package main

import (
	ww "git.web.rug.nl/p209327/nlnieuws/internal/week"

	e "codeberg.org/pebbe/errors"

	"fmt"
	"io"
	"os"
	"strconv"
	"strings"
)

var (
	x = e.ExitErr
)

func syntax(w io.Writer) {
	fmt.Fprintf(w, `
Usage: %s yyyy.ww n

`, os.Args[0])
}

func main() {
	if len(os.Args) != 3 {
		syntax(os.Stdout)
		return
	}

	aa := strings.Split(os.Args[1], ".")
	if len(aa) != 2 {
		syntax(os.Stderr)
		return
	}
	year, err := strconv.Atoi(aa[0])
	x(err)
	week, err := strconv.Atoi(aa[1])
	x(err)

	n, err := strconv.Atoi(os.Args[2])
	x(err)

	t, err := ww.WeekDate(year, week)
	x(err)

	y, w := t.AddDate(0, 0, n*7).ISOWeek()
	fmt.Printf("%d.%02d\n", y, w)
}