package state

import (
	"context"
	"fmt"
	"os"
	"path/filepath"
	"slices"
	"sort"
	"strings"
	"time"

	"github.com/helmfile/chartify"
	"helm.sh/helm/v4/pkg/storage/driver"

	"github.com/helmfile/helmfile/pkg/filesystem"
	"github.com/helmfile/helmfile/pkg/helmexec"
	"github.com/helmfile/helmfile/pkg/kubedog"
	"github.com/helmfile/helmfile/pkg/remote"
	"github.com/helmfile/helmfile/pkg/resource"
	"github.com/helmfile/helmfile/pkg/tmpl"
)

type Dependency struct {
	Chart   string `yaml:"chart"`
	Version string `yaml:"version"`
	Alias   string `yaml:"alias"`
}

func (st *HelmState) appendHelmXFlags(flags []string, release *ReleaseSpec) []string {
	for _, adopt := range release.Adopt {
		flags = append(flags, "--adopt", adopt)
	}

	return flags
}

func formatLabels(labels map[string]string) string {
	var labelsList, keys []string
	for k := range labels {
		if k == "" || slices.Contains(driver.GetSystemLabels(), k) {
			continue
		}

		keys = append(keys, k)
	}
	sort.Strings(keys)

	if len(keys) == 0 {
		return ""
	}

	for _, k := range keys {
		val := labels[k]
		labelsList = append(labelsList, fmt.Sprintf("%s=%s", k, val))
	}
	return strings.Join(labelsList, ",")
}

// append labels flags to helm flags, starting from helm v3.13.0
func (st *HelmState) appendLabelsFlags(flags []string, helm helmexec.Interface, release *ReleaseSpec, syncReleaseLabels bool) []string {
	if !helm.IsVersionAtLeast("3.13.0") {
		return flags
	}
	isSyncReleaseLabels := false
	switch {
	// Check if SyncReleaseLabels is true in the release spec.
	case release.SyncReleaseLabels != nil && *release.SyncReleaseLabels:
		isSyncReleaseLabels = true
	// Check if syncReleaseLabels argument is true.
	case syncReleaseLabels:
		isSyncReleaseLabels = true
	// Check if SyncReleaseLabels is true in HelmDefaults.
	case st.HelmDefaults.SyncReleaseLabels != nil && *st.HelmDefaults.SyncReleaseLabels:
		isSyncReleaseLabels = true
	}
	if isSyncReleaseLabels {
		labels := formatLabels(release.Labels)
		if labels != "" {
			flags = append(flags, "--labels", labels)
		}
	}
	return flags
}

// append post-renderer flags to helm flags
func (st *HelmState) appendPostRenderFlags(flags []string, release *ReleaseSpec, postRenderer string, helm helmexec.Interface) []string {
	var rendererPath string
	switch {
	// postRenderer arg comes from cmd flag.
	case release.PostRenderer != nil && *release.PostRenderer != "":
		rendererPath = *release.PostRenderer
	case postRenderer != "":
		rendererPath = postRenderer
	case st.HelmDefaults.PostRenderer != nil && *st.HelmDefaults.PostRenderer != "":
		rendererPath = *st.HelmDefaults.PostRenderer
	}

	if rendererPath != "" {
		// For Helm 4, convert the bash script path to a plugin name
		if helm != nil && !helm.IsHelm3() {
			// Check if this is a bash script path that needs conversion
			if strings.HasSuffix(rendererPath, ".bash") || strings.HasSuffix(rendererPath, ".sh") {
				// Extract the base name (e.g., "add-cm1" from "../../postrenderers/add-cm1.bash")
				baseName := filepath.Base(rendererPath)
				baseName = strings.TrimSuffix(baseName, filepath.Ext(baseName))

				// For Helm 4, use just the plugin name
				// From: ../../postrenderers/add-cm1.bash
				// To: add-cm1 (assuming the plugin is installed with this name)
				rendererPath = baseName
			}
		}
		flags = append(flags, "--post-renderer", rendererPath)
	}
	return flags
}

