function positionInfo(object) {

  var p_elm = object;

  this.getElementLeft = getElementLeft;
  function getElementLeft() {
    var x = 0;
    var elm;
    if(typeof(p_elm) == "object"){
      elm = p_elm;
    } else {
      elm = document.getElementById(p_elm);
    }
    while (elm != null) {
      x+= elm.offsetLeft;
      elm = elm.offsetParent;
    }
    return parseInt(x);
  }

  this.getElementWidth = getElementWidth;
  function getElementWidth(){
    var elm;
    if(typeof(p_elm) == "object"){
      elm = p_elm;
    } else {
      elm = document.getElementById(p_elm);
    }
    return parseInt(elm.offsetWidth);
  }

  this.getElementRight = getElementRight;
  function getElementRight(){
    return getElementLeft(p_elm) + getElementWidth(p_elm);
  }

  this.getElementTop = getElementTop;
  function getElementTop() {
    var y = 0;
    var elm;
    if(typeof(p_elm) == "object"){
      elm = p_elm;
    } else {
      elm = document.getElementById(p_elm);
    }
    while (elm != null) {
      y+= elm.offsetTop;
      elm = elm.offsetParent;
    }
    return parseInt(y);
  }

  this.getElementHeight = getElementHeight;
  function getElementHeight(){
    var elm;
    if(typeof(p_elm) == "object"){
      elm = p_elm;
    } else {
      elm = document.getElementById(p_elm);
    }
    return parseInt(elm.offsetHeight);
  }

  this.getElementBottom = getElementBottom;
  function getElementBottom(){
    return getElementTop(p_elm) + getElementHeight(p_elm);
  }
}

function CalendarControl() {

  var calendarId = 'CalendarControl';
  var currentYear = 0;
  var currentMonth = 0;
  var currentDay = 0;

  var selectedYear = 0;
  var selectedMonth = 0;
  var selectedDay = 0;

  var months = ['January','February','March','April','May','June','July','August','September','October','November','December'];
  var dateField = null;

  function getProperty(p_property){
    var p_elm = calendarId;
    var elm = null;

    if(typeof(p_elm) == "object"){
      elm = p_elm;
    } else {
      elm = document.getElementById(p_elm);
    }
    if (elm != null){
      if(elm.style){
        elm = elm.style;
        if(elm[p_property]){
          return elm[p_property];
        } else {
          return null;
        }
      } else {
        return null;
      }
    }
  }

  function setElementProperty(p_property, p_value, p_elmId){
    var p_elm = p_elmId;
    var elm = null;

    if(typeof(p_elm) == "object"){
      elm = p_elm;
    } else {
      elm = document.getElementById(p_elm);
    }
    if((elm != null) && (elm.style != null)){
      elm = elm.style;
      elm[ p_property ] = p_value;
    }
  }

  function setProperty(p_property, p_value) {
    setElementProperty(p_property, p_value, calendarId);
  }

  function getDaysInMonth(year, month) {
    return [31,((!(year % 4 ) && ( (year % 100 ) || !( year % 400 ) ))?29:28),31,30,31,30,31,31,30,31,30,31][month-1];
  }

  function getDayOfWeek(year, month, day) {
    var date = new Date(year,month-1,day)
    return date.getDay();
  }

  this.setDate = setDate;
  function setDate(year, month, day) {
    if (dateField) {
      if (month < 10) {month = "0" + month;}
      if (day < 10) {day = "0" + day;}

      var dateString = day+"/"+month+"/"+year;
      dateField.value = dateString;
      hide();
    }
    return;
  }

  // Converts 1 or 2 digit years to 4 digit years.
        function to4Year(sYear)
        {
            // Pad 1 digit years with a leading zero
            if (sYear.length == 1)
                sYear = '0' + sYear;

            // Convert 2 digit years to 4 digit years
            if (sYear.length == 2) {

                var current4Year = new Date().getFullYear().toString();
                var currentCentury = parseInt(current4Year.substring(0,2));
                var current2Year = parseInt(current4Year.substring(2,4));
                var switchYear = 0;
                var startCentury = 0;
                var endCentury = 0;
                if (current2Year + 50 > 100) {
                    switchYear = Math.abs(current2Year - 50);
                    startCentury = currentCentury;
                } else {
                    switchYear = current2Year + 50;
                    startCentury = currentCentury - 1;
                }
                endCentury = startCentury + 1;

                if (sYear > switchYear)
                    sYear = startCentury + sYear;
                else
                    sYear = endCentury + sYear;
            }

            return sYear;
        }

	// Formats the text as a date using the specified
	// mask
	function AutoDateTime(e, mask)
	{
		// Fix Date() constructor issue with st, nd, rd suffixes
		// (th works for some reason)
		var regexp = /st|nd|rd/g
		var s = new String(e.value)
		s = s.replace(regexp, '')
		
		// Fix Date constructor issue with '.'
		regexp = /\./g
		s = s.replace(regexp, '/')
		
