/* jQuery UI Date Picker v3.0 - previously jQuery Calendar

   Written by Marc Grabanski (m@marcgrabanski.com) and Keith Wood (kbwood@iprimus.com.au).



   Copyright (c) 2007 Marc Grabanski (http://marcgrabanski.com/code/ui-datepicker)

   Dual licensed under the MIT (MIT-LICENSE.txt)

   and GPL (GPL-LICENSE.txt) licenses.

   Date: 09-03-2007  */



/* Date picker manager.

   Use the singleton instance of this class, $.datepicker, to interact with the date picker.

   Settings for (groups of) date pickers are maintained in an instance object

   (DatepickerInstance), allowing multiple different settings on the same page. */

   

(function($) { // hide the namespace



function Datepicker() {

	this.debug = false; // Change this to true to start debugging

	this._nextId = 0; // Next ID for a date picker instance

	this._inst = []; // List of instances indexed by ID

	this._curInst = null; // The current instance in use

	this._disabledInputs = []; // List of date picker inputs that have been disabled

	this._datepickerShowing = false; // True if the popup picker is showing , false if not

	this._inDialog = false; // True if showing within a "dialog", false if not

	this.regional = []; // Available regional settings, indexed by language code

	this.regional[''] = { // Default regional settings

		clearText: 'Clear', // Display text for clear link

		closeText: 'Close', // Display text for close link

		prevText: '&lt;Prev', // Display text for previous month link

		nextText: 'Next&gt;', // Display text for next month link

		currentText: 'Today', // Display text for current month link

		dayNames: ['Su','Mo','Tu','We','Th','Fr','Sa'], // Names of days starting at Sunday

		monthNames: ['January','February','March','April','May','June',

			'July','August','September','October','November','December'], // Names of months

		dateFormat: 'MDY/', // First three are day, month, year in the required order,

			// fourth (optional) is the separator, e.g. US would be 'MDY/', ISO would be 'YMD-'

		firstDay: 0 // The first day of the week, Sun = 0, Mon = 1, ...

	};

	this._defaults = { // Global defaults for all the date picker instances

		showOn: 'focus', // 'focus' for popup on focus,

			// 'button' for trigger button, or 'both' for either

		defaultDate: null, // Used when field is blank: actual date,

			// +/-number for offset from today, null for today

		appendText: '', // Display text following the input box, e.g. showing the format

		buttonText: '...', // Text for trigger button

		buttonImage: '', // URL for trigger button image

		buttonImageOnly: false, // True if the image appears alone, false if it appears on a button

		closeAtTop: true, // True to have the clear/close at the top,

			// false to have them at the bottom

		hideIfNoPrevNext: false, // True to hide next/previous month links

			// if not applicable, false to just disable them

		changeMonth: true, // True if month can be selected directly, false if only prev/next

		changeYear: true, // True if year can be selected directly, false if only prev/next

		yearRange: '-10:+10', // Range of years to display in drop-down,

			// either relative to current year (-nn:+nn) or absolute (nnnn:nnnn)

		changeFirstDay: true, // True to click on day name to change, false to remain as set

		showOtherMonths: false, // True to show dates in other months, false to leave blank

		useShortYear: false, // True to show years as YY, false to show them as YYYY

		shortYearCutoff: '+10', // Short year values < this are in the current century,

			// > this are in the previous century, 

			// string value starting with '+' for current year + value

		minDate: null, // The earliest selectable date, or null for no limit

		maxDate: null, // The latest selectable date, or null for no limit

		speed: 'medium', // Speed of display/closure

		beforeShowDay: null, // Function that takes a date and returns an array with

			// [0] = true if selectable, false if not,

			// [1] = custom CSS class name(s) or '', e.g. $.datepicker.noWeekends

		beforeShow: null, // Function that takes an input field and

			// returns a set of custom settings for the date picker

		onSelect: null, // Define a callback function when a date is selected

		numberOfMonths: 1, // Number of months to show at a time

		stepMonths: 1, // Number of months to step back/forward

		rangeSelect: false, // Allows for selecting a date range on one date picker

		rangeSeparator: ' - ' // Text between two dates in a range

	};

	$.extend(this._defaults, this.regional['']);

	this._datepickerDiv = $('<div id="datepicker_div"></div>');

}



$.extend(Datepicker.prototype, {

	/* Class name added to elements to indicate already configured with a date picker. */

	markerClassName: 'hasDatepicker',



	/* Debug logging (if enabled). */

	log: function () {

		if (this.debug) {

			console.log.apply('', arguments);

		}

	},

	

	/* Register a new date picker instance - with custom settings. */

	_register: function(inst) {

		var id = this._nextId++;

		this._inst[id] = inst;

		return id;

	},



	/* Retrieve a particular date picker instance based on its ID. */

	_getInst: function(id) {

		return this._inst[id] || id;

	},



	/* Override the default settings for all instances of the date picker. 

	   @param  settings  object - the new settings to use as defaults (anonymous object)

	   @return the manager object */

	setDefaults: function(settings) {

		extendRemove(this._defaults, settings || {});

		return this;

	},



	/* Handle keystrokes. */

	_doKeyDown: function(e) {

		var inst = $.datepicker._getInst(this._calId);

		if ($.datepicker._datepickerShowing) {

			switch (e.keyCode) {

				case 9:  $.datepicker.hideDatepicker('');

						break; // hide on tab out
				case 13: $.datepicker._selectDay(inst, inst._selectedMonth, inst._selectedYear,