// append post-renderer-args flags to helm flags
func (st *HelmState) appendPostRenderArgsFlags(flags []string, release *ReleaseSpec, postRendererArgs []string) ([]string, error) {
	postRendererArgsFlags := []string{}
	switch {
	case len(release.PostRendererArgs) != 0:
		postRendererArgsFlags = release.PostRendererArgs
	case len(postRendererArgs) != 0:
		postRendererArgsFlags = postRendererArgs
	case len(st.HelmDefaults.PostRendererArgs) != 0:
		rendered, err := st.renderPostRendererArgs(release, st.HelmDefaults.PostRendererArgs)
		if err != nil {
			return nil, err
		}
		postRendererArgsFlags = rendered
	}
	for _, arg := range postRendererArgsFlags {
		if arg != "" {
			flags = append(flags, "--post-renderer-args="+arg)
		}
	}
	return flags, nil
}

func (st *HelmState) renderPostRendererArgs(release *ReleaseSpec, args []string) ([]string, error) {
	vals := st.RenderedValues
	if vals == nil {
		vals = make(map[string]any)
	}

	fs := st.fs
	if fs == nil {
		fs = filesystem.DefaultFileSystem()
	}

	tmplData := st.createReleaseTemplateData(release, vals)
	renderer := tmpl.NewFileRenderer(fs, st.basePath, tmplData)

	result := make([]string, 0, len(args))
	for _, arg := range args {
		rendered, err := renderer.RenderTemplateContentToString([]byte(arg))
		if err != nil {
			return nil, fmt.Errorf("failed rendering postRendererArg %q for release %q: %w", arg, release.Name, err)
		}
		result = append(result, rendered)
	}

	return result, nil
}

// append skip-schema-validation flags to helm flags
func (st *HelmState) appendSkipSchemaValidationFlags(flags []string, release *ReleaseSpec, skipSchemaValidation bool) []string {
	if st.shouldSkipSchemaValidation(release, skipSchemaValidation) {
		flags = append(flags, "--skip-schema-validation")
	}
	return flags
}

func (st *HelmState) shouldSkipSchemaValidation(release *ReleaseSpec, skipSchemaValidation bool) bool {
	switch {
	// Check if SkipSchemaValidation is true in the release spec.
	case release.SkipSchemaValidation != nil && *release.SkipSchemaValidation:
		return true
	// Check if skipSchemaValidation argument is true.
	case skipSchemaValidation:
		return true
	// Check if SkipSchemaValidation is true in HelmDefaults.
	case st.HelmDefaults.SkipSchemaValidation != nil && *st.HelmDefaults.SkipSchemaValidation:
		return true
	default:
		return false
	}
}

// append suppress-output-line-regex flags to helm diff flags
func (st *HelmState) appendSuppressOutputLineRegexFlags(flags []string, release *ReleaseSpec, suppressOutputLineRegex []string) []string {
	suppressOutputLineRegexFlags := []string{}
	switch {
	case len(release.SuppressOutputLineRegex) != 0:
		suppressOutputLineRegexFlags = release.SuppressOutputLineRegex
	case len(suppressOutputLineRegex) != 0:
		suppressOutputLineRegexFlags = suppressOutputLineRegex
	case len(st.HelmDefaults.SuppressOutputLineRegex) != 0:
		suppressOutputLineRegexFlags = st.HelmDefaults.SuppressOutputLineRegex
	}
	for _, arg := range suppressOutputLineRegexFlags {
		if arg != "" {
			flags = append(flags, "--suppress-output-line-regex", arg)
		}
	}
	return flags
}

func (st *HelmState) appendWaitForJobsFlags(flags []string, release *ReleaseSpec, ops *SyncOpts) []string {
	if st.shouldUseKubedog(release, ops) {
		return flags
	}

	switch {
	case release.WaitForJobs != nil && *release.WaitForJobs:
		flags = append(flags, "--wait-for-jobs")
	case ops != nil && ops.WaitForJobs:
		flags = append(flags, "--wait-for-jobs")
	case release.WaitForJobs == nil && st.HelmDefaults.WaitForJobs:
		flags = append(flags, "--wait-for-jobs")
	}

	return flags
}

func (st *HelmState) shouldUseKubedog(release *ReleaseSpec, ops *SyncOpts) bool {
	return st.getTrackMode(release, ops) == string(kubedog.TrackModeKubedog)
}

func (st *HelmState) shouldFailOnTrackError(release *ReleaseSpec, ops *SyncOpts) bool {
	if release.TrackFailOnError != nil {
		return *release.TrackFailOnError
	}
	if ops != nil {
		return ops.TrackFailOnError
	}
	return false
}

