//Copyright 2009 Joshua Saint

var slides = [];
var myPage = 1;

for (var c=0;c<25;c++) {
	var img = "jsabch/Slide" + (c+1) + ".jpg";
	slides[c] = new Image;
	slides[c].src = img;

}

function goPage(goToPage) {
	var page = goToPage - 1;
	myPage = goToPage;
	document.getElementById('slide').src = slides[page].src;
	updateNav();
}

function goFirst() {
	goPage(1);
}

function goLast() {
	goPage(25);
}

function goPrev() {
	if (myPage != 1) {
		goPage(myPage - 1);
	}
}

function goNext() {
	if (myPage != 25) {
		goPage(myPage + 1);
	}
}

function updateNav() {
	if (myPage == 1) {
		document.getElementById("first").className = 'nav_on';
		document.getElementById("prev").className = 'nav_on';
		document.getElementById("s1").className = 'nav_on';
		document.getElementById("next").className = 'nav_off';
		document.getElementById("last").className = 'nav_off';
		for (var c=2;c<26;c++) {
			document.getElementById("s" + c).className = 'nav_off';
		}
	}
	else if (myPage == 25) {
		document.getElementById("first").className = 'nav_off';
		document.getElementById("prev").className = 'nav_off';
		document.getElementById("s25").className = 'nav_on';
		document.getElementById("next").className = 'nav_on';
		document.getElementById("last").className = 'nav_on';
		for (var c=1;c<25;c++) {
			document.getElementById("s" + c).className = 'nav_off';
		}
	}
	else {
		document.getElementById("first").className = 'nav_off';
		document.getElementById("prev").className = 'nav_off';
		document.getElementById("next").className = 'nav_off';
		document.getElementById("last").className = 'nav_off';
		document.getElementById("s" + myPage).className = 'nav_on';
		for (var c=1;c<26;c++) {
			if (c != myPage) {
				document.getElementById("s" + c).className = 'nav_off';
			}
		}	
	
	}
}