		// Re-order the day and month components if in (dd/mm/yy) format
		if (s.indexOf('/',0) > 0)
		{
			var dateParts = s.split('/')
			var d = new Date(dateParts[1] + '/' + dateParts[0] + '/' + to4Year(dateParts[2]))
		}
		else
		{
			var d = new Date(s)
		}
		if (!(isNaN(d)))
		{
			// Apply the user defined output format
			e.value = d.format(mask)
		}
	}

	Date.MONTHS = [
	'January', 'February', 'March', 'April', 'May', 'June', 'July',
	'August', 'September', 'October', 'November', 'December'
	];

	Date.DAYS = [
	'Sunday', 'Monday', 'Tuesday', 'Wednesday',
	'Thursday', 'Friday', 'Saturday'
	];

	Date.SUFFIXES = [
	'st','nd','rd','th','th','th','th','th','th','th',
	'th','th','th','th','th','th','th','th','th','th',
	'st','nd','rd','th','th','th','th','th','th','th',
	'st'
	];

	// Date prototype to format based on the supplied mask
	Date.prototype.format = function( mask ) {
		var formatted     = ( mask != null ) ? mask : 'DD-MMM-YY';
		var letters       = 'DdMYyHdhmst'.split( '' );
		var temp          = new Array();
		var count         = 0;
		var regexA;
		var regexB        = /\[(\d+)\]/;

		var day           = this.getDay();
		var date          = this.getDate();
		var month         = this.getMonth();
		var year          = this.getFullYear().toString();
		var hours         = this.getHours();
		var minutes       = this.getMinutes();
		var seconds       = this.getSeconds();

		var formats       = new Object();
		formats[ 'D' ]    = date;
		formats[ 'd' ]    = date + Date.SUFFIXES[ date - 1 ];
		formats[ 'DD' ]   = ( date < 10 ) ? '0' + date : date;
		formats[ 'dd' ]   = ( date < 10 ) ? '0' + date : date;
		formats[ 'DDD' ]  = Date.DAYS[ day ].substring( 0, 3 );
		formats[ 'DDDD' ] = Date.DAYS[ day ];
		formats[ 'M' ]    = month + 1;
		formats[ 'MM' ]   = ( month + 1 < 10 ) ? '0' + ( month + 1 ) : month + 1;
		formats[ 'MMM' ]  = Date.MONTHS[ month ].substring( 0, 3 );
		formats[ 'MMMM' ] = Date.MONTHS[ month ];
		formats[ 'Y' ]    = ( year.charAt( 2 ) == '0' ) ? year.charAt( 3 ) : year.substring( 2, 4 );
		formats[ 'YY' ]   = year.substring( 2, 4 );
		formats[ 'YYYY' ] = year;
        formats[ 'yyyy' ] = year;
		formats[ 'H' ]    = hours;
		formats[ 'HH' ]   = ( hours < 10 ) ? '0' + hours : hours;  
		formats[ 'h' ]    = ( hours > 12 || hours == 0 ) ? Math.abs( hours - 12 ) : hours;
		formats[ 'hh' ]   = ( formats[ 'h' ] < 10 ) ? '0' + formats[ 'h' ] : formats[ 'h' ];
		formats[ 'm' ]    = minutes;
		formats[ 'mm' ]   = ( minutes < 10 ) ? '0' + minutes : minutes;
		formats[ 's' ]    = seconds;
		formats[ 'ss' ]   = ( seconds < 10 ) ? '0' + seconds : seconds;
		formats[ 't' ]    = ( hours < 12 ) ?  'A' : 'P';
		formats[ 'tt' ]   = ( hours < 12 ) ?  'AM' : 'PM';

		for ( var i = 0; i < letters.length; i++ ) {
			regexA = new RegExp( '(' + letters[ i ] + '+)' );
			while ( regexA.test( formatted ) ) {
			temp[ count ] = RegExp.$1;
			formatted = formatted.replace( RegExp.$1, '[' + count + ']' );
			count++;
			}
		}

		while ( regexB.test( formatted ) ) {
			formatted = formatted.replace( regexB, formats[ temp[ RegExp.$1 ] ] );
		}

		return formatted;
	}

  this.changeMonth = changeMonth;
  function changeMonth(change) {
    currentMonth += change;
    currentDay = 0;
    if(currentMonth > 12) {
      currentMonth = 1;
      currentYear++;
    } else if(currentMonth < 1) {
      currentMonth = 12;
      currentYear--;
    }

    calendar = document.getElementById(calendarId);
    calendar.innerHTML = calendarDrawTable();
  }

  this.changeYear = changeYear;
  function changeYear(change) {
    currentYear += change;
    currentDay = 0;
    calendar = document.getElementById(calendarId);
    calendar.innerHTML = calendarDrawTable();
  }

  function getCurrentYear() {
    var year = new Date().getYear();
    if(year < 1900) year += 1900;
    return year;
  }

  function getCurrentMonth() {
    return new Date().getMonth() + 1;
  } 

  function getCurrentDay() {
    return new Date().getDate();
  }

  function calendarDrawTable() {

    var dayOfMonth = 1;
    var validDay = 0;
    var startDayOfWeek = getDayOfWeek(currentYear, currentMonth, dayOfMonth);
    var daysInMonth = getDaysInMonth(currentYear, currentMonth);
    var css_class = null; //CSS class for each day