// trackReleaseIfEnabled performs kubedog tracking for a release if trackMode is "kubedog".
// It returns a ReleaseError if tracking fails and shouldFailOnTrackError is true.
// The caller is responsible for mutating affectedReleases when needed.
func (st *HelmState) trackReleaseIfEnabled(ctx context.Context, release *ReleaseSpec, helm helmexec.Interface, opts *SyncOpts) *ReleaseError {
	if !st.shouldUseKubedog(release, opts) {
		return nil
	}
	if trackErr := st.trackWithKubedog(ctx, release, helm, opts); trackErr != nil {
		st.logger.Warnf("kubedog tracking failed for release %s: %v", release.Name, trackErr)
		if st.shouldFailOnTrackError(release, opts) {
			return newReleaseFailedError(release, trackErr)
		}
	}
	return nil
}

func (st *HelmState) getTrackMode(release *ReleaseSpec, ops *SyncOpts) string {
	trackMode := release.TrackMode
	if trackMode == "" && ops != nil && ops.TrackMode != "" {
		trackMode = ops.TrackMode
	}
	if trackMode == "" {
		trackMode = st.HelmDefaults.TrackMode
	}
	if trackMode == "" {
		trackMode = string(kubedog.TrackModeHelm)
	}
	return trackMode
}

func (st *HelmState) appendWaitFlags(flags []string, helm helmexec.Interface, release *ReleaseSpec, ops *SyncOpts) []string {
	if st.shouldUseKubedog(release, ops) {
		return flags
	}

	shouldWait := false
	switch {
	case release.Wait != nil && *release.Wait:
		shouldWait = true
	case ops != nil && ops.Wait:
		shouldWait = true
	case release.Wait == nil && st.HelmDefaults.Wait:
		shouldWait = true
	}

	if shouldWait {
		trackMode := st.getTrackMode(release, ops)
		if trackMode == string(kubedog.TrackModeHelmLegacy) {
			if helm != nil && helm.IsHelm4() {
				flags = append(flags, "--wait=legacy")
			} else {
				if st.logger != nil {
					st.logger.Warnf("trackMode 'helm-legacy' requires Helm v4, falling back to regular --wait for release %s", release.Name)
				}
				flags = append(flags, "--wait")
			}
		} else {
			flags = append(flags, "--wait")
		}
	}

	return flags
}

// append post-renderer flags to helm flags
func (st *HelmState) appendCascadeFlags(flags []string, helm helmexec.Interface, release *ReleaseSpec, cascade string) []string {
	// see https://github.com/helm/helm/releases/tag/v3.12.1
	if !helm.IsVersionAtLeast("3.12.1") {
		return flags
	}
	switch {
	// postRenderer arg comes from cmd flag.
	case release.Cascade != nil && *release.Cascade != "":
		flags = append(flags, "--cascade", *release.Cascade)
	case cascade != "":
		flags = append(flags, "--cascade", cascade)
	case st.HelmDefaults.Cascade != nil && *st.HelmDefaults.Cascade != "":
		flags = append(flags, "--cascade", *st.HelmDefaults.Cascade)
	}
	return flags
}

// append hide-notes flags to helm flags
func (st *HelmState) appendHideNotesFlags(flags []string, helm helmexec.Interface, ops *SyncOpts) []string {
	if ops == nil {
		return flags
	}
	// see https://github.com/helm/helm/releases/tag/v3.16.0
	if !helm.IsVersionAtLeast("3.16.0") {
		return flags
	}
	switch {
	case ops.HideNotes:
		flags = append(flags, "--hide-notes")
	}
	return flags
}

