var intervalId = 0;
var timerId = 0;
var huidigeTab = 1;

function blogpagenumber(nummer,timerOn){

	
	var posts = getElementsByClassName(document, "div", "tabelement"); 
	for(var i=0; i<posts.length; i++){
		posts[i].style.display= "none";
	}
	
	var postsshow = getElementsByClassName(document, "div", "tabgroup"+nummer); 
	for(var i=0; i<postsshow.length; i++){
		postsshow[i].style.display= "inline";
	}
}

function startInterval(){
	intervalId = setInterval ( "volgendeTab()", 10000 );
}

function stopInterval(){
	clearInterval(intervalId);	
}

function volgendeTab(){
	huidigeTab++;
	nextTab = getElementsByClassName(document, "div", "tabgroup"+huidigeTab);
	if(huidigeTab >= 6 || nextTab.length == 0){huidigeTab = 1;}
	blogpagenumber(huidigeTab,false);
}

function vorigeTab(){
	huidigeTab--;
	
	if(huidigeTab == 0){
		for(var i=0; i<5;i++){
			nextTab = getElementsByClassName(document, "div", "tabgroup"+i);
			if(nextTab.length != 0){
				huidigeTab = i;
			}
		}
	}
	blogpagenumber(huidigeTab,false);
}
	
function getElementsByClassName(oElm, strTagName, oClassNames){
	var arrElements = (strTagName == "*" && oElm.all)? oElm.all : oElm.getElementsByTagName(strTagName);
	var arrReturnElements = new Array();
	var arrRegExpClassNames = new Array();
	if(typeof oClassNames == "object"){
		for(var i=0; i<oClassNames.length; i++){
			arrRegExpClassNames.push(new RegExp("(^|\\s)" + oClassNames[i].replace(/\-/g, "\\-") + "(\\s|$)"));
		}
	}
	else{
		arrRegExpClassNames.push(new RegExp("(^|\\s)" + oClassNames.replace(/\-/g, "\\-") + "(\\s|$)"));
	}
	var oElement;
	var bMatchesAll;
	for(var j=0; j<arrElements.length; j++){
		oElement = arrElements[j];
		bMatchesAll = true;
		for(var k=0; k<arrRegExpClassNames.length; k++){
			if(!arrRegExpClassNames[k].test(oElement.className)){
				bMatchesAll = false;
				break;
			}
		}
		if(bMatchesAll){
			arrReturnElements.push(oElement);
		}
	}
	return (arrReturnElements)
	}
	
	
function writeAddr() {
	// Build the address
	var i,a=writeAddr.arguments,addr="";
	addr += a[0]+"@";
	for( i=1; i<a.length; i++ ) {
		if( i>1 ) addr += ".";
		addr += a[i];
	}
	// Write html to the browser with the email address
	document.write("<a href=\"mailto:" 
		+ addr + "\">" + addr + "</a>");
}