isIE = (document.all ? true : false);
isDOM = (document.getElementById ? true : false);

// Start with a calendar for today.
today = new getToday();

// Initialize arrays.
var months = new Array("Jan", "Feb", "Mar", "Apr", "May", "Jun", "Jul","Aug", "Sep", "Oct", "Nov", "Dec");
var daysInMonth = new Array(31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31);
var displayMonth = new Date().getMonth();
var displayYear = new Date().getFullYear();
var displayDivName;
var displayElement;
var hiddenElement;
var currentDateValue;

var colour_bg = "#F7FAFB";
var colour_link = "#0180B3";
var colour_monthyear = "#005982";
var colour_selectedtext = "#FFFFFF";
var colour_selectedbg = "#005982"


function getDays(month, year) {
   // Test for leap year when February is selected.
   if (1 == month)
      return ((0 == year % 4) && (0 != (year % 100))) ||
         (0 == year % 400) ? 29 : 28;
   else
      return daysInMonth[month];
}

function getToday() {
   // Generate today's date.   
   this.now = new Date();
   this.year = this.now.getFullYear();
   this.month = this.now.getMonth();
   this.day = this.now.getDate();
}

function getDate(thedate) {
   
   this.now = new Date(thedate); 
   
   this.year = this.now.getFullYear();
   this.month = this.now.getMonth();
   this.day = this.now.getDate();
}


function newCalendar(eltName,attachedElement,attachedHiddenElement) {
   if (attachedElement) {
      if (displayDivName && displayDivName != eltName) hideElement(displayDivName);
      displayElement = attachedElement;
      //hiddenElement = attachedHiddenElement;
   }
	
	   displayDivName = eltName;
       //today = new getToday();
		
		if (currentDateValue != '') {	
			today = new getDate(currentDateValue);
		} else {
			today = new getToday();
		}			
		       
       var parseYear = parseInt(displayYear + '');
       var newCal = new Date(parseYear,displayMonth,1);
       var day = -1;
       var startDayOfWeek = newCal.getDay();
       if ((today.year == newCal.getFullYear()) &&
             (today.month == newCal.getMonth()))
   {
          day = today.day;
       }
       var intDaysInMonth =
          getDays(newCal.getMonth(), newCal.getFullYear());
			var daysGrid = makeDaysGrid(startDayOfWeek,day,intDaysInMonth,newCal,eltName)              
   if (isIE) {
      var elt = document.all[eltName];
      elt.innerHTML = daysGrid;
       } else if (isDOM) {
      var elt = document.getElementById(eltName);
      elt.innerHTML = daysGrid;
   } else {
      var elt = document.layers[eltName].document;
      elt.open();
      elt.write(daysGrid);
      elt.close();
   }
}

function incMonth(delta,eltName) {
  displayMonth += delta;
  if (displayMonth >= 12) {
    displayMonth = 0;
    incYear(1,eltName);
  } else if (displayMonth <= -1) {
    displayMonth = 11;
    incYear(-1,eltName);
  } else {
    newCalendar(eltName);
  }
}

function incYear(delta,eltName) {
  displayYear = parseInt(displayYear + '') + delta;
  newCalendar(eltName);
}

function makeDaysGrid(startDay,day,intDaysInMonth,newCal,eltName) {
   var daysGrid;
   var month = newCal.getMonth();
   var year = newCal.getFullYear();
   var isThisYear = (year == new Date().getFullYear());
   var isThisMonth = (day > -1)
   daysGrid = '<table border=1 cellspacing=0 cellpadding=2><tr><td bgcolor='+colour_bg+ ' nowrap>';
   daysGrid += '<font face="arial,helvetica,sans-serif" size=2>';   
   daysGrid += '<a href="javascript:incMonth(-1,\'' + eltName + '\')">&laquo; </a>';

   daysGrid += '<b>';
   if (isThisMonth) { daysGrid += '<font color="' + colour_monthyear + '">' + months[month] + '</font>'; }
   else { daysGrid += months[month]; }
   daysGrid += '</b>';

   daysGrid += '<a href="javascript:incMonth(1,\'' + eltName + '\')"> &raquo;</a>';
   daysGrid += '&nbsp;&nbsp;&nbsp;';
   daysGrid += '<a href="javascript:incYear(-1,\'' + eltName + '\')">&laquo; </a>';

   daysGrid += '<b>';
   if (isThisYear) { daysGrid += '<font color="' + colour_monthyear + '">' + year + '</font>'; }
   else { daysGrid += ''+year; }
   daysGrid += '</b>';

   daysGrid += '<a href="javascript:incYear(1,\'' + eltName + '\')"> &raquo;</a>';
   daysGrid += '&nbsp;&nbsp;';
   daysGrid += '<a href="javascript:hideElement(\'' + eltName + '\')">Cancel</a>';
   daysGrid += '<br>';
   daysGrid += '&nbsp;Su Mo Tu We Th Fr Sa&nbsp;<br>&nbsp;';
   var dayOfMonthOfFirstSunday = (7 - startDay + 1);
   for (var intWeek = 0; intWeek < 6; intWeek++) {
      var dayOfMonth;
      for (var intDay = 0; intDay < 7; intDay++) {
        dayOfMonth = (intWeek * 7) + intDay + dayOfMonthOfFirstSunday - 7;
    if (dayOfMonth <= 0) {
          daysGrid += "&nbsp;&nbsp; ";
    } else if (dayOfMonth <= intDaysInMonth) {
      var color = colour_link;
      var bgcolor = colour_bg;
      if (day > 0 && day == dayOfMonth) { 
		color=colour_selectedtext;
		bgcolor = colour_selectedbg;
	  }
      daysGrid += '<a href="javascript:setDay(';
      daysGrid += dayOfMonth + ',\'' + eltName + '\')" '
      daysGrid += 'style="color:' + color + ';background-color:' + bgcolor + '">';
      var dayString = dayOfMonth + "</a> ";
      if (dayString.length == 6) dayString = '0' + dayString;
      daysGrid += dayString;
    }
      }
      if (dayOfMonth < intDaysInMonth) daysGrid += "<br>&nbsp;";
   }
   return daysGrid + "</font></td></tr></table>";
}

function setDay(day,eltName) {
  // DD/MM/YYYY format for displaying
  var tmpD;
  var tmpM;
  if (day < 10) {tmpD = '0' + day; } 
  else {tmpD = day;  }
  if (displayMonth+1 < 10) { tmpM = '0' + (displayMonth+1); }
  else { tmpM = displayMonth+1; }
  
  displayElement.value = tmpD + "/" + tmpM + "/" + displayYear;
  
  // YYYY/MM/DD format for storing
  //hiddenElement.value = displayYear + "/" + (displayMonth + 1) + "/" + day;
  hideElement(eltName);
}