guess_the_number.js

"use strict";

let readline = require('readline');

class GuessTheNumber {

    randomBetween(min, max) {
        return Math.floor(Math.random() * (max - min + 1) + min);
    }

    guessAnswer(guess) {
      if(guess < this.answer) {
        return -1;
      } else if(guess > this.answer) {
        return 1;
      } else {
        return 0;
      }
    }

    answerMessage(answerCode) {
      if(answerCode < 0) {
        return "Too low";
      }
      if(answerCode > 0) {
        return "Too high";
      }
      return "Correct";
    }

    constructor() {
        this.min = 1;
        this.max = 1000;
        this.answer = this.randomBetween(this.min, this.max);
    }

}

const rl = readline.createInterface({
  input: process.stdin,
  output: process.stdout
});

function readGuess() {
  rl.question('Enter your guess: ', (answer) => {
    var result = game.guessAnswer(parseInt(answer));
    var message = game.answerMessage(result);

    console.log(message);
    if(result != 0) {
      readGuess(); // Ask again
    } else {
      rl.close();
    }
  });
}

let game = new GuessTheNumber();

console.log(`Guess the number! Between ${game.min} and ${game.max}`);
readGuess();