesn't use IP (they utilize Swarm instead for host-networking).
		// Thus, IP is blank.
		komposePorts = append(komposePorts, kobject.Ports{
			HostPort:      int32(port.Published),
			ContainerPort: int32(port.Target),
			HostIP:        "",
			Protocol:      api.Protocol(strings.ToUpper(string(port.Protocol))),
		})

	}

	return komposePorts
}

/* Convert the HealthCheckConfig as designed by Docker to
a Kubernetes-compatible format.
*/
func parseHealthCheck(composeHealthCheck types.HealthCheckConfig) (kobject.HealthCheck, error) {

	var timeout, interval, retries, startPeriod int32

	// Here we convert the timeout from 1h30s (example) to 36030 seconds.
	if composeHealthCheck.Timeout != nil {
		parse, err := time.ParseDuration(composeHealthCheck.Timeout.String())
		if err != nil {
			return kobject.HealthCheck{}, errors.Wrap(err, "unable to parse health check timeout variable")
		}
		timeout = int32(parse.Seconds())
	}

	if composeHealthCheck.Interval != nil {
		parse, err := time.ParseDuration(composeHealthCheck.Interval.String())
		if err != nil {
			return kobject.HealthCheck{}, errors.Wrap(err, "unable to parse health check interval variable")
		}
		interval = int32(parse.Seconds())
	}

	if composeHealthCheck.Retries != nil {
		retries = int32(*composeHealthCheck.Retries)
	}

	if composeHealthCheck.StartPeriod != nil {
		parse, err := time.ParseDuration(composeHealthCheck.StartPeriod.String())
		if err != nil {
			return kobject.HealthCheck{}, errors.Wrap(err, "unable to parse health check startPeriod variable")
		}
		startPeriod = int32(parse.Seconds())
	}

	// Due to docker/cli adding "CMD-SHELL" to the struct, we remove the first element of composeHealthCheck.Test
	return kobject.HealthCheck{
		Test:        composeHealthCheck.Test[1:],
		Timeout:     timeout,
		Interval:    interval,
		Retries:     retries,
		StartPeriod: startPeriod,
	}, nil
}

func dockerComposeToKomposeMapping(composeObject *types.Config) (kobject.KomposeObject, error) {

	// Step 1. Initialize what's going to be returned
	komposeObject := kobject.KomposeObject{
		ServiceConfigs: make(map[string]kobject.ServiceConfig),
		LoadedFrom:     "compose",
	}

	// Step 2. Parse through the object and convert it to kobject.KomposeObject!
	// Here we "clean up" the service configuration so we return something that includes
	// all relevant information as well as avoid the unsupported keys as well.
	for _, composeServiceConfig := range composeObject.Services {

		// Standard import
		// No need to modify before importation
		name := composeServiceConfig.Name
		serviceConfig := kobject.ServiceConfig{}
		serviceConfig.Image = composeServiceConfig.Image
		serviceConfig.WorkingDir = composeServiceConfig.WorkingDir
		serviceConfig.Annotations = map[string]string(composeServiceConfig.Labels)
		serviceConfig.CapAdd = composeServiceConfig.CapAdd
		serviceConfig.CapDrop = composeServiceConfig.CapDrop
		serviceConfig.Expose = composeServiceConfig.Expose
		serviceConfig.Privileged = composeServiceConfig.Privileged
		serviceConfig.User = composeServiceConfig.User
		serviceConfig.Stdin = composeServiceConfig.StdinOpen
		serviceConfig.Tty = composeServiceConfig.Tty
		serviceConfig.TmpFs = composeServiceConfig.Tmpfs
		serviceConfig.ContainerName = normalizeContainerNames(composeServiceConfig.ContainerName)
		serviceConfig.Command = composeServiceConfig.Entrypoint
		serviceConfig.Args = composeServiceConfig.Command
		serviceConfig.Labels = composeServiceConfig.Labels
		serviceConfig.HostName = composeServiceConfig.Hostname
		serviceConfig.DomainName = composeServiceConfig.DomainName

		//
		// Deploy keys
		//

		// mode:
		serviceConfig.DeployMode = composeServiceConfig.Deploy.Mode

		// HealthCheck
		if composeServiceConfig.HealthCheck != nil && !composeServiceConfig.HealthCheck.Disable {
			var err error
			serviceConfig.HealthChecks, err = parseHealthCheck(*composeServiceConfig.HealthCheck)
			if err != nil {
				return kobject.KomposeObject{}, errors.Wrap(err, "Unable to parse health check")
			}
		}

		if (composeServiceConfig.Deploy.Resources != types.Resources{}) {

			// memory:
			// TODO: Refactor yaml.MemStringorInt in kobject.go to int64
			// cpu:
			// convert to k8s format, for example: 0.5 = 500m
			// See: https://kubernetes.io/docs/concepts/configuration/manage-compute-resources-container/
			// "The expression 0.1 is equivalent to the expression 100m, which can be read as “one hundred millicpu”."

