var oldobj = null;

	function toggleDatelist ( id ) {
		var _table = document.getElementById(id + "_dates")
		if (oldobj != null && oldobj != _table) {
			oldobj.className = "hidden";
			oldobj = null;
		}
		_table.className = _table.className == "hidden" ? "" : "hidden";
		if (_table.className != "hidden") {
			_table.focus();
			oldobj = _table;
		}
	}
	
	function showExtendedForm ( acceptbutton ) {
		var button = document.getElementById("accept-button");
		var element = document.getElementById("extended-reservation");
		if (button) {
			button.className = (acceptbutton) ? "" : "hidden";
		}
		if (element.className == "hidden") {
			element.className = "";
		}
	}
	
	function checkCommentField ( ) {
		if (document.getElementById("userdefined-comment").value == "") {
			if (document.getElementById("extended-reservation").className == "hidden") {
				return false;
			}
			alert("Kommentarfeld muss ausgefüllt werden.");
			return false;
		}
		return true;
	}