							$('td.datepicker_daysCellOver', inst._datepickerDiv)[0]);

						break; // select the value on enter

				case 27: $.datepicker.hideDatepicker(inst._get('speed'));

						break; // hide on escape

				case 33: $.datepicker._adjustDate(inst,

							(e.ctrlKey ? -1 : -inst._get('stepMonths')), (e.ctrlKey ? 'Y' : 'M'));

						break; // previous month/year on page up/+ ctrl

				case 34: $.datepicker._adjustDate(inst,

							(e.ctrlKey ? +1 : +inst._get('stepMonths')), (e.ctrlKey ? 'Y' : 'M'));

						break; // next month/year on page down/+ ctrl

				case 35: if (e.ctrlKey) $.datepicker._clearDate(inst);

						break; // clear on ctrl+end

				case 36: if (e.ctrlKey) $.datepicker._gotoToday(inst);

						break; // current on ctrl+home

				case 37: if (e.ctrlKey) $.datepicker._adjustDate(inst, -1, 'D');

						break; // -1 day on ctrl+left

				case 38: if (e.ctrlKey) $.datepicker._adjustDate(inst, -7, 'D');

						break; // -1 week on ctrl+up

				case 39: if (e.ctrlKey) $.datepicker._adjustDate(inst, +1, 'D');

						break; // +1 day on ctrl+right

				case 40: if (e.ctrlKey) $.datepicker._adjustDate(inst, +7, 'D');

						break; // +1 week on ctrl+down

			}

		}

		else if (e.keyCode == 36 && e.ctrlKey) { // display the date picker on ctrl+home

			$.datepicker.showFor(this);

		}

	},



	/* Filter entered characters. */

	_doKeyPress: function(e) {

		var inst = $.datepicker._getInst(this._calId);

		var chr = String.fromCharCode(e.charCode == undefined ? e.keyCode : e.charCode);

		return (chr < ' ' || chr == inst._get('dateFormat').charAt(3) ||

			(chr >= '0' && chr <= '9')); // only allow numbers and separator

	},



	/* Attach the date picker to an input field. */

	_connectDatepicker: function(target, inst) {

		var input = $(target);

		if (this._hasClass(input, this.markerClassName)) {

			return;

		}

		var appendText = inst._get('appendText');

		if (appendText) {

			input.after('<span class="datepicker_append">' + appendText + '</span>');

		}

		var showOn = inst._get('showOn');

		if (showOn == 'focus' || showOn == 'both') { // pop-up date picker when in the marked field

			input.focus(this.showFor);

		}

		if (showOn == 'button' || showOn == 'both') { // pop-up date picker when button clicked

			var buttonText = inst._get('buttonText');

			var buttonImage = inst._get('buttonImage');

			var buttonImageOnly = inst._get('buttonImageOnly');

			var trigger = $(buttonImageOnly ? '<img class="datepicker_trigger" src="' +

				buttonImage + '" alt="' + buttonText + '" title="' + buttonText + '"/>' :

				'<button type="button" class="datepicker_trigger">' + (buttonImage != '' ?

				'<img src="' + buttonImage + '" alt="' + buttonText + '" title="' + buttonText + '"/>' :

				buttonText) + '</button>');

			input.wrap('<span class="datepicker_wrap"></span>').after(trigger);

			trigger.click(this.showFor);

		}

		input.addClass(this.markerClassName).keydown(this._doKeyDown).keypress(this._doKeyPress);

		input[0]._calId = inst._id;

	},



	/* Attach an inline date picker to a div. */

	_inlineDatepicker: function(target, inst) {

		var input = $(target);

		if (this._hasClass(input, this.markerClassName)) {

			return;

		}

		input.addClass(this.markerClassName).append(inst._datepickerDiv);

		input[0]._calId = inst._id;

		this._updateDatepicker(inst);

		inst._datepickerDiv.resize(function() { $.datepicker._inlineShow(inst); });

	},



	/* Tidy up after displaying the date picker. */

	_inlineShow: function(inst) {

		var numMonths = inst._get('numberOfMonths'); // fix width for dynamic number of date pickers

		numMonths = (numMonths == null ? 1 : (typeof numMonths == 'number' ? numMonths : numMonths[1]));

		inst._datepickerDiv.width(numMonths * $('.datepicker', inst._datepickerDiv[0]).width());

	},



	/* Does this element have a particular class? */

	_hasClass: function(element, className) {

		var classes = element.attr('class');

		return (classes && classes.indexOf(className) > -1);

	},



	/* Pop-up the date picker in a "dialog" box.

	   @param  dateText  string - the initial date to display (in the current format)

	   @param  onSelect  function - the function(dateText) to call when a date is selected

	   @param  settings  object - update the dialog date picker instance's settings (anonymous object)

	   @param  pos       int[2] - coordinates for the dialog's position within the screen

	                     leave empty for default (screen centre)

	   @return the manager object */

	dialogDatepicker: function(dateText, onSelect, settings, pos) {

		var inst = this._dialogInst; // internal instance

		if (!inst) {

			inst = this._dialogInst = new DatepickerInstance({}, false);

			this._dialogInput = $('<input type="text" size="1" style="position: absolute; top: -100px;"/>');

			this._dialogInput.keydown(this._doKeyDown);

			$('body').append(this._dialogInput);

			this._dialogInput[0]._calId = inst._id;

		}

		extendRemove(inst._settings, settings || {});

		this._dialogInput.val(dateText);



		var viewportWidth;

		var viewportHeight;

		if (window.innerWidth) { // Mozilla/Netscape/Opera/IE7

			viewportWidth = window.innerWidth,

			viewportHeight = window.innerHeight

		}

		else if (document.documentElement && document.documentElement.clientWidth &&

				document.documentElement.clientWidth != 0) { // IE6 standards compliant

			viewportWidth = document.documentElement.clientWidth,

			viewportHeight = document.documentElement.clientHeight

		}

		else { // older IE

			viewportWidth = document.getElementsByTagName('body')[0].clientWidth,

			viewportHeight = document.getElementsByTagName('body')[0].clientHeight

		}

		

		this._pos = pos || // should use actual width/height below

			[(viewportWidth / 2) - 100, (viewportHeight / 2) - 150];

		this._pos[1] = this._pos[1] + // add the browser scroll position to the height

			(document.documentElement && document.documentElement.scrollTop ?

			document.documentElement.scrollTop : document.body.scrollTop);



		// move input on screen for focus, but hidden behind dialog

		this._dialogInput.css('left', this._pos[0] + 'px').css('top', this._pos[1] + 'px');

		inst._settings.onSelect = onSelect;

		this._inDialog = true;

		this._datepickerDiv.addClass('datepicker_dialog');

		this.showFor(this._dialogInput[0]);

		if ($.blockUI) {

			$.blockUI(this._datepickerDiv);

		}

		return this;

	},



	/* Enable the input field(s) for entry.

