drag and drop folder upload JavaScript with php

<!-- Drag Drop Upload Code -->

<p>Drag files and/or directories to the box below!</p>

<div id="dropzone">
  <div id="boxtitle">
    Drop Files Here
  </div>
</div>

<h2>Directory tree:</h2>

<ul id="listing"></ul>

<script>
var dropzone = document.getElementById("dropzone");
var listing = document.getElementById("listing");

function scanAndLogFiles(item, container) {
  var elem = document.createElement("li");
  elem.innerHTML = item.name;
  container.appendChild(elem);
  if (item.isDirectory) {
    console.log('DIR '+item.webkitRelativePath);
  }
  if (item.isFile) {
    console.log('FILE '+item.webkitRelativePath);
  }
  if (item.isDirectory) {
    var directoryReader = item.createReader();
    var directoryContainer = document.createElement("ul");
    container.appendChild(directoryContainer);

    directoryReader.readEntries(function(entries) {
      entries.forEach(function(entry) {
        scanAndLogFiles(entry, directoryContainer);
      });
    });
  }
}

dropzone.addEventListener(
  "dragover",
  function(event) {
    event.preventDefault();
  },
  false
);

dropzone.addEventListener(
  "drop",
  function(event) {
    var items = event.dataTransfer.items;

    event.preventDefault();
    listing.innerHTML = "";

    for (var i = 0; i < items.length; i++) {
      var item = items[i].webkitGetAsEntry();

      if (item) {
        scanAndLogFiles(item, listing);
      }
    }
  },
  false
);
</script>
<style>
#dropzone {
  text-align: center;
  width: 300px;
  height: 100px;
  margin: 10px;
  padding: 10px;
  border: 4px dashed red;
  border-radius: 10px;
}

#boxtitle {
  display: table-cell;
  vertical-align: middle;
  text-align: center;
  color: black;
  font: bold 2em "Arial", sans-serif;
  width: 300px;
  height: 100px;
}
</style>