// cleanConfigDirectory removes old, unused configuration and index formats, a
// suitable time after they have gone out of fashion.
func cleanConfigDirectory() {
	patterns := map[string]time.Duration{
		"panic-*.log":    7 * 24 * time.Hour,  // keep panic logs for a week
		"audit-*.log":    7 * 24 * time.Hour,  // keep audit logs for a week
		"index":          14 * 24 * time.Hour, // keep old index format for two weeks
		"config.xml.v*":  30 * 24 * time.Hour, // old config versions for a month
		"*.idx.gz":       30 * 24 * time.Hour, // these should for sure no longer exist
		"backup-of-v0.8": 30 * 24 * time.Hour, // these neither
	}

	for pat, dur := range patterns {
		pat = filepath.Join(baseDirs["config"], pat)
		files, err := osutil.Glob(pat)
		if err != nil {
			l.Infoln("Cleaning:", err)
			continue
		}

		for _, file := range files {
			info, err := osutil.Lstat(file)
			if err != nil {
				l.Infoln("Cleaning:", err)
				continue
			}

			if time.Since(info.ModTime()) > dur {
				if err = os.RemoveAll(file); err != nil {
					l.Infoln("Cleaning:", err)
				} else {
					l.Infoln("Cleaned away old file", filepath.Base(file))
				}
			}
		}
	}
}

func (s *apiService) getSystemBrowse(w http.ResponseWriter, r *http.Request) {
	qs := r.URL.Query()
	current := qs.Get("current")
	if current == "" {
		if roots, err := osutil.GetFilesystemRoots(); err == nil {
			sendJSON(w, roots)
		} else {
			http.Error(w, err.Error(), 500)
		}
		return
	}
	search, _ := osutil.ExpandTilde(current)
	pathSeparator := string(os.PathSeparator)
	if strings.HasSuffix(current, pathSeparator) && !strings.HasSuffix(search, pathSeparator) {
		search = search + pathSeparator
	}
	subdirectories, _ := osutil.Glob(search + "*")
	ret := make([]string, 0, len(subdirectories))
	for _, subdirectory := range subdirectories {
		info, err := os.Stat(subdirectory)
		if err == nil && info.IsDir() {
			ret = append(ret, subdirectory+pathSeparator)
		}
	}

	sendJSON(w, ret)
}

func (p *rwFolder) moveForConflict(name string) error {
	if p.maxConflicts == 0 {
		if err := osutil.Remove(name); err != nil && !os.IsNotExist(err) {
			return err
		}
		return nil
	}

	ext := filepath.Ext(name)
	withoutExt := name[:len(name)-len(ext)]
	newName := withoutExt + time.Now().Format(".sync-conflict-20060102-150405") + ext
	err := os.Rename(name, newName)
	if os.IsNotExist(err) {
		// We were supposed to move a file away but it does not exist. Either
		// the user has already moved it away, or the conflict was between a
		// remote modification and a local delete. In either way it does not
		// matter, go ahead as if the move succeeded.
		err = nil
	}
	if p.maxConflicts > -1 {
		matches, gerr := osutil.Glob(withoutExt + ".sync-conflict-????????-??????" + ext)
		if gerr == nil && len(matches) > p.maxConflicts {
			sort.Sort(sort.Reverse(sort.StringSlice(matches)))
			for _, match := range matches[p.maxConflicts:] {
				gerr = osutil.Remove(match)
				if gerr != nil {
					l.Debugln(p, "removing extra conflict", gerr)
				}
			}
		} else if gerr != nil {
			l.Debugln(p, "globbing for conflicts", gerr)
		}
	}
	return err
}

func TestGlob(t *testing.T) {
	testcases := []string{
		`C:\*`,
		`\\?\C:\*`,
		`\\?\C:\Users`,
		`\\?\\\?\C:\Users`,
	}
	for _, tc := range testcases {
		if _, err := osutil.Glob(tc); err != nil {
			t.Fatalf("pattern %s failed: %v", tc, err)
		}
	}
}

