function layout_img_toggle(element) {
	/* Konvention für Dateiname : image.gif -> over_image.gif */
	var image = element.src;
	var path = image.substr(0,image.lastIndexOf("/")+1);
	
	if (image.substr(image.lastIndexOf("/")+1,4) == "over") {
		element.src = path + image.substr(image.lastIndexOf("/")+6,image.length);
	} else {
		element.src = path + "over_" + (image.substr(image.lastIndexOf("/")+1,image.length));
	}
}

function layout_div_toggle(element) {
	if (element.className.slice(0,5) == "over_") {
		element.className = element.className.substring(5, element.className.length);
	} else {
		element.className = "over_" + element.className;
	}
}

function MM_preloadImages() { //v3.0
  var d=document; if(d.images){ if(!d.MM_p) d.MM_p=new Array();
    var i,j=d.MM_p.length,a=MM_preloadImages.arguments; for(i=0; i<a.length; i++)
    if (a[i].indexOf("#")!=0){ d.MM_p[j]=new Image; d.MM_p[j++].src=a[i];}}
}

function showPopup(url) {
    winWidth=800;
    winHeight=410;
	
    breite = screen.width - 0;
    hoehe = screen.height - 0;
    
    px = breite/2-(winWidth/2)-5;
    py = hoehe/2-(winHeight/2)-5;
  
    wndProps = "top="+py+",left="+px+",width="+winWidth+",height="+winHeight+",dependant=yes,scrollbars=no,resizable=no";
    myWnd = window.open(url,"Popup",wndProps);	
}

function ColorAndFocus(field) {
	field.style.backgroundColor = "#DEDEAE";
	field.focus();
}

function checkEmail(email) {
	var proto  = "(mailto:)?";
	var usr    = "([a-zA-Z0-9][a-zA-Z0-9_.-]*|\"([^\\\\\x80-\xff\015\012\"]|\\\\[^\x80-\xff])+\")";
	var domain = "([a-zA-Z0-9][a-zA-Z0-9._-]*\\.)*[a-zA-Z0-9][a-zA-Z0-9._-]*\\.[a-zA-Z]{2,5}";
	var regex  = "^" + proto + "?" + usr + "\@" + domain + "$";

	var rgx    = new RegExp(regex);
	return rgx.exec(email) ? true : false;
}

function checkComment(form) {
	if (!form.elements["c_name"].value) {
		alert("Bitte geben Sie Ihren Namen an.");
		ColorAndFocus(form.elements["c_name"]);
		return false;
	}
	if (!form.elements["c_email"].value) {
		alert("Bitte geben Sie Ihrer Email an.");
		ColorAndFocus(form.elements["c_email"]);
		return false;
	}
	if (!checkEmail(form.elements["c_email"].value)) {
		alert("Bitte geben Sie eine gültige Email an.");
		ColorAndFocus(form.elements["c_email"]);
		return false;
	}
	if (!form.elements["c_comment"].value) {
		alert("Bitte tragen Sie einen Kommentar ein.");
		ColorAndFocus(form.elements["c_comment"]);
		return false;
	}
	return true;
}

function checkResponder(form) {
	if (!form.elements["f_userName"].value) {
		alert("Bitte geben Sie Ihren Namen an.");
		ColorAndFocus(form.elements["f_userName"]);
		return false;
	}
	if (!checkEmail(form.elements["f_userEmail"].value)) {
		alert("Bitte geben Sie Ihrer Email an.");
		ColorAndFocus(form.elements["f_userEmail"]);
		return false;
	}
	if (!form.elements["f_userMessage"].value) {
		alert("Bitte geben Sie eine gültige Message an.");
		ColorAndFocus(form.elements["f_userMessage"]);
		return false;
	}
	return true;
}

function toggle(id) {
	var elem = document.getElementById(id);
	if (!elem) return;
	if (elem.className.slice(0,7) == "hidden_") {
		elem.className = elem.className.substring(7, elem.className.length);
	} else {
		elem.className = "hidden_" + elem.className;
	}
}