window.onload=function(){
	if(!document.getElementById || !document.createTextNode){return;}
	domslides();
}

/* 
DOMSlides (v1.0)
written by Christian Heilmann
Licensed Creative Commons Attribution 2.5: http://creativecommons.org/licenses/by/2.5/
*/

/* Variables to change */
function domslides(){

	// Texts
	var tocLinkText='TOC';
	var tocCloseText='Close TOC';
	var counterText='(_x_/_y_)'; 
	var nextSlideText='Next >';
	var prevSlideText='< Previous';
	var titleAdd=' - ';

	// IDs
	var boundaryId='slideshow';
	var footerId='footer';
	var tocListId='toclist';
	var closeTocId='closeToc';
	var navigationForm='slide-nav';

	// Classes
	var jsIndicatorClass='js';
	var hideClass='hide';
	var slideClass='slide';
	var counterClass='counter';

	/* If you change things here, make sure you know what you are doing! */
	// Check if the needed markup is available
	var ds_error=false;
	if(!document.getElementById(boundaryId)){alert('Boundary Element is missing'); ds_error=true;}
	if(!document.getElementById(footerId)){alert('Footer Element is missing'); ds_error=true;}
	if(!document.getElementsByTagName('h1')[0]){alert('Heading not existant'); ds_error=true;}
	if(document.getElementsByTagName('h1')[0] && !document.getElementsByTagName('h1')[0].firstChild){alert('Heading has no content'); ds_error=true;}
	if(ds_error){return false;}

	// Generate the TOC list 
	var tocul=document.createElement('ul');
	tocul.id=tocListId;
	var tocli=document.createElement('li');	
	var tocnestul=document.createElement('ul');
	var toca=ds_link(tocLinkText);
	var toca=ds_link(tocLinkText);
	toca.onclick=function(){
		var nul=this.parentNode.getElementsByTagName('ul')[0];
		if(nul.className){nul.className='';} else {nul.className=hideClass; news.focus();}
		return false;
	}
	tocli.appendChild(toca);
	tocli.appendChild(tocnestul);
	tocul.appendChild(tocli);
	tocnestul.className=hideClass;
	document.getElementById(footerId).insertBefore(tocul,document.getElementById(footerId).firstChild);

	// Loop through DIVs, and identify slides
	var divs=document.getElementsByTagName('div');
	var c=1;
	var slides=new Array();
	for(var i=1;i<divs.length;i++){
		if(new RegExp('\\b'+slideClass+'\\b').test(divs[i].className)){
			var hl=divs[i].getElementsByTagName('h2')[0];
			if(!hl){continue;}
			slides[c]=divs[i];
			c++;
			var hl=divs[i].getElementsByTagName('h2')[0].firstChild.nodeValue;
			if(oldhl && oldhl==hl){continue;}
			var newli=document.createElement('li');
			var newa=ds_link(hl);
			newa.c=c-1;
			newa.onclick=function(){showslide(this.c); this.parentNode.parentNode.className=hideClass; return false;}
			newli.appendChild(newa);
			tocnestul.appendChild(newli);
			var oldhl=hl;
		}
	}

	// Add closing link to TOC
	var tocli=document.createElement('li');	
	var toca=ds_link(tocCloseText);
	toca.onclick=function(){tocnestul.className=hideClass; news.focus(); return false;}
	tocli.appendChild(toca);
	tocli.id=closeTocId;
	tocnestul.appendChild(tocli);

	// Create form with the select box
	var newf=document.createElement('form');
	newf.id=navigationForm;
	var news=document.createElement('select');
	news.size=10;

	// Loop through all slides
	for(var i=1;i<slides.length;i++){
		// Add the option with the title to the select box
		var newo=document.createElement('option');
		newo.appendChild(document.createTextNode(slides[i].getElementsByTagName('h2')[0].firstChild.nodeValue));
		news.appendChild(newo);
		newf.appendChild(news);
		document.getElementById(boundaryId).appendChild(newf);
		news.onchange=function(){showslide(this.selectedIndex+1);}

		// Counter, previous/next list
		var newul=document.createElement('ul');
		newul.className=counterClass;

		// Number
		var newli=document.createElement('li');
		newli.className='number';
		var tmpText=counterText.replace('_x_',i);
		var tmpText=tmpText.replace('_y_',(slides.length-1));
		newli.appendChild(document.createTextNode(tmpText));
		newul.appendChild(newli);

		// Previous
		if(i>1){
			var newli=document.createElement('li');
			var newa=ds_link(prevSlideText);
			newa.i=i-1;
			newa.onclick=function(){showslide(this.i); return false;}
			newli.appendChild(newa);
			newul.appendChild(newli);
		}
		if(i<=1){
			var newli=document.createElement('li');
			var newa=fake_link(prevSlideText);
			newli.appendChild(newa);
			newul.appendChild(newli);
		}

		// Next
		if(i<slides.length-1){
			var newli=document.createElement('li');
			var newa=ds_link(nextSlideText);
			newa.i=i+1;
			newa.onclick=function(){showslide(this.i); return false;}
			newli.appendChild(newa);
			newul.appendChild(newli);
		}
		if(i>=slides.length-1){
			var newli=document.createElement('li');
			var newa=fake_link(nextSlideText);
			newli.appendChild(newa);
			newul.appendChild(newli);
		}
		slides[i].appendChild(newul);
	}

	// check if there is a slide chosen on the URL and set it accordingly
	var cid=window.location.toString().match(/#slide(.+)/);
	if (cid && cid[1]){cid=cid[1];}
	var startslide=cid?cid:1;

	// add class to boundary indicating JavaScript is available
	document.getElementById(boundaryId).className=jsIndicatorClass;
	newf.className=hideClass;
	showslide(startslide);
	var mainheading=document.getElementsByTagName('h1')[0];
	var headcontent=mainheading.firstChild.nodeValue;
	mainheading.className=hideClass;
	var newspan=document.createElement('span');
	newspan.appendChild(document.createTextNode(titleAdd+headcontent));
	document.getElementById('footer').appendChild(newspan);

	/* tool methods */
	// creates new link
	function ds_link(t){
		var tmp=document.createElement('a');
		tmp.appendChild(document.createTextNode(t))
		tmp.href='#';
		return tmp;
	}
	function fake_link(t){
		var tmp=document.createElement('span');
		tmp.appendChild(document.createTextNode(t))
		return tmp;
	}
	// show the current slide, set the select focus
	function showslide(o){
		news.selectedIndex=o-1;
		for(var i=1;i<slides.length;i++){slides[i].className=hideClass;}
		if(slides[o]){slides[o].className=slideClass;}
		news.focus();
	}
}