func (s *apiService) getSystemBrowse(w http.ResponseWriter, r *http.Request) {
	qs := r.URL.Query()
	current := qs.Get("current")
	search, _ := osutil.ExpandTilde(current)
	pathSeparator := string(os.PathSeparator)
	if strings.HasSuffix(current, pathSeparator) && !strings.HasSuffix(search, pathSeparator) {
		search = search + pathSeparator
	}
	subdirectories, _ := osutil.Glob(search + "*")
	ret := make([]string, 0, 10)
	for _, subdirectory := range subdirectories {
		info, err := os.Stat(subdirectory)
		if err == nil && info.IsDir() {
			ret = append(ret, subdirectory+pathSeparator)
			if len(ret) > 9 {
				break
			}
		}
	}

	sendJSON(w, ret)
}

// rm -rf
func removeAll(dirs ...string) error {
	for _, dir := range dirs {
		files, err := osutil.Glob(dir)
		if err != nil {
			return err
		}
		for _, file := range files {
			// Set any non-writeable files and dirs to writeable. This is necessary for os.RemoveAll to work on Windows.
			filepath.Walk(file, func(path string, info os.FileInfo, err error) error {
				if err != nil {
					return err
				}
				if info.Mode()&0700 != 0700 {
					os.Chmod(path, 0777)
				}
				return nil
			})
			os.RemoveAll(file)
		}
	}
	return nil
}

func (s *apiSvc) getSystemBrowse(w http.ResponseWriter, r *http.Request) {
	w.Header().Set("Content-Type", "application/json; charset=utf-8")
	qs := r.URL.Query()
	current := qs.Get("current")
	search, _ := osutil.ExpandTilde(current)
	pathSeparator := string(os.PathSeparator)
	if strings.HasSuffix(current, pathSeparator) && !strings.HasSuffix(search, pathSeparator) {
		search = search + pathSeparator
	}
	subdirectories, _ := osutil.Glob(search + "*")
	ret := make([]string, 0, 10)
	for _, subdirectory := range subdirectories {
		info, err := os.Stat(subdirectory)
		if err == nil && info.IsDir() {
			ret = append(ret, subdirectory+pathSeparator)
			if len(ret) > 9 {
				break
			}
		}
	}
	json.NewEncoder(w).Encode(ret)
}

func TestCLIReset(t *testing.T) {
	dirs := []string{"h1/index-v0.11.0.db"}

	// Create directories that reset will remove

	for _, dir := range dirs {
		err := os.Mkdir(dir, 0755)
		if err != nil && !os.IsExist(err) {
			t.Fatal(err)
		}
	}

	// Run reset to clean up

	cmd := exec.Command("../bin/syncthing", "-no-browser", "-home", "h1", "-reset")
	cmd.Stdout = os.Stdout
	cmd.Stderr = os.Stdout
	err := cmd.Run()
	if err != nil {
		t.Fatal(err)
	}

	// Verify that they're gone

	for _, dir := range dirs {
		_, err := os.Stat(dir)
		if err == nil {
			t.Errorf("%s still exists", dir)
		}
	}

	// Clean up

	dirs, err = osutil.Glob("*.syncthing-reset-*")
	if err != nil {
		t.Fatal(err)
	}
	removeAll(dirs...)
}

// Archive moves the named file away to a version archive. If this function
// returns nil, the named file does not exist any more (has been archived).
func (v Staggered) Archive(filePath string) error {
	if debug {
		l.Debugln("Waiting for lock on ", v.versionsPath)
	}
	v.mutex.Lock()
	defer v.mutex.Unlock()