	   @param  inputs  element - single input field or

	                   string - the ID or other jQuery selector of the input field(s) or

	                   object - jQuery collection of input fields

	   @return the manager object */

	enableFor: function(inputs) {

		inputs = (inputs.jquery ? inputs : $(inputs));

		inputs.each(function() {

			this.disabled = false;

			$(this).siblings('button.datepicker_trigger').each(function() { this.disabled = false; });

			$(this).siblings('img.datepicker_trigger').css({opacity: '1.0', cursor: ''});

			var $this = this;

			$.datepicker._disabledInputs = $.map($.datepicker._disabledInputs,

				function(value) { return (value == $this ? null : value); }); // delete entry

		});

		return this;

	},



	/* Disable the input field(s) from entry.

	   @param  inputs  element - single input field or

	                   string - the ID or other jQuery selector of the input field(s) or

	                   object - jQuery collection of input fields

	   @return the manager object */

	disableFor: function(inputs) {

		inputs = (inputs.jquery ? inputs : $(inputs));

		inputs.each(function() {

			this.disabled = true;

			$(this).siblings('button.datepicker_trigger').each(function() { this.disabled = true; });

			$(this).siblings('img.datepicker_trigger').css({opacity: '0.5', cursor: 'default'});

			var $this = this;

			$.datepicker._disabledInputs = $.map($.datepicker._disabledInputs,

				function(value) { return (value == $this ? null : value); }); // delete entry

			$.datepicker._disabledInputs[$.datepicker._disabledInputs.length] = this;

		});

		return this;

	},



	/* Is the input field disabled?

	   @param  input  element - single input field or

	                  string - the ID or other jQuery selector of the input field or

	                  object - jQuery collection of input field

	   @return boolean - true if disabled, false if enabled */

	isDisabled: function(input) {

		input = (input.jquery ? input[0] : (typeof input == 'string' ? $(input)[0] : input));

		for (var i = 0; i < $.datepicker._disabledInputs.length; i++) {

			if ($.datepicker._disabledInputs[i] == input) {

				return true;

			}

		}

		return false;

	},



	/* Update the settings for a date picker attached to an input field or division.

	   @param  control   element - the input field or div/span attached to the date picker or

	                     string - the ID or other jQuery selector of the input field or

	                     object - jQuery object for input field or div/span

	   @param  settings  object - the new settings to update

	   @return the manager object */

	reconfigureFor: function(control, settings) {

		control = (control.jquery ? control[0] :

			(typeof control == 'string' ? $(control)[0] : control));

		var inst = this._getInst(control._calId);

		if (inst) {

			extendRemove(inst._settings, settings || {});

			this._updateDatepicker(inst);

		}

		return this;

	},



	/* Set the date for a date picker attached to an input field or division.

	   @param  control  element - the input field or div/span attached to the date picker or

	                    string - the ID or other jQuery selector of the input field or

	                    object - jQuery object for input field or div/span

	   @param  date     Date - the new date

	   @param  endDate  Date - the new end date for a range (optional)

	   @return the manager object */

	setDateFor: function(control, date, endDate) {

		control = (control.jquery ? control[0] :

			(typeof control == 'string' ? $(control)[0] : control));

		var inst = this._getInst(control._calId);

		if (inst) {

			inst._setDate(date, endDate);

			this._updateDatepicker(inst);

		}

		return this;

	},



	/* Retrieve the date for a date picker attached to an input field or division.

	   @param  control  element - the input field or div/span attached to the date picker or

	                    string - the ID or other jQuery selector of the input field or

	                    object - jQuery object for input field or div/span

	   @return Date - the current date or

	           Date[2] - the current dates for a range*/

	getDateFor: function(control) {

		control = (control.jquery ? control[0] :

			(typeof control == 'string' ? $(control)[0] : control));

		var inst = this._getInst(control._calId);

		return (inst ? inst._getDate() : null);

	},



	/* Pop-up the date picker for a given input field.

	   @param  control  element - the input field attached to the date picker or

	                    string - the ID or other jQuery selector of the input field or

	                    object - jQuery object for input field

	   @return the manager object */

	showFor: function(control) {

		control = (control.jquery ? control[0] :

			(typeof control == 'string' ? $(control)[0] : control));

		var input = (control.nodeName && control.nodeName.toLowerCase() == 'input' ? control : this);

		if (input.nodeName.toLowerCase() != 'input') { // find from button/image trigger

			input = $('input', input.parentNode)[0];

		}

		if ($.datepicker._lastInput == input) { // already here

			return;

		}

		if ($.datepicker.isDisabled(input)) {

			return;

		}

		var inst = $.datepicker._getInst(input._calId);

		var beforeShow = inst._get('beforeShow');

		extendRemove(inst._settings, (beforeShow ? beforeShow(input) : {}));

		$.datepicker.hideDatepicker('');

		$.datepicker._lastInput = input;

		inst._setDateFromField(input);

		if ($.datepicker._inDialog) { // hide cursor

			input.value = '';

		}

		if (!$.datepicker._pos) { // position below input

			$.datepicker._pos = $.datepicker._findPos(input);

			$.datepicker._pos[1] += input.offsetHeight; // add the height

		}

		inst._datepickerDiv.css('position', ($.datepicker._inDialog && $.blockUI ? 'static' : 'absolute')).