			// Since Deploy.Resources.Limits does not initialize, we must check type Resources before continuing
			if composeServiceConfig.Deploy.Resources.Limits != nil {
				serviceConfig.MemLimit = libcomposeyaml.MemStringorInt(composeServiceConfig.Deploy.Resources.Limits.MemoryBytes)

				if composeServiceConfig.Deploy.Resources.Limits.NanoCPUs != "" {
					cpuLimit, err := strconv.ParseFloat(composeServiceConfig.Deploy.Resources.Limits.NanoCPUs, 64)
					if err != nil {
						return kobject.KomposeObject{}, errors.Wrap(err, "Unable to convert cpu limits resources value")
					}
					serviceConfig.CPULimit = int64(cpuLimit * 1000)
				}
			}
			if composeServiceConfig.Deploy.Resources.Reservations != nil {
				serviceConfig.MemReservation = libcomposeyaml.MemStringorInt(composeServiceConfig.Deploy.Resources.Reservations.MemoryBytes)

				if composeServiceConfig.Deploy.Resources.Reservations.NanoCPUs != "" {
					cpuReservation, err := strconv.ParseFloat(composeServiceConfig.Deploy.Resources.Reservations.NanoCPUs, 64)
					if err != nil {
						return kobject.KomposeObject{}, errors.Wrap(err, "Unable to convert cpu limits reservation value")
					}
					serviceConfig.CPUReservation = int64(cpuReservation * 1000)
				}
			}
		}

		// restart-policy: deploy.restart_policy.condition will rewrite restart option
		// see: https://docs.docker.com/compose/compose-file/#restart_policy
		serviceConfig.Restart = composeServiceConfig.Restart
		if composeServiceConfig.Deploy.RestartPolicy != nil {
			serviceConfig.Restart = composeServiceConfig.Deploy.RestartPolicy.Condition
		}
		if serviceConfig.Restart == "unless-stopped" {
			log.Warnf("Restart policy 'unless-stopped' in service %s is not supported, convert it to 'always'", name)
			serviceConfig.Restart = "always"
		}

		// replicas:
		if composeServiceConfig.Deploy.Replicas != nil {
			serviceConfig.Replicas = int(*composeServiceConfig.Deploy.Replicas)
		}

		// placement:
		serviceConfig.Placement = loadV3Placement(composeServiceConfig.Deploy.Placement.Constraints)

		// TODO: Build is not yet supported, see:
		// https://github.com/docker/cli/blob/master/cli/compose/types/types.go#L9
		// We will have to *manually* add this / parse.
		serviceConfig.Build = composeServiceConfig.Build.Context
		serviceConfig.Dockerfile = composeServiceConfig.Build.Dockerfile
		serviceConfig.BuildArgs = composeServiceConfig.Build.Args
		serviceConfig.BuildLabels = composeServiceConfig.Build.Labels

		// Gather the environment values
		// DockerCompose uses map[string]*string while we use []string
		// So let's convert that using this hack
		// Note: unset env pick up the env value on host if exist
		for name, value := range composeServiceConfig.Environment {
			var env kobject.EnvVar
			if value != nil {
				env = kobject.EnvVar{Name: name, Value: *value}
			} else {
				result, ok := os.LookupEnv(name)
				if ok {
					env = kobject.EnvVar{Name: name, Value: result}
				} else {
					continue
				}
			}
			serviceConfig.Environment = append(serviceConfig.Environment, env)
		}

		// Get env_file
		serviceConfig.EnvFile = composeServiceConfig.EnvFile

		// Parse the ports
		// v3 uses a new format called "long syntax" starting in 3.2
		// https://docs.docker.com/compose/compose-file/#ports
		serviceConfig.Port = loadV3Ports(composeServiceConfig.Ports)

		// Parse the volumes
		// Again, in v3, we use the "long syntax" for volumes in terms of parsing
		// https://docs.docker.com/compose/compose-file/#long-syntax-3
		serviceConfig.VolList = loadV3Volumes(composeServiceConfig.Volumes)

		// Label handler
		// Labels used to influence conversion of kompose will be handled
		// from here for docker-compose. Each loader will have such handler.
		for key, value := range composeServiceConfig.Labels {
			switch key {
			case LabelServiceType:
				serviceType, err := handleServiceType(value)
				if err != nil {
					return kobject.KomposeObject{}, errors.Wrap(err, "handleServiceType failed")
				}

				serviceConfig.ServiceType = serviceType
			case LabelServiceExpose:
				serviceConfig.ExposeService = strings.Trim(strings.ToLower(value), " ,")
			case LabelServiceExposeTLSSecret:
				serviceConfig.ExposeServiceTLS = value
			case LabelImagePullSecret:
				serviceConfig.ImagePullSecret = value
			case LabelImagePullPolicy:
				serviceConfig.ImagePullPolicy = value
			}
		}

		if serviceConfig.ExposeService == "" && serviceConfig.ExposeServiceTLS != "" {
			return kobject.KomposeObject{}, errors.New("kompose.service.expose.tls-secret was specified without kompose.service.expose")
		}

