weekadd

cmd/weekadd/weekadd.go

@@ -0,0 +1,50 @@
+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)
+}