package main

import (
	"bytes"
	"fmt"
	"os"
	"strings"
	"strconv"
)

func bitStringToBytes(s string) ([]byte, error) {
	size := 8
	ss := make([]string, 0, len(s)/size+1)
	for len(s) > 0 {
		if len(s) < size {
			size = len(s)
		}
		ss, s = append(ss, s[:size]), s[size:]
	}
	var buf bytes.Buffer
	for _, bs := range ss {
		n, err := strconv.ParseUint(bs, 2, 8)
		if err != nil {
			return nil, err
		}
		buf.WriteByte(byte(n))
	}
	return buf.Bytes(), nil
}

func bytesToBitString(b []byte) string {
	s := fmt.Sprintf("%08b", b)
	return strings.ReplaceAll(s[1:len(s)-1], " ", "")
}

func main() {
	s := "Hello, playground"
	fmt.Printf("\nstring\n%s\n%b\n\n", s, []byte(s))
	
	bitstr := bytesToBitString([]byte(s))
	fmt.Printf("\nbitstring\n%s\n\n", bitstr)
	
	b, err := bitStringToBytes(bitstr)
	if err != nil {
		fmt.Println(err)
		os.Exit(1)
	}
	fmt.Println(string(b))
}