add strftime implementation

lib/prettydate.js

@@ -0,0 +1,2 @@
+exports.strftime = strftime = require('./strftime');
+

lib/strftime.js

@@ -0,0 +1,322 @@
+/**
+ * strftime formatters for javascript based on the Open Group specification defined at
+ * http://www.opengroup.org/onlinepubs/007908799/xsh/strftime.html
+ * This implementation does not include modified conversion specifiers (i.e., Ex and Ox)
+ */
+
+/**
+ * Pad a number with leading spaces, zeroes or something else
+ * @method xPad
+ * @param x {Number}	The number to be padded
+ * @param pad {String}  The character to pad the number with
+ * @param r {Number}	(optional) The base of the pad, eg, 10 implies to two digits, 100 implies to 3 digits.
+ * @private
+ */
+function xPad(x, pad, r)
+{
+	if(typeof r === "undefined") {
+		r=10;
+	}
+	pad = pad.toString();
+	for( ; parseInt(x, 10)<r && r>1; r/=10) {
+		x = pad + x;
+	}
+	return x.toString();
+}
+
+var formats = {
+	a: function (d, l) { return l.a[d.getDay()]; },
+	A: function (d, l) { return l.A[d.getDay()]; },
+	b: function (d, l) { return l.b[d.getMonth()]; },
+	B: function (d, l) { return l.B[d.getMonth()]; },
+	C: function (d) { return xPad(parseInt(d.getFullYear()/100, 10), 0); },
+	d: ["getDate", "0"],
+	e: ["getDate", " "],
+	g: function (d) { return xPad(parseInt(formats.G(d)%100, 10), 0); },
+	G: function (d) {
+			var y = d.getFullYear();
+			var V = parseInt(formats.V(d), 10);
+			var W = parseInt(formats.W(d), 10);
+
+			if(W > V) {
+				y++;
+			} else if(W===0 && V>=52) {
+				y--;
+			}
+
+			return y;
+		},
+	H: ["getHours", "0"],
+	I: function (d) { var I=d.getHours()%12; return xPad(I===0?12:I, 0); },
+	j: function (d) {
+			var gmd_1 = new Date("" + d.getFullYear() + "/1/1 GMT");
+			var gmdate = new Date("" + d.getFullYear() + "/" + (d.getMonth()+1) + "/" + d.getDate() + " GMT");
+			var ms = gmdate - gmd_1;
+			var doy = parseInt(ms/60000/60/24, 10)+1;
+			return xPad(doy, 0, 100);
+		},
+	k: ["getHours", " "],
+	l: function (d) { var I=d.getHours()%12; return xPad(I===0?12:I, " "); },
+	m: function (d) { return xPad(d.getMonth()+1, 0); },
+	M: ["getMinutes", "0"],
+	p: function (d, l) { return l.p[d.getHours() >= 12 ? 1 : 0 ]; },
+	P: function (d, l) { return l.P[d.getHours() >= 12 ? 1 : 0 ]; },
+	s: function (d, l) { return parseInt(d.getTime()/1000, 10); },
+	S: ["getSeconds", "0"],
+	u: function (d) { var dow = d.getDay(); return dow===0?7:dow; },
+	U: function (d) {
+			var doy = parseInt(formats.j(d), 10);
+			var rdow = 6-d.getDay();
+			var woy = parseInt((doy+rdow)/7, 10);
+			return xPad(woy, 0);
+		},
+	V: function (d) {
+			var woy = parseInt(formats.W(d), 10);
+			var dow1_1 = (new Date("" + d.getFullYear() + "/1/1")).getDay();
+			// First week is 01 and not 00 as in the case of %U and %W,
+			// so we add 1 to the final result except if day 1 of the year
+			// is a Monday (then %W returns 01).