	_, err := osutil.Lstat(filePath)
	if os.IsNotExist(err) {
		if debug {
			l.Debugln("not archiving nonexistent file", filePath)
		}
		return nil
	} else if err != nil {
		return err
	}

	if _, err := os.Stat(v.versionsPath); err != nil {
		if os.IsNotExist(err) {
			if debug {
				l.Debugln("creating versions dir", v.versionsPath)
			}
			osutil.MkdirAll(v.versionsPath, 0755)
			osutil.HideFile(v.versionsPath)
		} else {
			return err
		}
	}

	if debug {
		l.Debugln("archiving", filePath)
	}

	file := filepath.Base(filePath)
	inFolderPath, err := filepath.Rel(v.folderPath, filepath.Dir(filePath))
	if err != nil {
		return err
	}

	dir := filepath.Join(v.versionsPath, inFolderPath)
	err = osutil.MkdirAll(dir, 0755)
	if err != nil && !os.IsExist(err) {
		return err
	}

	ver := taggedFilename(file, time.Now().Format(TimeFormat))
	dst := filepath.Join(dir, ver)
	if debug {
		l.Debugln("moving to", dst)
	}
	err = osutil.Rename(filePath, dst)
	if err != nil {
		return err
	}

	// Glob according to the new file~timestamp.ext pattern.
	newVersions, err := osutil.Glob(filepath.Join(dir, taggedFilename(file, TimeGlob)))
	if err != nil {
		l.Warnln("globbing:", err)
		return nil
	}

	// Also according to the old file.ext~timestamp pattern.
	oldVersions, err := osutil.Glob(filepath.Join(dir, file+"~"+TimeGlob))
	if err != nil {
		l.Warnln("globbing:", err)
		return nil
	}

	// Use all the found filenames.
	versions := append(oldVersions, newVersions...)
	v.expire(uniqueSortedStrings(versions))

	return nil
}

func TestConflictsIndexReset(t *testing.T) {
	log.Println("Cleaning...")
	err := removeAll("s1", "s2", "h1/index*", "h2/index*")
	if err != nil {
		t.Fatal(err)
	}

	err = os.Mkdir("s1", 0755)
	if err != nil {
		t.Fatal(err)
	}
	err = os.Mkdir("s2", 0755)
	if err != nil {
		t.Fatal(err)
	}

	// Three files on s1

	err = ioutil.WriteFile("s1/file1", []byte("hello\n"), 0644)
	if err != nil {
		t.Fatal(err)
	}
	err = ioutil.WriteFile("s1/file2", []byte("hello\n"), 0644)
	if err != nil {
		t.Fatal(err)
	}
	err = ioutil.WriteFile("s2/file3", []byte("hello\n"), 0644)
	if err != nil {
		t.Fatal(err)
	}

	// Let them sync

	sender := startInstance(t, 1)
	defer checkedStop(t, sender)
	receiver := startInstance(t, 2)
	defer checkedStop(t, receiver)

	log.Println("Syncing...")

	rc.AwaitSync("default", sender, receiver)

	log.Println("Verifying...")

	// s1 should have three files

	files, err := osutil.Glob("s1/file*")
	if err != nil {
		t.Fatal(err)
	}
	if len(files) != 3 {
		t.Errorf("Expected 3 files in s1 instead of %d", len(files))
	}

	// s2 should have three

	files, err = osutil.Glob("s2/file*")
	if err != nil {
		t.Fatal(err)
	}
	if len(files) != 3 {
		t.Errorf("Expected 3 files in s2 instead of %d", len(files))
	}

	log.Println("Updating...")

	// change s2/file2 a few times, so that it's version counter increases.
	// This will make the file on the cluster look newer than what we have
	// locally after we rest the index, unless we have a fix for that.

	for i := 0; i < 5; i++ {
		err = ioutil.WriteFile("s2/file2", []byte("hello1\n"), 0644)
		if err != nil {
			t.Fatal(err)
		}
		err = receiver.Rescan("default")
		if err != nil {
			t.Fatal(err)
		}
		time.Sleep(time.Second)
	}

	rc.AwaitSync("default", sender, receiver)

	// Now nuke the index

	log.Println("Resetting...")

	checkedStop(t, receiver)
	removeAll("h2/index*")

	// s1/file1 (remote) changes while receiver is down

	err = ioutil.WriteFile("s1/file1", []byte("goodbye\n"), 0644)
	if err != nil {
		t.Fatal(err)
	}

	// s1 must know about it
	err = sender.Rescan("default")
//.........这里部分代码省略.........

