/*
	Client side scripts required to support the date selection dropdowns
	Author: Michael McLain
	Release: 1.0
	Note: These scripts must be placed prior to calling the GenDateDropDown subroutine
	Return number of days in a month
	Parameters: lnMonth: month (1-12)
	            lnYear:  year => 1970
	*/
	var MonthDays = new Array(31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31);

	function daysinmonth(lnMonth,lnYear) {
		thisMonth = lnMonth - 1;
		thisYear = lnYear
		if (thisYear == '') { thisYear = 1900; }
		/*
		var dt1, cmn1, cmn2, dtt, lflag, dycnt, lmn
		lmn = lnMonth-1
		dt1 = new Date(lnYear,lmn,1)
		cmn1 = dt1.getMonth()
		dtt=dt1.getTime()+2332800000
		lflag = true
		dycnt=28
		while (lflag) {
		   dtt = dtt + 86400000
		   dt1.setTime(dtt)
		   cmn2 = dt1.getMonth()
		   if (cmn1!=cmn2) {
		      lflag = false }
		   else {dycnt = dycnt + 1; alert(cmn1 + ' ' + cmn2 + ' ' + dycnt);}}
		if (dycnt > 31) {dycnt = 31}
		return dycnt
		*/
		
		return ((thisMonth == 1) && ((thisYear % 400 == 0) || ((thisYear % 4 == 0) && (thisYear % 100 != 0)))) ? 29 : MonthDays[thisMonth];
	}

	function setdays(sobjname, datemode){
		var dobj = document.getElementById(sobjname + "d")//eval(sobjname + "d")
		var mobj = document.getElementById(sobjname + "m")//eval(sobjname + "m")
		var yobj = document.getElementById(sobjname + "y")//eval(sobjname + "y")
		var hobj = document.getElementById(sobjname)//eval(sobjname)
		var monthdays = daysinmonth(mobj.options[mobj.selectedIndex].value,yobj.options[yobj.selectedIndex].value)
		if (monthdays == undefined) { monthdays = 0; }
		//var selectdays = dobj.length
		var curdy = dobj.options[dobj.selectedIndex].value
		if (curdy.length==1) {curdy = "0"+curdy}
		var curmn = mobj.options[mobj.selectedIndex].value
		if (curmn.length==1) {curmn = "0"+curmn}
		var curyr = yobj.options[yobj.selectedIndex].value
		for ( var i=0; i<=31; i++ ) {
			if (i==0) { 
				dobj.options[i] = new Option('Select',i); 
			}
			else {
				if (i <= monthdays) {
					dobj.options[i] = new Option(i,i);
					if (curdy == i) {
						dobj.options[i].selected = true;
					}
				}
				else {
					break;
				}
			}
		}
		
		for (var j=dobj.length; j>monthdays; j--) {
			dobj.options[i] = null;
		}
		
		/*
		if (selectdays > monthdays) {
		   for (var dlp=selectdays; dlp > monthdays; dlp--) {
				dobj.options[dlp-1] = null }}
		else if (monthdays > selectdays) {
		   for (var dlp=selectdays; dlp < monthdays; dlp++) {
		       dobj.options[dlp] = new Option(dlp+1,dlp+1) }}
		*/
		if (curdy > monthdays) {
		   //dobj.options[monthdays-1].selected = true
		   dobj.options[monthdays].selected = true
		   curdy = monthdays }
		if (datemode==1) {
		   var curdate = curmn+"/"+curdy+"/"+curyr }
		else if (datemode==2) {
		   var curdate = curdy+"/"+curmn+"/"+curyr }
		else if (datemode==3) {
		   var curdate = curyr+curmn+curdy }
		else if (datemode==4) {
		   var cdate = new Date(curyr,curmn-1,curdy)
		   var curdate = cdate.toGMTString() }
		hobj.value = curdate
	}