/* Frame switch management. */

var currentId = 1;
var maxId = 0;
var framePrefix = "frame-";

function frameShow(id) {

	if(id > maxId)
		return;

	if(id < 1)
		return;

	if(id == currentId)
		return;

	newFrame = framePrefix + id;
	oldFrame = framePrefix + currentId;

	document.getElementById(oldFrame).className = framePrefix + "inactive";
	document.getElementById(newFrame).className = framePrefix + "active";
	
	currentId = id;

	if(currentId <= 1)
		document.getElementById("scr-left").src = "img/web-arrow-left-off.gif";
	else
		document.getElementById("scr-left").src = "img/web-arrow-left.gif";

	document.getElementById("scr-page").innerHTML = "Page "+ currentId + "/" + maxId;

	if(currentId >= maxId)
		document.getElementById("scr-right").src = "img/web-arrow-right-off.gif";
	else
		document.getElementById("scr-right").src = "img/web-arrow-right.gif";

	zoomOut(this, this);
}

function frameSetMaxId(id) {

	maxId = id;

	frameShow(currentId);
}

function frameShowPrev() {

	if(currentId <= 1)
		return;

	frameShow(currentId - 1);
}

function frameShowNext() {

	if(currentId >= maxId)
		return;

	frameShow(currentId + 1);
}