var months = new Array("January", "February", "March", "April", "May", "June", "July", "August", "September", "October", "November", "December");
function checkDate(fm) {
var tb = document.getElementById('certAction');
var yr = document.getElementById('certYr');
var mo = document.getElementById('certMo');  
var calc= document.getElementById('calc');
  calc.style.display="none";
  if (!validateFld(yr, mo)) return false;
  rs = buildTbl(5, mo.value, yr.value);
  calc.style.display="block";
  return false;
}
function buildTbl(yrs, mov, yrv) {
var tb = document.getElementById('certAction');
var even = false;
    if (tb.rows.length>0) {
        for (i=tb.rows.length-1; i>=0; i--) { tb.deleteRow(i); }
    }
    for (i=1; i<=yrs; i++) {
        var rs=tb.rows.length;
        tb.insertRow(rs);
        tb.rows[rs].insertCell(0);
        if (even) {
            tb.rows[rs].cells[0].appendChild(document.createTextNode("Recertify"));
            tb.rows[rs].className='even';
        } else tb.rows[rs].cells[0].appendChild(document.createTextNode("Renew"));
        tb.rows[rs].insertCell(1);
        tb.rows[rs].cells[1].appendChild(document.createTextNode(mov+" / "+(parseInt(yrv)+i)));
        even = !even;
    }
    return;
}
function validateFld(yr, mo) {
var yrv = yr.value;
var mov = mo.value;
var today = new Date();
var err = "";
var todaysYear = today.getFullYear();
var dt = mov+"/"+yrv;
var exp = /^((0[1-9])|(1[0-2]))\/(\d{4})/;

    if ((yrv.length==0)||(yrv.length<4)) { err='Please enter a 4 digit year.'; }
    if ((mov.length==0)||(mov.length<2)) { err='Please enter a 2 digit month.'; }
    if (todaysYear<parseInt(yrv)) { err='Please enter a valid year.'; }
    if (yrv<1995) { err='Please enter a year greater than 1995.'; }
    if (!exp.test(dt)) { err='Please enter a valid date.'};
    if (!err=="") { alert(err); mo.focus(); return false; }
    return true;
}

function autoTab(fm) {
  if (fm.certMo.value.length==2) {fm.certYr.focus();}
}
function certCalc() {
var out="";
  out='<p>Not sure when you need to <span class="bold">renew</span> or <span class="bold">recertify</span> your BMSC credential? Enter your certification date below to make sure you’re on track!</p>';
  out+='<form name="cert" id="cert" action="" method="GET" >';
  out+='<span class="bold">Certification Type:</span><br /><select>';
  out+='<option value="HCS-D">HCS-D</option><option value="SCP">SCP</option><option value="CCP-P">CCP-P</option><option value="ACS">ACS</option>';
  out+='</select><br style="clear:both;" /><br />';
  out+='<span class="bold">Date: (mm/yyyy)<br /></span><input type="text" maxlength="2" size="2" id="certMo" name="certMo" onkeyup="autoTab(this.form);" /> / <input type="text" maxlength="4" size="4" id="certYr" name="certYr" /><br style="clear:both;" />';
  out+='<br /><input value="Submit" type="button" onClick="checkDate(this.form);" /></form>';
  out+='<div id="calc" style="display:none;"><br />';
  out+='<p>The table below shows when you need to renew and recertify your credential.</p>';
  out+='<table><thead><tr><th>Action</th><th>Date</th></tr></thead>';
  out+='<tbody id="certAction"></tbody></table><br />';
  out+='<p class="bold">Ready to renew?</p><p><a href="pdf/BMSCRenewalApplication.pdf">Download your renewal application.</a></p>';
  out+='<p class="bold">Ready to recertify?</p><p><a href="pdf/BMSCgenregform.pdf">Download your recertification application.</a></p></div>';
  document.write(out);
}