Translated original python work to golang

hexdec.go

@@ -0,0 +1,187 @@
+package main
+
+import (
+	"bufio"
+	"fmt"
+	"log"
+	"math/rand"
+	"os"
+	"os/signal"
+	"strconv"
+	"strings"
+	"syscall"
+	"time"
+)
+
+type boolgen struct {
+	src       rand.Source
+	cache     int64
+	remaining int
+}
+
+var defaultUpperLimit = 0x100
+var dec, hex, mix = "d2x", "x2d", "both"
+var averageTime int64
+var iterations int64
+var userSucceeded bool
+var responseTime int64
+
+func welcome() (int, string) {
+	welcomeBanner := `
+	__________
+	| ________ |
+	||12345678||
+	|''''''''''|
+	|[M|#|C][-]| HexDec - Become a Hexa(decimal) Pro!
+	|[7|8|9][+]| Author: Ophir Harpaz (@ophirharpaz)
+	|[4|5|6][x]| ascii art by hjw
+	|[1|2|3][%]| 
+	|[.|O|:][=]| Translated to GoLang by Quentin Rhoads-Herrera (@paragonsec)
+	|==========|
+
+	Set the game properties using:
+	- the maximal number that will show up;
+	- the game mode (d2x for decimal to hexa, x2d for the opposite direction, or both)
+	`
+	fmt.Println(welcomeBanner)
+
+	//Taking user input for the max number
+	var maxNumber int
+	fmt.Printf("Choose a maximal number [default is %d]: ", defaultUpperLimit)
+	reader := bufio.NewReader(os.Stdin)
+	input, err := reader.ReadString('\n')
+	if err != nil {
+		log.Fatal(err)
+	}
+	input = strings.TrimSpace(input)
+	convNum, err := strconv.Atoi(input)
+	if err != nil {
+		log.Fatal(err)
+	}
+	if convNum == 0 {
+		maxNumber = defaultUpperLimit
+	} else if convNum > 256 {
+		fmt.Println("Number can't be greater than 256! Setting it to 256 for you :)")
+		maxNumber = defaultUpperLimit
+	} else {
+		maxNumber = convNum
+	}
+
+	//Taking user input for game mode
+	var gameMode string
+	fmt.Printf("Game mode (x2d, d2x, both) [x2d]: ")
+	input, err = reader.ReadString('\n')
+	if err != nil {
+		log.Fatal(err)
+	}
+	input = strings.TrimSpace(input)
+	if input == "" {
+		gameMode = "x2d"
+	} else {
+		gameMode = input
+	}
+	return maxNumber, gameMode
+}
+
+func (b *boolgen) Bool() bool {
+	if b.remaining == 0 {
+		b.cache, b.remaining = b.src.Int63(), 63
+	}
+
+	result := b.cache&0x01 == 1
+	b.cache >>= 1
+	b.remaining--
+
+	return result
+}
+
+func new() *boolgen {
+	return &boolgen{src: rand.NewSource(time.Now().UnixNano())}
+}
+
+func play(maxNumber int, gameMode string) {
+
+	fmt.Println("To stop the game use CTRL+C")
+	signalHandler()
+
+	for true {
+		switch {
+		case mix == gameMode:
+			r := new()
+			r.Bool()
+			userSucceeded, responseTime = playIterations(maxNumber, r.Bool())
+		case dec == gameMode:
+			userSucceeded, responseTime = playIterations(maxNumber, false)
+		case hex == gameMode:
+			userSucceeded, responseTime = playIterations(maxNumber, true)
+		}
+		iterations++
+		averageTime = (averageTime*(iterations-1) + responseTime) / iterations
+		if userSucceeded == false {
+			fmt.Println("Oops, you got that last one wrong...")
+			goodbye()
+		}
+	}
+}
+
+func randomInt(min, max int) int {
+	return min + rand.Intn(max-min)
+}
+
+func playIterations(top int, hexTodec bool) (bool, int64) {
+	rand.Seed(time.Now().UnixNano())
+	n := randomInt(0, top)
+	var nForDisplay string
+	t := time.Now()
+	secs := t.Unix()
+
+	if hexTodec == true {
+		nForDisplay = fmt.Sprintf("0x%x", n)
+	} else {
+		nForDisplay = strconv.Itoa(n)
+	}
+
+	var responseTime int64
+	var convert string
+	for true {
+		fmt.Printf("* %s = ", nForDisplay)
+		reader := bufio.NewReader(os.Stdin)
+		input, _ := reader.ReadString('\n')
+		input = strings.TrimSuffix(input, "\r\n")
+		t2 := time.Now()
+		secs2 := t2.Unix()
+		responseTime = secs2 - secs
+		if hexTodec == true {
+			newNum, _ := strconv.Atoi(input)
+			convert = strconv.FormatInt(int64(newNum), 16)
+			convert = "0x" + convert
+		} else {
+			input = "0x" + input
+			newNum, _ := strconv.ParseInt(input, 0, 64)
+			convert = strconv.FormatInt(int64(newNum), 10)
+		}
+		break
+	}
+	return convert == nForDisplay, responseTime
+}
+
+func goodbye() {
+	fmt.Printf("\nYou placed %d iterations and your average response time was %d seconds.", iterations, averageTime)
+	os.Exit(0)
+}
+
+func signalHandler() {
+	c := make(chan os.Signal, 2)
+	signal.Notify(c, os.Interrupt, syscall.SIGTERM)
+	go func() {
+		<-c
+		fmt.Println("\n CTRL+C pressed in terminal")
+		goodbye()
+	}()
+}
+
+func main() {
+	maxNumber, gameMode := welcome()
+	play(maxNumber, gameMode)
+
+}