function isEmpty(field)
{
	var value = trim(field.value);
	if(!value.length)
	{
		error(field, "Bitte füllen Sie dieses Feld aus.");
		return false;
	}
	else
	{
		success(field);
		return true;
	}
}

function hasPLZ(field)
{
	var result = /[0-9]{5}/.test(field.value);
	if(result)
		success(field);
	else
		error(field, "Dieses Feld enthält keine Postleitzahl!");
	
	return result;
}

function isValidAddress(field)
{
	var result = /\w{3,}@\w{3,}\.{1}[A-Za-z]{2,4}/.test(field.value);
	if(result)
		success(field);
	else
		error(field, "Dieses Feld enthält keine gültige Adresse!");
	
	return result;
}

function submitForm()
{
	var ok = true;
	
	var name = document.getElementById('name');	
	var strasse = document.getElementById('strasse');
	var plzort = document.getElementById('plzort');
	var email = document.getElementById('email');
	var telefon = document.getElementById('telefon');
	
	ok = isEmpty(name) && ok;
	ok = isEmpty(strasse)  && ok;
	ok = isEmpty(plzort)  && ok;
	ok = isEmpty(email) && ok;
	ok = isEmpty(telefon) && ok;
	//ok = isValidAddress(email) && ok;
	//ok = hasPLZ(plzort) && ok;
	
	if(ok)
	{
		document.getElementById('contactform').submit();
	}
}

function error(field, message)
{
	field.className += " validation_error";
	
	if(message)
		field.title = message;
	else
		field.title = "Dieses Feld enthält ungültige Eingaben";
}

function success(field)
{
	field.className = field.className.replace("validation_error", "");
	field.title = "";
}

function trim(str, chars) {
    return ltrim(rtrim(str, chars), chars);
}

function ltrim(str, chars) {
    chars = chars || "\\s";
    return str.replace(new RegExp("^[" + chars + "]+", "g"), "");
}

function rtrim(str, chars) {
    chars = chars || "\\s";
    return str.replace(new RegExp("[" + chars + "]+$", "g"), "");
}