/* 
Script: nogray_date.js 
	these functions will extend javascript Date object
 
License: 
	MIT-style license. 
		
provided by the NoGray.com
by Wesam Saif
support: support@nogray.com
*/ 

var _ng_date_object = {
	/*
		Variable:
			language
			
			an object that contain the language to be used in formatting
			the output from the print function
			
		Example
			alert(new Date().language.days.short[1]); // will alert Mo
	*/
	language:{
		'days':{
			'char':['S','M','T','W','T','F','S'],
			'short':['Do','Lu','Ma','Me','Gi','Ve','Sa'],
			'mid':['Dom','Lun','Mar','Mer','Gio','Ven','Sab'],
			'long':['Domenica','Lunedì','Martedì','Mercoledì','Giovedì','Venerdì','Sabato']
		},
		'months':{
			'short':['Gen','Feb','Mar','Apr','Mag','Giu','Lug','Ago','Set','Ott','Nov','Dic'],
			'long':['Gennaio','Febbraio','Marzo','Aprile','Maggio','Giugno','Luglio','Agosto','Settembre','Ottobre','Novembre','Dicembre']
		},
		'am_pm':{
			'lowerCase':['am','pm'],
			'upperCase':['AM','PM']
		}
	},
	
	/*
		Function:
			daysInMonth
		
		Returns:
			the number of days in the date month
			
		Example:
			alert(new Date(2007, 8, 1).daysInMonth());	// will alert 30 (30 days in Septembar)
	*/
	daysInMonth : function (){
		var date = new Date(this.getFullYear(), this.getMonth(), 28);
		var i = 28;
		for (i=28; i<=32; i++){
			date.setDate(i);
			if (date.getMonth() != this.getMonth())
				return (i-1);
		}
	},
	
	/*
		Function:
			isLeapYear
		
		Returns:
			Boolean. True if the yea is a leap year, false otherwise
			
		Example:
			alert(new Date(2008,0,1).isLeapYear());	// will alert true
			alert(new Date(2009,0,1).isLeapYear()); // will alert false
	*/
	isLeapYear: function (){
		var date = new Date(this.getFullYear(), 1, 29);
		return (date.getMonth() == 1);
	},
	
	/*
		Function:
			fromString
			
		Returns:
			a date object from the string provided
			
		Arguments:
			str: the string variable for the date. If the date can't be parsed using Date.parse() a list of custom values are provided below.
				All custom values are relative to the date object 
			Possible values:
			- Any string that can be parsed by Date.parse()
				* Short dates can use either a "/", "\" or "-" date separator, but must follow the month/day/year format, for example "7/20/96".
					month are 1 for January 12 for December
				* Long dates of the form "July 10 1995" can be given with the year, month, and day in any order, and the year in 2-digit or 4-digit form. If you use the 2-digit form, the year must be greater than or equal to 70. 
				* Month and day names must have two or more characters. Two character names that are not unique are resolved as the last match. For example, "Ju" is resolved as July, not June. 
				* Handles all standard time zones, as well as Universal Coordinated Time (UTC) and Greenwich Mean Time (GMT).
				* Colons separate hours, minutes, and seconds, although all need not be specified. "10:", "10:11", and "10:11:12" are all valid.
				* If the 24-hour clock is used, it is an error to specify "PM" for times later than 12 noon. For example, "23:15 PM" is an error. 
				* A string containing an invalid date is an error. For example, a string containing two years or two months is an error. 
			- "yesterday" a day before relative to the date object
			- "tomorrow" a day after relative to the date object
			- "today+[n]" [n] is any number
				add the [n] number of days to the date
			- "today-[n]" [n] is any number
				subtract the [n] number of days from the date
			- "last month" a month before relative to the date object
			- "next month" a month after relative to the date object
			- "month+[n]" [n] is any number
				add the [n] number of months to the date
			- "month-[n]" [n] is any number
				subtract the [n] number of days from the date
			- "last year"
			- "next year"
			- "year+[n]"
			- "year-[n]"
			
		Example:
			alert(new Date().fromString("yesterday"));	// will alert yesterday's day

