//Author: Morris Ng

if (vmPlN=="MlIllSlN"){vmDt=new Date(); vmYr=vmDt.getYear(); vmMn=vmDt.getMonth()+1; vmDy=vmDt.getDate(); vmYrRoot=1900; if(vmYr>=2000){vmYrRoot=0;} vmYrWhole=vmYrRoot+vmYr; vmYrPrior=vmYrWhole-1; vmWriDt=vmYrWhole+"-"+vmMn+"-"+vmDy;}
function fmGetDate(){document.nmFrmCalc.nmTxYrBeg.value=vmYrPrior; document.nmFrmCalc.nmTxMnBeg.value=vmMn; document.nmFrmCalc.nmTxDyBeg.value=25; document.nmFrmCalc.nmTxYrEnd.value=vmYrWhole; document.nmFrmCalc.nmTxMnEnd.value=vmMn; document.nmFrmCalc.nmTxDyEnd.value=vmDy;} 
function fmMsgFromTo(pm1){vmMsgFrom=" ... for example, "+vmYrPrior+" / "+vmMn+" / 25"; vmMsgTo=" ... for example, " +vmYrWhole+" / " +vmMn+" / "+vmDy; if (pm1=="F"){document.writeln("<font id=V8 color=white><b>FROM</b> "+vmMsgFrom+"</font>");} if (pm1=="T"){document.writeln("<font id=V8 color=white><b>TO</b> "+vmMsgTo+"</font>");}}
function fmChkInput(){vmYrBegInp=document.nmFrmCalc.nmTxYrBeg.value; if (!((vmYrBegInp>1850)&&(vmYrBegInp<2123))) {fmInitEmpty(); alert("Year input in \"FROM\" box is invalid. Please try again.    "); document.nmFrmCalc.nmTxYrBeg.focus(); document.nmFrmCalc.nmTxYrBeg.select(); return false;} 
vmMnBegInp=document.nmFrmCalc.nmTxMnBeg.value; if (vmMnBegInp.indexOf(".")>=0) {fmInitEmpty(); alert("Month input in \"FROM\" box is invalid. Please try again.    "); document.nmFrmCalc.nmTxMnBeg.focus(); document.nmFrmCalc.nmTxMnBeg.select(); return false;} if (!((vmMnBegInp>0)&&(vmMnBegInp<13))) {fmInitEmpty(); alert("Month input in \"FROM\" box is invalid. Please try again.    "); document.nmFrmCalc.nmTxMnBeg.focus(); document.nmFrmCalc.nmTxMnBeg.select(); return false;} 
vmDyBegInp=document.nmFrmCalc.nmTxDyBeg.value; if (vmDyBegInp.indexOf(".")>=0) {fmInitEmpty(); alert("Day input in \"FROM\" box is invalid. Please try again.    "); document.nmFrmCalc.nmTxDyBeg.focus(); document.nmFrmCalc.nmTxDyBeg.select(); return false;} if (!((vmDyBegInp>0)&&(vmDyBegInp<32))) {fmInitEmpty(); alert("Day input in \"FROM\" box is invalid. Please try again.    "); document.nmFrmCalc.nmTxDyBeg.focus(); document.nmFrmCalc.nmTxDyBeg.select(); return false;} if ((vmDyBegInp==31)&&((vmMnBegInp==4)||(vmMnBegInp==6)||(vmMnBegInp==9)||(vmMnBegInp==11))){fmInitEmpty(); alert("Maximum number of days in April, June, September, and November is 30.    "); document.nmFrmCalc.nmTxDyBeg.focus(); document.nmFrmCalc.nmTxDyBeg.select(); return false;}
vmYrBegDivParse=parseInt(vmYrBegInp/4); vmYrBegDivEven=vmYrBegInp/4; vmYrBegDivTF="unequal"; if (vmYrBegDivParse==vmYrBegDivEven) {vmYrBegDivTF="equal";} else {vmYrBegDivTF="unequal";} if ((vmMnBegInp==2)&&(vmDyBegInp>=30)&&(vmYrBegDivTF=="equal")){fmInitEmpty(); alert("Maximum number of days in February for a leap year is 29.    "); document.nmFrmCalc.nmTxDyBeg.focus(); document.nmFrmCalc.nmTxDyBeg.select(); return false;} 
