package views

import (
	"fmt"
	"html/template"
	"io/fs"
	"log"
	"net/http"
	"os"
	"strings"

	"github.com/gorilla/csrf"
)

type Template struct {
	htmlTpl *template.Template
}

func (t Template) Execute(w http.ResponseWriter, r *http.Request, data interface{}) {
	tpl, err := t.htmlTpl.Clone()
	if err != nil {
		log.Printf("Template Clone Error: %v", err)
		http.Error(w, "Internal Server Error", http.StatusInternalServerError)
		return
	}

	tpl = tpl.Funcs(template.FuncMap{
		"csrfField": func() template.HTML { return csrf.TemplateField(r) },
	})

	w.Header().Set("Content-Type", "text/html; charset=utf8")
	err = tpl.Execute(w, data)
	if err != nil {
		log.Printf("Error executing template: %v", err)
		http.Error(w, "Internal Server Error", http.StatusInternalServerError)
		return
	}
}
func (t Template) TestTemplate(data interface{}) error {
	var testWriter strings.Builder
	tpl, err := t.htmlTpl.Clone()
	if err != nil {
		return err
	}
	return tpl.Execute(&testWriter, data)
}

func FromFile(pattern ...string) (Template, error) {
	fs := os.DirFS(".")
	return FromFS(fs, pattern...)
}
func FromFS(fs fs.FS, pattern ...string) (Template, error) {
	tpl := template.New(pattern[0])
	tpl = tpl.Funcs(template.FuncMap{
		"csrfField": func() template.HTML {
			return `<div class="hidden">STUB: PLACEHOLDER</div>`
		},
	})
	tpl, err := tpl.ParseFS(fs, pattern...)
	if err != nil {
		return Template{}, fmt.Errorf("Error parsing template: %v", err)
	}
	return Template{
		htmlTpl: tpl,
	}, nil
}

func Must(t Template, err error) Template {
	if err != nil {
		panic(err)
	}
	return t
}