// SPDX-FileCopyrightText: 2023 The Pion community <https://pion.ly>
// SPDX-License-Identifier: MIT

package vnet

import (
	"net"
	"testing"

	"github.com/pion/logging"
	"github.com/stretchr/testify/assert"
)

func TestResolver(t *testing.T) {
	loggerFactory := logging.NewDefaultLoggerFactory()
	log := loggerFactory.NewLogger("test")

	t.Run("Standalone", func(t *testing.T) {
		resolver := newResolver(&resolverConfig{
			LoggerFactory: loggerFactory,
		})

		// should have localhost by default
		name := "localhost"
		ipAddr := "127.0.0.1"
		ip := net.ParseIP(ipAddr)

		resolved, err := resolver.lookUp(name)
		assert.NoError(t, err, "should succeed")
		assert.True(t, resolved.Equal(ip), "should match")

		name = "abc.com"
		ipAddr = demoIP
		ip = net.ParseIP(ipAddr)
		log.Debugf("adding %s %s", name, ipAddr)

		err = resolver.addHost(name, ipAddr)
		assert.NoError(t, err, "should succeed")

		resolved, err = resolver.lookUp(name)
		assert.NoError(t, err, "should succeed")
		assert.True(t, resolved.Equal(ip), "should match")
	})

	t.Run("Cascaded", func(t *testing.T) {
		r0 := newResolver(&resolverConfig{
			LoggerFactory: loggerFactory,
		})
		name0 := "abc.com"
		ipAddr0 := demoIP
		ip0 := net.ParseIP(ipAddr0)
		err := r0.addHost(name0, ipAddr0)
		assert.NoError(t, err, "should succeed")

		r1 := newResolver(&resolverConfig{
			LoggerFactory: loggerFactory,
		})
		name1 := "myserver.local"
		ipAddr1 := "10.1.2.5"
		ip1 := net.ParseIP(ipAddr1)
		err = r1.addHost(name1, ipAddr1)
		assert.NoError(t, err, "should succeed")
		r1.setParent(r0)

		resolved, err := r1.lookUp(name0)
		assert.NoError(t, err, "should succeed")
		assert.True(t, resolved.Equal(ip0), "should match")

		resolved, err = r1.lookUp(name1)
		assert.NoError(t, err, "should succeed")
		assert.True(t, resolved.Equal(ip1), "should match")

		// should fail if the name does not exist
		_, err = r1.lookUp("bad.com")
		assert.NotNil(t, err, "should fail")
	})
}