	*/
	fromString: function(str){
		var prs_dt = Date.parse(str.replace(/[-|\\]/g,"/"));
		
		if (isNaN(prs_dt)){
			str = str.toLowerCase();
			str = str.replace(/(\s)*([\+|-])(\s)*/g, "$2");
			
			var y = this.getFullYear();
			var m = this.getMonth();
			var d = this.getDate();
			
			str = str.replace("yesterday", "today-1")
					.replace("tomorrow", "today+1")
					.replace("last month", "month-1")
					.replace("next month", "month+1")
					.replace("last year", "year-1")
					.replace("next year", "year+1");
			
			if(str.indexOf("today+") >= 0)
				d = d+str.replace("today+","").toInt();
			else if(str.indexOf("today-") >= 0)
				d = d-str.replace("today-","").toInt();
			else if(str.indexOf("month+") >= 0){
				m = m+str.replace("month+","").toInt();
				var mx_dys = new Date(y, m, 1).daysInMonth();
				if (d > mx_dys) d = mx_dys;
			}
			else if(str.indexOf("month-") >= 0){
				m = this.getMonth()-str.replace("month-","").toInt();
				var mx_dys = new Date(y, m, 1).daysInMonth();
				if (d > mx_dys) d = mx_dys;
			}
			else if(str.indexOf("year+") >= 0){
				y = y+str.replace("year+","").toInt();
				var mx_dys = new Date(y, m, 1).daysInMonth();
				if (d > mx_dys) d = mx_dys;
			}
			else if(str.indexOf("year-") >= 0){
				y = this.getFullYear()-str.replace("year-","").toInt();
				var mx_dys = new Date(y, m, 1).daysInMonth();
				if (d > mx_dys) d = mx_dys;
			}
			
			var dt = new Date(y, m, d, this.getHours(), this.getMinutes(), this.getSeconds(), this.getMilliseconds());
		}
		else {
			var dt = new Date(prs_dt);	
		}
		
		return dt;
	},
	
	/*
		Function:
			fromObject
			
		Returns:
			a date from the object provided
			
		Arguments:
			date_obj: an object that hold the date values
				the date_obj should have the following attributes
				
				- date: can be either a number or a string
					if string, the following values are allowed
					* "[1st | 2nd | 3rd | 4th | 5th | last] sunday" either the 1st, 2nd, or 3rd, etc... sunday of the month.
						will return the date for the [nth] or last sunday of the month
					* "[1st | 2nd | 3rd | 4th | 5th | last] monday" same as above but for monday
					* "[1st | 2nd | 3rd | 4th | 5th | last] tuesday"
					* "[1st | 2nd | 3rd | 4th | 5th | last] wednesday"
					* "[1st | 2nd | 3rd | 4th | 5th | last] thursday"
					* "[1st | 2nd | 3rd | 4th | 5th | last] friday"
					* "[1st | 2nd | 3rd | 4th | 5th | last] saturday"
				- month: a numerical value for the month
						0 for January 11 for December
				- year: a numerical value for the year (for digits format)
				- hour: a numerical value for the hour
				- minute: a numerical value for the minute
				- second: a numerical value for the second
				- millisecond: a numerical value for the millisecond
				
				if any of the values above is not defined, the current date value will be used.
				
			Example:
				alert(new Date(2007,8,1).fromObject({'date':'last friday'}));	// will alert the date for Sep 28th 2007
				alert(new Date(2007,8,1).fromObject({'date':'3rd Monday'}));	// will alert the date for Sep 17th 2007
					
	*/
	fromObject: function(date_obj){
		var obj = {};
		var p;
		for (p in date_obj)
			obj[p] = date_obj[p];
			
		
		if (!$defined(obj.date)) obj.date = this.getDate();
		if (!$defined(obj.month)) obj.month = this.getMonth();
		if (!$defined(obj.year)) obj.year = this.getFullYear();
		if (!$defined(obj.hour)) obj.hour = this.getHours();
		if (!$defined(obj.minute)) obj.minute = this.getMinutes();
		if (!$defined(obj.second)) obj.second = this.getSeconds();
		if (!$defined(obj.millisecond)) obj.millisecond = this.getMilliseconds();
				