			css('left', $.datepicker._pos[0] + 'px').css('top', $.datepicker._pos[1] + 'px');

		$.datepicker._pos = null;

		$.datepicker._showDatepicker(inst);

		return this;

	},



	/* Construct and display the date picker. */

	_showDatepicker: function(id) {

		var inst = this._getInst(id);

		inst._rangeStart = null;

		this._updateDatepicker(inst);

		if (!inst._inline) {

			var speed = inst._get('speed');

			var postProcess = function() {

				$.datepicker._datepickerShowing = true;

				$.datepicker._afterShow(inst);

			};

			inst._datepickerDiv.show(speed, postProcess);

			if (speed == '') {

				postProcess();

			}

			if (inst._input[0].type != 'hidden') {

				inst._input[0].focus();

			}

			this._curInst = inst;

		}

	},



	/* Generate the date picker content. */

	_updateDatepicker: function(inst) {

		inst._datepickerDiv.empty().append(inst._generateDatepicker());

		if (inst._get('numberOfMonths') != 1) {

			inst._datepickerDiv.addClass('datepicker_multi');

		} 

		else {

			inst._datepickerDiv.removeClass('datepicker_multi');

		}

		if (inst._input && inst._input[0].type != 'hidden') {

			inst._input[0].focus();

		}

	},



	/* Tidy up after displaying the date picker. */

	_afterShow: function(inst) {

		var numMonths = inst._get('numberOfMonths'); // fix width for dynamic number of date pickers

		numMonths = (numMonths == null ? 1 : (typeof numMonths == 'number' ? numMonths : numMonths[1]));

		inst._datepickerDiv.width(numMonths * $('.datepicker', inst._datepickerDiv[0]).width());

		if ($.browser.msie) { // fix IE < 7 select problems

			$('#datepicker_cover').css({width: inst._datepickerDiv.width() + 4,

				height: inst._datepickerDiv.height() + 4});

		}

		// re-position on screen if necessary

		var pos = $.datepicker._findPos(inst._input[0]);

		browserWidth = $(window).width();

		if (document.documentElement && (document.documentElement.scrollLeft)) {

			browserX = document.documentElement.scrollLeft;	

		}

		else {

			browserX = document.body.scrollLeft;

		}

		// reposition date picker if outside the browser window

		if ((inst._datepickerDiv.offset().left + inst._datepickerDiv.width()) > (browserWidth + browserX)) {

			inst._datepickerDiv.css('left', (pos[0] + $(inst._input[0]).width() - inst._datepickerDiv.width()) + 'px');

		}

		browserHeight = $(window).height();

		if (document.documentElement && (document.documentElement.scrollTop)) {

			browserTopY = document.documentElement.scrollTop;

		} 

		else {

			browserTopY = document.body.scrollTop;

		}

		// reposition date picker if outside the browser window

		if ((inst._datepickerDiv.offset().top + inst._datepickerDiv.height()) > (browserTopY + browserHeight) ) {

			inst._datepickerDiv.css('top', (pos[1] - inst._datepickerDiv.height()) + 'px');

		}

	},



	/* Hide the date picker from view.

	   @param  speed  string - the speed at which to close the date picker

	   @return void */

	hideDatepicker: function(speed) {

		var inst = this._curInst;
		if (!inst) {
			return;

		}
		var rangeSelect = inst._get('rangeSelect');

		if (rangeSelect && this._stayOpen) {

			this._selectDate(inst, inst._formatDate(

				inst._currentDay, inst._currentMonth, inst._currentYear));

		}

		this._stayOpen = false;

		if (this._datepickerShowing) {

			speed = (speed != null ? speed : inst._get('speed'));

			inst._datepickerDiv.hide(speed, function() {

				$.datepicker._tidyDialog(inst);

			});

			if (speed == '') {

				this._tidyDialog(inst);

			}

			this._datepickerShowing = false;

			this._lastInput = null;

			inst._settings.prompt = null;

			if (this._inDialog) {

				this._dialogInput.css('position', 'absolute').

					css('left', '0px').css('top', '-100px');

				if ($.blockUI) {

					$.unblockUI();

					$('body').append(this._datepickerDiv);

				}

			}

			this._inDialog = false;

		}

		this._curInst = null;

	},



	/* Tidy up after a dialog display. */

	_tidyDialog: function(inst) {

		inst._datepickerDiv.removeClass('datepicker_dialog');

		$('.datepicker_prompt', inst._datepickerDiv).remove();

	},



	/* Close date picker if clicked elsewhere. */

	_checkExternalClick: function(event) {

		if (!$.datepicker._curInst) {

			return;

		}

		var target = $(event.target);

		if ((target.parents("#datepicker_div").length == 0) &&

				(target.attr('class') != 'datepicker_trigger') &&

				$.datepicker._datepickerShowing && !($.datepicker._inDialog && $.blockUI)) {

			$.datepicker.hideDatepicker('');

		}

	},



	/* Adjust one of the date sub-fields. */

	_adjustDate: function(id, offset, period) {

		var inst = this._getInst(id);

		inst._adjustDate(offset, period);

		this._updateDatepicker(inst);

	},



	/* Action for current link. */

	_gotoToday: function(id) {

		var date = new Date();

		var inst = this._getInst(id);

		inst._selectedDay = date.getDate();

		inst._selectedMonth = date.getMonth();

		inst._selectedYear = date.getFullYear();

		this._adjustDate(inst);

	},



	/* Action for selecting a new month/year. */

	_selectMonthYear: function(id, select, period) {

		var inst = this._getInst(id);

		inst._selectingMonthYear = false;

		inst[period == 'M' ? '_selectedMonth' : '_selectedYear'] =

			select.options[select.selectedIndex].value - 0;

		this._adjustDate(inst);