// append take-ownership flags to helm flags
func (st *HelmState) appendTakeOwnershipFlagsForUpgrade(flags []string, helm helmexec.Interface, release *ReleaseSpec, takeOwnership bool) []string {
	// see https://github.com/helm/helm/releases/tag/v3.17.0
	if !helm.IsVersionAtLeast("3.17.0") {
		return flags
	}
	switch {
	case release.TakeOwnership != nil && *release.TakeOwnership:
		flags = append(flags, "--take-ownership")
	case takeOwnership:
		flags = append(flags, "--take-ownership")
	case st.HelmDefaults.TakeOwnership != nil && *st.HelmDefaults.TakeOwnership:
		flags = append(flags, "--take-ownership")
	}
	return flags
}

// append show-only flags to helm flags
func (st *HelmState) appendShowOnlyFlags(flags []string, showOnly []string) []string {
	showOnlyFlags := []string{}
	if len(showOnly) != 0 {
		showOnlyFlags = showOnly
	}
	for _, arg := range showOnlyFlags {
		if arg != "" {
			flags = append(flags, "--show-only", arg)
		}
	}
	return flags
}

type Chartify struct {
	Opts                     *chartify.ChartifyOpts
	Clean                    func()
	NeedsChartifyForLocalDir bool
}

func (st *HelmState) downloadChartWithGoGetter(r *ReleaseSpec) (string, error) {
	var pathElems []string

	if r.Namespace != "" {
		pathElems = append(pathElems, r.Namespace)
	}

	if r.KubeContext != "" {
		pathElems = append(pathElems, r.KubeContext)
	}

	pathElems = append(pathElems, r.Name)

	cacheDir := filepath.Join(pathElems...)

	return st.goGetterChart(r.Chart, r.Directory, cacheDir, r.ForceGoGetter)
}

func (st *HelmState) goGetterChart(chart, dir, cacheDir string, force bool) (string, error) {
	if dir != "" && chart == "" {
		chart = dir
	}

	_, err := remote.Parse(chart)
	if err != nil {
		if force {
			return "", fmt.Errorf("Parsing url from dir failed due to error %q.\nContinuing the process assuming this is a regular Helm chart or a local dir.", err.Error())
		}
	} else {
		r := remote.NewRemote(st.logger, "", st.fs)

		fetchedDir, err := r.Fetch(chart, cacheDir)
		if err != nil {
			return "", fmt.Errorf("fetching %q: %v", chart, err)
		}

		chart = fetchedDir
	}

	return chart, nil
}

func (st *HelmState) PrepareChartify(helm helmexec.Interface, release *ReleaseSpec, chart string, workerIndex int) (*Chartify, func(), error) {
	c := &Chartify{
		Opts: &chartify.ChartifyOpts{
			WorkaroundOutputDirIssue:    true,
			EnableKustomizeAlphaPlugins: true,
			ChartVersion:                release.Version,
			Namespace:                   release.Namespace,
			ID:                          ReleaseToID(release),
		},
	}

	var filesNeedCleaning []string

	clean := func() {
		st.removeFiles(filesNeedCleaning)
	}

	var shouldRun bool

	dir := chart
	if !filepath.IsAbs(chart) {
		dir = filepath.Join(st.basePath, chart)
	}
	if stat, _ := os.Stat(dir); stat != nil && stat.IsDir() {
		if exists, err := st.fs.FileExists(filepath.Join(dir, "Chart.yaml")); err == nil && !exists {
			shouldRun = true
			c.NeedsChartifyForLocalDir = true
		}
	}

	for _, d := range release.Dependencies {
		chart := d.Chart
		normalizedChart := normalizeChart(st.basePath, chart)
		if st.fs.DirectoryExistsAt(normalizedChart) {
			var err error

			// Otherwise helm-dependency-up on the temporary chart generated by chartify ends up errors like:
			//   Error: directory /tmp/chartify945964195/myapp-57fb4495cf/test/integration/charts/httpbin not found]
			// which is due to that the temporary chart is generated outside of the current working directory/basePath,
			// and therefore the relative path in `chart` points to somewhere inexistent.
			chart, err = filepath.Abs(filepath.Join(st.basePath, chart))
			if err != nil {
				return nil, clean, err
			}
		} else if rewritten, ok := st.resolveOCIAdhocDepChart(d.Chart); ok {
			st.logger.Debugf("ad-hoc dependency %q rewritten to %q (matched OCI repo entry)", d.Chart, rewritten)
			chart = rewritten
		}

