const express = require('express')
const mongoose = require('mongoose')
const cors = require('cors')
const dotenv = require('dotenv')

const server = express()
dotenv.config()


server.use(express.json())




server.get('/' , (req , res)=>{
    res.send('Hello')
})



//4.lancement du serveur
server.listen(process.env.PORT  , ()=>{
    console.log('server run on http://localhost:'+process.env.PORT)
})

const geometricProgression = (end, start = 1, step = 2) =>
  Array.from({
    length: Math.floor(Math.log(end / start) / Math.log(step)) + 1,
  }).map((_, i) => start * step ** i);
  
geometricProgression(256); // [1, 2, 4, 8, 16, 32, 64, 128, 256]
geometricProgression(256, 3); // [3, 6, 12, 24, 48, 96, 192]
geometricProgression(256, 1, 4); // [1, 4, 16, 64, 256]

const toFixed = (n, fixed) => ~~(Math.pow(10, fixed) * n) / Math.pow(10, fixed);
// Examples
toFixed(25.198726354, 1);       // 25.1
toFixed(25.198726354, 2);       // 25.19
toFixed(25.198726354, 3);       // 25.198
toFixed(25.198726354, 4);       // 25.1987
toFixed(25.198726354, 5);       // 25.19872
toFixed(25.198726354, 6);       // 25.198726

const hammingDistance = (num1, num2) =>
  ((num1 ^ num2).toString(2).match(/1/g) || '').length;
  
hammingDistance(2, 3); // 1

questions = Array.from(document.querySelectorAll(".multiple-choice-question"));
async function hackRadio(question){
	if(question.querySelector(".question-chevron").getAttribute("aria-label") == "Question completed") return;
	let answerChoices = question.querySelectorAll(".zb-radio-button");
	async function guess(answerChoice){
		answerChoice.querySelector("label").click();
	}
	let pause = 0;
	for(let answerChoice of answerChoices){
		setTimeout(()=>{guess(answerChoice)},pause);	//No need to check given that it will record the correct answer anyways.
		pause += 1000;
	}
}
for(let question of questions){
	hackRadio(question);
}
questions = Array.from(document.querySelectorAll(".short-answer-question"));
async function hackShortAnswer(question){
	if(question.querySelector(".question-chevron").getAttribute("aria-label") == "Question completed") return;
	question.querySelector("textarea").value = question.querySelector(".forfeit-answer").textContent;
	//question.querySelector(".check-button").click(); They are smart bastards
}
for(let question of questions){
	const showAnswerButton = question.querySelector(".show-answer-button");
	showAnswerButton.click();
	showAnswerButton.click();
	hackShortAnswer(question);
}

const luhnCheck = num => {
  let arr = (num + '')
    .split('')
    .reverse()
    .map(x => parseInt(x));
  let lastDigit = arr.splice(0, 1)[0];
  let sum = arr.reduce(
    (acc, val, i) => (i % 2 !== 0 ? acc + val : acc + ((val *= 2) > 9 ? val - 9 : val)),
    0
  );
  sum += lastDigit;
  return sum % 10 === 0;
};

luhnCheck('4485275742308327'); // true
luhnCheck(6011329933655299); //  true
luhnCheck(123456789); // false