	},



	/* Restore input focus after not changing month/year. */

	_clickMonthYear: function(id) {

		var inst = this._getInst(id);

		if (inst._input && inst._selectingMonthYear && !$.browser.msie) {

			inst._input[0].focus();

		}

		inst._selectingMonthYear = !inst._selectingMonthYear;

	},



	/* Action for changing the first week day. */

	_changeFirstDay: function(id, a) {

		var inst = this._getInst(id);

		var dayNames = inst._get('dayNames');

		var value = a.firstChild.nodeValue;

		for (var i = 0; i < 7; i++) {

			if (dayNames[i] == value) {

				inst._settings.firstDay = i;

				break;

			}

		}

		this._updateDatepicker(inst);

	},



	/* Action for selecting a day. */

	_selectDay: function(id, month, year, td) {
		if (this._hasClass($(td), 'datepicker_unselectable')) {

			return;

		}
		
		var inst = this._getInst(id);
		var rangeSelect = inst._get('rangeSelect');

		if (rangeSelect) {

			if (!this._stayOpen) {

				$('.datepicker td').removeClass('datepicker_currentDay');

				$(td).addClass('datepicker_currentDay');

			} 

			this._stayOpen = !this._stayOpen;

		}

		inst._currentDay = $('a', td).html();

		inst._currentMonth = month;

		inst._currentYear = year;

		this._selectDate(id, inst._formatDate(

			inst._currentDay, inst._currentMonth, inst._currentYear));

		if (this._stayOpen) {

			inst._endDay = inst._endMonth = inst._endYear = null;

			inst._rangeStart = new Date(inst._currentYear, inst._currentMonth, inst._currentDay);

			this._updateDatepicker(inst);

		}

		else if (rangeSelect) {

			if (inst._inline) {

				inst._endDay = inst._currentDay;

				inst._endMonth = inst._currentMonth;

				inst._endYear = inst._currentYear;

				inst._selectedDay = inst._currentDay = inst._rangeStart.getDate();

				inst._selectedMonth = inst._currentMonth = inst._rangeStart.getMonth();

				inst._selectedYear = inst._currentYear = inst._rangeStart.getFullYear();

				inst._rangeStart = null;

				this._updateDatepicker(inst);

			}

			else {

				inst._rangeStart = null;

			}

		}
		

	},



	/* Erase the input field and hide the date picker. */

	_clearDate: function(id) {

		var inst = this._getInst(id);

		this._stayOpen = false;

		inst._rangeStart = null;

		this._selectDate(inst, '');

	},



	/* Update the input field with the selected date. */

	_selectDate: function(id, dateStr) {

		var inst = this._getInst(id);

		dateStr = (dateStr != null ? dateStr : inst._formatDate());

		if (inst._rangeStart) {

			dateStr = inst._formatDate(inst._rangeStart) + inst._get('rangeSeparator') + dateStr;

		}

		if (inst._input) {

			inst._input.val(dateStr);

		}

		var onSelect = inst._get('onSelect');

		if (onSelect) {

			onSelect(dateStr, inst);  // trigger custom callback

		}

		else {

			inst._input.trigger('change'); // fire the change event

		}

		if (inst._inline) {

			this._updateDatepicker(inst);

		}

		else {

			if (!this._stayOpen) {

				this.hideDatepicker(inst._get('speed'));

			}

		}

	},



	/* Set as beforeShowDay function to prevent selection of weekends.

	   @param  date  Date - the date to customise

	   @return [boolean, string] - is this date selectable?, what is its CSS class? */

	noWeekends: function(date) {

		var day = date.getDay();

		return [(day > 0 && day < 6), ''];

	},

	

	/* Find an object's position on the screen. */

	_findPos: function(obj) {

		while (obj && (obj.type == 'hidden' || obj.nodeType != 1)) {

			obj = obj.nextSibling;

		}

		var curleft = curtop = 0;

		if (obj && obj.offsetParent) {

			curleft = obj.offsetLeft;

			curtop = obj.offsetTop;

			while (obj = obj.offsetParent) {

				var origcurleft = curleft;

				curleft += obj.offsetLeft;

				if (curleft < 0) {

					curleft = origcurleft;

				}

				curtop += obj.offsetTop;

			}

		}

		return [curleft,curtop];

	}

});



/* Individualised settings for date picker functionality applied to one or more related inputs.

   Instances are managed and manipulated through the Datepicker manager. */

function DatepickerInstance(settings, inline) {

	this._id = $.datepicker._register(this);

	this._selectedDay = 0;

	this._selectedMonth = 0; // 0-11

	this._selectedYear = 0; // 4-digit year

	this._input = null; // The attached input field

	this._inline = inline; // True if showing inline, false if used in a popup

	this._datepickerDiv = (!inline ? $.datepicker._datepickerDiv :

		$('<div id="datepicker_div_' + this._id + '" class="datepicker_inline"></div>'));

	// customise the date picker object - uses manager defaults if not overridden

	this._settings = extendRemove({}, settings || {}); // clone

	if (inline) {

		this._setDate(this._getDefaultDate());

	}

}



$.extend(DatepickerInstance.prototype, {

	/* Get a setting value, defaulting if necessary. */

	_get: function(name) {

		return (this._settings[name] != null ? this._settings[name] : $.datepicker._defaults[name]);

	},



	/* Parse existing date and initialise date picker. */

	_setDateFromField: function(input) {

		this._input = $(input);

		var dateFormat = this._get('dateFormat');

		var currentDate = this._input.val().split(dateFormat.charAt(3));

		this._endDay = this._endMonth = this._endYear = null;

		var shortYearCutoff = this._get('shortYearCutoff');

		shortYearCutoff = (typeof shortYearCutoff != 'string' ? shortYearCutoff :

			new Date().getFullYear() % 100 + parseInt(shortYearCutoff, 10));

		var checkYear = function(year) {

			if (year >= 100) {

				return year;

