package servicelib

import (
	"net"
	"os"
	"path/filepath"
	"strings"
)

func IsAddrInUse(network, addr string) bool {
	ln, err := net.Listen(network, addr)
	if err != nil {
		return true
	}
	_ = ln.Close()
	return false
}

func WriteVersionFile(dir, version string) error {
	file := filepath.Join(dir, "version.txt")
	tmp := file + ".tmp"

	if err := os.MkdirAll(dir, 0755); err != nil {
		return err
	}

	if err := os.WriteFile(tmp, []byte(version+"\n"), 0644); err != nil {
		return err
	}

	return os.Rename(tmp, file)
}

func ReadVersionFile(dir string) (string, error) {
	file := filepath.Join(dir, "version.txt")
	data, err := os.ReadFile(file)
	if err != nil {
		return "", err
	}
	return strings.TrimSpace(string(data)), nil
}