		c.Opts.AdhocChartDependencies = append(c.Opts.AdhocChartDependencies, chartify.ChartDependency{
			Alias:   d.Alias,
			Chart:   chart,
			Version: d.Version,
		})

		shouldRun = true
	}

	jsonPatches := release.JSONPatches
	if len(jsonPatches) > 0 {
		generatedFiles, err := st.generateTemporaryReleaseValuesFiles(release, jsonPatches)
		if err != nil {
			return nil, clean, err
		}

		filesNeedCleaning = append(filesNeedCleaning, generatedFiles...)

		c.Opts.JsonPatches = append(c.Opts.JsonPatches, generatedFiles...)

		shouldRun = true
	}

	strategicMergePatches := release.StrategicMergePatches
	if len(strategicMergePatches) > 0 {
		generatedFiles, err := st.generateTemporaryReleaseValuesFiles(release, strategicMergePatches)
		if err != nil {
			return nil, clean, err
		}

		c.Opts.StrategicMergePatches = append(c.Opts.StrategicMergePatches, generatedFiles...)

		filesNeedCleaning = append(filesNeedCleaning, generatedFiles...)

		shouldRun = true
	}

	transformers := release.Transformers
	if len(transformers) > 0 {
		generatedFiles, err := st.generateTemporaryReleaseValuesFiles(release, transformers)
		if err != nil {
			return nil, clean, err
		}

		c.Opts.Transformers = append(c.Opts.Transformers, generatedFiles...)

		filesNeedCleaning = append(filesNeedCleaning, generatedFiles...)

		shouldRun = true
	}

	if release.ForceNamespace != "" {
		c.Opts.OverrideNamespace = release.ForceNamespace

		shouldRun = true
	}

	if shouldRun {
		st.logger.Debugf("Chartify process for %s", dir)
		generatedFiles, err := st.generateValuesFiles(helm, release, workerIndex)
		if err != nil {
			return nil, clean, err
		}

		filesNeedCleaning = append(filesNeedCleaning, generatedFiles...)

		c.Opts.ValuesFiles = generatedFiles
		setFlags, err := st.setFlags(release.SetValues)
		if err != nil {
			return nil, clean, fmt.Errorf("rendering set value entry for release %s: %v", release.Name, err)
		}
		c.Opts.SetFlags = setFlags
		c.Opts.TemplateData = st.newReleaseTemplateData(release)
		c.Opts.TemplateFuncs = st.newReleaseTemplateFuncMap(dir)

		return c, clean, nil
	}

	return nil, clean, nil
}

func (st *HelmState) trackWithKubedog(ctx context.Context, release *ReleaseSpec, helm helmexec.Interface, ops *SyncOpts) error {
	timeout := 5 * time.Minute
	if release.TrackTimeout != nil && *release.TrackTimeout > 0 {
		timeout = time.Duration(*release.TrackTimeout) * time.Second
	} else if ops != nil && ops.TrackTimeout > 0 {
		timeout = time.Duration(ops.TrackTimeout) * time.Second
	}

	trackLogs := release.TrackLogs != nil && *release.TrackLogs
	if release.TrackLogs == nil && ops != nil {
		trackLogs = ops.TrackLogs
	}

	filterConfig := &resource.FilterConfig{
		TrackKinds:     release.TrackKinds,
		SkipKinds:      release.SkipKinds,
		TrackResources: convertTrackResources(release.TrackResources),
	}

	kubeContext := st.getKubeContext(release)

	trackOpts := kubedog.NewTrackOptions().
		WithTimeout(timeout).
		WithLogs(trackLogs).
		WithFilterConfig(filterConfig)

	tracker, err := kubedog.NewTracker(&kubedog.TrackerConfig{
		Logger:       st.logger,
		Namespace:    release.Namespace,
		KubeContext:  kubeContext,
		Kubeconfig:   st.kubeconfig,
		TrackOptions: trackOpts,
		KubedogQPS:   release.KubedogQPS,
		KubedogBurst: release.KubedogBurst,
	})
	if err != nil {
		return fmt.Errorf("failed to create kubedog tracker: %w", err)
	}

