function moderate(){ok1=document.getElementById('tb_checkin').value!="";ok2=document.getElementById('tb_checkout').value!="";if(!ok1){alert("Bitte geben Sie ein Anreise- und Abreise-Datum ein!");document.getElementById('tb_checkin').focus();return ok1;}
if(!ok2){alert("Bitte geben Sie ein Anreise- und Abreise-Datum ein!");document.getElementById('tb_checkout').focus();return ok2;}
return ok1&&ok2;}
function parseDateFromString(date){var re=/^([0-9]{1,2})\.([0-9]{1,2})\.([0-9]{4})$/i;var stDate="";if(date!=""){if(re.test(date)){day=RegExp.$1;day=""+day;if(day.length<2){day="0"+day;}
month=RegExp.$2;month=""+month;if(month.length<2){month="0"+month;}
year=parseInt(RegExp.$3);year=""+year;if(year.length<3){year="20"+year;}
stDate=month+"/"+day+"/"+year;}}
return stDate;}
function dateSimpleFormat(date,format){var day=date.getDate();day=""+day;if(day.length<2){day="0"+day;}
var month=date.getMonth()+1;month=""+month;if(month.length<2){month="0"+month;}
var year=date.getFullYear();if(format=="dd.mm.yyyy"){return""+day+"."+month+"."+year;}
if(format=="dd/mm/yyyy"){return""+day+"/"+month+"/"+year;}
if(format=="mm/dd/yyyy"){return""+month+"/"+day+"/"+year;}}
function diffDate(nDate1,nDate2){var date1=new Date(nDate1);var date2=new Date(nDate2);var gap=date2.getTime()-date1.getTime();gap=Math.ceil(gap/(1000*60*60*24));return gap;}
function dateAddDays(date,days){var ret=new Date(date);ret.setDate(ret.getDate()+days);return ret;}
function onChangeDate(fieldBegin,fieldEnd,fieldNights){var d1=document.getElementById(fieldBegin).value;var d2=document.getElementById(fieldEnd).value;var currentDate=new Date();if(d1!=""){stDate1=parseDateFromString(d1);if(diffDate(currentDate,stDate1)<0){alert("Das Anreise-Datum kann nicht in der Vergangenheit liegen!");stDate1=dateSimpleFormat(currentDate,"mm/dd/yyyy");document.getElementById(fieldBegin).value=dateSimpleFormat(currentDate,"dd.mm.yyyy");}
if(diffDate(currentDate,stDate1)>300){alert('Buchungen können nur bis max 300 Tage im Voraus getätigt werden');stDate1=dateSimpleFormat(dateAddDays(currentDate,300),"mm/dd/yyyy");document.getElementById(fieldBegin).value=dateSimpleFormat(new Date(stDate1),"dd.mm.yyyy");}}
if(d2!=""){stDate2=parseDateFromString(d2);if(d1==""){stDate1=dateSimpleFormat(currentDate,"mm/dd/yyyy");document.getElementById(fieldBegin).value=dateSimpleFormat(new Date(stDate1),"dd.mm.yyyy");}
if(diffDate(stDate1,stDate2)<0){alert("Das Abreise-Datum kann nicht in der Vergangenheit liegen!");stDate2=dateSimpleFormat(dateAddDays(stDate1,1),"mm/dd/yyyy");document.getElementById(fieldEnd).value=dateSimpleFormat(new Date(stDate2),"dd.mm.yyyy");}}
if(d1!=""&&d2!=""){diffDays=diffDate(stDate1,stDate2);document.getElementById(fieldNights).value=diffDays;}}
function onChangeNights(fieldBegin,fieldNights,fieldEnd){var d1=document.getElementById(fieldBegin).value;var nt=document.getElementById(fieldNights).value;if(d1!=""){stDate1=parseDateFromString(d1);}
if(nt!=""){nights=parseInt(nt);if(nights>30){alert("Die maximale Aufenthaltsdauer betragt 30 Tage");nights=30;document.getElementById(fieldNights).value=nights;}}
document.getElementById(fieldEnd).value=dateSimpleFormat(dateAddDays(stDate1,nights),"dd.mm.yyyy");}