    var table = "<table cellspacing='0' cellpadding='0' border='0' >";
    table = table + "<tr class='header'>";
    table = table + "  <td colspan='2' class='previous'><a href='javascript:changeCalendarControlMonth(-1);'>&lt;</a> <a href='javascript:changeCalendarControlYear(-1);'>&laquo;</a></td>";
    table = table + "  <td colspan='3' class='title'>" + months[currentMonth-1] + "<br>" + currentYear + "</td>";
    table = table + "  <td colspan='2' class='next'><a href='javascript:changeCalendarControlYear(1);'>&raquo;</a> <a href='javascript:changeCalendarControlMonth(1);'>&gt;</a></td>";
    table = table + "</tr>";
    table = table + "<tr><th>S</th><th>M</th><th>T</th><th>W</th><th>T</th><th>F</th><th>S</th></tr>";

    for(var week=0; week < 6; week++) {
      table = table + "<tr>";
      for(var dayOfWeek=0; dayOfWeek < 7; dayOfWeek++) {
        if(week == 0 && startDayOfWeek == dayOfWeek) {
          validDay = 1;
        } else if (validDay == 1 && dayOfMonth > daysInMonth) {
          validDay = 0;
        }

        if(validDay) {
          if (dayOfMonth == selectedDay && currentYear == selectedYear && currentMonth == selectedMonth) {
            css_class = 'current';
          } else if (dayOfWeek == 0 || dayOfWeek == 6) {
            css_class = 'weekend';
          } else {
            css_class = 'weekday';
          }

          table = table + "<td><a class='"+css_class+"' href=\"javascript:setCalendarControlDate("+currentYear+","+currentMonth+","+dayOfMonth+")\">"+dayOfMonth+"</a></td>";
          dayOfMonth++;
        } else {
          table = table + "<td class='empty'>&nbsp;</td>";
        }
      }
      table = table + "</tr>";
    }

    table = table + "<tr class='header'><th colspan='7' style='padding: 3px;'><a href='javascript:hideCalendarControl();'>Close</a></td></tr>";
    table = table + "</table>";

    return table;
  }

  this.show = show;
  function show(field) {

    // If the calendar is visible and associated with
    // this field do not do anything.
    if (dateField == field) {
      return;
    } else {
      dateField = field;
    }

    if(dateField) {
      try {
          if (dateField.value != '')
          {
  			var dateParts = dateField.value.split('/')
			myDate = new Date(dateParts[1] + '/' + dateParts[0] + '/' + to4Year(dateParts[2]))
		  } else {
		    myDate = new Date();
		  }
		  
		  if ( !isNaN(myDate) )
		  {
			 selectedMonth = myDate.getMonth()+1;
			 selectedDay = myDate.getDate();
			 selectedYear = myDate.getFullYear();
		  }
      } catch(e) {alert(e);}
    }

    if (!(selectedYear && selectedMonth && selectedDay)) {
      selectedMonth = getCurrentMonth();
      selectedDay = getCurrentDay();
      selectedYear = getCurrentYear();
    }

    currentMonth = selectedMonth;
    currentDay = selectedDay;
    currentYear = selectedYear;

    if(document.getElementById){
		
      calendar = document.getElementById(calendarId);
      calendar.innerHTML = calendarDrawTable(currentYear, currentMonth);

      setElementProperty('display', 'block', 'CalendarControlIFrame');
      setProperty('display', 'block');

      var fieldPos = new positionInfo(dateField);
      var calendarPos = new positionInfo(calendarId);

      var x = fieldPos.getElementLeft();
      var y = fieldPos.getElementBottom();

      setProperty('left', x + "px");
      setProperty('top', y + "px");
      setElementProperty('left', x + "px", 'CalendarControlIFrame');
      setElementProperty('top', y + "px", 'CalendarControlIFrame');
      setElementProperty('width', calendarPos.getElementWidth() + "px", 'CalendarControlIFrame');
      setElementProperty('height', calendarPos.getElementHeight() + "px", 'CalendarControlIFrame');
    }
  }

  this.hide = hide;
  function hide() {
    if(dateField) {
      setProperty('display', 'none');
      setElementProperty('display', 'none', 'CalendarControlIFrame');
      dateField = null;
    }
  }
}

var calendarControl = new CalendarControl();

function showCalendarControl(textField) {
  calendarControl.show(textField);
}

function hideCalendarControl() {
  calendarControl.hide();
}

function setCalendarControlDate(year, month, day) {
  calendarControl.setDate(year, month, day);
}

function changeCalendarControlYear(change) {
  calendarControl.changeYear(change);
}

function changeCalendarControlMonth(change) {
  calendarControl.changeMonth(change);
}

document.write("<iframe id='CalendarControlIFrame' src='javascript:false;' frameBorder='0' scrolling='no'></iframe>");
document.write("<div id='CalendarControl'></div>");