package main

import (
	"context"
	"fmt"
	"net/url"
	"os"
	"path"
	"path/filepath"
	"sigs.k8s.io/yaml"
	"strings"
	"time"

	"github.com/spf13/cobra"
	corev1 "k8s.io/api/core/v1"
	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
	"k8s.io/apimachinery/pkg/types"
	"k8s.io/apimachinery/pkg/util/wait"
	"sigs.k8s.io/controller-runtime/pkg/client"

	kustomizev1 "github.com/fluxcd/kustomize-controller/api/v1alpha1"
	sourcev1 "github.com/fluxcd/source-controller/api/v1alpha1"
)

var bootstrapCmd = &cobra.Command{
	Use:   "bootstrap",
	Short: "Bootstrap commands",
}

var (
	bootstrapVersion string
)

const (
	bootstrapBranch                = "master"
	bootstrapInstallManifest       = "toolkit-components.yaml"
	bootstrapSourceManifest        = "toolkit-source.yaml"
	bootstrapKustomizationManifest = "toolkit-kustomization.yaml"
)

func init() {
	bootstrapCmd.PersistentFlags().StringVar(&bootstrapVersion, "version", "master", "toolkit tag or branch")

	rootCmd.AddCommand(bootstrapCmd)
}

func generateInstallManifests(targetPath, namespace, tmpDir string) (string, error) {
	tkDir := path.Join(tmpDir, ".tk")
	defer os.RemoveAll(tkDir)

	if err := os.MkdirAll(tkDir, os.ModePerm); err != nil {
		return "", fmt.Errorf("generating manifests failed: %w", err)
	}

	if err := genInstallManifests(bootstrapVersion, namespace, components, tkDir); err != nil {
		return "", fmt.Errorf("generating manifests failed: %w", err)
	}

	manifestsDir := path.Join(tmpDir, targetPath, namespace)
	if err := os.MkdirAll(manifestsDir, os.ModePerm); err != nil {
		return "", fmt.Errorf("generating manifests failed: %w", err)
	}

	manifest := path.Join(manifestsDir, bootstrapInstallManifest)
	if err := buildKustomization(tkDir, manifest); err != nil {
		return "", fmt.Errorf("build kustomization failed: %w", err)
	}

	return manifest, nil
}

func applyInstallManifests(ctx context.Context, manifestPath string, components []string) error {
	command := fmt.Sprintf("kubectl apply -f %s", manifestPath)
	if _, err := utils.execCommand(ctx, ModeOS, command); err != nil {
		return fmt.Errorf("install failed")
	}

	for _, deployment := range components {
		command = fmt.Sprintf("kubectl -n %s rollout status deployment %s --timeout=%s",
			namespace, deployment, timeout.String())
		if _, err := utils.execCommand(ctx, ModeOS, command); err != nil {
			return fmt.Errorf("install failed")
		}
	}
	return nil
}

func generateSyncManifests(url, name, namespace, targetPath, tmpDir string, interval time.Duration) error {
	gvk := sourcev1.GroupVersion.WithKind("GitRepository")
	gitRepository := sourcev1.GitRepository{
		TypeMeta: metav1.TypeMeta{
			Kind:       gvk.Kind,
			APIVersion: gvk.GroupVersion().String(),
		},
		ObjectMeta: metav1.ObjectMeta{
			Name:      name,
			Namespace: namespace,
		},
		Spec: sourcev1.GitRepositorySpec{
			URL: url,
			Interval: metav1.Duration{
				Duration: interval,
			},
			Reference: &sourcev1.GitRepositoryRef{
				Branch: "master",
			},
			SecretRef: &corev1.LocalObjectReference{
				Name: name,
			},
		},
	}

	gitData, err := yaml.Marshal(gitRepository)
	if err != nil {
		return err
	}

	if err := utils.writeFile(string(gitData), filepath.Join(tmpDir, targetPath, namespace, bootstrapSourceManifest)); err != nil {
		return err
	}

	gvk = kustomizev1.GroupVersion.WithKind("Kustomization")
	emptyAPIGroup := ""
	kustomization := kustomizev1.Kustomization{
		TypeMeta: metav1.TypeMeta{
			Kind:       gvk.Kind,
			APIVersion: gvk.GroupVersion().String(),
		},
		ObjectMeta: metav1.ObjectMeta{
			Name:      name,
			Namespace: namespace,
		},
		Spec: kustomizev1.KustomizationSpec{
			Interval: metav1.Duration{
				Duration: 10 * time.Minute,
			},
			Path:  fmt.Sprintf("./%s", strings.TrimPrefix(targetPath, "./")),
			Prune: true,
			SourceRef: corev1.TypedLocalObjectReference{
				APIGroup: &emptyAPIGroup,
				Kind:     "GitRepository",
				Name:     name,
			},
		},
	}

	ksData, err := yaml.Marshal(kustomization)
	if err != nil {
		return err
	}

	if err := utils.writeFile(string(ksData), filepath.Join(tmpDir, targetPath, namespace, bootstrapKustomizationManifest)); err != nil {
		return err
	}

	return nil
}

func applySyncManifests(ctx context.Context, kubeClient client.Client, name, namespace, targetPath, tmpDir string) error {
	command := fmt.Sprintf("kubectl apply -f %s", filepath.Join(tmpDir, targetPath, namespace))
	if _, err := utils.execCommand(ctx, ModeStderrOS, command); err != nil {
		return err
	}

	logWaiting("waiting for cluster sync")

	if err := wait.PollImmediate(pollInterval, timeout,
		isGitRepositoryReady(ctx, kubeClient, name, namespace)); err != nil {
		return err
	}

	if err := wait.PollImmediate(pollInterval, timeout,
		isKustomizationReady(ctx, kubeClient, name, namespace)); err != nil {
		return err
	}

	return nil
}

func shouldInstallManifests(ctx context.Context, kubeClient client.Client, namespace string) bool {
	namespacedName := types.NamespacedName{
		Namespace: namespace,
		Name:      namespace,
	}
	var kustomization kustomizev1.Kustomization
	if err := kubeClient.Get(ctx, namespacedName, &kustomization); err != nil {
		return true
	}

	return kustomization.Status.LastAppliedRevision == ""
}

func shouldCreateDeployKey(ctx context.Context, kubeClient client.Client, namespace string) bool {
	namespacedName := types.NamespacedName{
		Namespace: namespace,
		Name:      namespace,
	}

	var existing corev1.Secret
	if err := kubeClient.Get(ctx, namespacedName, &existing); err != nil {
		return true
	}
	return false
}

func generateDeployKey(ctx context.Context, kubeClient client.Client, url *url.URL, namespace string) (string, error) {
	pair, err := generateKeyPair(ctx)
	if err != nil {
		return "", err
	}

	hostKey, err := scanHostKey(ctx, url)
	if err != nil {
		return "", err
	}

	secret := corev1.Secret{
		ObjectMeta: metav1.ObjectMeta{
			Name:      namespace,
			Namespace: namespace,
		},
		StringData: map[string]string{
			"identity":     string(pair.PrivateKey),
			"identity.pub": string(pair.PublicKey),
			"known_hosts":  string(hostKey),
		},
	}
	if err := upsertSecret(ctx, kubeClient, secret); err != nil {
		return "", err
	}

	return string(pair.PublicKey), nil
}