/*
bam.dateSelector version 2.02
Requires jQuery for DOM operations.

Aleksandar Kolundzija
*/

bam.extend({
					 
	dateSelector: (function(){
		
		var _dateLimits = {start:null, end:null};
					
		var _self = {

			divId : "dateSelector",
			$elem : null,
			
			month : null,
			year  : null,
			today : null,
			
			showResetLink: true,
			
			curDateField: null, // reference to currently selected "date" form field
			
			months:   {"1":"January", "2":"February", "3":"March", "4":"April", "5":"May", "6":"June", "7":"July", "8":"August", "9":"September", "10":"October", "11":"November", "12":"December"},
			weekdays: ["Sun","Mon","Tue","Wed","Thu","Fri","Sat"],
			selectedDates: [],
			
			existsInDom: function(){
				return ($("#"+_self.divId).length);
			},		
			
			appendToDom: function(){
				$("<div id='"+_self.divId+"'></div>").appendTo("body"); 
				_self.$elem = $("#"+_self.divId);
			},
			
			setMonthAndYear: function(month,year){
				var today   = new Date();
				_self.month = (month!=null && month>0 && month<13) ? month : today.getMonth()+1;
				_self.year  = year || today.getFullYear();
			},
	
			setToday: function(today){
				_self.today = today;
			},
			
			setDateLimits: function(startDate, endDate){
				_dateLimits.start = startDate || _dateLimits.start;
				_dateLimits.end   = endDate   || _dateLimits.end;
			},
			
			show: function(month,year){
				if (!_self.existsInDom()){ _self.appendToDom(); }
				_self.setMonthAndYear(month,year);
				_self.$elem.html(_self.getCalendarHtml()).fadeIn("fast");
				_self.highlightSelectedDays();
			},
			
			hide: function(){
				_self.$elem.fadeOut("fast");
			},
			
			toggle: function(){
				_self.$elem.toggle();
			},
			
			reset: function(){
				_self.selectedDates = [];
				_self.show();
			},
			
			addDate: function(date){
				_self.selectedDates.push(date);
			},
			
			removeDate: function(date){
				var remainingDates = [];
				$.each(_self.selectedDates, function(i,n){
					if (_self.selectedDates[i] != date) remainingDates.push(_self.selectedDates[i]);
				});
				_self.selectedDates = remainingDates;
			},
			
			highlightSelectedDays: function(){
				$.each(_self.selectedDates, function(i,n){
					if (_self.getTwoDigit(_self.month) == _self.selectedDates[i].substr(4,2) && _self.year == _self.selectedDates[i].substr(0,4)){
						_self.toggleCell("cell" + _self.selectedDates[i].substr(6,2),_self.selectedDates[i],true);
					}
				});
			},
			
			getDaysInMonth: function(){
				var month = arguments[0] || _self.month-1;
				return 32 - new Date(_self.year, month, 32).getDate();
			},
			
			getWeekdayIndexFirstOfMonth: function(){
				var firstOfMonth = new Date(_self.year, _self.month-1, 1);
				return firstOfMonth.getDay();
			},
			
			getTwoDigit: function(num){
				num = num.toString();
				if (num.length == 2) return num;
				else return "0" + num;
			},
			
			removeLeadingZero: function(num){
				var numStr = num.toString();
				if (numStr.charAt(0) == 0) return numStr.charAt(1);
				else return numStr;
			},

			/* expects dateVal in form YYYYMMDD */
			getDateObj: function(dateVal){
				if (!dateVal) return false;
				dateVal   = dateVal.toString();
				var year  = dateVal.substr(0,4);
				var month = _self.removeLeadingZero(dateVal.substr(4,2));
				var day   = _self.removeLeadingZero(dateVal.substr(6,2));
				return new Date(year,(month-1),day);
			},
			
			/* expects dateVal in form YYYYMMDD */
			getDateString: function(dateVal, customFunction){
				var date = _self.getDateObj(dateVal);
				if (date){
					if (customFunction){ return date['customFunction'].apply(null,[]); }
					return date.toDateString();
				}
			},
			
			getMonthName: function(){
				var month = _self.month.toString();
				if (month.charAt(0) == 0) {
					return _self.months[month.charAt(1)];
				}
				else {
					return _self.months[month];
				}
			},
			
			getPrevMonthLink: function(){
				var prevMonth, year;
				if (_self.month == 1){
					prevMonth = 12; 
					year      = _self.year-1;
				}
				else {
					prevMonth = _self.month-1;
					year      = _self.year;
				}
				return "<a href='javascript:void(0)' onclick='bam.dateSelector.show(" + prevMonth + "," + year + ")'>" + "&laquo; Prev" + "</a>";
			},
			
