var calendar = null; // remember the calendar object so that we reuse it and
	// avoid creation other calendars.
			
			// code from http://www.meyerweb.com -- change the active stylesheet.
			function setActiveStyleSheet(title) {
			var i, a, main;
			for(i=0; (a = document.getElementsByTagName("link")[i]); i++) {
			if(a.getAttribute("rel").indexOf("style") != -1 && a.getAttribute("title")) {
			a.disabled = true;
			if(a.getAttribute("title") == title) a.disabled = false;
			}
			}
			return false;
			}
			
			// This function gets called when the end-user clicks on some date.
			function selected(cal, date) {
			cal.sel.value = date; // just update the date in the input field.
			//if (cal.sel.id == "sel1" || cal.sel.id == "sel3")
			// if we add this call we close the calendar on single-click.
			// just to exemplify both cases, we are using this only for the 1st
			// and the 3rd field, while 2nd and 4th will still require double-click.
			//cal.callCloseHandler();
			}
			
			// And this gets called when the end-user clicks on the _selected_ date,
			// or clicks on the "Close" button.  It just hides the calendar without
			// destroying it.
			function closeHandler(cal) {
			cal.hide();                        // hide the calendar
			
			// don't check mousedown on document anymore (used to be able to hide the
			// calendar when someone clicks outside it, see the showCalendar function).
			Calendar.removeEvent(document, "mousedown", checkCalendar);
			}
			
			// This gets called when the user presses a mouse button anywhere in the
			// document, if the calendar is shown.  If the click was outside the open
			// calendar this function closes it.
			function checkCalendar(ev) {
			var el = Calendar.is_ie ? Calendar.getElement(ev) : Calendar.getTargetElement(ev);
			for (; el != null; el = el.parentNode)
			// FIXME: allow end-user to click some link without closing the
			// calendar.  Good to see real-time stylesheet change :)
			if (el == calendar.element || el.tagName == "A") break;
			if (el == null) {
			// calls closeHandler which should hide the calendar.
			calendar.callCloseHandler();
			Calendar.stopEvent(ev);
			}
			}
			
			// This function shows the calendar under the element having the given id.
			// It takes care of catching "mousedown" signals on document and hiding the
			// calendar if the click was outside.
			function showCalendar(id, format) {
			var el = document.getElementById(id);
			if (calendar != null) {
			// we already have some calendar created
			calendar.hide();                 // so we hide it first.
			} else {
			// first-time call, create the calendar.
			var cal = new Calendar(true, null, selected, closeHandler);
			calendar = cal;                  // remember it in the global var
			cal.setRange(1900, 2070);        // min/max year allowed.
			cal.create();
			}
			calendar.setDateFormat(format);    // set the specified date format
			calendar.parseDate(el.value);      // try to parse the text in field
			calendar.sel = el;                 // inform it what input field we use
			calendar.showAtElement(el);        // show the calendar below it
			
			// catch "mousedown" on document
			Calendar.addEvent(document, "mousedown", checkCalendar);
			return false;
			}
			
			var MINUTE = 60 * 1000;
			var HOUR = 60 * MINUTE;
			var DAY = 24 * HOUR;
			var WEEK = 7 * DAY;
			
			// If this handler returns true then the "date" given as
			// parameter will be disabled.  In this example we enable
			// only days within a range of 10 days from the current
			// date.
			// You can use the functions date.getFullYear() -- returns the year
			// as 4 digit number, date.getMonth() -- returns the month as 0..11,
			// and date.getDate() -- returns the date of the month as 1..31, to
			// make heavy calculations here.  However, beware that this function
			// should be very fast, as it is called for each day in a month when
			// the calendar is (re)constructed.
			function isDisabled(date) {
			var today = new Date();
			return (Math.abs(date.getTime() - today.getTime()) / DAY) > 10;
			}
			
			function flatSelected(cal, date) {
			var el = document.getElementById("preview");
			el.innerHTML = date;
			}
			
			function showFlatCalendar() {
			var parent = document.getElementById("display");
			
			// construct a calendar giving only the "selected" handler.
			var cal = new Calendar(true, null, flatSelected);
			
			// We want some dates to be disabled; see function isDisabled above
			cal.setDisabledHandler(isDisabled);
			cal.setDateFormat("DD, M d");
			
			// this call must be the last as it might use data initialized above; if
			// we specify a parent, as opposite to the "showCalendar" function above,
			// then we create a flat calendar -- not popup.  Hidden, though, but...
			cal.create(parent);
			
			// ... we can show it here.
			cal.show();
			}
			
			setActiveStyleSheet('summer');