function isLeapYear (year) {
  return ((year % 4) == 0) && (((year % 100) != 0) || ((year % 400) == 0))
}

function getDaysInMonth(year, month) 
{
   month--;   
   var daysInMonth = new Array (31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31);
   var days=daysInMonth[month];
   if ((month == 1) && isLeapYear(year))
    days++;   
   return days;
}

function setDaysInMonth(d,targetId)
{
    var days=document.getElementById(targetId);     
    if (!days)
        return;
    var s = d.split('/');     
    if(s.length!=3)
        return;             
    var selIdx = days.selectedIndex;
    var n=days.options.length;    
    for(i=0;i<n;i++)
        days.remove(0);     
    for(i=1;i<=getDaysInMonth(s[2],s[1]);i++)
    { 
        var opt = new Option(i, i); 
        days.options.add(opt);        
        //var opt = document.createElement('OPTION');         
        //opt.innerText = i; 
        //opt.value = i; 
        //days.options.add(opt);        
    }
    days.selectedIndex = (selIdx>days.options.length-1)?days.options.length-1:selIdx;    
}

function setCalendarDatе(behId,tdId,e1Id,e2Id)
{	
    var beh=$find(behId);
	var e1=document.getElementById(e1Id);     	
	var e2=document.getElementById(e2Id);     	
	var tb=document.getElementById(tdId);	
    if (!beh || !e1 || !e2 || !tb)
        return;
    var d = tb.value; 
    var dd=d.split("/");  
    if(dd.length!=3)
		return;	

    var ok=false;		
	for (i=	0;i<e2.options.length;i++)
	{
	    if(e2.options[i].value=='/'+dd[1]+'/'+dd[2])
	    {
	        e2.value='/'+dd[1]+'/'+dd[2];
	        setDaysInMonth(e1.value+e2.value,e1Id);
	        for (j=0;j<e1.options.length;j++)
	        {
	            if(e1.options[j].value==dd[0])
	            {	                
	                e1.value=dd[0];	                
	                ok=true;
	            }
	        }
	        break;
	    }
	}
	    
	if(!ok)	
	{
	    tb.value=e1.value+e2.value;		    
	    dd=tb.value.split('/');
	    var dt=new Date();	
	    dt.setFullYear(dd[2],dd[1]-1,dd[0]);
	    beh._selectedDate = dt;
	}		
}

function setDate(behId,e1Id,e2Id)
{
    var beh=$find(behId);
    var e1=document.getElementById(e1Id);     	
	var e2=document.getElementById(e2Id);     		
    if (!beh || !e1 || !e2)
        return;   
    var tb = e1.value+e2.value;		    
	dd=tb.split('/');
	var dt=new Date();	
	dt.setFullYear(dd[2],dd[1]-1,dd[0]);
	beh._selectedDate = dt;			
}

function calHide(behId)
{
    var beh=$find(behId);    
    if (!beh)
        return;   
    beh.hide();
}