package main

import (
	"encoding/base32"
	"encoding/base64"
	"encoding/xml"
	"flag"
	"fmt"
	"os"

	"github.com/skip2/go-qrcode"
)

func run() error {
	args := flag.Args()
	if len(args) != 1 {
		return fmt.Errorf("usage: auth <config file>")
	}
	fileBytes, err := os.ReadFile(args[0])
	if err != nil {
		return err
	}
	var config struct {
		AuthKey string `xml:",attr"`
	}
	if err := xml.Unmarshal(fileBytes, &config); err != nil {
		return err
	}
	if config.AuthKey == "" {
		return fmt.Errorf("%s: missing AuthKey", args[0])
	}
	authKey, err := base64.StdEncoding.DecodeString(config.AuthKey)
	if err != nil {
		return err
	}
	qrCode, err := qrcode.New(fmt.Sprintf("otpauth://totp/roseh.moe:rose?secret=%s&issuer=roseh.moe", base32.StdEncoding.WithPadding(base32.NoPadding).EncodeToString(authKey)), qrcode.Medium)
	if err != nil {
		return err
	}
	fmt.Print(qrCode.ToSmallString(false))
	return nil
}

func main() {
	flag.Parse()
	if err := run(); err != nil {
		fmt.Fprintln(os.Stderr, err)
		os.Exit(1)
	}
}