feature: edit with editor, processor

README.md

@@ -1,13 +1,15 @@
 # Bulk-Rename files/folders
 
-Simple cli-tool to bulk rename files. Piped from stdin.
+Simple cli-tool to bulk rename files. Piped from stdin, with a processor or simply edit with your editor.
 
 ## Install
 
 Arch: `yay -S bmv-bin`
 
 ## Usage Example
 
+### From Stdin
+
 ```
 donttouchme.txt // will be ignored, no destination.
 somefile.txt 1.txt // will be moved
@@ -16,6 +18,18 @@ moveme.txt 1.txt // error, file '1.txt' already exists
 idontexist.txt bla.txt // error, file doesn't exist
 ```
 
+### From Stdin with processor
+
+```
+ls | bmv sed 's/.txt$/\.md/'`
+```
+
+### From Stdin with editor
+
+```
+ls | bmv -e
+```
+
 ## Tip
 
 You can easily bulk rename files with vim/nvim this way. Simply do f.e. `ls | nvim -` and you'll get a buffer with cwd's content. You can of course also use ":r!ls" inside vim to fill the buffer with the output of the command.

main.go

@@ -3,6 +3,8 @@ package main
 import (
 	"bufio"
 	"errors"
+	"fmt"
+	"io"
 	"log"
 	"os"
 	"os/exec"
@@ -11,10 +13,137 @@ import (
 )
 
 func main() {
-	scanner := bufio.NewScanner(os.Stdin)
+	fi, _ := os.Stdin.Stat()
+
+	if (fi.Mode() & os.ModeCharDevice) == 0 {
+		if len(os.Args) > 1 {
+			processor := os.Args[1]
+
+			if processor == "-e" {
+				withEditor(getFiles())
+
+				return
+			}
+
+			_, err := exec.LookPath(processor)
+			if err != nil {
+				panic(err)
+			}
+
+			withProcessor(os.Args[1:])
+
+			return
+		}
+
+		fromStdin()
+	} else {
+		cmd := exec.Command("ls")
+		out, err := cmd.CombinedOutput()
+		if err != nil {
+			panic(string(out))
+		}
 
+		withEditor(strings.Fields(string(out)))
+	}
+}
+
+func getFiles() []string {
+	files := []string{}
+
+	scanner := bufio.NewScanner(os.Stdin)
 	for scanner.Scan() {
-		paths := strings.Fields(scanner.Text())
+		if scanner.Err() != nil {
+			log.Panic(scanner.Err())
+		}
+
+		files = append(files, scanner.Text())
+	}
+
+	return files
+}
+
+func withEditor(files []string) {
+	editor, ok := os.LookupEnv("EDITOR")
+	if !ok {
+		fmt.Println("env var 'EDITOR' not set.")
+		os.Exit(1)
+	}
+
+	dest, err := os.CreateTemp("", "*")
+	if err != nil {
+		panic(err)
+	}
+
+	_, err = dest.WriteString(strings.Join(files, "\n"))
+	if err != nil {
+		panic(err)
+	}
+
+	cmd := exec.Command(editor, dest.Name())
+	cmd.Stdin = os.Stdin
+	cmd.Stdout = os.Stdout
+
+	err = cmd.Run()
+	if err != nil {
+		panic(err)
+	}
+
+	n, err := os.ReadFile(dest.Name())
+	if err != nil {
+		panic(err)
+	}
+
+	toMove := strings.Fields(string(n))
+
+	if len(toMove) != len(files) {
+		panic(fmt.Sprintf("expected %d files, got %d", len(files), len(toMove)))
+	}
+
+	for k, v := range files {
+		if toMove[k] != v {
+			move(v, toMove[k])
+		}
+	}
+}
+
+func withProcessor(args []string) {
+	files := getFiles()
+
+	cmd := exec.Command(args[0], args[1:]...)
+
+	pipe, err := cmd.StdinPipe()
+	if err != nil {
+		panic(err)
+	}
+
+	go func() {
+		defer pipe.Close()
+		io.WriteString(pipe, strings.Join(files, "\n"))
+	}()
+
+	out, err := cmd.CombinedOutput()
+	if err != nil {
+		panic(string(out))
+	}
+
+	n := strings.Fields(string(out))
+
+	if len(n) != len(files) {
+		panic(fmt.Sprintf("expected %d files, got %d", len(files), len(n)))
+	}
+
+	for k, v := range files {
+		move(v, n[k])
+	}
+}
+
+func fromStdin() {
+	scanner := bufio.NewScanner(os.Stdin)
+
+	files := getFiles()
+
+	for _, v := range files {
+		paths := strings.Fields(v)
 
 		if len(paths) < 2 {
 			log.Printf("skipping: %s", scanner.Text())
@@ -26,29 +155,29 @@ func main() {
 			continue
 		}
 
-		if _, err := os.Stat(paths[1]); !errors.Is(err, os.ErrNotExist) {
-			log.Printf("cant move '%s' to '%s', as it already exists.", paths[0], paths[1])
-			continue
-		}
-
-		destDir := filepath.Dir(paths[1])
+		move(paths[0], paths[1])
+	}
+}
 
-		err := os.MkdirAll(destDir, 0755)
-		if err != nil {
-			log.Println(err)
-			continue
-		}
+func move(src, dest string) {
+	if _, err := os.Stat(dest); !errors.Is(err, os.ErrNotExist) {
+		log.Printf("cant move '%s' to '%s', as it already exists.", src, dest)
+		return
+	}
 
-		cmd := exec.Command("mv", paths[0], paths[1])
-		out, err := cmd.CombinedOutput()
-		if err != nil {
-			log.Println(string(out))
-		}
+	destDir := filepath.Dir(dest)
 
-		log.Printf("moved '%s' to '%s'", paths[0], paths[1])
+	err := os.MkdirAll(destDir, 0755)
+	if err != nil {
+		log.Println(err)
+		return
 	}
 
-	if scanner.Err() != nil {
-		log.Panic(scanner.Err())
+	cmd := exec.Command("mv", src, dest)
+	out, err := cmd.CombinedOutput()
+	if err != nil {
+		log.Println(string(out))
 	}
+
+	log.Printf("moved '%s' to '%s'", src, dest)
 }