// Copyright 2019 The Fuchsia 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 simulator

import (
	"crypto/rand"
	"encoding/hex"
	"os"
	"path/filepath"
	"testing"

	"go.fuchsia.dev/fuchsia/tools/emulator"
)

// TestSerial verifies that the serial shell is enabled for recovery-eng.
func TestSerialShellEnabled(t *testing.T) {
	exPath := execDir(t)
	distro, err := emulator.UnpackFrom(filepath.Join(exPath, "test_data"), emulator.DistributionParams{Emulator: emulator.Qemu})
	if err != nil {
		t.Fatal(err)
	}
	defer func() {
		if err := distro.Delete(); err != nil {
			t.Error(err)
		}
	}()

	arch, err := distro.TargetCPU()
	if err != nil {
		t.Fatal(err)
	}

	device := emulator.DefaultVirtualDevice(string(arch))
	device.Initrd = "recovery-eng"
	device.KernelArgs = append(device.KernelArgs, "devmgr.log-to-debuglog")
	i, err := distro.Create(device)
	if err != nil {
		t.Fatal(err)
	}

	if err = i.Start(); err != nil {
		t.Fatal(err)
	}
	defer func() {
		if err := i.Kill(); err != nil {
			t.Error(err)
		}
	}()

	if err = i.WaitForLogMessage("Launching /boot/bin/sh (sh:console)"); err != nil {
		t.Fatal(err)
	}
	tokenFromSerial := randomTokenAsString(t)
	if err = i.RunCommand("echo '" + tokenFromSerial + "'"); err != nil {
		t.Fatal(err)
	}
	if err = i.WaitForLogMessage(tokenFromSerial); err != nil {
		t.Fatal(err)
	}
}

func execDir(t *testing.T) string {
	ex, err := os.Executable()
	if err != nil {
		t.Fatal(err)
	}
	return filepath.Dir(ex)
}

func randomTokenAsString(t *testing.T) string {
	b := [32]byte{}
	if _, err := rand.Read(b[:]); err != nil {
		t.Fatal(err)
	}
	return hex.EncodeToString(b[:])
}