/*
822 Adaptation
Author: Robert Hashemian, Philip Reed
Original notice follows: 
********************************************************

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>";
}

/****
*   Adapting this callback mechanism to more than one relevant div has 
*   probably resulted in spaghetti code.   The upshot is, we need to pass
*   invocationCount because we want each callback to set to pertain only
*   to that div even after the count has incremented to something else.
*   countActive and timeOutPeriod are necessary here because they were globals
*   that got wrapped in a function.
***/
function CountBack(secs, invocationCount, countActive, timeOutPeriod) {
  if (secs < 0) {
    document.getElementById("cntdwn"+invocationCount).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"+invocationCount).innerHTML = DisplayStr;
  if (CountActive) {
    document.getElementById("debug822").innerHTML += 
        invocationCount;
        //("invocation "+invocationCount+"<br/>");
        
    setTimeout("CountBack(" + (secs+CountStepper) + ", " + 
        invocationCount + ", true, "+timeOutPeriod+")", timeOutPeriod);
  }
}

function putspan(backcolor, forecolor) {
 //By including countdownInvocations in the ID, we allow multiple invocations of the function 
 // to create multiple referenceable spans.
 document.write("<span id='cntdwn"+countdownInvocations+"' style='background-color:" + backcolor + 
                "; color:" + forecolor + "'></span>");
}

/*** TODO: Use named params so that we don't have to use all params all the time! **/
function displayCountdown(TargetDate, DisplayFormat, CountActive, FinishMessage, CountStepper, LeadingZero, BackColor, ForeColor)
{
    countdownInvocations++;
    if (typeof(BackColor)=="undefined")
      BackColor = "white";
    if (typeof(ForeColor)=="undefined")
      ForeColor= "black";
    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;
    putspan(BackColor, ForeColor);
    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, countdownInvocations, CountActive, SetTimeOutPeriod);
}