var leds = new Array();
var message = new Array();
var readOffset = 0;
var displayWidth = 0;
var letterSpacing = 1;
var row = 0;

function setOpacity(led, amount) {
	var div = document.getElementById(led);
	div.lastChild.style.opacity = amount;
}

function getOpacity(led) {
	var div = document.getElementById(led);

	if (div) {
		var opac = div.lastChild.style.opacity;
		if (opac == "") opac = 1;
		return opac;
	 }
}

function turnOn(led) {
	var div = document.getElementById(led);
	if (div) {
		if (div.fadeEvent != null) {
			window.clearTimeout(div.fadeEvent);
		}
		div.lastChild.style.opacity = 1;
	}
}

function turnOff(led) {
	var div = document.getElementById(led);
	div.lastChild.style.opacity = 0.0;
}
function createLedMatrix(width, height) {
	var matrix = '';
	readOffset = - width;
	displayWidth = width;
	for (x = 0; x < width; x++) {
		for (y = 0; y < height; y++) {
			matrix += createLed(x, y);
			leds.push('l'+ x +'x' + y);
		}
	}
	document.getElementById('ledSet').innerHTML = matrix;
	allOff();
}

function createLed(x, y) {
	lc = ledColor;
	if (lc == 'rainbow') {
		lc = 'white';
		if (y % 7 == 0) lc = 'red';
		if (y % 7 == 1) lc = 'amber';
		if (y % 7 == 2) lc = 'yellow';
		if (y % 7 == 3) lc = 'green';
		if (y % 7 == 4) lc = 'blue';
		if (y % 7 == 5) lc = 'uv';
	}
	return '<div id="l'+ x +'x'+ y +'" class="led" style="top:'+ y*(ledSize + ledPadding) +'px;left:' + x*(ledSize + ledPadding) + 'px;"><img src="leds/'+lc+'-off-'+ledSize+'.png" class="off"/><img src="leds/'+lc+'-on-'+ledSize+'.png" class="on"/></div>';
}

function allOff() {
	for (x in leds) turnOff(leds[x]);
}

function allOn() {
	for (x in leds) turnOn(leds[x]);
}
function scroll() {
	readOffset++;
	if (readOffset > message.length) readOffset = -displayWidth;
	redraw();
	window.setTimeout(scroll, scrollDelay);
}

function redraw() { 
	partialmessage = message.slice(readOffset, readOffset + displayWidth);

	for (x in partialmessage) {
		for (y in partialmessage[x]) {
			if (x >= 0) { 
				if (partialmessage[x][y]) {
					turnOn('l'+x+'x'+y);
				}
				else { 
					turnOff('l'+x+'x'+y);
				} 
			}
		} 
	} 
} 


function addCharacter(c) {
	if (msg[c]) {
		for (x in msg[c]) {
			message.push(msg[msg[c][x]]);
		}
		for (x = 0; x < letterSpacing; x++) message.push(msg[0]);
	}
}
 
function setMessage(msg) {
	message = new Array();
	msg = msg.toUpperCase();
	msg = "     " + msg + " ";
	for (ch = 0; ch < msg.length; ch++) {
		c = msg.substr(ch,1);
		if (c=="0" || c=="1" || c=="2" || c=="3" || c=="4" || c=="5" || c=="6" || c=="7" || c=="8" || c=="9") addCharacter("n" + c);
		else addCharacter(c);
	}
}