// JavaScript Document
var minIndex = 1;
var curIndex = 1;
var maxIndex = 30;

var mode = "forward";

document.getElementById('d7').addEventListener('webkitTransitionEnd', onTransitionEnd, false);

var p1 = document.images[0];
var p2 = document.images[1];
var p3 = document.images[2];

p1.src = "";
p2.src = pic1.src;
p3.src = pic2.src;

var wiki = document.getElementById('link');

function goForward(){
	if (curIndex < maxIndex){		
		mode = "forward";
		for (i = 1; i <= 8; i++){
			document.getElementById('d'+String(i)).style.webkitTransitionDuration = "800ms";
		}
		for (i = 2; i <= 8; i++){
			document.getElementById('d'+String(i)).className = "layer"+String(i-1);
		}
		curIndex++;
	}
}

function onTransitionEnd(event){
	if (mode == "forward"){
		for (i = 1; i <= 8; i++){
			document.getElementById('d'+String(i)).style.webkitTransitionDuration = "0ms";
		}
		for (i = 2; i <= 8; i++){
			document.getElementById('d'+String(i)).className = "layer"+String(i);
		}
	} else{
		for (i = 1; i <= 8; i++){
			document.getElementById('d'+String(i)).style.webkitTransitionDuration = "0ms";
		}
		for (i = 1; i <= 7; i++){
			document.getElementById('d'+String(i)).className = "layer"+String(i);
		}
	}
	
	if (curIndex == minIndex){
		p1.src = "";
		p2.src = pic1.src;
		p3.src = pic2.src;
		gohome = false;
	}else if (curIndex == maxIndex){
		p1.src = pic29.src;
		p2.src = pic30.src;
		p3.src = "";
	}else{
		p1.src = eval("pic"+String(curIndex-1)+".src");
		p2.src = eval("pic"+String(curIndex)+".src");
		p3.src = eval("pic"+String(curIndex+1)+".src");
	}
	
	if (curIndex == 4){
		wikistr = '1976 to 1984: Development (<a href="http://en.wikipedia.org/wiki/Macintosh#1979_to_1984:_Development" target="_blank"><em>wiki it</em></a>)';
		wiki.innerHTML = wikistr;
	}else if (curIndex == 5){
		wikistr = '1984: Introduction (<a href="http://en.wikipedia.org/wiki/Macintosh#1984:_Introduction" target="_blank"><em>wiki it</em></a>)';
		wiki.innerHTML = wikistr;
	}else if (curIndex == 6 || curIndex == 10){
		wikistr = '1985 to 1989: Desktop publishing era (<a href="http://en.wikipedia.org/wiki/Macintosh#1985_to_1989:_Desktop_publishing_era" target="_blank"><em>wiki it</em></a>)';
		wiki.innerHTML = wikistr;
	}else if (curIndex == 11 || curIndex == 20){
		wikistr = '1990 to 1998: Growth and decline (<a href="http://en.wikipedia.org/wiki/Macintosh#1990_to_1998:_Growth_and_decline" target="_blank"><em>wiki it</em></a>)';
		wiki.innerHTML = wikistr;
	}else if (curIndex == 21 || curIndex == 27){
		wikistr = '1998 to 2005: The Rebirth (<a href="http://en.wikipedia.org/wiki/Macintosh#1998_to_2005:_The_Rebirth" target="_blank"><em>wiki it</em></a>)';
		wiki.innerHTML = wikistr;
	}else if (curIndex == 28){
		wikistr = '2006 onward: Intel era (<a href="http://en.wikipedia.org/wiki/Macintosh#2006_onward:_Intel_era" target="_blank"><em>wiki it</em></a>)';
		wiki.innerHTML = wikistr;
	}
}

function goBackward(){
	if (curIndex > minIndex){
		mode = "backward";
		for (i = 1; i <= 8; i++){
			document.getElementById('d'+String(i)).style.webkitTransitionDuration = "800ms";
		}
		for (i = 1; i <= 7; i++){
			document.getElementById('d'+String(i)).className = "layer"+String(i+1);
		}
		curIndex--;
	}
}

function goHome(){
	p1.src = "";
	p2.src = pic1.src;
	p3.src = pic2.src;
	curIndex = minIndex;
	wikistr = '1976 to 1984: Development (<a href="http://en.wikipedia.org/wiki/Macintosh#1979_to_1984:_Development" target="_blank"><em>wiki it</em></a>)';
	wiki.innerHTML = wikistr;
}