package vulnerabilities

import (
	"compress/gzip"
	"context"
	"io/ioutil"
	"net/http"
	"net/http/httptest"
	"os"
	"path/filepath"
	"strings"
	"testing"
	"time"

	"github.com/facebookincubator/nvdtools/cpedict"
	"github.com/fleetdm/fleet/v4/pkg/fleethttp"
	"github.com/fleetdm/fleet/v4/pkg/nettest"
	"github.com/fleetdm/fleet/v4/server/fleet"
	"github.com/fleetdm/fleet/v4/server/mock"
	kitlog "github.com/go-kit/kit/log"
	"github.com/stretchr/testify/assert"
	"github.com/stretchr/testify/require"
)

func TestCPEFromSoftware(t *testing.T) {
	tempDir := t.TempDir()

	items, err := cpedict.Decode(strings.NewReader(XmlCPETestDict))
	require.NoError(t, err)

	dbPath := filepath.Join(tempDir, "cpe.sqlite")

	err = GenerateCPEDB(dbPath, items)
	require.NoError(t, err)

	db, err := sqliteDB(dbPath)
	require.NoError(t, err)

	// checking an non existent version returns empty
	cpe, err := CPEFromSoftware(db, &fleet.Software{Name: "Vendor Product-1.app", Version: "2.3.4", Source: "apps"})
	require.NoError(t, err)
	require.Equal(t, "", cpe)

	// checking a version that exists works
	cpe, err = CPEFromSoftware(db, &fleet.Software{Name: "Vendor Product-1.app", Version: "1.2.3", Source: "apps"})
	require.NoError(t, err)
	require.Equal(t, "cpe:2.3:a:vendor:product-1:1.2.3:*:*:*:*:macos:*:*", cpe)

	// follows many deprecations
	cpe, err = CPEFromSoftware(db, &fleet.Software{Name: "Vendor2 Product2.app", Version: "0.3", Source: "apps"})
	require.NoError(t, err)
	require.Equal(t, "cpe:2.3:a:vendor2:product4:999:*:*:*:*:macos:*:*", cpe)
}

func TestSyncCPEDatabase(t *testing.T) {
	nettest.Run(t)

	client := fleethttp.NewClient()

	tempDir := t.TempDir()

	// first time, db doesn't exist, so it downloads
	err := DownloadCPEDatabase(tempDir, client)
	require.NoError(t, err)

	dbPath := filepath.Join(tempDir, "cpe.sqlite")
	db, err := sqliteDB(dbPath)
	require.NoError(t, err)

	// and this works afterwards
	software := &fleet.Software{Name: "1Password.app", Version: "7.2.3", Source: "apps"}
	cpe, err := CPEFromSoftware(db, software)
	require.NoError(t, err)
	require.Equal(t, "cpe:2.3:a:1password:1password:7.2.3:beta0:*:*:*:macos:*:*", cpe)

	npmCPE, err := CPEFromSoftware(db, &fleet.Software{Name: "Adaltas Mixme 0.4.0 for Node.js", Version: "0.4.0", Source: "npm_packages"})
	require.NoError(t, err)
	assert.Equal(t, "cpe:2.3:a:adaltas:mixme:0.4.0:*:*:*:*:node.js:*:*", npmCPE)

	windowsCPE, err := CPEFromSoftware(db, &fleet.Software{Name: "HP Storage Data Protector 8.0 for Windows 8", Version: "8.0", Source: "programs"})
	require.NoError(t, err)
	assert.Equal(t, "cpe:2.3:a:hp:storage_data_protector:8.0:-:*:*:*:windows_7:*:*", windowsCPE)

	// but now we truncate to make sure searching for cpe fails
	err = os.Truncate(dbPath, 0)
	require.NoError(t, err)
	_, err = CPEFromSoftware(db, software)
	require.Error(t, err)