+			// We also need to subtract 1 if the day 1 of the year is 
+			// Friday-Sunday, so the resulting equation becomes:
+			var idow = woy + (dow1_1 > 4 || dow1_1 <= 1 ? 0 : 1);
+			if(idow === 53 && (new Date("" + d.getFullYear() + "/12/31")).getDay() < 4)
+			{
+				idow = 1;
+			}
+			else if(idow === 0)
+			{
+				idow = formats.V(new Date("" + (d.getFullYear()-1) + "/12/31"));
+			}
+
+			return xPad(idow, 0);
+		},
+	w: "getDay",
+	W: function (d) {
+			var doy = parseInt(formats.j(d), 10);
+			var rdow = 7-formats.u(d);
+			var woy = parseInt((doy+rdow)/7, 10);
+			return xPad(woy, 0, 10);
+		},
+	y: function (d) { return xPad(d.getFullYear()%100, 0); },
+	Y: "getFullYear",
+	z: function (d) {
+			var o = d.getTimezoneOffset();
+			var H = xPad(parseInt(Math.abs(o/60), 10), 0);
+			var M = xPad(Math.abs(o%60), 0);
+			return (o>0?"-":"+") + H + M;
+		},
+	Z: function (d) {
+		var tz = d.toString().replace(/^.*:\d\d( GMT[+-]\d+)? \(?([A-Za-z ]+)\)?\d*$/, "$2").replace(/[a-z ]/g, "");
+		if(tz.length > 4) {
+			tz = formats.z(d);
+		}
+		return tz;
+	},
+	"%": function (d) { return "%"; }
+};
+
+var aggregates = {
+	c: "locale",
+	D: "%m/%d/%y",
+	F: "%Y-%m-%d",
+	h: "%b",
+	n: "\n",
+	r: "%I:%M:%S %p",
+	R: "%H:%M",
+	t: "\t",
+	T: "%H:%M:%S",
+	x: "locale",
+	X: "locale"
+	//"+": "%a %b %e %T %Z %Y"
+};
+
+/**
+ * Takes a native JavaScript Date and formats it as a string for display to user.
+ *
+ * @method strftime
+ * @param oDate {Date} Date.
+ * @param sFormat {Object} (Required) Format specifier
+ *   <p>
+ *   Any strftime string is supported, such as "%I:%M:%S %p". strftime has several format specifiers defined by the Open group at 
+ *   <a href="http://www.opengroup.org/onlinepubs/007908799/xsh/strftime.html">http://www.opengroup.org/onlinepubs/007908799/xsh/strftime.html</a>
+ *   PHP added a few of its own, defined at <a href="http://www.php.net/strftime">http://www.php.net/strftime</a>
+ *   </p>
+ *   <p>
+ *   This javascript implementation supports all the PHP specifiers and a few more.  The full list is below.
+ *   </p>
+ *   <dl>
+ *	<dt>%a</dt> <dd>abbreviated weekday name according to the current locale</dd>
+ *	<dt>%A</dt> <dd>full weekday name according to the current locale</dd>
+ *	<dt>%b</dt> <dd>abbreviated month name according to the current locale</dd>
+ *	<dt>%B</dt> <dd>full month name according to the current locale</dd>
+ *	<dt>%c</dt> <dd>preferred date and time representation for the current locale</dd>
+ *	<dt>%C</dt> <dd>century number (the year divided by 100 and truncated to an integer, range 00 to 99)</dd>
+ *	<dt>%d</dt> <dd>day of the month as a decimal number (range 01 to 31)</dd>
+ *	<dt>%D</dt> <dd>same as %m/%d/%y</dd>
+ *	<dt>%e</dt> <dd>day of the month as a decimal number, a single digit is preceded by a space (range " 1" to "31")</dd>
+ *	<dt>%F</dt> <dd>same as %Y-%m-%d (ISO 8601 date format)</dd>
+ *	<dt>%g</dt> <dd>like %G, but without the century</dd>
+ *	<dt>%G</dt> <dd>The 4-digit year corresponding to the ISO week number</dd>
+ *	<dt>%h</dt> <dd>same as %b</dd>
