//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 main

import (
	"flag"
	"io/ioutil"
	"os"
	"path/filepath"
	"text/template"

	"k8s.io/apimachinery/pkg/runtime"
	"k8s.io/klog"
	cdicluster "kubevirt.io/containerized-data-importer/pkg/operator/resources/cluster"
	cdinamespaced "kubevirt.io/containerized-data-importer/pkg/operator/resources/namespaced"
	cdioperator "kubevirt.io/containerized-data-importer/pkg/operator/resources/operator"
	"kubevirt.io/containerized-data-importer/tools/util"
)

type templateData struct {
	DockerRepo             string
	DockerTag              string
	OperatorVersion        string
	DeployClusterResources string
	OperatorImage          string
	ControllerImage        string
	ImporterImage          string
	ClonerImage            string
	APIServerImage         string
	UploadProxyImage       string
	UploadServerImage      string
	Verbosity              string
	PullPolicy             string
	Namespace              string
	GeneratedManifests     map[string]string
}

var (
	dockerRepo             = flag.String("docker-repo", "", "")
	dockertag              = flag.String("docker-tag", "", "")
	operatorVersion        = flag.String("operator-version", "", "")
	genManifestsPath       = flag.String("generated-manifests-path", "", "")
	deployClusterResources = flag.String("deploy-cluster-resources", "", "")
	operatorImage          = flag.String("operator-image", "", "")
	controllerImage        = flag.String("controller-image", "", "")
	importerImage          = flag.String("importer-image", "", "")
	clonerImage            = flag.String("cloner-image", "", "")
	apiServerImage         = flag.String("apiserver-image", "", "")
	uploadProxyImage       = flag.String("uploadproxy-image", "", "")
	uploadServerImage      = flag.String("uploadserver-image", "", "")
	verbosity              = flag.String("verbosity", "1", "")
	pullPolicy             = flag.String("pull-policy", "", "")
	namespace              = flag.String("namespace", "", "")
)

func main() {
	templFile := flag.String("template", "", "")
	resourceType := flag.String("resource-type", "", "")
	resourceGroup := flag.String("resource-group", "everything", "")
	flag.Parse()

	klogFlags := flag.NewFlagSet("klog", flag.ExitOnError)
	klog.InitFlags(klogFlags)
	flag.CommandLine.VisitAll(func(f1 *flag.Flag) {
		f2 := klogFlags.Lookup(f1.Name)
		if f2 != nil {
			value := f1.Value.String()
			f2.Value.Set(value)
		}
	})

	if *templFile != "" {
		generateFromFile(*templFile)
		return
	}

	generateFromCode(*resourceType, *resourceGroup)
}

func generateFromFile(templFile string) {
	data := &templateData{
		Verbosity:              *verbosity,
		DockerRepo:             *dockerRepo,
		DockerTag:              *dockertag,
		DeployClusterResources: *deployClusterResources,
		OperatorImage:          *operatorImage,
		ControllerImage:        *controllerImage,
		ImporterImage:          *importerImage,
		ClonerImage:            *clonerImage,
		APIServerImage:         *apiServerImage,
		UploadProxyImage:       *uploadProxyImage,
		UploadServerImage:      *uploadServerImage,
		PullPolicy:             *pullPolicy,
		Namespace:              *namespace,
	}

	file, err := os.Open(templFile)
	if err != nil {
		klog.Fatalf("Failed to open file %s: %v", templFile, err)
	}
	defer file.Close()

	// Read generated manifests and populate templated manifest
	genDir := *genManifestsPath
	data.GeneratedManifests = make(map[string]string)
	manifests, err := ioutil.ReadDir(genDir)
	if err != nil {
		klog.Fatalf("Failed to read directory %s: %v", genDir, err)
	}

	for _, manifest := range manifests {
		if manifest.IsDir() {
			continue
		}
		b, err := ioutil.ReadFile(filepath.Join(genDir, manifest.Name()))
		if err != nil {
			klog.Fatalf("Failed to read file %s: %v", templFile, err)
		}

		data.GeneratedManifests[manifest.Name()] = string(b)
	}

	tmpl := template.Must(template.ParseFiles(templFile))
	err = tmpl.Execute(os.Stdout, data)
	if err != nil {
		klog.Fatalf("Error executing template: %v", err)
	}
}

type resourceGetter func(string) ([]runtime.Object, error)

var resourceGetterMap = map[string]resourceGetter{
	"cluster":    getClusterResources,
	"namespaced": getNamespacedResources,
	"operator":   getOperatorResources,
}

func generateFromCode(resourceType, resourceGroup string) {
	f, ok := resourceGetterMap[resourceType]
	if !ok {
		klog.Fatalf("Unknown resource type %s", resourceType)
	}

	resources, err := f(resourceGroup)
	if err != nil {
		klog.Fatalf("Error getting resources: %v", err)
	}

	for _, resource := range resources {
		err := util.MarshallObject(resource, os.Stdout)
		if err != nil {
			klog.Fatalf("Error marshalling resource: %v", err)
		}
	}
}

func getOperatorResources(resourceGroup string) ([]runtime.Object, error) {
	args := &cdioperator.FactoryArgs{
		NamespacedArgs: cdinamespaced.FactoryArgs{
			Verbosity:              *verbosity,
			OperatorVersion:        *operatorVersion,
			DeployClusterResources: *deployClusterResources,
			ControllerImage:        *controllerImage,
			ImporterImage:          *importerImage,
			ClonerImage:            *clonerImage,
			APIServerImage:         *apiServerImage,
			UploadProxyImage:       *uploadProxyImage,
			UploadServerImage:      *uploadServerImage,
			PullPolicy:             *pullPolicy,
			Namespace:              *namespace,
		},
		Image: *operatorImage,
	}

	return cdioperator.CreateOperatorResourceGroup(resourceGroup, args)
}

func getClusterResources(codeGroup string) ([]runtime.Object, error) {
	args := &cdicluster.FactoryArgs{
		Namespace: *namespace,
	}

	return cdicluster.CreateStaticResourceGroup(codeGroup, args)
}

func getNamespacedResources(codeGroup string) ([]runtime.Object, error) {
	args := &cdinamespaced.FactoryArgs{
		Verbosity:         *verbosity,
		OperatorVersion:   *operatorVersion,
		ControllerImage:   *controllerImage,
		ImporterImage:     *importerImage,
		ClonerImage:       *clonerImage,
		APIServerImage:    *apiServerImage,
		UploadProxyImage:  *uploadProxyImage,
		UploadServerImage: *uploadServerImage,
		PullPolicy:        *pullPolicy,
		Namespace:         *namespace,
	}

	return cdinamespaced.CreateResourceGroup(codeGroup, args)
}