refactor code for better read

internal/adapters/data/ssh_config_file/backup.go

@@ -0,0 +1,127 @@
+// Copyright 2025.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package ssh_config_file
+
+import (
+	"fmt"
+	"io"
+	"os"
+	"path/filepath"
+	"sort"
+	"strings"
+	"time"
+)
+
+// createBackup creates a timestamped backup of the current config file
+func (r *Repository) createBackup() error {
+	if _, err := r.fileSystem.Stat(r.configPath); os.IsNotExist(err) {
+		return nil
+	} else if err != nil {
+		return fmt.Errorf("failed to check if config file exists: %w", err)
+	}
+
+	timestamp := time.Now().UnixMilli()
+	backupPath := fmt.Sprintf("%s-%d-%s", r.configPath, timestamp, BackupSuffix)
+
+	if err := r.copyFile(r.configPath, backupPath); err != nil {
+		return fmt.Errorf("failed to copy config to backup: %w", err)
+	}
+
+	r.logger.Infof("Created backup: %s", backupPath)
+
+	configDir := filepath.Dir(r.configPath)
+
+	backupFiles, err := r.findBackupFiles(configDir)
+	if err != nil {
+		return err
+	}
+
+	if len(backupFiles) <= MaxBackups {
+		return nil
+	}
+
+	sort.Slice(backupFiles, func(i, j int) bool {
+		return backupFiles[i].ModTime().After(backupFiles[j].ModTime())
+	})
+
+	for i := MaxBackups; i < len(backupFiles); i++ {
+		backupPath := filepath.Join(configDir, backupFiles[i].Name())
+		if err := r.fileSystem.Remove(backupPath); err != nil {
+			r.logger.Warnf("failed to remove old backup %s: %v", backupPath, err)
+			continue
+		}
+		r.logger.Infof("Removed old backup: %s", backupPath)
+	}
+	return nil
+}
+
+// copyFile copies a file from src to dst
+func (r *Repository) copyFile(src, dst string) error {
+	srcFile, err := r.fileSystem.Open(src)
+	if err != nil {
+		return err
+	}
+	defer func() {
+		if cerr := srcFile.Close(); cerr != nil {
+			r.logger.Warnf("failed to close source file %s: %v", src, cerr)
+		}
+	}()
+
+	srcInfo, err := r.fileSystem.Stat(src)
+	if err != nil {
+		return err
+	}
+
+	destFile, err := r.fileSystem.OpenFile(dst, os.O_CREATE|os.O_WRONLY|os.O_TRUNC, srcInfo.Mode())
+	if err != nil {
+		return err
+	}
+	defer func() {
+		if cerr := destFile.Close(); cerr != nil {
+			r.logger.Warnf("failed to close destination file %s: %v", dst, cerr)
+		}
+	}()
+
+	_, err = io.Copy(destFile, srcFile)
+	if err != nil {
+		return err
+	}
+
+	return destFile.Sync()
+}
+
+// findBackupFiles finds all backup files for the given config file
+func (r *Repository) findBackupFiles(dir string) ([]os.FileInfo, error) {
+	entries, err := r.fileSystem.ReadDir(dir)
+	if err != nil {
+		return nil, err
+	}
+
+	var backupFiles []os.FileInfo
+
+	for _, entry := range entries {
+		name := entry.Name()
+		if strings.HasSuffix(name, BackupSuffix) {
+			info, err := entry.Info()
+			if err != nil {
+				r.logger.Warnf("failed to get info for backup file %s: %v", name, err)
+				continue
+			}
+			backupFiles = append(backupFiles, info)
+		}
+	}
+
+	return backupFiles, nil
+}