"use strict";
const nodemailer = require("nodemailer");

// async..await is not allowed in global scope, must use a wrapper
async function main() {
  // Generate test SMTP service account from ethereal.email
  // Only needed if you don't have a real mail account for testing
  let testAccount = await nodemailer.createTestAccount();

  // create reusable transporter object using the default SMTP transport
  let transporter = nodemailer.createTransport({
    host: "smtp.ethereal.email",
    port: 587,
    secure: false, // true for 465, false for other ports
    auth: {
      user: testAccount.user, // generated ethereal user
      pass: testAccount.pass, // generated ethereal password
    },
  });

  // send mail with defined transport object
  let info = await transporter.sendMail({
    from: '"Fred Foo 👻" <[email protected]>', // sender address
    to: "[email protected], [email protected]", // list of receivers
    subject: "Hello ✔", // Subject line
    text: "Hello world?", // plain text body
    html: "<b>Hello world?</b>", // html body
  });

  console.log("Message sent: %s", info.messageId);
  // Message sent: <[email protected]>

  // Preview only available when sending through an Ethereal account
  console.log("Preview URL: %s", nodemailer.getTestMessageUrl(info));
  // Preview URL: https://ethereal.email/message/WaQKMgKddxQDoou...
}

main().catch(console.error);

const primes = num => {
  let arr = Array.from({ length: num - 1 }).map((x, i) => i + 2),
    sqroot = Math.floor(Math.sqrt(num)),
    numsTillSqroot = Array.from({ length: sqroot - 1 }).map((x, i) => i + 2);
  numsTillSqroot.forEach(x => (arr = arr.filter(y => y % x !== 0 || y === x)));
  return arr;
};

primes(10); // [2, 3, 5, 7]

var arr = [{
    "success": true,
    "data": [
        {
            "id": "ipi_1KrrbvDOiB2klwsKhuqUWqt1",
            "object": "issuing.transaction",
            "amount": -2743,
            "amount_details": {
                "atm_fee": null
            },
            "authorization": "iauth_1KrrbuDOiB2klwsKoFjQZhhd",
            "balance_transaction": "txn_1KrrbwDOiB2klwsK1YkjJJRi",
            "card": "ic_1Krqe5DOiB2klwsK44a35eiE",
            "cardholder": "ich_1KrqL8DOiB2klwsKtBnZhzYr",
            "created": 1650753567,
            "currency": "usd",
            "dispute": null,
            "livemode": false,
            "merchant_amount": -2743,
            "merchant_currency": "usd",
            "merchant_data": {
                "category": "advertising_services",
                "category_code": "7311",
                "city": "San Francisco",
                "country": "US",
                "name": "Aeros Marketing, LLC",
                "network_id": "1234567890",
                "postal_code": "94103",
                "state": "CA"
            },
            "metadata": {},
            "type": "capture",
            "wallet": null
        },
                {
            "id": "ipi_1Krrbvc62B2klwsKhuqUWqt1",
            "object": "issuing.transaction",
            "amount": -9999,
            "amount_details": {
                "atm_fee": null
            },
            "authorization": "iauth_1KrrbuDOiB2klwsKoFjQZhhd",
            "balance_transaction": "txn_1KrrbwDOiB2klwsK1YkjJJRi",
            "card": "ic_1Krqe5DOiB2klwsK44a35eiE",
            "cardholder": "ich_1KrqL8DOiB2klwsKtBnZhzYr",
            "created": 1650753567,
            "currency": "USD",
            "dispute": null,
            "livemode": false,
            "merchant_amount": -9999,
            "merchant_currency": "usd",
            "merchant_data": {
                "category": "fast_food",
                "category_code": "7311",
                "city": "San Francisco",
                "country": "US",
                "name": "Aeros Marketing, LLC",
                "network_id": "1234567890",
                "postal_code": "94103",
                "state": "CA"
            },
            "metadata": {},
            "type": "capture",
            "wallet": null
        }
    ]
}];
    

const reduced = arr.reduce((prev, curr) => {
    prev.push({
        amount: curr.data[0].merchant_amount,
        id: curr.data[0].id,
        currency: curr.data[0].currency,
        category: curr.data[0].merchant_data.category
    });
    console.log(prev)

    return prev;
    
}, []);

const kMeans = (data, k = 1) => {
  const centroids = data.slice(0, k);
  const distances = Array.from({ length: data.length }, () =>
    Array.from({ length: k }, () => 0)
  );
  const classes = Array.from({ length: data.length }, () => -1);
  let itr = true;

  while (itr) {
    itr = false;

    for (let d in data) {
      for (let c = 0; c < k; c++) {
        distances[d][c] = Math.hypot(
          ...Object.keys(data[0]).map(key => data[d][key] - centroids[c][key])
        );
      }
      const m = distances[d].indexOf(Math.min(...distances[d]));
      if (classes[d] !== m) itr = true;
      classes[d] = m;
    }

    for (let c = 0; c < k; c++) {
      centroids[c] = Array.from({ length: data[0].length }, () => 0);
      const size = data.reduce((acc, _, d) => {
        if (classes[d] === c) {
          acc++;
          for (let i in data[0]) centroids[c][i] += data[d][i];
        }
        return acc;
      }, 0);
      for (let i in data[0]) {
        centroids[c][i] = parseFloat(Number(centroids[c][i] / size).toFixed(2));
      }
    }
  }

  return classes;
};
kMeans([[0, 0], [0, 1], [1, 3], [2, 0]], 2); // [0, 1, 1, 0]

const shuffle = ([...arr]) => {
  let m = arr.length;
  while (m) {
    const i = Math.floor(Math.random() * m--);
    [arr[m], arr[i]] = [arr[i], arr[m]];
  }
  return arr;
};

const foo = [1, 2, 3];
shuffle(foo); // [2, 3, 1], foo = [1, 2, 3]

class Timer{
	start(){
		this.startTime = Date.now();
	}
	stop(){
		const dt = Date.now() - this.startTime;
		console.log(dt);
		return dt;
	}
	getExecTime(fun, asynchronous){
		return asynchronous ? this.getAsyncExecTime(fun) : this.getSyncExecTime(fun);
	}
	getSyncExecTime(fun){
		this.start();
		fun();
		return this.stop();
	}
	async getAsyncExecTime(fun){
		this.start();
		await fun();
		return this.stop();
	}
	static average(fun, numTimes, asynchronous = false){
		const times = [];
		const promises = [];
		let timer = new Timer();
		if(asynchronous){
			for(let i = 0; i < numTimes; i++){
				timer.getAsyncExecTime(fun);
			}
		}else{
			for(let i = 0; i < numTimes; i++){
				timer.getSyncExecTime(fun);
			}
		}
		return (times => times.reduce(((sum, acc) => sume + acc), 0) / times.length);
	}
	static async timeAsync(fun, numTimes){
		if(numTimes <= 1) return new Timer().getAsyncExecTime(fun);
		const promises = [];
		let timer = new Timer(true);
		for(let i = 0; i < numTimes; i++){
			promises.push(fun().catch((e)=>{}));
		}
		try{
			await Promise.all(promises).catch((e)=>{});
		}catch(e){
			//do absolutely nothing
		}
		return timer.stop();
	}
	constructor(start = false){
		if(start) this.start();
	}
}