			}

			var fullYear = new Date().getFullYear();

			return fullYear - (fullYear % 100) + year + (year <= shortYearCutoff ? 0 : -100);

		};

		if (currentDate.length == 3) {

			this._currentDay = parseInt(currentDate[dateFormat.indexOf('D')], 10);

			this._currentMonth = parseInt(currentDate[dateFormat.indexOf('M')], 10) - 1;

			this._currentYear = checkYear(parseInt(currentDate[dateFormat.indexOf('Y')], 10));

		} 

		else if (currentDate.length == 5) { // if it's a date range

			currentDateArray = this._input.val().split(this._get('rangeSeparator'));

			currentDate = currentDateArray[0].split(dateFormat.charAt(3));

			this._currentDay = parseInt(currentDate[dateFormat.indexOf('D')], 10);

			this._currentMonth = parseInt(currentDate[dateFormat.indexOf('M')], 10) - 1;

			this._currentYear = checkYear(parseInt(currentDate[dateFormat.indexOf('Y')], 10));

			currentDate = currentDateArray[1].split(dateFormat.charAt(3));

			this._endDay = parseInt(currentDate[dateFormat.indexOf('D')], 10);

			this._endMonth = parseInt(currentDate[dateFormat.indexOf('M')], 10) - 1;

			this._endYear = checkYear(parseInt(currentDate[dateFormat.indexOf('Y')], 10));

		}

		else {

			var date = this._getDefaultDate();

			this._currentDay = date.getDate();

			this._currentMonth = date.getMonth();

			this._currentYear = date.getFullYear();

		}

		this._selectedDay = this._currentDay;

		this._selectedMonth = this._currentMonth;

		this._selectedYear = this._currentYear;

		this._adjustDate();

	},

	

	/* Retrieve the default date shown on opening. */

	_getDefaultDate: function() {

		var offsetDate = function(offset) {

			var date = new Date();

			date.setDate(date.getDate() + offset);

			return date;

		};

		var defaultDate = this._get('defaultDate');

		return (defaultDate == null ? new Date() :

			(typeof defaultDate == 'number' ? offsetDate(defaultDate) : defaultDate));

	},



	/* Set the date(s) directly. */

	_setDate: function(date, endDate) {

		this._selectedDay = this._currentDay = date.getDate();

		this._selectedMonth = this._currentMonth = date.getMonth();

		this._selectedYear = this._currentYear = date.getFullYear();

		if (this._get('rangeSelect')) {

			if (endDate) {

				this._endDay = endDate.getDate();

				this._endMonth = endDate.getMonth();

				this._endYear = endDate.getFullYear();

			}

			else {

				this._endDay = this._currentDay;

				this._endMonth = this._currentMonth;

				this._endYear = this._currentYear;

			}

		}

		this._adjustDate();

	},



	/* Retrieve the date(s) directly. */

	_getDate: function() {

		var startDate = new Date(this._currentYear, this._currentMonth, this._currentDay);

		if (this._get('rangeSelect')) {

			return [startDate, new Date(this._endYear, this._endMonth, this._endDay)];

		}

		else {

			return startDate;

		}

	},



	/* Generate the HTML for the current state of the date picker. */

	_generateDatepicker: function() {

		var today = new Date();

		today = new Date(today.getFullYear(), today.getMonth(), today.getDate() + 2); // clear time

		// build the date picker HTML

		var controls = '<div class="datepicker_control">' +

			'<div class="datepicker_clear"><a onclick="jQuery.datepicker._clearDate(' + this._id + ');">' +

			this._get('clearText') + '</a></div>' +

			'<div class="datepicker_close"><a onclick="jQuery.datepicker.hideDatepicker();">' +

			this._get('closeText') + '</a></div></div>';

		var prompt = this._get('prompt');

		var closeAtTop = this._get('closeAtTop');

		var hideIfNoPrevNext = this._get('hideIfNoPrevNext');

		var numMonths = this._get('numberOfMonths');

		var stepMonths = this._get('stepMonths');

		var isMultiMonth = (numMonths != 1);

		numMonths = (numMonths == null ? [1, 1] : (typeof numMonths == 'number' ? [1, numMonths] : numMonths));

		// controls and links

		var html = (prompt ? '<div class="datepicker_prompt">' + prompt + '</div>' : '') +

			(closeAtTop && !this._inline ? controls : '') +

			'<div class="datepicker_links"><div class="datepicker_prev">' +

			(this._canAdjustMonth(-1) ? '<a onclick="jQuery.datepicker._adjustDate(' + this._id +

			', -' + stepMonths + ', \'M\');">' + this._get('prevText') + '</a>' :

			(hideIfNoPrevNext ? '' : '<label>' + this._get('prevText') + '</label>')) + '</div>' +

			(this._isInRange(today) ? '<div class="datepicker_current"><a ' +

			'onclick="jQuery.datepicker._gotoToday(' + this._id + ');">' + this._get('currentText') + '</a></div>' : '') +

			'<div class="datepicker_next">' +

			(this._canAdjustMonth(+1) ? '<a onclick="jQuery.datepicker._adjustDate(' + this._id +

			', +' + stepMonths + ', \'M\');">' + this._get('nextText') + '</a>' :

			(hideIfNoPrevNext ? '' : '<label>' + this._get('nextText') + '</label>')) + '</div></div>';

		var minDate = this._getMinDate();

		var maxDate = this._get('maxDate');

		var drawMonth = this._selectedMonth;

		var drawYear = this._selectedYear;

		for (var row = 0; row < numMonths[0]; row++) {

		for (var col = 0; col < numMonths[1]; col++) {

			var selectedDate = new Date(drawYear, drawMonth, this._selectedDay);

			html += '<div class="datepicker_oneMonth' + (col == 0 ? ' datepicker_newRow' : '') + '">' +

				this._generateMonthYearHeader(drawMonth, drawYear, minDate, maxDate,

				selectedDate, row > 0 || col > 0) + // draw month headers

				'<table class="datepicker" cellpadding="0" cellspacing="0"><thead>' + 

				'<tr class="datepicker_titleRow">';

			var firstDay = this._get('firstDay');

			var changeFirstDay = this._get('changeFirstDay');

			var dayNames = this._get('dayNames');

			for (var dow = 0; dow < 7; dow++) { // days of the week

				html += '<td>' + (!changeFirstDay ? '' :

