// `date` is a `Date` object
const formatYmd = date => date.toISOString().slice(0, 10);

// Example
formatYmd(new Date());      // 2020-05-06

//Use at https://mee6.xyz/leaderboard/732262089447702588
//Higher the spammy stat, the more spammy that person is.
//This is because mee doesn't give experience to people who post more comments in a minute.
function statBlock(title, value){
	let elm = document.createElement("div");
	elm.className = "leaderboardPlayerStatBlock";
	let titleElm = document.createElement("div");
	titleElm.className = "leaderboardPlayerStatName";
	titleElm.textContent = title;
	let valueElm = document.createElement("div");
	valueElm.className = "leaderboardPlayerStatValue";
	valueElm.textContent = value;
	elm.appendChild(titleElm);
	elm.appendChild(valueElm);
	elm.remove = function(){
	this.parentElement.removeChild(this);
	}
	return elm;
}
for(let player of Array.from(document.getElementsByClassName("leaderboardPlayer"))){
	if(player.spamminess) player.spamminess.remove();
	let messages = null;
	let experience = null;
	const statBlockArray = Array.from(player.querySelectorAll(".leaderboardPlayerStatBlock"));
	for(let statBlock of statBlockArray){
	const statName = statBlock.querySelector(".leaderboardPlayerStatName").textContent;
	const text = statBlock.querySelector(".leaderboardPlayerStatValue").textContent;
	const number = ((text.includes("k"))? (text.replace("k","") * 1000.0) : +(text));
	if(statName.includes("MESSAGES")){
	messages = number;
	}else if(statName.includes("EXPERIENCE")){
	experience = number;
	}
	}
	const stats = player.querySelector(".leaderboardPlayerStats");
	const messagesElement = stats.firstChild;

	const spamminess = ((messages/experience)*2000.0).toFixed(2);
	
	player.spamminess = stats.insertBefore(statBlock("SPAMMINESS", spamminess), messagesElement);
}

console.log("hello world")

const arithmeticProgression  = (n, lim) =>
  Array.from({ length: Math.ceil(lim / n) }, (_, i) => (i + 1) * n );
  
arithmeticProgression(5, 25); // [5, 10, 15, 20, 25]

function formatDate(date) {
  return date.toLocaleDateString();
}

function Comment(props) {
  return (
    <div className="Comment">
      <div className="UserInfo">
        <img
          className="Avatar"
          src={props.author.avatarUrl}
          alt={props.author.name}
        />
        <div className="UserInfo-name">
          {props.author.name}
        </div>
      </div>
      <div className="Comment-text">{props.text}</div>
      <div className="Comment-date">
        {formatDate(props.date)}
      </div>
    </div>
  );
}

const comment = {
  date: new Date(),
  text: 'I hope you enjoy learning React!',
  author: {
    name: 'Hello Kitty',
    avatarUrl: 'https://placekitten.com/g/64/64',
  },
};
ReactDOM.render(
  <Comment
    date={comment.date}
    text={comment.text}
    author={comment.author}
  />,
  document.getElementById('root')
);

// promisify(f, true) to get array of results
function promisify(f, manyArgs = false) {
  return function (...args) {
    return new Promise((resolve, reject) => {
      function callback(err, ...results) { // our custom callback for f
        if (err) {
          reject(err);
        } else {
          // resolve with all callback results if manyArgs is specified
          resolve(manyArgs ? results : results[0]);
        }
      }

      args.push(callback);

      f.call(this, ...args);
    });
  };
}

// usage:
f = promisify(f, true);
f(...).then(arrayOfResults => ..., err => ...);