function addOfferte(id) {
	if(offerte_count>2) { 
		alert('U kunt maximaal drie vestigingen selecteren');
		return;
	}
	var div = 'vest_' + id;
	document.getElementById(div).innerHTML='- Offerte';
	document.getElementById(div).className='button_selected';
	document.getElementById(div).attributes['onclick'].value='delOfferte(' + id + '); return false;';
	offerte_count++;
	
	try {
		xmlhttp = new XMLHttpRequest();
		xmlhttp.open("GET", "http://" + document.domain + "/offerte/?mode=add&id=" + id,true);
		xmlhttp.send(null);
	} catch (e) {
	}	
}

function delOfferte(id) {
	var div = 'vest_' + id;
	document.getElementById(div).innerHTML='+ Offerte';
	document.getElementById(div).className='button';
	document.getElementById(div).attributes['onclick'].value='addOfferte(' + id + '); return false;';
	offerte_count--;
	try {
		xmlhttp = new XMLHttpRequest();
		xmlhttp.open("GET", "http://" + document.domain + "/offerte/?mode=del&id=" + id,true);
		xmlhttp.send(null);
	} catch (e) {
	}	
}

function checkOfferte() {
	if(offerte_count>2) { 
		alert('U kunt maximaal drie vestigingen selecteren');
		return false;
	}
	return true;
}