	// and we make the db older than the release
	newTime := time.Date(2000, 1, 1, 1, 1, 1, 1, time.UTC)
	err = os.Chtimes(dbPath, newTime, newTime)
	require.NoError(t, err)

	// then it will download
	err = DownloadCPEDatabase(tempDir, client)
	require.NoError(t, err)

	// let's register the mtime for the db
	stat, err := os.Stat(dbPath)
	require.NoError(t, err)
	mtime := stat.ModTime()

	db.Close()
	db, err = sqliteDB(dbPath)
	require.NoError(t, err)
	defer db.Close()

	cpe, err = CPEFromSoftware(db, software)
	require.NoError(t, err)
	require.Equal(t, "cpe:2.3:a:1password:1password:7.2.3:beta0:*:*:*:macos:*:*", cpe)

	// let some time pass
	time.Sleep(2 * time.Second)

	// let's check it doesn't download because it's new enough
	err = DownloadCPEDatabase(tempDir, client)
	require.NoError(t, err)
	stat, err = os.Stat(dbPath)
	require.NoError(t, err)
	require.Equal(t, mtime, stat.ModTime())
}

type fakeSoftwareIterator struct {
	index     int
	softwares []*fleet.Software
	closed    bool
}

func (f *fakeSoftwareIterator) Next() bool {
	return f.index < len(f.softwares)
}

func (f *fakeSoftwareIterator) Value() (*fleet.Software, error) {
	s := f.softwares[f.index]
	f.index++
	return s, nil
}

func (f *fakeSoftwareIterator) Err() error   { return nil }
func (f *fakeSoftwareIterator) Close() error { f.closed = true; return nil }

func TestTranslateSoftwareToCPE(t *testing.T) {
	nettest.Run(t)

	tempDir := t.TempDir()

	ds := new(mock.Store)

	var cpes []string

	ds.AddCPEForSoftwareFunc = func(ctx context.Context, software fleet.Software, cpe string) error {
		cpes = append(cpes, cpe)
		return nil
	}

	iterator := &fakeSoftwareIterator{
		softwares: []*fleet.Software{
			{
				ID:      1,
				Name:    "Product",
				Version: "1.2.3",
				Source:  "apps",
			},
			{
				ID:      2,
				Name:    "Product2",
				Version: "0.3",
				Source:  "apps",
			},
		},
	}

	ds.AllSoftwareWithoutCPEIteratorFunc = func(ctx context.Context, excludedPlatforms []string) (fleet.SoftwareIterator, error) {
		return iterator, nil
	}

	items, err := cpedict.Decode(strings.NewReader(XmlCPETestDict))
	require.NoError(t, err)

	dbPath := filepath.Join(tempDir, "cpe.sqlite")
	err = GenerateCPEDB(dbPath, items)
	require.NoError(t, err)

	err = TranslateSoftwareToCPE(context.Background(), ds, tempDir, kitlog.NewNopLogger())
	require.NoError(t, err)
	assert.Equal(t, []string{
		"cpe:2.3:a:vendor:product-1:1.2.3:*:*:*:*:macos:*:*",
		"cpe:2.3:a:vendor2:product4:999:*:*:*:*:macos:*:*",
	}, cpes)
	assert.True(t, iterator.closed)
}

func TestSyncsCPEFromURL(t *testing.T) {
	ts := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		zw := gzip.NewWriter(w)

		_, err := zw.Write([]byte("Hello world!"))
		require.NoError(t, err)
		err = zw.Close()
		require.NoError(t, err)
	}))
	defer ts.Close()

	client := fleethttp.NewClient()
	tempDir := t.TempDir()
	err := DownloadCPEDatabase(tempDir, client, WithCPEURL(ts.URL+"/hello-world.gz"))
	require.NoError(t, err)

	dbPath := filepath.Join(tempDir, "cpe.sqlite")
	stored, err := ioutil.ReadFile(dbPath)
	require.NoError(t, err)
	assert.Equal(t, "Hello world!", string(stored))
}