urldecode filenames

dirurldecode.go

package main

import (
	"flag"
	"fmt"
	"io/ioutil"
	"log"
	"net/url"
	"os"
	"path/filepath"
	"strings"

	"github.com/mgutz/ansi"
)

func main() {
	perform := flag.Bool("p", false, "perform the rename manipuations")
	force := flag.Bool("f", false, "overwrite existing files and create non-existent directories")
	showAll := flag.Bool("a", false, "show all files")

	flag.Usage = func() {
		fmt.Println("This utility helps to batch rename files from urlencoded to normal at current directory")
		fmt.Fprintf(os.Stderr, "Usage: %s [options]\n", os.Args[0])
		flag.PrintDefaults()
	}
	flag.Parse()

	fis, err := ioutil.ReadDir(".")
	checkErr(err)

	for _, fi := range fis {
		if fi.IsDir() {
			continue
		}

		// convert filename to normal
		origName := fi.Name()
		escapedName, err := url.QueryUnescape(origName)
		checkErr(err)

		if escapedName == origName {
			if *showAll {
				fmt.Printf("[%s]%s => %s\n", ansi.Color("ignored", "gray+b"), origName, escapedName)
			}
		} else {
			if *perform { // check conditions and perform the rename manipuations
				performOp(origName, escapedName, *force)
			} else { // dryrun only without perform the reanme manipuations
				fmt.Printf("[%s]%s => %s\n", ansi.Color("to be converted", "yellow+b"), origName, escapedName)
			}
		}

	}
}

func checkErr(err error) {
	if err != nil {
		log.Fatal(ansi.Color(err.Error(), "red+b"))
	}
}

func performOp(orig string, target string, force bool) {

	existed := fileExist(target)

	// check if target file is existed
	if existed {
		if !force {
			fmt.Printf("[%s]%s => %s\n", ansi.Color("skipped", "cyan+b"), orig, target)
			return
		}
	}

	// check if target file contains non-existent directories
	hasDir := strings.ContainsRune(target, os.PathSeparator)
	if hasDir {
		baseDir := filepath.Dir(target)

		if !fileExist(baseDir) {
			if !force {
				fmt.Printf("[%s]%s => %s\n", ansi.Color("skipped", "cyan+b"), orig, target)
				return
			}

			err := os.MkdirAll(baseDir, 0766)
			checkErr(err)
		}
	}

	performRename(orig, target)
}

func fileExist(name string) bool {
	_, err := os.Stat(name)
	return err == nil
}

func performRename(orig string, target string) {
	fmt.Printf("[%s]%s => %s\n", ansi.Color("renamed", "green+b"), orig, target)
	err := os.Rename(orig, target)
	checkErr(err)
}