package controllers

import (
	"fmt"
	"html/template"
	"log"
	"net/http"
	"officeHours/models"
	"os"
)

var funcs = template.FuncMap{
	"DayName": models.DayName,
	"divide":  func(i int, j int) int { return i / j },
}
var baseTemplate = template.Must(template.ParseFiles("templates/base.html")).New("base.html").Funcs(funcs)

// Execute a rendered full HTML page.
//
// If you just want to fill a template snippet, use the RawTemplates object.
//
// Parameters:
//   - name is the name of the template file inside templates/, without .html suffix.
//   - data is passed through to the template
func (b *BaseHandler) serveTemplate(w http.ResponseWriter, name string, data any) {
	full_name := "templates/" + name + ".html"
	// check that template exists
	info, err := os.Stat(full_name)
	if (err != nil && os.IsNotExist(err)) || info.IsDir() {
		errMsg := fmt.Sprintf("Template %s nicht gefunden", full_name)
		log.Println(errMsg)
		w.WriteHeader(http.StatusNotFound)
		w.Write([]byte(errMsg))
		return
	}

	tmpl, err := baseTemplate.ParseFiles(full_name)
	if err != nil {
		errMsg := fmt.Sprintf("Template %s konnte nicht geparst werden : %s", full_name, err.Error())
		log.Println(errMsg)
		w.WriteHeader(http.StatusInternalServerError)
		w.Write([]byte(errMsg))
		return
	}
	// TODO: cache templates in parsed state, but not executed
	err = template.Must(tmpl.Clone()).Execute(w, data)
	if err != nil {
		errMsg := fmt.Sprintf("Template %s konnte nicht ausgeführt werden : %s", full_name, err.Error())
		log.Println(errMsg)
		w.WriteHeader(http.StatusInternalServerError)
		w.Write([]byte(errMsg))
		return
	}
}

// standalone templates that should not be wrapped into the base.html
var RawTemplates, TemplateError = template.New("").Funcs(funcs).ParseFiles(
	"templates/confirmationMail",
	"templates/td.html",
	"templates/officeHourTable.html")