console.log("xa")

const head = arr => (arr && arr.length ? arr[0] : undefined);

head([1, 2, 3]); // 1
head([]); // undefined
head(null); // undefined
head(undefined); // undefined

function filePath(file){
  let folders = file.getParents();
  const parents = [];

  function makePathString(folderArray){
    let path = "";
    folderArray.forEach((folder)=>{
      path += "/" + folder.getName();
    });
    return path;
  }
  
  while (folders.hasNext()) {
    const folder = folders.next(); //This should hopefully remove that folder from the iterator
    parents.unshift(folder);
  }

  return makePathString(parents);
}

function myFunction() {
  const myEmail = Session.getEffectiveUser().getEmail();
  Logger.log("My email is " + myEmail);
  // Log the name of every file in the user's Drive.
  var fileIterator = DriveApp.getFiles();
  const files = []; //List of [File, size] entries
  const filesMaxSize = 10;
  while (fileIterator.hasNext()) {
    var file = fileIterator.next();

    const owner = file.getOwner();

    //Only files I own
    if((!(owner)) || (!(owner.getEmail)) || owner.getEmail() != myEmail){
      continue;
    }

    const entry = [file, file.getSize()];

    function slideUp(arr, index){
      //Let's keep sliding it up so we don't have to sort it at the end.
      for(let i = index; i > 0; --i){ //Stops at 1
        const nextFile = arr[i-1];

        if(nextFile[1] > entry[1]){
          break;
        }else{
          //Swap with the next file to slide the file up
          const temp = arr[i];
          arr[i] = arr[i - 1];
          arr[i - 1] = temp;
        }
      }
    }

    if(files.length < filesMaxSize){
      files.push(entry);

      slideUp(files, files.length - 1);
    }else{
      if(entry[1] > files[files.length - 1][1]){ //If it's bigger than the smallest file in the list.
        files[files.length - 1] = entry;  //Replace the smallest file

        slideUp(files, files.length - 1); //Slide it up
      }
    }
  }

  for(let i = 0; i < filesMaxSize; ++i){
    const file = files[i][0];
    const size = files[i][1];
    Logger.log(size + "\t" + filePath(file) + "/" + file.getName() + "\t" + file.getOwner().getName());
  }
}

const flat = arr => [].concat.apply([], arr.map(a => Array.isArray(a) ? flat(a) : a));
// Or
const flat = arr => arr.reduce((a, b) => Array.isArray(b) ? [...a, ...flat(b)] : [...a, b], []);

// Or
// See the browser compatibility at https://caniuse.com/#feat=array-flat
const flat = arr => arr.flat();

// Example
flat(['cat', ['lion', 'tiger']]);   // ['cat', 'lion', 'tiger']

/**
 * @param {number[]} nums
 * @param {number} target
 * @return {number[]}
 */
var twoSum = function(nums, target) {
    for(let i = 0; i < nums.length; i++) {
        for(let j = 0; j < nums.length; j++) {
            if(nums[i] + nums[j] === target && i !== j) {
                return [i, j]
            }
        }
    }
};

require("dotenv").config();
const mongoose = require("mongoose");

const db = process.env.MONGO_URI;

const connectDB = async () => {
	try {
	await mongoose.connect(db, {
	useNewUrlParser: true,
	useUnifiedTopology: true,
	useFindAndModify: false,
	useCreateIndex: true
	});

	console.log("MongoDB Connected");
	} catch (err) {
	console.error(err.message);
	}
};

module.exports = connectDB;