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 = month+"-"+day+"-"+year;
			dateField.value = dateString;
			dateField.fireEvent("onchange");
			hide();
			}
		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;
		}

	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 {
				var dateString = new String(dateField.value);
				var dateParts = dateString.split("-");
        
				selectedMonth = parseInt(dateParts[0],10);
		        selectedDay = 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();

			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>");