/*
Author: Robert Hashemian
http://www.hashemian.com/

You can use this code in any manner so long as the author's
name, Web address and this disclaimer is kept intact.
********************************************************
Usage Sample:

<script language="JavaScript">
TargetDate = "12/31/2020 5:00 AM";
BackColor = "palegreen";
ForeColor = "navy";
CountActive = true;
CountStepper = -1;
LeadingZero = true;
DisplayFormat = "%%D%% Days, %%H%% Hours, %%M%% Minutes, %%S%% Seconds.";
FinishMessage = "It is finally here!";
</script>
<script language="JavaScript" src="http://scripts.hashemian.com/js/countdown.js"></script>
*/

function calcage(secs, num1, num2) {
  s = ((Math.floor(secs/num1))%num2).toString();
  if (LeadingZero && s.length < 2)
    s = "0" + s;
  return "<b>" + s + "</b>";
}

function CountBack(secs,SetTimeOutPeriod) {    
  if (secs < 0) {
    document.getElementById("count_box").innerHTML = "<span id='cntdwn'></span><br /> ";
    document.getElementById("cntdwn").innerHTML = FinishMessage;
    return;
  }
      
  DisplayStr = DisplayFormat.replace(/%%D%%/g, calcage(secs,86400,100000));
  DisplayStr = DisplayStr.replace(/%%H%%/g, calcage(secs,3600,24));
  DisplayStr = DisplayStr.replace(/%%M%%/g, calcage(secs,60,60));
  DisplayStr = DisplayStr.replace(/%%S%%/g, calcage(secs,1,60));     
  document.getElementById("cntdwn").innerHTML = DisplayStr;
  if (CountActive)
    setTimeout("CountBack(" + (secs+CountStepper) + "," + SetTimeOutPeriod + ")", SetTimeOutPeriod);       
}

function start_clock(){ 
	if (typeof(TargetDate)=="undefined")
	  TargetDate = "12/31/2020 5:00 AM";
	if (typeof(DisplayFormat)=="undefined")
	  DisplayFormat = "%%D%% Days, %%H%% Hours, %%M%% Minutes, %%S%% Seconds.";
	if (typeof(CountActive)=="undefined")
	  CountActive = true;
	if (typeof(FinishMessage)=="undefined")
	  FinishMessage = "";
	if (typeof(CountStepper)!="number")
	  CountStepper = -1;
	if (typeof(LeadingZero)=="undefined")
	  LeadingZero = true;


	CountStepper = Math.ceil(CountStepper);
	if (CountStepper == 0)
	  CountActive = false;
	var SetTimeOutPeriod = (Math.abs(CountStepper)-1)*1000 + 990;
	var dthen = new Date(TargetDate);
	var dnow = new Date();
	if(CountStepper>0)
	  ddiff = new Date(dnow-dthen);
	else
	  ddiff = new Date(dthen-dnow);
	gsecs = Math.floor(ddiff.valueOf()/1000);     
	CountBack(gsecs,SetTimeOutPeriod);
} 

function addLoadEvent(func) {
  var oldonload = window.onload;
  if (typeof window.onload != 'function') {
    window.onload = func;
  } else {
    window.onload = function() {
      if (oldonload) {
        oldonload();
      }
      func();
    }
  }
}   

addLoadEvent(start_clock);