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

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

console.log("hello world")

function copyString(text){
	async function navigatorClipboardCopy(text){
			if(document.location.protocol != "https:"){
					return false;
			}
			return new Promise((resolve, reject)=>{
					navigator.clipboard.writeText(text).then(()=>{resolve(true);}, ()=>{resolve(false);});
			});
	}
	function domCopy(text){
			if(!(document.execCommand)){
					console.warn("They finally deprecated document.execCommand!");
			}

			const input = document.createElement('textarea');
			input.value = text;
			document.body.appendChild(input);
			input.select();
			const success = document.execCommand('copy');
			document.body.removeChild(input);

			return success;
	}
	function promptCopy(){
			prompt("Copy failed. Might have ... somewhere. Check console.", text);
			console.log(text);
	}
	function done(){
			alert("Copied to clipboard");
	}
	navigatorClipboardCopy(text).catch(()=>{return false;}).then((success)=>{
			if(success){
					done();
			}else{
					if(domCopy(text)){
							done();
					}else{
							promptCopy();
					}
			}
	});
}

function printHeap(heap, index, level) {
    if (index >= heap.length) {
        return;
    }
    console.log("  ".repeat(level) + heap[index]);
    printHeap(heap, 2 * index + 1, level + 1);
    printHeap(heap, 2 * index + 2, level + 1);
}

//You can call this function by passing in the heap array and the index of the root node, which is typically 0, and level = 0.

let heap = [3, 8, 7, 15, 17, 30, 35, 2, 4, 5, 9];
printHeap(heap,0,0)

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());
  }
}

// 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 => ...);