// JavaScript Document

//Script Initialization
addOnload(imgrolloverInit);
addOnload(startpix);


//Image to Image Rollover Functions
function imgrolloverInit()
{
	
	var j;
	for (var i=0; i<document.images.length; i++)
	
	{
		var elementID = document.images[i].id;
		var checkforNAV = (elementID.substring(0,11));
		
		if ( checkforNAV == "navRollover" )
		{  setupRollover(document.images[i]);  }
		
	}
}

function setupRollover(thisImage)
{
	thisImage.outImage = new Image();
	thisImage.outImage.src = thisImage.src;
	thisImage.onmouseout = rollOut;
	
	thisImage.overImage = new Image();
	//ADJUST THE NEXT LINE AS NECESSARY.  NOTE THE ADDRESS AT THE BEGINNING AND FILE TYPE AT THE END.
	thisImage.overImage.src = "http://dept.harpercollege.edu/library/images/mainpage/ovr_nav_" + thisImage.className + ".jpg";
	thisImage.onmouseover = rollOver;
}

function rollOver() { this.src = this.overImage.src; }

function rollOut()  { this.src = this.outImage.src; }


//Random Image Script
var imgSet = new Array("http://dept.harpercollege.edu/library/images/mainpage/main_rotation00.jpg", "http://dept.harpercollege.edu/library/images/mainpage/main_rotation01.jpg", "http://dept.harpercollege.edu/library/images/mainpage/main_rotation02.jpg", "http://dept.harpercollege.edu/library/images/mainpage/main_rotation03.jpg");

function choosePic() {
	randomNum = Math.floor((Math.random() * imgSet.length));
	
	document.getElementById("randomPicture").src = imgSet[randomNum];
}

//Rotating pictures
var defaultgallery = 0;
var galleries = new Array(1);
galleries[0]= new Array("Harper College Library","entrance","audio_books","front_desk","magazines","reading_area","stacks","stacks2","videos");

var brgall=0;
var brpic=1;
var brid;
function startpix() {
	brid=setInterval('browse()',10000);
}

function browse() {
	if (brpic>=galleries[brgall].length) {
		++brgall;
		brpic=1;
	}
	if (brgall<galleries.length) {	
		var b=document.getElementById("randomPicture");
		var bnewpic=galleries[brgall][brpic];
        var bnewpicid="images\/gallery\/" + bnewpic + ".jpg";
		b.src=bnewpicid;
        b.alt=bnewpic;
		++brpic;
		}
	else {	
       brgall=0;
	   brpic=1;
	   var b=document.getElementById("randomPicture");
	   b.src="images\/gallery\/main_rotation00.jpg";
	   b.alt="Harper College Library Pictures";
	   clearInterval(brid);
	}
}