					'<a onclick="jQuery.datepicker._changeFirstDay(' + this._id + ', this);">') +

					dayNames[(dow + firstDay) % 7] + (changeFirstDay ? '</a>' : '') + '</td>';

			}

			html += '</tr></thead><tbody>';

			var daysInMonth = this._getDaysInMonth(drawYear, drawMonth);

			this._selectedDay = Math.min(this._selectedDay, daysInMonth);

			var leadDays = (this._getFirstDayOfMonth(drawYear, drawMonth) - firstDay + 7) % 7;

			var currentDate = new Date(this._currentYear, this._currentMonth, this._currentDay);

			var endDate = this._endDay ? new Date(this._endYear, this._endMonth, this._endDay) : currentDate;

			var printDate = new Date(drawYear, drawMonth, 1 - leadDays);

			var numRows = (isMultiMonth ? 6 : Math.ceil((leadDays + daysInMonth) / 7)); // calculate the number of rows to generate

			var beforeShowDay = this._get('beforeShowDay');

			var showOtherMonths = this._get('showOtherMonths');

			var count = 0;

			for (var dRow = 0; dRow < numRows; dRow++) { // create date picker rows

				html += '<tr class="datepicker_daysRow">';

				for (var dow = 0; dow < 7; dow++) { // create date picker days

					var daySettings = (beforeShowDay ? beforeShowDay(printDate) : [true, '']);

					var otherMonth = (printDate.getMonth() != drawMonth);

					var unselectable = otherMonth || !daySettings[0] ||

						(minDate && printDate < minDate) || (maxDate && printDate > maxDate);

					html += '<td class="datepicker_daysCell' +

						((dow + firstDay + 6) % 7 >= 5 ? ' datepicker_weekEndCell' : '') + // highlight weekends

						(otherMonth ? ' datepicker_otherMonth' : '') + // highlight days from other months

						(printDate.getTime() == selectedDate.getTime() && drawMonth == this._selectedMonth ? ' datepicker_daysCellOver' : '') + // highlight selected day

						(unselectable ? ' datepicker_unselectable' : '') +  // highlight unselectable days

						(otherMonth && !showOtherMonths ? '' : ' ' + daySettings[1] + // highlight custom dates

						(printDate.getTime() >= currentDate.getTime() && printDate.getTime() <= endDate.getTime() ?  // in current range

						' datepicker_currentDay' : // highlight selected day

						(printDate.getTime() == today.getTime() ? ' datepicker_today' : ''))) + '"' + // highlight today (if different)

						(unselectable ? '' : ' onmouseover="$(this).addClass(\'datepicker_daysCellOver\');"' +

						' onmouseout="$(this).removeClass(\'datepicker_daysCellOver\');"' +

						' onclick="jQuery.datepicker._selectDay(' + this._id +',' + drawMonth + ',' + drawYear + ', this);"') + '>' + // actions

						(otherMonth ? (showOtherMonths ? printDate.getDate() : '&nbsp;') : // display for other months

						(unselectable ? printDate.getDate() : '<a>' + printDate.getDate() + '</a>')) + '</td>'; // display for this month

					printDate.setDate(printDate.getDate() + 1);

				}

				html += '</tr>';

			}

			drawMonth++;

			if (drawMonth > 11) {

				drawMonth = 0;

				drawYear++;

			}

			html += '</tbody></table></div>';

		}

		}

		html += (!closeAtTop && !this._inline ? controls : '') +

			'<div style="clear: both;"></div>' + (!$.browser.msie ? '' :

			'<!--[if lte IE 6.5]><iframe src="javascript:false;" class="datepicker_cover"></iframe><![endif]-->');

		return html;

	},

	

	/* Generate the month and year header. */

	_generateMonthYearHeader: function(drawMonth, drawYear, minDate, maxDate, selectedDate, secondary) {

		minDate = (this._rangeStart && minDate && selectedDate < minDate ? selectedDate : minDate);

		var html = '<div class="datepicker_header">';

		// month selection

		var monthNames = this._get('monthNames');

		if (secondary || !this._get('changeMonth')) {

			html += monthNames[drawMonth] + '&nbsp;';

		}

		else {

			var inMinYear = (minDate && minDate.getFullYear() == drawYear);

			var inMaxYear = (maxDate && maxDate.getFullYear() == drawYear);

			html += '<select class="datepicker_newMonth" ' +

				'onchange="jQuery.datepicker._selectMonthYear(' + this._id + ', this, \'M\');" ' +

				'onclick="jQuery.datepicker._clickMonthYear(' + this._id + ');">';

			for (var month = 0; month < 12; month++) {

				if ((!inMinYear || month >= minDate.getMonth()) &&

						(!inMaxYear || month <= maxDate.getMonth())) {

					html += '<option value="' + month + '"' +

						(month == drawMonth ? ' selected="selected"' : '') +

						'>' + monthNames[month] + '</option>';

				}

			}

			html += '</select>';

		}


		// year selection

		if (secondary || !this._get('changeYear')) {

			html += drawYear;

		}

		else {

			// determine range of years to display

			var years = this._get('yearRange').split(':');

			var year = 0;

			var endYear = 0;

			if (years.length != 2) {

				year = drawYear - 10;

				endYear = drawYear + 10;

			}

			else if (years[0].charAt(0) == '+' || years[0].charAt(0) == '-') {

				year = drawYear + parseInt(years[0], 10);

				endYear = drawYear + parseInt(years[1], 10);

