function load() {
	// track has ended
	document.getElementById('player').addEventListener('ended', function() {
		// shuffle
		if (document.getElementById('shuffle').checked) {
			ajax('/musik/get_shuffle', function() {
				if (httpRequest.readyState !== XMLHttpRequest.DONE) { return; }
				if (httpRequest.status !== 200) { return; }
				let track = httpRequest.responseText;
				change_track(track);
			});
		}
	});
}

var httpRequest;
function ajax(url, func) {
	httpRequest = new XMLHttpRequest();
	httpRequest.onreadystatechange = func;
	httpRequest.open('GET', url, true);
	httpRequest.send();
}

function navigate(item) {
	if (/\..{3,5}$/.test(item)) {
		select_track(item);
	}
	else {
		get_dir(item);
	}
}

function select_track(item) {
	let cd = document.getElementById('currentDirectory').innerText;
	let track = cd + item;
	change_track(track);
}

function change_track(track) {
	let source = document.getElementById('stream');
	source.src = '/musik/stream' + encodeURIComponent(track);
	let player = document.getElementById('player');
	player.load();
	player.play();
	document.getElementById('nowPlaying').innerHTML = track;

	let arr = track.split('/');
	let art = document.getElementById('albumCover');
	art.firstChild.src = '/musik/album_cover' + arr.slice(0, arr.length-1).join("/") + '/folder.jpg';
}

function get_dir(item) {
	let cd = document.getElementById('currentDirectory').innerText;
	if (item === "../") {
		if (cd !== "/") {
			item = cd.slice(0, cd.slice(0, -1).lastIndexOf("/")+1);
		}
		else {
			return;
		}
	}
	else {
		item = cd + item;
	}
	ajax('/musik/get_dir/' + item, update_nav_items);
}

function update_nav_items() {
	if (httpRequest.readyState !== XMLHttpRequest.DONE) { return; }
	if (httpRequest.status !== 200) { return; }
	nav_items = JSON.parse(httpRequest.responseText);
	document.getElementById('currentDirectory').innerText = nav_items.shift();
	let html_str = '';
	for (let i = 0; i < nav_items.length; i++) {
		html_str += `<li><a href="javascript:void(0);" onclick="navigate(\`${nav_items[i]}\`)">${nav_items[i]}</a></li>`;
	}
	document.getElementById('navItems').innerHTML = html_str;
}