		// Log if the name will been changed
		if normalizeServiceNames(name) != name {
			log.Infof("Service name in docker-compose has been changed from %q to %q", name, normalizeServiceNames(name))
		}

		serviceConfig.Configs = composeServiceConfig.Configs
		serviceConfig.ConfigsMetaData = composeObject.Configs
		if composeServiceConfig.Deploy.EndpointMode == "vip" {
			serviceConfig.ServiceType = string(api.ServiceTypeNodePort)
		}
		// Final step, add to the array!
		komposeObject.ServiceConfigs[normalizeServiceNames(name)] = serviceConfig
	}

	handleV3Volume(&komposeObject, &composeObject.Volumes)

	return komposeObject, nil
}

func handleV3Volume(komposeObject *kobject.KomposeObject, volumes *map[string]types.VolumeConfig) {
	for name := range komposeObject.ServiceConfigs {
		// retrieve volumes of service
		vols, err := retrieveVolume(name, *komposeObject)
		if err != nil {
			errors.Wrap(err, "could not retrieve vvolume")
		}
		for volName, vol := range vols {
			size, selector := getV3VolumeLabels(vol.VolumeName, volumes)
			if len(size) > 0 || len(selector) > 0 {
				// We can't assign value to struct field in map while iterating over it, so temporary variable `temp` is used here
				var temp = vols[volName]
				temp.PVCSize = size
				temp.SelectorValue = selector
				vols[volName] = temp
			}
		}
		// We can't assign value to struct field in map while iterating over it, so temporary variable `temp` is used here
		var temp = komposeObject.ServiceConfigs[name]
		temp.Volumes = vols
		komposeObject.ServiceConfigs[name] = temp
	}
}

func getV3VolumeLabels(name string, volumes *map[string]types.VolumeConfig) (string, string) {
	size, selector := "", ""

	if volume, ok := (*volumes)[name]; ok {
		for key, value := range volume.Labels {
			if key == "kompose.volume.size" {
				size = value
			} else if key == "kompose.volume.selector" {
				selector = value
			}
		}
	}

	return size, selector
}

func mergeComposeObject(oldCompose *types.Config, newCompose *types.Config) (*types.Config, error) {
	if oldCompose == nil || newCompose == nil {
		return nil, fmt.Errorf("Merge multiple compose error, compose config is nil")
	}
	oldComposeServiceNameMap := make(map[string]int, len(oldCompose.Services))
	for index, service := range oldCompose.Services {
		oldComposeServiceNameMap[service.Name] = index
	}

