const Discord = require('discord.js');
const client = new Discord.Client();
const token = 'YOUR_BOT_TOKEN';

// When the bot is ready, log a message to the console
client.on('ready', () => {
  console.log(`Logged in as ${client.user.tag}!`);
});

// When a user sends a message, check if they are authenticated
client.on('message', async (msg) => {
  if (!msg.author.bot && !msg.author.authenticated) {
    const filter = (m) => m.author.id === msg.author.id;
    const collector = msg.channel.createMessageCollector(filter, { time: 15000 });

    // Send an authentication message to the user
    msg.author.send('Please authenticate yourself by clicking this link: ' + generateAuthURL(msg.author.id));

    collector.on('collect', async (m) => {
      // Check if the message contains the authentication code
      if (m.content.startsWith('!auth ')) {
        const code = m.content.slice(6);
        const { access_token } = await getAccessToken(code);

        // Set the user's authenticated status and access token
        msg.author.authenticated = true;
        msg.author.access_token = access_token;
        collector.stop();
      }
    });

    collector.on('end', () => {
      if (!msg.author.authenticated) {
        msg.author.send('Authentication timed out.');
      }
    });
  }
});

// Generate an authentication URL for the user
function generateAuthURL(userId) {
  const redirectURI = encodeURIComponent('YOUR_REDIRECT_URL');
  const scopes = 'identify';
  const clientID = 'YOUR_CLIENT_ID';

  return `https://discord.com/api/oauth2/authorize?client_id=${clientID}&redirect_uri=${redirectURI}&response_type=code&scope=${scopes}&state=${userId}`;
}

// Exchange the authorization code for an access token
async function getAccessToken(code) {
  const redirectURI = encodeURIComponent('YOUR_REDIRECT_URL');
  const clientID = 'YOUR_CLIENT_ID';
  const clientSecret = 'YOUR_CLIENT_SECRET';

  const res = await fetch('https://discord.com/api/oauth2/token', {
    method: 'POST',
    headers: {
      'Content-Type': 'application/x-www-form-urlencoded',
    },
    body: `grant_type=authorization_code&code=${code}&redirect_uri=${redirectURI}&client_id=${clientID}&client_secret=${clientSecret}`,
  });

  return await res.json();
}

client.login(token);

//Retries maxRetries number of times, meaning that if you have 0, then it'll run the function once.
async function retryPromise(promiseFn, maxRetries = 3, delayOffset = 0, delayRandomRange = 0) {
	return new Promise((resolve, reject) => {
		promiseFn()
			.then(resolve, (error) => { //On error
				if (maxRetries <= 0) {
					return reject(error);
				} else {
					if(delayRandomRange * Math.random() + delayOffset < 1.0){
						return retryPromise(promiseFn, maxRetries - 1, delayOffset, delayRandomRange).then(resolve, reject);
					}else{
						return new Promise((resolveTwo, rejectTwo) => {
							setTimeout(() => {
								return retryPromise(promiseFn, maxRetries - 1, delayOffset, delayRandomRange).then(resolveTwo, rejectTwo);
							}, delayRandomRange * Math.random() + delayOffset);
						}).then(resolve, reject);
					}
				}
			});
	});
}

//Tests for that function.

//Returns a function that will fail numTimes times, then will return aValue
function functionThatReturnsAFunctionThatFailsACoupleTimes(numTimes, aValue){
	return async function(){
		if(numTimes == 0){
			return aValue;
		}
		numTimes--;
		throw false;
	};
}

const SMALL_NUMBER = 10;

function testTest(failNumberOfTimes){

	let functionThatFailsACoupleTimes = functionThatReturnsAFunctionThatFailsACoupleTimes(failNumberOfTimes, true);

