package libmkwebpage

import (
	"bytes"
	"embed"
	"fmt"
	"html/template"
	"io/fs"
	"net/http"
	texttemplate "text/template"
)

type templates struct {
	staticRoot    embed.FS
	dynamicRoot   fs.FS
	errorTemplate string
	bindings      template.FuncMap
}

func (w *Webpage) getTemplateRoot() fs.FS {
	if w.isDynamic() {
		return w.templates.dynamicRoot
	}
	return w.templates.staticRoot
}

func (w *Webpage) NewTemplates(static embed.FS, dynamic fs.FS) *Webpage {
	w.templates = templates{staticRoot: static, dynamicRoot: dynamic, bindings: template.FuncMap{}}
	return w
}
func (w *Webpage) SetErrorTemplate(path string) {
	w.templates.errorTemplate = path
}
func (w *Webpage) Error(writer http.ResponseWriter, code int, err error) {
	writer.WriteHeader(code)
	if w.templates.errorTemplate == "" {
		fmt.Fprintln(writer, err)
	}
}
func (w *Webpage) InternalServerError(writer http.ResponseWriter, err error) {
	w.Error(writer, http.StatusInternalServerError, err)
}
func (w *Webpage) BadRequest(writer http.ResponseWriter, err error) {
	w.Error(writer, http.StatusInternalServerError, err)
}
func (w *Webpage) BindTemplateFunc(name string, fun any) *Webpage {
	w.templates.bindings[name] = fun
	return w
}

func (w *Webpage) RenderTemplate(writer http.ResponseWriter, name string, data any) {
	writer.Header().Set("Content-Type", "text/html; charset=utf-8")
	tmpl, err := fs.ReadFile(w.getTemplateRoot(), "templates/"+name+".tmpl")
	if err != nil {
		panic(err)
	}
	if err := template.Must(template.New("templates/"+name+".tmpl").Funcs(w.templates.bindings).Parse(string(tmpl))).Execute(writer, data); err != nil {
		panic(err)
	}
}
func (w *Webpage) RenderTemplateToString(name string, data any) string {
	buf := bytes.NewBuffer(nil)
	tmpl, err := fs.ReadFile(w.getTemplateRoot(), "templates/"+name+".tmpl")
	if err != nil {
		panic(err)
	}
	if err := template.Must(template.New("templates/"+name+".tmpl").Funcs(w.templates.bindings).Parse(string(tmpl))).Execute(buf, data); err != nil {
		panic(err)
	}
	return buf.String()
}
func (w *Webpage) RenderTemplateToStringUnescaped(name string, data any) string {
	buf := bytes.NewBuffer(nil)
	tmpl, err := fs.ReadFile(w.getTemplateRoot(), "templates/"+name+".tmpl")
	if err != nil {
		panic(err)
	}
	if err := texttemplate.Must(texttemplate.New("templates/"+name+".tmpl").Funcs(w.templates.bindings).Parse(string(tmpl))).Execute(buf, data); err != nil {
		panic(err)
	}
	return buf.String()
}