	for _, service := range newCompose.Services {
		index := 0
		if tmpIndex, ok := oldComposeServiceNameMap[service.Name]; !ok {
			oldCompose.Services = append(oldCompose.Services, service)
			continue
		} else {
			index = tmpIndex
		}
		tmpOldService := oldCompose.Services[index]
		if service.Build.Dockerfile != "" {
			tmpOldService.Build = service.Build
		}
		if len(service.CapAdd) != 0 {
			tmpOldService.CapAdd = service.CapAdd
		}
		if len(service.CapDrop) != 0 {
			tmpOldService.CapDrop = service.CapDrop
		}
		if service.CgroupParent != "" {
			tmpOldService.CgroupParent = service.CgroupParent
		}
		if len(service.Command) != 0 {
			tmpOldService.Command = service.Command
		}
		if len(service.Configs) != 0 {
			tmpOldService.Configs = service.Configs
		}
		if service.ContainerName != "" {
			tmpOldService.ContainerName = service.ContainerName
		}
		if service.CredentialSpec.File != "" || service.CredentialSpec.Registry != "" {
			tmpOldService.CredentialSpec = service.CredentialSpec
		}
		if len(service.DependsOn) != 0 {
			tmpOldService.DependsOn = service.DependsOn
		}
		if service.Deploy.Mode != "" {
			tmpOldService.Deploy = service.Deploy
		}
		if len(service.Devices) != 0 {
			tmpOldService.Devices = service.Devices
		}
		if len(service.DNS) != 0 {
			tmpOldService.DNS = service.DNS
		}
		if len(service.DNSSearch) != 0 {
			tmpOldService.DNSSearch = service.DNSSearch
		}
		if service.DomainName != "" {
			tmpOldService.DomainName = service.DomainName
		}
		if len(service.Entrypoint) != 0 {
			tmpOldService.Entrypoint = service.Entrypoint
		}
		if len(service.Environment) != 0 {
			tmpOldService.Environment = service.Environment
		}
		if len(service.EnvFile) != 0 {
			tmpOldService.EnvFile = service.EnvFile
		}
		if len(service.Expose) != 0 {
			tmpOldService.Expose = service.Expose
		}
		if len(service.ExternalLinks) != 0 {
			tmpOldService.ExternalLinks = service.ExternalLinks
		}
		if len(service.ExtraHosts) != 0 {
			tmpOldService.ExtraHosts = service.ExtraHosts
		}
		if service.Hostname != "" {
			tmpOldService.Hostname = service.Hostname
		}
		if service.HealthCheck != nil {
			tmpOldService.HealthCheck = service.HealthCheck
		}
		if service.Image != "" {
			tmpOldService.Image = service.Image
		}
		if service.Ipc != "" {
			tmpOldService.Ipc = service.Ipc
		}
		if len(service.Labels) != 0 {
			tmpOldService.Labels = service.Labels
		}
		if len(service.Links) != 0 {
			tmpOldService.Links = service.Links
		}
		if service.Logging != nil {
			tmpOldService.Logging = service.Logging
		}
		if service.MacAddress != "" {
			tmpOldService.MacAddress = service.MacAddress
		}
		if service.NetworkMode != "" {
			tmpOldService.NetworkMode = service.NetworkMode
		}
		if len(service.Networks) != 0 {
			tmpOldService.Networks = service.Networks
		}
		if service.Pid != "" {
			tmpOldService.Pid = service.Pid
		}
		if len(service.Ports) != 0 {
			tmpOldService.Ports = service.Ports
		}
		if service.Privileged != tmpOldService.Privileged {
			tmpOldService.Privileged = service.Privileged
		}
		if service.ReadOnly != tmpOldService.ReadOnly {
			tmpOldService.ReadOnly = service.ReadOnly
		}
		if service.Restart != "" {
			tmpOldService.Restart = service.Restart
		}
		if len(service.Secrets) != 0 {
			tmpOldService.Secrets = service.Secrets
		}
		if len(service.SecurityOpt) != 0 {
			tmpOldService.SecurityOpt = service.SecurityOpt
		}
		if service.StdinOpen != tmpOldService.StdinOpen {
			tmpOldService.StdinOpen = service.StdinOpen
		}
		if service.StopGracePeriod != nil {
			tmpOldService.StopGracePeriod = service.StopGracePeriod
		}
		if service.StopSignal != "" {
			tmpOldService.StopSignal = service.StopSignal
		}
		if len(service.Tmpfs) != 0 {
			tmpOldService.Tmpfs = service.Tmpfs
		}
		if service.Tty != tmpOldService.Tty {
			tmpOldService.Tty = service.Tty
		}
		if len(service.Ulimits) != 0 {
			tmpOldService.Ulimits = service.Ulimits
		}
		if service.User != "" {
			tmpOldService.User = service.User
		}
		if len(service.Volumes) != 0 {
			tmpOldService.Volumes = service.Volumes
		}
		if service.WorkingDir != "" {
			tmpOldService.WorkingDir = service.WorkingDir
		}
		oldCompose.Services[index] = tmpOldService
	}

	// Merge the networks information
	for idx, network := range newCompose.Networks {
		oldCompose.Networks[idx] = network
	}

	// Merge the volumes information
	for idx, volume := range newCompose.Volumes {
		oldCompose.Volumes[idx] = volume
	}

	// Merge the secrets information
	for idx, secret := range newCompose.Secrets {
		oldCompose.Secrets[idx] = secret
	}

	// Merge the configs information
	for idx, config := range newCompose.Configs {
		oldCompose.Configs[idx] = config
	}

	return oldCompose, nil
}

func checkUnsupportedKeyForV3(composeObject *types.Config) []string {
	if composeObject == nil {
		return []string{}
	}

	var keysFound []string

	for _, service := range composeObject.Services {
		//For short syntax, volume mount path must be /, but this will cause pod create fail in kubernetes
		//So we ignore this attribute
		for _, tmpConfig := range service.Configs {
			if tmpConfig.Mode == nil {
				keysFound = append(keysFound, "short syntax config")
			} else {
				if tmpConfig.GID != "" {
					keysFound = append(keysFound, "long syntax config gid")
				}
				if tmpConfig.UID != "" {
					keysFound = append(keysFound, "long syntax config uid")
				}
			}
		}

		if service.CredentialSpec.Registry != "" || service.CredentialSpec.File != "" {
			keysFound = append(keysFound, "credential_spec")

		}
	}

	for _, config := range composeObject.Configs {
		if config.External.External {
			keysFound = append(keysFound, "external config")
		}
	}

	return keysFound
}