+ *	<dt>%H</dt> <dd>hour as a decimal number using a 24-hour clock (range 00 to 23)</dd>
+ *	<dt>%I</dt> <dd>hour as a decimal number using a 12-hour clock (range 01 to 12)</dd>
+ *	<dt>%j</dt> <dd>day of the year as a decimal number (range 001 to 366)</dd>
+ *	<dt>%k</dt> <dd>hour as a decimal number using a 24-hour clock (range 0 to 23); single digits are preceded by a blank. (See also %H.)</dd>
+ *	<dt>%l</dt> <dd>hour as a decimal number using a 12-hour clock (range 1 to 12); single digits are preceded by a blank. (See also %I.) </dd>
+ *	<dt>%m</dt> <dd>month as a decimal number (range 01 to 12)</dd>
+ *	<dt>%M</dt> <dd>minute as a decimal number</dd>
+ *	<dt>%n</dt> <dd>newline character</dd>
+ *	<dt>%p</dt> <dd>either "AM" or "PM" according to the given time value, or the corresponding strings for the current locale</dd>
+ *	<dt>%P</dt> <dd>like %p, but lower case</dd>
+ *	<dt>%r</dt> <dd>time in a.m. and p.m. notation equal to %I:%M:%S %p</dd>
+ *	<dt>%R</dt> <dd>time in 24 hour notation equal to %H:%M</dd>
+ *	<dt>%s</dt> <dd>number of seconds since the Epoch, ie, since 1970-01-01 00:00:00 UTC</dd>
+ *	<dt>%S</dt> <dd>second as a decimal number</dd>
+ *	<dt>%t</dt> <dd>tab character</dd>
+ *	<dt>%T</dt> <dd>current time, equal to %H:%M:%S</dd>
+ *	<dt>%u</dt> <dd>weekday as a decimal number [1,7], with 1 representing Monday</dd>
+ *	<dt>%U</dt> <dd>week number of the current year as a decimal number, starting with the
+ *			first Sunday as the first day of the first week</dd>
+ *	<dt>%V</dt> <dd>The ISO 8601:1988 week number of the current year as a decimal number,
+ *			range 01 to 53, where week 1 is the first week that has at least 4 days
+ *			in the current year, and with Monday as the first day of the week.</dd>
+ *	<dt>%w</dt> <dd>day of the week as a decimal, Sunday being 0</dd>
+ *	<dt>%W</dt> <dd>week number of the current year as a decimal number, starting with the
+ *			first Monday as the first day of the first week</dd>
+ *	<dt>%x</dt> <dd>preferred date representation for the current locale without the time</dd>
+ *	<dt>%X</dt> <dd>preferred time representation for the current locale without the date</dd>
+ *	<dt>%y</dt> <dd>year as a decimal number without a century (range 00 to 99)</dd>
+ *	<dt>%Y</dt> <dd>year as a decimal number including the century</dd>
+ *	<dt>%z</dt> <dd>numerical time zone representation</dd>
+ *	<dt>%Z</dt> <dd>time zone name or abbreviation</dd>
+ *	<dt>%%</dt> <dd>a literal "%" character</dd>
+ *   </dl>
+ *  @param sLocale {String} (Optional)</dt>
+ *   The locale to use when displaying days of week, months of the year, and other locale specific
+ *   strings. If not specified, this defaults to "en" (though this may be overridden by the deprecated Y.config.locale).
+ *   The following locales are built in:
+ *   <dl>
+ *    <dt>en</dt>
+ *    <dd>English</dd>
+ *    <dt>en-US</dt>
+ *    <dd>US English</dd>
+ *    <dt>en-GB</dt>
+ *    <dd>British English</dd>
+ *    <dt>en-AU</dt>
+ *    <dd>Australian English (identical to British English)</dd>
+ *   </dl>
+ * @return {String} Formatted date for display.
