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) {
		
	  //only select dates in future?
	  if(this.FutureDatesOnly){
		
		var currentDate = new Date();
		var newDate = new Date(year, month, day);
		var currentYear, currentMonth, currentDay;
		
		currentYear = parseInt(currentDate.getFullYear());
		currentMonth = parseInt(currentDate.getMonth()) + 1;
		currentDay = parseInt(currentDate.getDate());
		currentDate = new Date(currentYear, currentMonth, currentDay);
		
		if(newDate<currentDate){
			alert("You cannot selected dates in the past.");
			return;
		}
	  }
		
	  if (month < 10) {month = "0" + month;}
	  if (day < 10) {day = "0" + day;}

	  var dateString = day+"/"+month+"/"+year;
	  dateField.value = dateString;
	  hide();
	}
	
	try{CalendarControl_CallBack(dateString);}catch(ex){}
	
	return;
  }

  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;
  }


  var _FutureDatesOnly = false;
  this.FutureDatesOnly = _FutureDatesOnly;

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

	if(dateField) {
	  try {
		var dateString = new String(dateField.value);
		var dateParts = dateString.split("/");
		
		selectedDay = parseInt(dateParts[0],10);
		selectedMonth = parseInt(dateParts[1],10);
		selectedYear = parseInt(dateParts[2],10);
	  } catch(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();
	  var t = fieldPos.getElementTop();
	  
	  var newx, newy, ph, InPageUpper;
	  
	  if(document.documentElement && document.documentElement.scrollTop){
		ph = document.documentElement.clientHeight;
	  }else if(document.body){ph = document.body.clientHeight}
	  if((ph/2) >= y){InPageUpper=true;}else{InPageUpper=false;}  
	  if(InPageUpper){newx = x;newy = y;}else{
	      newy = ((y - calendarPos.getElementHeight()) - 20) - 550;
	      if (newy <= 0) { newy += 550; }
		newx = x;
}


	  setProperty('left', newx + "px");
	  setProperty('top', newy + "px");
	  setElementProperty('left', newx + "px", 'CalendarControlIFrame');
	  setElementProperty('top', newy + "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, futuredatesonly) {
  calendarControl.show(textField,futuredatesonly);
}

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>");