			}

			else {

				year = parseInt(years[0], 10);

				endYear = parseInt(years[1], 10);

			}

			year = (minDate ? Math.max(year, minDate.getFullYear()) : year);

			endYear = (maxDate ? Math.min(endYear, maxDate.getFullYear()) : endYear);

			html += '<select class="datepicker_newYear" ' +

				'onchange="jQuery.datepicker._selectMonthYear(' + this._id + ', this, \'Y\');" ' +

				'onclick="jQuery.datepicker._clickMonthYear(' + this._id + ');">';

			for (; year <= endYear; year++) {

				html += '<option value="' + year + '"' +

					(year == drawYear ? ' selected="selected"' : '') +

					'>' + year + '</option>';

			}

			html += '</select>';

		}

		html += '</div>'; // Close datepicker_header

		return html;

	},



	/* Adjust one of the date sub-fields. */

	_adjustDate: function(offset, period) {

		var year = this._selectedYear + (period == 'Y' ? offset : 0);

		var month = this._selectedMonth + (period == 'M' ? offset : 0);

		var day = Math.min(this._selectedDay, this._getDaysInMonth(year, month)) +

			(period == 'D' ? offset : 0);

		var date = new Date(year, month, day);

		// ensure it is within the bounds set

		var minDate = this._getMinDate();

		var maxDate = this._get('maxDate');

		date = (minDate && date < minDate ? minDate : date);

		date = (maxDate && date > maxDate ? maxDate : date);

		this._selectedDay = date.getDate();

		this._selectedMonth = date.getMonth();

		this._selectedYear = date.getFullYear();

	},



	/* Determine the current minimum date - may be overridden for a range. */

	_getMinDate: function() {

		return this._get('minDate') || this._rangeStart;

	},



	/* Find the number of days in a given month. */

	_getDaysInMonth: function(year, month) {

		return 32 - new Date(year, month, 32).getDate();

	},



	/* Find the day of the week of the first of a month. */

	_getFirstDayOfMonth: function(year, month) {

		return new Date(year, month, 1).getDay();

	},



	/* Determines if we should allow a "next/prev" month display change. */

	_canAdjustMonth: function(offset) {

		var date = new Date(this._selectedYear, this._selectedMonth + offset, 1);

		if (offset < 0) {

			date.setDate(this._getDaysInMonth(date.getFullYear(), date.getMonth()));

		}

		return this._isInRange(date);

	},



	/* Is the given date in the accepted range? */

	_isInRange: function(date) {

		// during range selection, use minimum of selected date and range start

		var newMinDate = (!this._rangeStart ? null :

			new Date(this._selectedYear, this._selectedMonth, this._selectedDay));

		newMinDate = (newMinDate && this._rangeStart < newMinDate ? this._rangeStart : newMinDate);

		var minDate = newMinDate || this._get('minDate');

		var maxDate = this._get('maxDate');

		return ((!minDate || date >= minDate) && (!maxDate || date <= maxDate));

	},



	/* Format the given date for display. */

	_formatDate: function(day, month, year) {

		if (!day) {

			day = this._currentDay = this._selectedDay;

			month = this._currentMonth = this._selectedMonth;

			year = this._currentYear = this._selectedYear;

		}

		else if (typeof day == 'object') {

			year = day.getFullYear();

			month = day.getMonth();

			day = day.getDate();

		}

		month++; // adjust javascript month

		year = (this._get('useShortYear') ? year % 100 : year);

		var dateFormat = this._get('dateFormat');

		var dateString = '';

		for (var i = 0; i < 3; i++) {

			dateString += dateFormat.charAt(3) +

				(dateFormat.charAt(i) == 'D' ? (day < 10 ? '0' : '') + day :

				(dateFormat.charAt(i) == 'M' ? (month < 10 ? '0' : '') + month :

				(dateFormat.charAt(i) == 'Y' ? (year < 10 ? '0' : '') + year : '?')));

		}

		return dateString.substring(dateFormat.charAt(3) ? 1 : 0);

	}

});



/* jQuery extend now ignores nulls! */

function extendRemove(target, props) {

	$.extend(target, props);

	for (var name in props) {

		if (props[name] == null) {

			target[name] = null;

		}

	}

	return target;

}



/* Attach the date picker to a jQuery selection.

   @param  settings  object - the new settings to use for this date picker instance (anonymous)

   @return jQuery object - for chaining further calls */

$.fn.datepicker = function(settings) {

	return this.each(function() {

		// check for settings on the control itself - in namespace 'date:'

		var inlineSettings = null;

		for (attrName in $.datepicker._defaults) {

			var attrValue = this.getAttribute('date:' + attrName);

			if (attrValue) {

				inlineSettings = inlineSettings || {};

				try {

					inlineSettings[attrName] = eval(attrValue);

				}

				catch (err) {

					inlineSettings[attrName] = attrValue;

				}

			}

		}

		var nodeName = this.nodeName.toLowerCase();

		if (nodeName == 'input') {

			var instSettings = (inlineSettings ? $.extend($.extend({}, settings || {}),

				inlineSettings || {}) : settings); // clone and customise

			var inst = (inst && !inlineSettings ? inst :

				new DatepickerInstance(instSettings, false));

			$.datepicker._connectDatepicker(this, inst);

		} 

		else if (nodeName == 'div' || nodeName == 'span') {

			var instSettings = $.extend($.extend({}, settings || {}),

				inlineSettings || {}); // clone and customise

			var inst = new DatepickerInstance(instSettings, true);

			$.datepicker._inlineDatepicker(this, inst);

		}

	});

};



/* Initialise the date picker. */

$(document).ready(function() {

	$.datepicker = new Datepicker(); // singleton instance

	$(document.body).append($.datepicker._datepickerDiv).

		mousedown($.datepicker._checkExternalClick);

});



})(jQuery);


