package main

import (
	"fmt"
	"html/template"
	"net/http"
	"strconv"
)

func root(w http.ResponseWriter, req *http.Request) {
	writeTimetablePage(w, req, template.HTML(""))
}

func getByRoom(w http.ResponseWriter, req *http.Request) {
	room, err := strconv.Atoi(req.FormValue("raum"))
	if err != nil || room == 0 {
		root(w, req)
		return
	}
	writeTimetablePage(w, req, printTimetable(getTimetable(getOfficeHoursByRoom(room))))
}

func getByCourse(w http.ResponseWriter, req *http.Request) {
	course, err := strconv.Atoi(req.FormValue("veranstaltung"))
	if err != nil || course == 0 {
		root(w, req)
		return
	}
	writeTimetablePage(w, req, printTimetable(getTimetable(getOfficeHoursByCourse(course))))
}

func writeTimetablePage(w http.ResponseWriter, req *http.Request, timetable template.HTML) {
	room, err := strconv.Atoi(req.FormValue("raum"))
	if err != nil {
		room = 0
	}
	course, err := strconv.Atoi(req.FormValue("veranstaltung"))
	if err != nil {
		course = 0
	}
	data := struct {
		Courses        []Course
		Rooms          []Room
		Timetable      template.HTML
		SelectedRoom   int
		SelectedCourse int
	}{getCourses(), getRooms(), timetable, room, course}
	tmpl, err := template.ParseFiles("templates/index.html")
	if err != nil {
		w.WriteHeader(http.StatusInternalServerError)
		w.Write([]byte(fmt.Sprintf("Template konnte nicht geparst werden : %s", string(err.Error()))))
		return
	}
	err = tmpl.Execute(w, data)
	if err != nil {
		w.Write([]byte(fmt.Sprintf("Template konnte nicht geparst werden : %s", string(err.Error()))))
		return
	}
}

func main() {
	http.HandleFunc("/getByRoom", getByRoom)
	http.HandleFunc("/getByCourse", getByCourse)

	http.HandleFunc("/", root)

	http.ListenAndServe(":8080", nil)
}