		if ($type(obj.date) != "string"){
			var dt = new Date(obj.year, obj.month ,obj.date, obj.hour, obj.minute, obj.second, obj.millisecond);
			return dt;
		}
		
		obj.date = obj.date.toLowerCase();
		var date = new Date(obj.year, obj.month, 1);

		var cur_dy;
		if (obj.date.indexOf("sunday") != -1)
			cur_dy = 0;
		else if (obj.date.indexOf("monday") != -1)
			cur_dy = 1;
		else if (obj.date.indexOf("tuesday") != -1)
			cur_dy = 2;
		else if (obj.date.indexOf("wednesday") != -1)
			cur_dy = 3;
		else if (obj.date.indexOf("thursday") != -1)
			cur_dy = 4;
		else if (obj.date.indexOf("friday") != -1)
			cur_dy = 5;
		else if (obj.date.indexOf("saturday") != -1)
			cur_dy = 6;
			
		
		if (date.getDay() > cur_dy)
			var fd = (7 - date.getDay()) + cur_dy + 1;
		else if (date.getDay() < cur_dy)
			var fd = cur_dy -  date.getDay() + 1;
		else
			var fd = 1;
						
		var rp_arr = ["1st","2nd","3rd","4th","5th"];
		var c=5;
		var dnm = date.daysInMonth();
		while(obj.date.indexOf("last") != -1){
			if ((fd+(c*7)) <= dnm)
				obj.date = obj.date.replace("last",rp_arr[c]);
			c--;
			if (c < 0)
				obj.date = obj.date.replace("last","1st");
		}
		
		var after_dys;
		if (obj.date.indexOf("1st") != -1)
			after_dys = 0;
		else if (obj.date.indexOf("2nd") != -1)
			after_dys = 1;
		else if (obj.date.indexOf("3rd") != -1)
			after_dys = 2;
		else if (obj.date.indexOf("4th") != -1)
			after_dys = 3; 
		else if (obj.date.indexOf("5th") != -1)
			after_dys = 4;
		
		var dt = new Date(obj.year, obj.month, fd+(after_dys*7), obj.hour, obj.minute, obj.second, obj.millisecond);
		return dt;
	},
	
	/*
		Function:
			print
		
		Returns:
			a formatted date string similar to PHP date function
			
		Arguments:
			format: a string to format the return value from the date
				Please visit http://us.php.net/manual/en/function.date.php for more details
				on the possible values
				
				the only exception is the Y and o will return the same value
				
			lang:
				a language object if using a different language than the date object
				
		Example:
			alert(new Date(2007,8,12).print("D, d M Y")); // will alert Wed, 12 Sep 2007
				
	*/
	print: function(format, lang){
		if (!$defined(lang)) lang = this.language;
		else {
			if ($defined(lang.days)){
				if (!$defined(lang.days['char'])) lang.day['char'] = this.language.days['char'];
				if (!$defined(lang.days['short'])) lang.day['short'] = this.language.days['short'];
				if (!$defined(lang.days['mid'])) lang.day['mid'] = this.language.days['mid'];
				if (!$defined(lang.days['long'])) lang.day['long'] = this.language.days['long'];
			}
			else
				lang.days = this.language.days;
			
			if ($defined(lang.months)){
				if (!$defined(lang.months['short'])) lang.months['short'] = this.language.months['short'];
				if (!$defined(lang.months['long'])) lang.months['long'] = this.language.months['long'];
			}
			else
				lang.months = this.language.months;
				
			if ($defined(lang.am_pm)){
				if (!$defined(lang.am_pm['lowerCase'])) lang.am_pm['lowerCase'] = this.language.am_pm['lowerCase'];
				if (!$defined(lang.am_pm['upperCase'])) lang.am_pm['upperCase'] = this.language.am_pm['upperCase'];
			}
			else
				lang.am_pm = this.language.am_pm;
		}
		var i=0;
		var re = "";
		var ch = "";
		