			getNextMonthLink: function(){
				var nextMonth, year;
				if (_self.month == 12){
					nextMonth = 1; 
					year = _self.year+1;
				} 
				else { 
					nextMonth = _self.month+1; 
					year = _self.year;
				}
				return "<a href='javascript:void(0)' onclick='bam.dateSelector.show(" + nextMonth + "," + year + ")'>" + "Next &raquo;" + "</a>";
			},
			
			isToday: function(curDate){
				return (_self.today != null && curDate == _self.today);
			},
			
			getCalendarHtml: function(){
				
				var curDay        = 1;
				var curDate       = null;
				var weekdayIndex  = _self.getWeekdayIndexFirstOfMonth();
				var isFirstWeek   = true;
				var isDateInRange = true;
				
				var out = "\
					<table id='monthNav'>\
					<tr>\
						<td class='monthLink'>" + _self.getPrevMonthLink() + "</td>\
						<td class='curMonth'>" + _self.getMonthName() + " " + _self.year + "</div>\
						<td class='monthLink' align='right'>" + _self.getNextMonthLink() + "</td>\
					</tr>\
					</table>\
					<table id='monthDays' cellspacing='1'>\
					<thead><tr>";
					
				for (var i=0; i<_self.weekdays.length; i++) out += "<td>" + _self.weekdays[i] + "</td>\n";
				out += "</tr></thead><tbody>\n";
							
				while (curDay <= _self.getDaysInMonth()){
					// draw blank days in first week
					if (isFirstWeek && weekdayIndex != 0){
						out += "<tr>";
						for (var i=1; i<=weekdayIndex; i++){ out += "<td class='blank'>&nbsp;</td>\n"; }
						isFirstWeek = false;
					}
					else {
						isFirstWeek = false;
					}
			
					if (weekdayIndex==0) out += "<tr>\n"; // if weekday is Sunday, open new table row
					out += "<td id='cell"+_self.getTwoDigit(curDay)+"' class='day"+(( _self.isToday(_self.year + _self.getTwoDigit(_self.month) + _self.getTwoDigit(curDay)) )?" today":"")+"'>";
					
					curDate = new Date(_self.year, _self.month-1, curDay);
					
					isDateInRange = (_dateLimits.start) ? (curDate >= _dateLimits.start) : isDateInRange; // if start date is set, check if curDate is after it
					isDateInRange = (_dateLimits.end)   ? (curDate <= _dateLimits.end)   : isDateInRange; // if end date is set, check if curDate is before it
					isDateInRange = (_dateLimits.start && _dateLimits.end) ? (curDate >= _dateLimits.start && _dateLimits.end) : isDateInRange; // if range is set, check if curDate is within it
					
					if (isDateInRange){
						out += "<a href='javascript:void(0)' onclick=\"bam.dateSelector.toggleCell('cell"+_self.getTwoDigit(curDay)+"','"+_self.year+_self.getTwoDigit(_self.month)+_self.getTwoDigit(curDay)+"',false); this.blur();\">" + curDay + "</a>";
					}
					else {
						out += "<div class=\"outOfRange\">" + curDay + "</div>";
					}

					out += "</td>";
					if (weekdayIndex==6) out += "</tr>\n"; // if weekday is Saturday, close table row
			
					weekdayIndex++;
					weekdayIndex = weekdayIndex % 7;
					curDay++;
				}
				
				// draw blank days in last week
				while (weekdayIndex < 7 && weekdayIndex != 0){
					out += "<td class='blank'>&nbsp;</td>\n";
					weekdayIndex++;
				}
				out += "</tr></tbody></table>\n";
				
				out += "<table id='subLinks'>\n";
				out += "<tr><td>";
				if (_self.showResetLink) { out += "<a href='javascript:bam.dateSelector.reset()'>Reset</a>"; }
				out += "</td><td align='right'><a href='javascript:bam.dateSelector.hide()'>Close</a></td></tr>\n";
				out += "</table>\n";
				return out;
			},
			
			toggleCell: function(cellId,dateString,onlyChangeCellColor){
				var cell = $("#"+cellId);
				if (cell.attr("class") == "day" || cell.attr("class") == "day today"){
					cell.attr("class","selectedDay");
					if (!onlyChangeCellColor){
						_self.addDate(dateString);
					}
				}
				else {
					cell.attr("class","day");
					if (!onlyChangeCellColor) _self.removeDate(dateString);
				}
				if (!onlyChangeCellColor) _self.processSelection();
			},
			
			processSelection: function(){
				// override this method for actual response
				alert("bam.dateSelector.processSelection() hasn't been re-defined as needed.");
			}
		}
		
		return _self;	
	
	})()
	
});