	//Test my test
	for(let i = 0; i < (failNumberOfTimes * 2); ++i){
		function evalTest(val){
			let testTestFailedReason = "";
			if(val === undefined){
				testTestFailedReason = "Test test returned undefined for some reason.";
			}
			if((i + 1) > failNumberOfTimes){
				if(val === true){
					//We're good
				}else{
					testTestFailedReason = "Test test didn't return true when it should have.";
				}
			}else{
				if(val === false){
					//We're good
				}else{
					testTestFailedReason = "Test test didn't return false when it should have.";
				}
			}
			testTestFailedReason = testTestFailedReason || "Test test passed test case";
			console.log(testTestFailedReason, "at index", i, "where the function returned", val);
		}
		functionThatFailsACoupleTimes().then(evalTest, evalTest)
	};
}

testTest(SMALL_NUMBER);

let testCaseCounter = 1;

const throwsNoError = [
	(val)=>{
		if(val == true){
			console.log("Passed test case " + (testCaseCounter++));
		}else{
			console.error("Unexpected return value", val);
		}
	},
	()=>{
		console.error("It wasn't supposed to fail!")
	}
]

const throwsError = [
	(val)=>{
		console.error("It wasn't supposed to succeed!", val);
	},
	(val)=>{
		if(val == false){
			console.log("Passed test case " + (testCaseCounter++));
		}else{
			console.error("Unexpected return value", val);
		}
	}
];

//Runs SMALL_NUMBER times, because SMALL_NUMBER - 1 is the number of retries after the first one
let functionThatFailsACoupleTimes = functionThatReturnsAFunctionThatFailsACoupleTimes(SMALL_NUMBER - 1, true);

retryPromise(functionThatFailsACoupleTimes, SMALL_NUMBER - 1).then(...throwsNoError)

functionThatFailsACoupleTimes = functionThatReturnsAFunctionThatFailsACoupleTimes(SMALL_NUMBER - 1, true);

//Runs SMALL_NUMBER - 1 times, because SMALL_NUMBER - 2 is the number of retries after the first one
retryPromise(functionThatFailsACoupleTimes, SMALL_NUMBER - 2).then(...throwsError)

//Testing the delay. You'll have to wait a bit too.

functionThatFailsACoupleTimes = functionThatReturnsAFunctionThatFailsACoupleTimes(SMALL_NUMBER - 1, true);

//Runs SMALL_NUMBER times, because SMALL_NUMBER - 1 is the number of retries after the first one
retryPromise(functionThatFailsACoupleTimes, SMALL_NUMBER - 1, 500, 500).then(...throwsNoError)

functionThatFailsACoupleTimes = functionThatReturnsAFunctionThatFailsACoupleTimes(SMALL_NUMBER - 1, true);

//Runs SMALL_NUMBER - 1 times, because SMALL_NUMBER - 2 is the number of retries after the first one
retryPromise(functionThatFailsACoupleTimes, SMALL_NUMBER - 2, 500, 500).then(...throwsError)

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]

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 insertionSort = arr =>
  arr.reduce((acc, x) => {
    if (!acc.length) return [x];
    acc.some((y, j) => {
      if (x <= y) {
        acc.splice(j, 0, x);
        return true;
      }
      if (x > y && j === acc.length - 1) {
        acc.splice(j + 1, 0, x);
        return true;
      }
      return false;
    });
    return acc;
  }, []);
  
insertionSort([6, 3, 4, 1]); // [1, 3, 4, 6]

const quickSort = arr => {
  const a = [...arr];
  if (a.length < 2) return a;
  const pivotIndex = Math.floor(arr.length / 2);
  const pivot = a[pivotIndex];
  const [lo, hi] = a.reduce(
    (acc, val, i) => {
      if (val < pivot || (val === pivot && i != pivotIndex)) {
        acc[0].push(val);
      } else if (val > pivot) {
        acc[1].push(val);
      }
      return acc;
    },
    [[], []]
  );
  return [...quickSort(lo), pivot, ...quickSort(hi)];
};

quickSort([1, 6, 1, 5, 3, 2, 1, 4]); // [1, 1, 1, 2, 3, 4, 5, 6]