function show_kalender(arrival) {
	if(document.getElementById('kalender').style.display == 'none'){
		ajax('/kalender.php?' + arrival + '=true','kalender_content');
		document.getElementById('kalender').style.display = '';
	}else{
		document.getElementById('kalender').style.display = 'none';
	}
}
function move_kalender(Ereignis){
    document.getElementById("kalender").style.margin = Ereignis.clientX + "px " + (Ereignis.clientY) + "px";
}
function set_arrival(date){
	document.booking.arrival.value = date;
	document.getElementById('kalender').style.display = 'none';
}
function set_departure(date){
	document.booking.departure.value = date;
	document.getElementById('kalender').style.display = 'none';
}
function ajax(dateiname,divname) {
	var req = 0;
	//Request-Objekt erzeugen
	try {
		req = new XMLHttpRequest();
	}
	catch(ms) {
		try {
			req = new ActiveXObject("Msxml2.XMLHTTP");
		}
		catch(nonms) {
			try {
				req = new ActiveXObject("Microsoft.XMLHTTP");
			}
			catch(failed) {
				req = null;
			}
		}
	}
	if(req == null)
	alert("Error creating request Object.");

	//GET-Request senden
	req.open("GET", dateiname, true);

	//Status prüfen und anonyme Funktion erzeugen
	req.onreadystatechange = function() {
		switch(req.readyState) {
			case 1:
			document.getElementById(divname).innerHTML = '<span style="align:center;"><img src="images/loader.gif" alt="L&auml;dt..."></span>';
			case 4:
			if(req.status != 200) {
				alert("Fehler" + req.status);
			} else {
				//div leeren
				if(document.getElementById(divname).innerHTML != '') document.getElementById(divname).innerHTML = '';
				//Dateiinhalt in div schreiben
				document.getElementById(divname).innerHTML = req.responseText;
			}
			break;
			default:
			return false;
			break;
		}
	};
	req.setRequestHeader("Content-Type", "application/x-www-form-urlencoded");
	req.send(null);
}