if ((vmMnBegInp==2)&&(vmDyBegInp>=29)&&(vmYrBegDivTF=="unequal")){fmInitEmpty(); alert("Maximum number of days in February for a common year is 28.    "); document.nmFrmCalc.nmTxDyBeg.focus(); document.nmFrmCalc.nmTxDyBeg.select(); return false;}
vmYrEndInp=document.nmFrmCalc.nmTxYrEnd.value; if (!((vmYrEndInp>1850)&&(vmYrEndInp<2123))) {fmInitEmpty(); alert("Year input in \"TO\" box is invalid. Please try again.    "); document.nmFrmCalc.nmTxYrEnd.focus(); document.nmFrmCalc.nmTxYrEnd.select(); return false;} 
vmMnEndInp=document.nmFrmCalc.nmTxMnEnd.value; if (vmMnEndInp.indexOf(".")>=0) {fmInitEmpty(); alert("Month input in \"TO\" box is invalid. Please try again.    "); document.nmFrmCalc.nmTxMnEnd.focus(); document.nmFrmCalc.nmTxMnEnd.select(); return false;} if (!((vmMnEndInp>0)&&(vmMnEndInp<13))) {fmInitEmpty(); alert("Month input in \"TO\" box is invalid. Please try again.    "); document.nmFrmCalc.nmTxMnEnd.focus(); document.nmFrmCalc.nmTxMnEnd.select(); return false;}
vmDyEndInp=document.nmFrmCalc.nmTxDyEnd.value; if (vmDyEndInp.indexOf(".")>=0) {fmInitEmpty(); alert("Day input in \"TO\" box is invalid. Please try again.    "); document.nmFrmCalc.nmTxDyEnd.focus(); document.nmFrmCalc.nmTxDyEnd.select(); return false;} if (!((vmDyEndInp>0)&&(vmDyEndInp<32))) {fmInitEmpty(); alert("Day input in \"TO\" box is invalid. Please try again.    "); document.nmFrmCalc.nmTxDyEnd.focus(); document.nmFrmCalc.nmTxDyEnd.select(); return false;} if ((vmDyEndInp==31)&&((vmMnEndInp==4)||(vmMnEndInp==6)||(vmMnEndInp==9)||(vmMnEndInp==11))){fmInitEmpty(); alert("Maximum number of days in April, June, September, and November is 30.    "); document.nmFrmCalc.nmTxDyEnd.focus(); document.nmFrmCalc.nmTxDyEnd.select(); return false;} 
vmYrEndDivParse=parseInt(vmYrEndInp/4); vmYrEndDivEven=vmYrEndInp/4; vmYrEndDivTF="unequal"; if (vmYrEndDivParse == vmYrEndDivEven) {vmYrEndDivTF="equal";} else {vmYrEndDivTF="unequal";}
if ((vmMnEndInp==2)&&(vmDyEndInp>=30)&&(vmYrEndDivTF=="equal")){fmInitEmpty(); alert("Maximum number of days in February for a leap year is 29.    "); document.nmFrmCalc.nmTxDyEnd.focus(); document.nmFrmCalc.nmTxDyEnd.select(); return false;} if ((vmMnEndInp==2)&&(vmDyEndInp>=29)&&(vmYrEndDivTF=="unequal")){fmInitEmpty(); alert("Maximum number of days in February for a common year is 28.    "); document.nmFrmCalc.nmTxDyEnd.focus(); document.nmFrmCalc.nmTxDyEnd.select(); return false;} fmDoCalc();}