// Copyright 2020 The Chromium OS Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

package wifi

import (
	"context"
	"time"

	"chromiumos/tast/ctxutil"
	"chromiumos/tast/errors"
	"chromiumos/tast/remote/wificell"
	"chromiumos/tast/services/cros/wifi"
	"chromiumos/tast/testing"
	"chromiumos/tast/timing"
)

func init() {
	testing.AddTest(&testing.Test{
		Func: DisconnectClearsIP,
		Desc: "Check that the DUT removes the IP after disconnecting from a WiFi network",
		Contacts: []string{
			"chromeos-wifi-champs@google.com", // WiFi oncall rotation; or http://b/new?component=893827
		},
		Attr:        []string{"group:wificell", "wificell_func"},
		ServiceDeps: []string{wificell.TFServiceName},
		Fixture:     "wificellFixt",
	})
}

func DisconnectClearsIP(ctx context.Context, s *testing.State) {
	tf := s.FixtValue().(*wificell.TestFixture)

	ap, err := tf.DefaultOpenNetworkAP(ctx)
	if err != nil {
		s.Fatal("Failed to configure the AP: ", err)
	}
	defer func(ctx context.Context) {
		if err := tf.DeconfigAP(ctx, ap); err != nil {
			s.Error("Failed to deconfig the AP: ", err)
		}
	}(ctx)
	ctx, cancel := tf.ReserveForDeconfigAP(ctx, ap)
	defer cancel()
	s.Log("AP setup done")

	if _, err := tf.ConnectWifiAP(ctx, ap); err != nil {
		s.Fatal("DUT: failed to connect to WiFi: ", err)
	}
	defer func(ctx context.Context) {
		if _, err := tf.WifiClient().DeleteEntriesForSSID(ctx, &wifi.DeleteEntriesForSSIDRequest{Ssid: []byte(ap.Config().SSID)}); err != nil {
			s.Errorf("Failed to remove entries for ssid=%s, err: %v", ap.Config().SSID, err)
		}
	}(ctx)
	ctx, cancel = ctxutil.Shorten(ctx, 2*time.Second)
	defer cancel()
	s.Log("Connected")

	if err := tf.PingFromDUT(ctx, ap.ServerIP().String()); err != nil {
		s.Fatal("Failed to ping from the DUT: ", err)
	}

	addr, err := tf.ClientIPv4Addrs(ctx)
	if err != nil {
		s.Fatal("DUT: failed to get the IP address: ", err)
	}

	if len(addr) == 0 {
		s.Fatal("DUT: expect an IPv4 address")
	}

	s.Logf("Connected with IP address: %s. Disconnecting WiFi", addr)

	if err := tf.DisconnectWifi(ctx); err != nil {
		s.Fatal("DUT: failed to disconnect WiFi: ", err)
	}

	// Wait for IP to be cleared.
	s.Log("Disconnected. Wait for the IP address to be cleared")
	ctx, st := timing.Start(ctx, "waitIPGone")
	defer st.End()
	if err := testing.Poll(ctx, func(ctx context.Context) error {
		addr, err := tf.ClientIPv4Addrs(ctx)
		if err != nil {
			s.Fatal("DUT: failed to get the IP address: ", err)
		}
		if len(addr) != 0 {
			return errors.Errorf("DUT: expect no IPv4 address, got: %s", addr)
		}
		return nil
	}, &testing.PollOptions{Timeout: 10 * time.Second, Interval: 200 * time.Millisecond}); err != nil {
		s.Fatal("Failed to clear the IP after WiFi disconnected: ", err)
	}
}