// Calendar: a Javascript class for Mootools that adds accessible and unobtrusive date pickers to your form elements <http://electricprism.com/aeron/calendar>
// Calendar RC4, Copyright (c) 2007 Aeron Glemann <http://electricprism.com/aeron>, MIT Style License.
// Mootools 1.2 compatibility by Davorin Šego

var Calendar = new Class({	

  Implements: Options,

	options: {
		blocked: [], // blocked dates 
		classes: [], // ['calendar', 'prev', 'next', 'month', 'year', 'today', 'invalid', 'valid', 'inactive', 'active', 'hover', 'hilite']
		direction: 0, // -1 past, 0 past + future, 1 future
		draggable: true,
		navigation: 1, // 0 = no nav; 1 = single nav for month; 2 = dual nav for month and year
		offset: 0, // first day of the week: 0 = sunday, 1 = monday, etc..
		onHideStart: Class.empty,
		onHideComplete: Class.empty,
		onShowStart: Class.empty,
		onShowComplete: Class.empty,
		pad: 1, // padding between multiple calendars
		tweak: {x: 0, y: 0} // tweak calendar positioning
	},

	// initialize: calendar constructor
	// @param obj (obj) a js object containing the form elements and format strings { id: 'format', id: 'format' etc }
	// @param props (obj) optional properties

	initialize: function(obj, options) {
		// basic error checking
		if (!obj) { return false; }

		this.setOptions(options);
                
                this.boundDockClick = this.docClick.bind(this);

		// create our classes array
		var keys = ['calendar', 'prev', 'next', 'month', 'year', 'today', 'invalid', 'valid', 'inactive', 'active', 'hover', 'hilite'];

		var values = keys.map(function(key, i) {
			if (this.options.classes[i]) {
				if (this.options.classes[i].length) { key = this.options.classes[i]; }
			}
			return key;
		}, this);

		this.classes = values.associate(keys);

		// create cal element with css styles required for proper cal functioning
		this.calendar = new Element('div', { 
			'styles': { left: '-1000px', opacity: 0, position: 'absolute', top: '-1000px', zIndex: 1000 }
		}).addClass(this.classes.calendar).injectInside(document.body);

		// iex 6 needs a transparent iframe underneath the calendar in order to not allow select elements to render through
		if (Browser.Engine.trident4) {
			this.iframe = new Element('iframe', { 
				'styles': { left: '-1000px', position: 'absolute', top: '-1000px', zIndex: 999 }
			}).injectInside(document.body);
			this.iframe.style.filter = 'progid:DXImageTransform.Microsoft.Alpha(style=0,opacity=0)';
		}

		// initialize fade method
		this.fx = new Fx.Tween(this.calendar, {
			onStart: function() { 
				if (this.calendar.getStyle('opacity') == 0) { // show
					if (Browser.Engine.trident4) { this.iframe.setStyle('display', 'block'); }
					this.calendar.setStyle('display', 'block');
					this.fireEvent('onShowStart', this.element);
				}
				else { // hide
					this.fireEvent('onHideStart', this.element);
				}
			}.bind(this),
			onComplete: function() { 
				if (this.calendar.getStyle('opacity') == 0) { // hidden
					this.calendar.setStyle('display', 'none');
					if (Browser.Engine.trident4) { this.iframe.setStyle('display', 'none'); }
					this.fireEvent('onHideComplete', this.element);
				}
				else { // shown
					this.fireEvent('onShowComplete', this.element);
				}
			}.bind(this)
		});

		// initialize drag method
		/*
		if (window.Drag && this.options.draggable) {
			this.drag = new Drag.Move(this.calendar, { 
				onDrag: function() {
					if (window.ie6) { this.iframe.setStyles({ left: this.calendar.style.left, top: this.calendar.style.top }); } 
				}.bind(this) 
			}); 
		}
	*/
		
		// create calendars array
		this.calendars = [];

		var id = 0;
		var d = new Date(); // today

		d.setDate(d.getDate() + this.options.direction.toInt()); // correct today for directional offset

