/* window name
----------------------------------------- */
window.name = "alvanoto";
window.focus();

/* audio track
----------------------------------------- */
var newTrackID = null;
var oldTrackID = null;
var newTrackURL = null;
var oldTrackURL = null;
var newAnchor = null;
var oldAnchor = null;

var newAudio = new Audio();

function playAudio(ID, URL) {
	newTrackID = ID;
	newTrackURL = URL;
	newAnchor = document.getElementById(newTrackID);
	
	if (oldTrackID != null) {
		newAudio.pause();
		oldAnchor = document.getElementById(oldTrackID);
		oldAnchor.style.backgroundImage='url(./c/img/btn_play.gif)';
		
		if (oldTrackID == newTrackID) {
			oldTrackID = null;
		} else {
			mainAudio(newTrackID, newTrackURL);
		}
	} else {
		mainAudio(newTrackID, newTrackURL);
	}
}

function mainAudio(mainTrackID, mainTrackURL) {
	oldTrackID = mainTrackID;
	if (newAudio.canPlayType("audio/mpeg") != "maybe") {
		mainTrackURL = mainTrackURL.replace(/\.mp3/, ".ogg");
	}
	(newAudio = new Audio(mainTrackURL)).play();
	newAnchor.style.backgroundImage='url(./c/img/btn_loading.gif)';
	
	newAudio.addEventListener("canplaythrough", function() {
		newAnchor.style.backgroundImage='url(./c/img/btn_stop.gif)';
	}, true);
	newAudio.addEventListener("ended", function() {
		newAnchor.style.backgroundImage='url(./c/img/btn_play.gif)';
	}, true);
}