package main

import (
	"fmt"
	"html/template"
	"io/fs"
	"os"
	"strings"
)
import "embed"
import sprig "github.com/Masterminds/sprig/v3" // This provides most Helm functions
import "github.com/goccy/go-yaml"

// This provides most Helm functions

//go:embed templates/*
var templateFS embed.FS

func NewTemplate() *template.Template {
	tmpl := template.New("")

	// Combine sprig functions with custom functions
	funcMap := template.FuncMap{}

	// Add all sprig functions
	for name, fn := range sprig.FuncMap() {
		funcMap[name] = fn
	}

	// Add any custom functions you want
	customFuncs := template.FuncMap{
		"toYaml": func(v interface{}) string {
			data, err := yaml.Marshal(v)
			if err != nil {
				return ""
			}
			return string(data)
		},
	}

	// Merge custom functions
	for name, fn := range customFuncs {
		funcMap[name] = fn
	}

	// Add the function map to the template
	tmpl = tmpl.Funcs(funcMap)

	return tmpl
}

func showContents(files fs.FS) {
	entries, err := fs.ReadDir(files, ".")
	if err != nil {
		panic(err)
	}
	for _, entry := range entries {
		fmt.Printf("entry %s %s\n", entry.Name(), entry.Type())
		if entry.Type().IsDir() {
			subdir, err := fs.Sub(files, entry.Name())
			if err != nil {
				panic(err)
			}
			showContents(subdir)
		}
	}
}

func loadTemplates() (*template.Template, error) {
	showContents(templateFS)

	// Parse all templates at once from the embedded FS
	tmpl := NewTemplate()

	err := loadTemplatesGlob(tmpl)
	if err != nil {
		return nil, err
	}
	return tmpl, err
}

func loadTemplatesGlob(tmpl *template.Template) error {
	return fs.WalkDir(templateFS, ".", func(path string, d os.DirEntry, err error) error {
		if strings.HasSuffix(path, ".yaml") {
			data, err := fs.ReadFile(templateFS, path)
			if err != nil {
				return err
			}
			fmt.Fprintf(os.Stderr, "Loading template %s\n", path)
			tmpl.New(path).Parse(string(data))
		}
		return nil
	})
}