		for (i=0; i<format.length; i++){
			ch = format.charAt(i);
			if (ch == "d"){
				if (this.getDate() < 10) re += "0";
				re += this.getDate();
			}
			else if (ch == "D")
				re += lang.days['mid'][this.getDay()];
			else if (ch == "j")
				re += day;
			else if (ch == "l")
				re += lang.days['long'][this.getDay()];
			else if (ch == "N"){
				var num = this.getDay();
				if (num == 0) num = 7;
				re += num;
			}
			else if (ch == "S"){
				if ((this.getDate() == "1") || (this.getDate() == "21") || (this.getDate() == "31"))
					re += "st";
				else if ((this.getDate() == "2") || (this.getDate() == "22"))
					re += "nd";
				else if ((this.getDate() == "3") || (this.getDate() == "23"))
					re += "rd";
				else
					re += "th";
			}
			else if (ch == "w")
				re += this.getDay();
			else if (ch == "z")
				re += this.getDayInYear();
			else if (ch == "F")
				re += lang.months['long'][this.getMonth()];
			else if (ch == "M")
				re += lang.months['short'][this.getMonth()];
			else if (ch == "m"){
				if (this.getMonth()+1 < 10) re += 0;
				re += this.getMonth()+1;
			}
			else if (ch == "n")
				re += this.getMonth();
			else if (ch == "t")
				re += this.daysInMonth();
			else if (ch == "L"){
				if (this.isLeapYear())
					re += 1;
				else
					re += 0;
			}
			else if ((ch == "Y") || (ch == "o"))
				re += this.getFullYear();
			else if (ch == "y")
				re += this.getFullYear().toString().substr(2,2);
				
			else if (ch == "a"){
				if (this.getHours() < 12)
					re += lang.am_pm['lowerCase'][0];
				else
					re += lang.am_pm['lowerCase'][1];
			}
			else if (ch == "A"){
				if (this.getHours() < 12)
					re += lang.am_pm['upperCase'][0];
				else
					re += lang.am_pm['upperCase'][1];
			}
			else if (ch == "B")
				re += this.toSwatchInternetTime();
			else if (ch == "g"){
				var hr = (this.getHours()%12);
				if (hr == 0) hr = 12;
				re += hr;
			}
			else if (ch == "G")
				re += this.getHours();
			else if (ch == "h"){
				var hr = (this.getHours()%12);
				if (hr == 0) hr = 12;
				if (h < 10) r += 0;
				re += hr;
			}
			else if (ch == "H"){
				if (this.getHours() < 10) re += 0;
				re += this.getHours();
			}
			else if (ch == "i"){
				if (this.getMinutes() < 10) re += 0;
				re += this.getMinutes();
			}
			else if (ch == "s"){
				if (this.getSeconds() < 10) re += 0;
				re += this.getSeconds();
			}
			else if (ch == "u")
				re += this.getMilliseconds();
			else if ((ch == "O") || (ch == "P")){
				var hr = (this.getTimezoneOffset())/60;
				var mn = hr - Math.floor(hr);
				mn = mn*60;
				hr = Math.floor(hr);
				mn = Math.floor(mn);
				if (hr == 0) hr = "00";
				else if ((hr > -10) && (hr < 0)) hr = "-0"+Math.abs(hr); 
				else if ((hr < 10) && (hr > 0)) hr = "0"+hr;
				else hr = hr.toString();
				if (hr > 0) re += "+";
				if (mn < 10) mn = "0"+mn;
				else mn = mn.toString();
				if (ch == "P") var sep = ":";
				else var sep = "";
				re += hr+sep+mn;
			}
			else if (ch == "Z")
				re += this.getTimezoneOffset();
			else if (ch == "c"){
				format = format.substr(0, i-0)+"Y-m-dTH:i:sP"+format.substr(0, i);
				i--;
			}
			else if (ch == "r"){
				format = format.substr(0, i-0)+"D, d M Y H:i:s O"+format.substr(0, i);
				i--;
			}
			else if (ch == "U")
				re += Math.floor(this.timeDifference(new Date(1970,0,1))/1000);
			else
				re += ch;
				
		}
		
		return re;	
	},
	
	
	/*
		Function:
			getWeekInYear
		
		Returns:
			the number of week in the year
			
		Example:
			alert(new Date(2007,8,12).getWeekInYear());	// will alert 36
	*/
	getWeekInYear: function(){
		return Math.floor(this.getDayInYear()/7);	
	},
	