//.........这里部分代码省略.........
	err = fd.Close()
	if err != nil {
		t.Fatal(err)
	}

	fd, err = os.OpenFile("s2/testfile.txt", os.O_WRONLY|os.O_APPEND, 0644)
	if err != nil {
		t.Fatal(err)
	}
	_, err = fd.WriteString("text added to s2\n")
	if err != nil {
		t.Fatal(err)
	}
	err = fd.Close()
	if err != nil {
		t.Fatal(err)
	}

	if err := sender.ResumeDevice(receiver.ID()); err != nil {
		t.Fatal(err)
	}

	log.Println("Syncing...")

	if err := sender.RescanDelay("default", 86400); err != nil {
		t.Fatal(err)
	}
	if err := receiver.RescanDelay("default", 86400); err != nil {
		t.Fatal(err)
	}
	rc.AwaitSync("default", sender, receiver)

	// The conflict is expected on the s2 side due to how we calculate which
	// file is the winner (based on device ID)

	files, err := osutil.Glob("s2/*sync-conflict*")
	if err != nil {
		t.Fatal(err)
	}
	if len(files) != 1 {
		t.Errorf("Expected 1 conflicted files instead of %d", len(files))
	}

	log.Println("Introducing a conflict (edit plus delete)...")

	if err := sender.PauseDevice(receiver.ID()); err != nil {
		t.Fatal(err)
	}

	err = os.Remove("s1/testfile.txt")
	if err != nil {
		t.Fatal(err)
	}

	fd, err = os.OpenFile("s2/testfile.txt", os.O_WRONLY|os.O_APPEND, 0644)
	if err != nil {
		t.Fatal(err)
	}
	_, err = fd.WriteString("more text added to s2\n")
	if err != nil {
		t.Fatal(err)
	}
	err = fd.Close()
	if err != nil {
		t.Fatal(err)
	}

	if err := sender.ResumeDevice(receiver.ID()); err != nil {
		t.Fatal(err)
	}

	log.Println("Syncing...")

	if err := sender.RescanDelay("default", 86400); err != nil {
		t.Fatal(err)
	}
	if err := receiver.RescanDelay("default", 86400); err != nil {
		t.Fatal(err)
	}
	rc.AwaitSync("default", sender, receiver)

	// The conflict is resolved to the advantage of the edit over the delete.
	// As such, we get the edited content synced back to s1 where it was
	// removed.

	files, err = osutil.Glob("s2/*sync-conflict*")
	if err != nil {
		t.Fatal(err)
	}
	if len(files) != 1 {
		t.Errorf("Expected 1 conflicted files instead of %d", len(files))
	}
	bs, err := ioutil.ReadFile("s1/testfile.txt")
	if err != nil {
		t.Error("reading file:", err)
	}
	if !bytes.Contains(bs, []byte("more text added to s2")) {
		t.Error("s1/testfile.txt should contain data added in s2")
	}
}

func TestConflictsInitialMerge(t *testing.T) {
	log.Println("Cleaning...")
	err := removeAll("s1", "s2", "h1/index*", "h2/index*")
	if err != nil {
		t.Fatal(err)
	}

	err = os.Mkdir("s1", 0755)
	if err != nil {
		t.Fatal(err)
	}
	err = os.Mkdir("s2", 0755)
	if err != nil {
		t.Fatal(err)
	}

	// File 1 is a conflict

	err = ioutil.WriteFile("s1/file1", []byte("hello\n"), 0644)
	if err != nil {
		t.Fatal(err)
	}

	err = ioutil.WriteFile("s2/file1", []byte("goodbye\n"), 0644)
	if err != nil {
		t.Fatal(err)
	}

	// File 2 exists on s1 only

	err = ioutil.WriteFile("s1/file2", []byte("hello\n"), 0644)
	if err != nil {
		t.Fatal(err)
	}

