package main

import (
	"crypto/sha256"
	"fmt"
	"os"
	"os/signal"
	"time"
)

const b58alphabet = "123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz"

func b58encode(b []byte) string {
	zeroes := 0
	for zeroes < len(b) && b[zeroes] == 0 {
		zeroes++
	}
	var x [64]byte
	buf := x[:0]
	for _, v := range b {
		carry := int(v)
		for i := len(buf) - 1; i >= 0; i-- {
			carry += int(buf[i]) * 256
			buf[i] = byte(carry % 58)
			carry /= 58
		}
		for carry > 0 {
			buf = append([]byte{byte(carry % 58)}, buf...)
			carry /= 58
		}
	}
	out := make([]byte, zeroes)
	for _, v := range buf {
		out = append(out, b58alphabet[int(v)])
	}
	for i := 0; i < zeroes; i++ {
		out[i] = '1'
	}
	return string(out)
}

func b58checkEncode(version byte, payload []byte) string {
	b := make([]byte, 1+len(payload)+4)
	b[0] = version
	copy(b[1:], payload)
	h := sha256.Sum256(b[:1+len(payload)])
	h2 := sha256.Sum256(h[:])
	copy(b[1+len(payload):], h2[:4])
	return b58encode(b)
}

func main() {
	h := sha256.Sum256([]byte(fmt.Sprint(time.Now().UnixNano())))

	done := make(chan os.Signal, 1)
	signal.Notify(done, os.Interrupt)

	go func() {
		for {
			select {
			case <-done:
				return
			default:
				h = sha256.Sum256(h[:])
			}
		}
	}()

	<-done

	fmt.Println("\n\nhex:", fmt.Sprintf("%x", h[:]))

	wif := b58checkEncode(0x80, h[:])
	fmt.Println("WIF (uncompressed):", wif)

	compressedPayload := make([]byte, 33)
	copy(compressedPayload, h[:])
	compressedPayload[32] = 0x01
	wifCompressed := b58checkEncode(0x80, compressedPayload)
	fmt.Println("WIF (compressed):  ", wifCompressed)
}