package main

import (
	"io/ioutil"
	"os"
	"os/exec"
	"strings"
)

func doEditor() (string, error) {
	// Create a temporary file
	tmpfile, err := ioutil.TempFile("", "regex-*.txt")
	if err != nil {
		return "", err
	}
	tmpPath := tmpfile.Name()
	// Defer removal in case of error, but we might move it
	defer os.Remove(tmpPath)
	tmpfile.Close()

	// Get the user's editor
	editor := os.Getenv("EDITOR")
	if editor == "" {
		editor = "vim" // default to vim
	}

	// Run the editor
	cmd := exec.Command(editor, tmpPath)
	cmd.Stdin = os.Stdin
	cmd.Stdout = os.Stdout
	cmd.Stderr = os.Stderr

	if err := cmd.Run(); err != nil {
		return "", err
	}

	// Read the file content
	content, err := ioutil.ReadFile(tmpPath)
	if err != nil {
		return "", err
	}

	// Check if the file is not empty after trimming space
	if strings.TrimSpace(string(content)) != "" {
		// Move the file
		if err := os.Rename(tmpPath, "/tmp/regex.txt"); err != nil {
			return "", err
		}
		return "/tmp/regex.txt", nil
	}

	return "", nil
}