	// File 3 exists on s2 only

	err = ioutil.WriteFile("s2/file3", []byte("goodbye\n"), 0644)
	if err != nil {
		t.Fatal(err)
	}

	// Let them sync

	sender := startInstance(t, 1)
	defer checkedStop(t, sender)
	receiver := startInstance(t, 2)
	defer checkedStop(t, receiver)

	log.Println("Syncing...")

	rc.AwaitSync("default", sender, receiver)

	checkedStop(t, sender)
	checkedStop(t, receiver)

	log.Println("Verifying...")

	// s1 should have three-four files (there's a conflict from s2 which may or may not have synced yet)

	files, err := osutil.Glob("s1/file*")
	if err != nil {
		t.Fatal(err)
	}
	if len(files) < 3 || len(files) > 4 {
		t.Errorf("Expected 3-4 files in s1 instead of %d", len(files))
	}

	// s2 should have four files (there's a conflict)

	files, err = osutil.Glob("s2/file*")
	if err != nil {
		t.Fatal(err)
	}
	if len(files) != 4 {
		t.Errorf("Expected 4 files in s2 instead of %d", len(files))
	}

	// file1 is in conflict, so there's two versions of that one

	files, err = osutil.Glob("s2/file1*")
	if err != nil {
		t.Fatal(err)
	}
	if len(files) != 2 {
		t.Errorf("Expected 2 'file1' files in s2 instead of %d", len(files))
	}
}

// Archive moves the named file away to a version archive. If this function
// returns nil, the named file does not exist any more (has been archived).
func (v Simple) Archive(filePath string) error {
	fileInfo, err := osutil.Lstat(filePath)
	if os.IsNotExist(err) {
		l.Debugln("not archiving nonexistent file", filePath)
		return nil
	} else if err != nil {
		return err
	}

	versionsDir := filepath.Join(v.folderPath, ".stversions")
	_, err = os.Stat(versionsDir)
	if err != nil {
		if os.IsNotExist(err) {
			l.Debugln("creating versions dir", versionsDir)
			osutil.MkdirAll(versionsDir, 0755)
			osutil.HideFile(versionsDir)
		} else {
			return err
		}
	}

	l.Debugln("archiving", filePath)

	file := filepath.Base(filePath)
	inFolderPath, err := filepath.Rel(v.folderPath, filepath.Dir(filePath))
	if err != nil {
		return err
	}

	dir := filepath.Join(versionsDir, inFolderPath)
	err = osutil.MkdirAll(dir, 0755)
	if err != nil && !os.IsExist(err) {
		return err
	}

	ver := taggedFilename(file, fileInfo.ModTime().Format(TimeFormat))
	dst := filepath.Join(dir, ver)
	l.Debugln("moving to", dst)
	err = osutil.Rename(filePath, dst)
	if err != nil {
		return err
	}

	// Glob according to the new file~timestamp.ext pattern.
	pattern := filepath.Join(dir, taggedFilename(file, TimeGlob))
	newVersions, err := osutil.Glob(pattern)
	if err != nil {
		l.Warnln("globbing:", err, "for", pattern)
		return nil
	}

	// Also according to the old file.ext~timestamp pattern.
	pattern = filepath.Join(dir, file+"~"+TimeGlob)
	oldVersions, err := osutil.Glob(pattern)
	if err != nil {
		l.Warnln("globbing:", err, "for", pattern)
		return nil
	}

	// Use all the found filenames. "~" sorts after "." so all old pattern
	// files will be deleted before any new, which is as it should be.
	versions := uniqueSortedStrings(append(oldVersions, newVersions...))

	if len(versions) > v.keep {
		for _, toRemove := range versions[:len(versions)-v.keep] {
			l.Debugln("cleaning out", toRemove)
			err = os.Remove(toRemove)
			if err != nil {
				l.Warnln("removing old version:", err)
			}
		}
	}

	return nil
}