                // Fix for IE adding a 1px margin to the input fields (it causes the button to be misplaced)
                var cssFix = (Browser.Engine.trident) ? 'bottom:3px' : '';

		for (var i in obj) {
			var cal = { 
				button: new Element('button', { 'type': 'button', 'style': cssFix }),
				el: $(i),
				els: [],
				id: id++,
				month: d.getMonth(),
				visible: false,
				year: d.getFullYear()
			};

			// fix for bad element (naughty, naughty element!)
			if (!this.element(i, obj[i], cal)) { continue; }
			
			cal.el.addClass(this.classes.calendar);

			// create cal button
			// cal.button.addClass(this.classes.calendar).addEvent('click', function(ev, cal) { ev.stop(); this.toggle(cal); }.bindWithEvent(this, cal)).injectAfter(cal.el);
			cal.button.addClass(this.classes.calendar).addEvent('click', this.elemClick.bind(this)).injectAfter(cal.el);
                        cal.button.cal = cal;

			// read in default value
			cal.val = this.read(cal);

			$extend(cal, this.bounds(cal)); // abs bounds of calendar

			$extend(cal, this.values(cal)); // valid days, months, years

			this.rebuild(cal);

			this.calendars.push(cal); // add to cals array		
                }
	},


	// blocked: returns an array of blocked days for the month / year
	// @param cal (obj)
	// @returns blocked days (array)

	blocked: function(cal) {
		var blocked = [];
		var offset = new Date(cal.year, cal.month, 1).getDay(); // day of the week (offset)
		var last = new Date(cal.year, cal.month + 1, 0).getDate(); // last day of this month
		
		this.options.blocked.each(function(date){
			var values = date.split(' ');
			
			// preparation
			for (var i = 0; i <= 3; i++){ 
				if (!values[i]){ values[i] = (i == 3) ? '' : '*'; } // make sure blocked date contains values for at least d, m and y
				values[i] = values[i].contains(',') ? values[i].split(',') : new Array(values[i]); // split multiple values
				var count = values[i].length - 1;
				for (var j = count; j >= 0; j--){
					if (values[i][j].contains('-')){ // a range
						var val = values[i][j].split('-');
						for (var k = val[0]; k <= val[1]; k++){
							if (!values[i].contains(k)){ values[i].push(k + ''); }
						}
						values[i].splice(j, 1);
					}
				}
			}

			// execution
			if (values[2].contains(cal.year + '') || values[2].contains('*')){
				if (values[1].contains(cal.month + 1 + '') || values[1].contains('*')){
					values[0].each(function(val){ // if blocked value indicates this month / year
						if (val > 0){ blocked.push(val.toInt()); } // add date to blocked array
					});

					if (values[3]){ // optional value for day of week
						for (var i = 0; i < last; i++){
								var day = (i + offset) % 7;
	
								if (values[3].contains(day + '')){ 
									blocked.push(i + 1); // add every date that corresponds to the blocked day of the week to the blocked array
								}
						}
					}
				}
			}
		}, this);

		return blocked;
	},


	// bounds: returns the start / end bounds of the calendar
	// @param cal (obj)
	// @returns obj	

	bounds: function(cal) {
		// 1. first we assume the calendar has no bounds (or a thousand years in either direction)
		
		// by default the calendar will accept a millennium in either direction
		var start = new Date(1000, 0, 1); // jan 1, 1000
		var end = new Date(2999, 11, 31); // dec 31, 2999

		// 2. but if the cal is one directional we adjust accordingly
		var date = new Date().getDate() + this.options.direction.toInt();

		if (this.options.direction > 0) {
			start = new Date();
			start.setDate(date + this.options.pad * cal.id);
		}
		
		if (this.options.direction < 0) {
			end = new Date();
			end.setDate(date - this.options.pad * (this.calendars.length - cal.id - 1));
		}

		// 3. then we can further filter the limits by using the pre-existing values in the selects
		cal.els.ea