	/*
		Function:
			getDayInYear
		
		Returns:
			the number of day in the year
			
		Example:
			alert(new Date(2007,8,12).getDayInYear());	// will alert 253
	*/
	
	getDayInYear: function(){
		return Math.floor(this.getHourInYear()/24);	
	},
	
	getHourInYear: function(){
		return Math.floor(this.getMinuteInYear()/60);
	},
	
	getMinuteInYear: function(){
		return Math.floor(this.getSecondInYear()/60);
	},
	
	getSecondInYear: function(){
		return Math.floor(this.getMillisecondInYear()/1000);
	},
	
	
	getMillisecondInYear: function(){
		return this.timeDifference(new Date(this.getFullYear(), 0, 1));
	},
	
	/*
		Function:
			getWeekSince
		
		Returns:
			the number of week since a given date
			
		Arguments:
			date: a javascript date object
			
		Example:
			alert(new Date(2007,8,12).getWeekSince(new Date(2006,2,14)));	// will alert 78
	*/
	
	getWeekSince: function(date){
		return Math.floor(this.getDaySince(date)/7);	
	},
	
	
	/*
		Function:
			getDaySince
		
		Returns:
			the number of days since a given date
			
		Arguments:
			date: a javascript date object
			
		Example:
			alert(new Date(2007,8,12).getDaySince(new Date(2006,2,14)));	// will alert 547
	*/
	
	getDaySince: function(date){
		return Math.floor(this.getHourSince(date)/24);	
	},
	
	getHourSince: function(date){
		return Math.floor(this.getMinuteSince(date)/60);
	},
	
	getMinuteSince: function(date){
		return Math.floor(this.getSecondSince(date)/60);
	},
	
	getSecondSince: function(date){
		return Math.floor(this.getMillisecondSince(date)/1000);
	},
	
	getMillisecondSince: function(date){
		return this.timeDifference(date);
	},
	
	
	/*
		Function:
			timeDifference
			
		Returns:
			return the time difference in milliseconds between the date and the arguments date
			
		Arguments:
			date: javascript date
			
		Example:
			alert(new Date(2007,8,12).timeDifference(new Date(2006,2,14))); // will alert 47260800000
	*/
	timeDifference: function(date){
		return this.getTime() - date.getTime();	
	},
	
	/*
		Function:
			toSwatchInternetTime
			for more details about the Swatch Internet Time, please visit http://www.swatch.com/internettime/
			
		Returns:
			the number of beats as a string (including the @ sign)
			This function assume the browser handles the time zone and day time saving
			
		Example:
			alert(new Date(2007,8,12,8,52,0).toSwatchInternetTime()); // will alert @702 (based on timezone)
		
	*/
	
	
	toSwatchInternetTime: function(){
		var sec = (this.getHours() * 3600) + (this.getMinutes() * 60) + this.getSeconds() + ((this.getTimezoneOffset() + 60)*60);
		var beat = Math.floor(sec/86.4);
		return ("@"+beat);
	},
	
	/*
		Function:
			fromSwatchInternetTime
			for more details about the Swatch Internet Time, please visit http://www.swatch.com/internettime/
			
		Returns:
			a javascript date object (approximate time)
			This function assume the browser handles the time zone and day time saving
			
		Arguments:
			beat: the beat value
			
		Example:
			alert(new Date().fromSwatchInternetTime(354)); // will alert the time at 10:47:31 (based on timezone)
	*/
	
	fromSwatchInternetTime: function (beat){
		if ($type(beat) == "string") beat = beat.replace("@","").toInt();
		var sec = Math.floor(beat*86.4) - ((this.getTimezoneOffset() + 60)*60);
				
		var dt = new Date(this.getFullYear(), this.getMonth(), this.getDate());
		dt.setTime(dt.getTime()+(sec*1000));
		
		return dt;
	}
	
	
};

try {
	$native(Date);
	Date.extend(_ng_date_object);
}
catch(e) {
	Native.implement([Date], _ng_date_object);	
}

delete _ng_date_object;