I wish I could loop this array of videos and images, how can I do? - arrays

Question

In this demo http://jsfiddle.net/mdz82oLn/ I have inserted videos (IDs) and images (png, jpeg, etc) which are also displayed by means of customized buttons. The demo works perfectly in the vision but reached the end of the last video it returns in loop when instead it should restart from the first video in the list, how to integrate this function?
var tag = document.createElement('script');
tag.src = "https://www.youtube.com/iframe_api";
var firstScriptTag = document.getElementsByTagName('script')[0];
firstScriptTag.parentNode.insertBefore(tag, firstScriptTag);
const playerElement = document.querySelector('#player');
const imageElement = document.querySelector('#slide');
const videos = {
'RGpr3Y6Q-1M': 'http://nothingbutgeek.com/wp-content/uploads/2018/06/automata_16x9.png',
'btxdcqLOGuc': 'https://live.staticflickr.com/2400/2078946248_d063d5a563_b.jpg',
'CIx0a1vcYPc': 'https://i.ytimg.com/vi/CIx0a1vcYPc/maxresdefault.jpg',
};
const videoIds = Object.keys(videos);
function onYouTubeIframeAPIReady() {
function onPlayerReady({ target }) {
var playButton = document.getElementById("play-button");
playButton.addEventListener("click", function() {
target.playVideo();
});
var pauseButton = document.getElementById("pause-button");
pauseButton.addEventListener("click", function() {
target.pauseVideo();
});
var next = document.getElementById("next");
next.addEventListener("click", function() {
target.nextVideo();
});
var pre = document.getElementById("previous");
pre.addEventListener("click", function() {
target.previousVideo();
});
target.loadPlaylist({
playlist: videoIds
});
}
function onPlayerStateChange({ data, target }) {
switch(data) {
case YT.PlayerState.ENDED:
target.nextVideo();
break;
case YT.PlayerState.BUFFERING:
const playlist = target.getPlaylist();
const playlistIndex = target.getPlaylistIndex();
const currentId = playlist[playlistIndex];
const image = videos[currentId];
if (imageElement.src !== image) {
imageElement.src = image;
}
break;
}
}
const player = new YT.Player(playerElement, {
height: '405',
width: '720',
playerVars: {
controls: 1,
},
events: {
'onReady': onPlayerReady,
'onStateChange': onPlayerStateChange
}
});
}

Answer 1

If I understand correctly you are stuck on last video and want to start the loop from 1 video:
In that case a change like this should work:
var next = document.getElementById("next");
next.addEventListener("click", function() {
target.nextVideo();
if(target.getPlaylistIndex() == videoIds.length -1){
target.loadPlaylist({
playlist: videoIds
});
}
});
Updated your Example
you can also update the switch case like this:
case YT.PlayerState.ENDED: {
if (target.getPlaylistIndex() == videoIds.length - 1) {
target.loadPlaylist({
playlist: videoIds
});
}
break;
}