var open_contents = new Array;
var all_contents = new Array;
var count = 0;
var cid;
var dur = 0.2;

function togglecontent(content_id) {
	if(!open_contents[content_id]) activatecontent(content_id);
	else deactivatecontent(content_id);

	open_contents.each(function(item){
    	if(item && item != content_id) deactivatecontent(item);
	});
}

function activatecontent(content_id) {
		open_contents[content_id] = content_id;
		$('img_'+content_id).src = '/images/basic/buttons/bigbutton_activ.gif';
		Effect.BlindDown('content_'+content_id, {duration: dur});
}

function deactivatecontent(content_id) {
		open_contents[content_id] = false;
		$('img_'+content_id).src = '/images/basic/buttons/bigbutton_inactiv.gif';
		Effect.BlindUp('content_'+content_id, {duration: dur});
}

function next_content() {
		open_contents.each(function(item, index) {
			//weise cid den offenen content zu
			if(item) {
				cid = item;
			}
			
		});
		
		if(!cid) {
			//wenn cid nicht gesetzt, toggle den ersten content
			cid = all_contents[0];
			togglecontent(cid);
		}
		else {
			all_contents.each(function(item) {
				if(item == cid) {
					//determine the next content in order, if last, take the first one 
					next = all_contents.indexOf(cid)+1;
					
					
					if(next == all_contents.length) {
						next = 0;
					}
					
					togglecontent(all_contents[next]);
				}
			});
		}
	return false;
}