function load() {
	// track has ended
	document.getElementById('player').addEventListener('ended', function() {
		// shuffle
		if (document.getElementById('shuffle').checked) {
			fetch(api_uri + '/random').then(function(response) {
				return response.json();
			}).then(function(json) {
				change_track(json);
			});
		}
	});
}

function select_artist(select) {
	let params = {
		artist: select.value,
	};
	let query = Object.keys(params)
		.map(k => encodeURIComponent(k) + '=' + encodeURIComponent(params[k]))
		.join('&');
	fetch(api_uri + '?' + query).then(function(response) {
		return response.json();
	}).then(function(json) {
		let html_str = '';
		for (let i = 0; i < json.length; i++) {
			html_str += '<option value="' + json[i] + '">' + json[i] + '</option>';
		}
		document.getElementById('albumList').innerHTML = html_str;
		document.getElementById('trackList').innerHTML = '';
	});
}

function select_album(select) {
	let params = {
		artist: document.getElementById('artistList').value,
		album: select.value,
	};
	let query = Object.keys(params)
		.map(k => encodeURIComponent(k) + '=' + encodeURIComponent(params[k]))
		.join('&');
	fetch(api_uri + '?' + query).then(function(response) {
		return response.json();
	}).then(function(json) {
		let html_str = '';
		for (let i = 0; i < json.length; i++) {
			html_str += '<option data-discnumber="' + json[i][0] + '" data-tracknumber="' + json[i][1]+ '" value="' + json[i][2] + '">' + json[i][0] + '.' + json[i][1] + ' - ' + json[i][2] + '</option>';
		}
		document.getElementById('trackList').innerHTML = html_str;
	});
}

function select_track(select) {
	let params = {
		artist: document.getElementById('artistList').value,
		album: document.getElementById('albumList').value,
		discnumber: select.selectedOptions[0].dataset.discnumber,
		tracknumber: select.selectedOptions[0].dataset.tracknumber,
	};
	let query = Object.keys(params)
		.map(k => encodeURIComponent(k) + '=' + encodeURIComponent(params[k]))
		.join('&');
	fetch(api_uri + '?' + query).then(function(response) {
		return response.json();
	}).then(function(json) {
		change_track(json);
	});
}

function change_track(track) {
	let params = {
		artist: track.artist,
		album: track.album,
		discnumber: track.discnumber,
		tracknumber: track.tracknumber,
	};
	let query = Object.keys(params)
		.map(k => encodeURIComponent(k) + '=' + encodeURIComponent(params[k]))
		.join('&');

	let source = document.getElementById('stream');
	source.src = document.location.href + '/stream?' + query;
	let player = document.getElementById('player');
	player.load();
	player.play();
	document.getElementById('nowPlayingArtist').innerHTML = track.artist;
	document.getElementById('nowPlayingAlbum').innerHTML = track.album;
	document.getElementById('nowPlayingTitle').innerHTML = track.title;

	document.getElementById('albumCover').firstChild.src = document.location.href + 'coverart?' + query;
}