package model

import (
	"slices"
	"testing"
)

func TestNameLess(t *testing.T) {
	want := []string{
		"10.0.10.in-addr.arpa.",
		"1.10.0.10.in-addr.arpa.",
		"02.10.0.10.in-addr.arpa.",
		"2.10.0.10.in-addr.arpa.",
		"10.10.0.10.in-addr.arpa.",
		"101.10.0.10.in-addr.arpa.",
		"x.101.10.0.10.in-addr.arpa.",
		"254.10.0.10.in-addr.arpa.",
		"a.10.0.10.in-addr.arpa.",
	}
	got := slices.Clone(want)
	slices.Reverse(got)
	slices.SortFunc(got, func(a, b string) int {
		if NameLess(a, b) {
			return -1
		}
		if NameLess(b, a) {
			return 1
		}
		return 0
	})
	if !slices.Equal(got, want) {
		t.Fatalf("got %v\nwant %v", got, want)
	}

	// Non-numeric labels keep canonical (byte) order.
	if !NameLess("host10.example.", "host2.example.") {
		t.Error("host10 should sort before host2")
	}
	if !NameLess("example.", "www.example.") {
		t.Error("parent should sort before child")
	}
}