// Package util provides utility functions for the CLI Proxy API server.// It includes helper functions for logging configuration, file system operations,// and other common utilities used throughout the application.package util import (	"fmt"	"io/fs"	"os"	"path/filepath"	"strings" 	"github.com/router-for-me/CLIProxyAPI/v6/internal/config"	log "github.com/sirupsen/logrus") // SetLogLevel configures the logrus log level based on the configuration.// It sets the log level to DebugLevel if debug mode is enabled, otherwise to InfoLevel.func SetLogLevel(cfg *config.Config) {	currentLevel := log.GetLevel()	var newLevel log.Level	if cfg.Debug {		newLevel = log.DebugLevel	} else {		newLevel = log.InfoLevel	} 	if currentLevel != newLevel {		log.SetLevel(newLevel)		log.Infof("log level changed from %s to %s (debug=%t)", currentLevel, newLevel, cfg.Debug)	}} // ResolveAuthDir normalizes the auth directory path for consistent reuse throughout the app.// It expands a leading tilde (~) to the user's home directory and returns a cleaned path.func ResolveAuthDir(authDir string) (string, error) {	if authDir == "" {		return "", nil	}	if strings.HasPrefix(authDir, "~") {		home, err := os.UserHomeDir()		if err != nil {			return "", fmt.Errorf("resolve auth dir: %w", err)		}		remainder := strings.TrimPrefix(authDir, "~")		remainder = strings.TrimLeft(remainder, "/\\")		if remainder == "" {			return filepath.Clean(home), nil		}		normalized := strings.ReplaceAll(remainder, "\\", "/")		return filepath.Clean(filepath.Join(home, filepath.FromSlash(normalized))), nil	}	return filepath.Clean(authDir), nil} // CountAuthFiles returns the number of JSON auth files located under the provided directory.// The function resolves leading tildes to the user's home directory and performs a case-insensitive// match on the ".json" suffix so that files saved with uppercase extensions are also counted.func CountAuthFiles(authDir string) int {	dir, err := ResolveAuthDir(authDir)	if err != nil {		log.Debugf("countAuthFiles: failed to resolve auth directory: %v", err)		return 0	}	if dir == "" {		return 0	}	count := 0	walkErr := filepath.WalkDir(dir, func(path string, d fs.DirEntry, err error) error {		if err != nil {			log.Debugf("countAuthFiles: error accessing %s: %v", path, err)			return nil		}		if d.IsDir() {			return nil		}		if strings.HasSuffix(strings.ToLower(d.Name()), ".json") {			count++		}		return nil	})	if walkErr != nil {		log.Debugf("countAuthFiles: walk error: %v", walkErr)	}	return count} // WritablePath returns the cleaned WRITABLE_PATH environment variable when it is set.// It accepts both uppercase and lowercase variants for compatibility with existing conventions.func WritablePath() string {	for _, key := range []string{"WRITABLE_PATH", "writable_path"} {		if value, ok := os.LookupEnv(key); ok {			trimmed := strings.TrimSpace(value)			if trimmed != "" {				return filepath.Clean(trimmed)			}		}	}	return ""}