	resources, err := st.getReleaseResources(ctx, release, helm)
	if err != nil {
		return fmt.Errorf("failed to get release resources: %w", err)
	}

	if len(resources) == 0 {
		st.logger.Infof("No trackable resources found for release %s", release.Name)
		return nil
	}

	st.logger.Infof("Tracking %d resources from release %s with kubedog", len(resources), release.Name)

	if err := tracker.TrackResources(ctx, resources); err != nil {
		return fmt.Errorf("kubedog tracking failed for release %s: %w", release.Name, err)
	}

	return nil
}

func (st *HelmState) getReleaseResources(_ context.Context, release *ReleaseSpec, helm helmexec.Interface) ([]*resource.Resource, error) {
	st.logger.Debugf("Getting resources for release %s", release.Name)

	manifest, namespace, err := st.getReleaseManifest(release, helm)
	if err != nil {
		return nil, fmt.Errorf("failed to get release manifest: %w", err)
	}

	if len(manifest) == 0 {
		st.logger.Infof("No manifest found for release %s", release.Name)
		return nil, nil
	}

	defaultNs := namespace
	if defaultNs == "" {
		defaultNs = "default"
	}

	resources, err := resource.ParseManifest(manifest, defaultNs, st.logger)
	if err != nil {
		return nil, fmt.Errorf("failed to parse release resources from manifest: %w", err)
	}

	if len(resources) == 0 {
		st.logger.Infof("No resources found in manifest for release %s", release.Name)
		return nil, nil
	}

	st.logger.Infof("Found %d resources in manifest for release %s", len(resources), release.Name)

	result := make([]*resource.Resource, len(resources))
	for i := range resources {
		result[i] = &resources[i]
	}

	return result, nil
}

func (st *HelmState) getReleaseManifest(release *ReleaseSpec, helm helmexec.Interface) ([]byte, string, error) {
	var tempDir string
	var err error

	if st.tempDir != nil {
		tempDir, err = st.tempDir("", "helmfile-template-")
	} else {
		tempDir, err = os.MkdirTemp("", "helmfile-template-")
	}

	if err != nil {
		return nil, "", fmt.Errorf("failed to create temp directory: %w", err)
	}
	defer func() {
		if err := os.RemoveAll(tempDir); err != nil {
			st.logger.Warnf("Failed to remove temp directory %s: %v", tempDir, err)
		}
	}()

	releaseCopy := *release
	st.ApplyOverrides(&releaseCopy)

	flags, files, err := st.flagsForTemplate(helm, &releaseCopy, 0, &TemplateOpts{})
	if err != nil {
		return nil, "", fmt.Errorf("failed to generate template flags: %w", err)
	}
	defer st.removeFiles(files)

	flags = append(flags, "--output-dir", tempDir)

	if err := helm.TemplateRelease(releaseCopy.Name, releaseCopy.ChartPathOrName(), flags...); err != nil {
		return nil, "", fmt.Errorf("failed to run helm template: %w", err)
	}

	var manifest []byte

	err = filepath.Walk(tempDir, func(path string, info os.FileInfo, err error) error {
		if err != nil {
			return err
		}

		if info.IsDir() {
			return nil
		}

		if !strings.HasSuffix(info.Name(), ".yaml") && !strings.HasSuffix(info.Name(), ".yml") {
			return nil
		}

		content, err := os.ReadFile(path)
		if err != nil {
			return fmt.Errorf("failed to read file %s: %w", path, err)
		}

		if len(manifest) > 0 {
			manifest = append(manifest, []byte("\n---\n")...)
		}
		manifest = append(manifest, content...)

		return nil
	})

	if err != nil {
		return nil, "", fmt.Errorf("failed to walk template output directory: %w", err)
	}

	return manifest, releaseCopy.Namespace, nil
}

func convertTrackResources(resources []TrackResourceSpec) []resource.Resource {
	if len(resources) == 0 {
		return nil
	}
	result := make([]resource.Resource, len(resources))
	for i, r := range resources {
		result[i] = resource.Resource{
			Kind:      r.Kind,
			Name:      r.Name,
			Namespace: r.Namespace,
		}
	}
	return result
}
