package main

import (
	"encoding/json"
	"errors"
	"net/http"

	"github.com/julienschmidt/httprouter"
)

var AuthFunc = checkAuth

func init() {
	router.GET("/api/auth", apiAuthHandler(validateAuthToken))
	router.POST("/api/auth", apiHandler(func(ps httprouter.Params, body []byte) (interface{}, error) {
		return AuthFunc(ps, body)
	}))
}

func validateAuthToken(s Student, _ httprouter.Params, _ []byte) (interface{}, error) {
	return s, nil
}

type loginForm struct {
	Username string
	Password string
}

func dummyAuth(_ httprouter.Params, body []byte) (interface{}, error) {
	var lf loginForm
	if err := json.Unmarshal(body, &lf); err != nil {
		return nil, err
	}

	var std Student
	var err error
	if !studentExists(lf.Username) {
		if std, err = NewStudent(lf.Username); err != nil {
			return nil, err
		}
	} else if std, err = getStudentByLogin(lf.Username); err != nil {
		return nil, err
	}

	session, err := std.NewSession()
	if err != nil {
		return nil, err
	}

	res := map[string]interface{}{}
	res["status"] = "OK"
	res["id_session"] = session.Id

	return res, nil
}

func checkAuth(_ httprouter.Params, body []byte) (interface{}, error) {
	var lf loginForm
	if err := json.Unmarshal(body, &lf); err != nil {
		return nil, err
	}

	if r, err := http.NewRequest("GET", "https://fic.srs.epita.fr/2020/", nil); err != nil {
		return nil, err
	} else {
		r.SetBasicAuth(lf.Username, lf.Password)

		if resp, err := http.DefaultClient.Do(r); err != nil {
			return nil, err
		} else {
			defer resp.Body.Close()

			if resp.StatusCode == http.StatusOK {
				return dummyAuth(nil, body)
			} else {
				return nil, errors.New(`{"status": "Invalid username or password"}`)
			}
		}
	}
}