+ */
+function strftime(oDate, sFormat, sLocale) {
+	var locale;
+
+	if(!oDate) {
+		return "";
+	}
+
+	if(!sFormat) {
+		sFormat="";
+	}
+
+	if(!sLocale) {
+		sLocale = 'en-US';
+	}
+
+	sLocale = sLocale.replace(/_/g, "-");
+
+	// Make sure we have a definition for the requested locale, or default to en.
+	if(!LOCALES[sLocale]) {
+		console.warn("selected locale " + sLocale + " not found, trying alternatives");
+		var tmpLocale = sLocale.replace(/-[a-zA-Z]+$/, "");
+		if(tmpLocale in LOCALES) {
+			sLocale = tmpLocale;
+		} else {
+			sLocale = "en";
+		}
+		console.info("falling back to " + sLocale);
+	}
+
+	locale = LOCALES[sLocale];
+
+	var replace_aggs = function (m0, m1) {
+		var f = aggregates[m1];
+		return (f === "locale" ? locale[m1] : f);
+	};
+
+	var replace_formats = function (m0, m1) {
+		var f = formats[m1];
+		if(typeof f == 'string')					// string => built in date function
+			return oDate[f]();
+		else if(typeof f == 'function')					// function => our own function
+			return f.call(oDate, oDate, locale);
+		else if(f instanceof Array && typeof f[0] === 'string')		// built in function with padding
+			return xPad(oDate[f[0]](), f[1]);
+		else {
+			console.warn("unrecognised replacement type, please file a bug (format: " + sFormat + ")");
+			return m1;
+		}
+	};
+
+	// Preprocess by replacing %% with %<BS>, then later we'll replace %<BS> with %%
+	// XXX this is a hack.  There's a very low, but non-0 probability that an actual %<BS>
+	// will show up in a string, and this will break when that happens. -- Philip 2011/01/10
+	sFormat = sFormat.replace(/%%/g, "%\b");
+
+	// First replace aggregates (run in a loop because an agg may be made up of other aggs)
+	while(sFormat.match(/%[cDFhnrRtTxX]/)) {
+		sFormat = sFormat.replace(/%([cDFhnrRtTxX])/g, replace_aggs);
+	}
+
+	// Now replace formats (do not run in a loop otherwise %%a will be replaced with the value of %a)
+	var str = sFormat.replace(/%([aAbBCdegGHIjklmMpPsSuUVwWyYzZ])/g, replace_formats);
+
+	// Post-process now to change %<BS> back to %%
+	str = str.replace("%\b", '%%');
+
+	replace_aggs = replace_formats = undefined;
+
+	return str;
+}
+
+var LOCALES = {};
+
+LOCALES['en'] = {
+	a: ["Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat"],
+	A: ["Sunday", "Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday"],
+	b: ["Jan", "Feb", "Mar", "Apr", "May", "Jun", "Jul", "Aug", "Sep", "Oct", "Nov", "Dec"],
+	B: ["January", "February", "March", "April", "May", "June", "July", "August", "September", "October", "November", "December"],
+	c: "%a %d %b %Y %T %Z",
+	p: ["AM", "PM"],
+	P: ["am", "pm"],
+	r: "%I:%M:%S %p",
+	x: "%d/%m/%y",
+	X: "%T"
+};
+
+function addLocale(sName, oLocale, sBase) {
+	if(!sBase)
+		sBase = 'en';
+	LOCALES[sName] = oLocale;
+
+	for(k in LOCALES[sBase]) {
+		if(!(k in oLocale)) {
+			LOCALES[sName][k] = LOCALES[sBase][k];
+		}
+	}
+}
+
+addLocale('en-US', {
+	c: "%a %d %b %Y %I:%M:%S %p %Z",
+	x: "%m/%d/%Y",
+	X: "%I:%M:%S %p"
+});
+
+addLocale('en-GB', {
+	r: "%l:%M:%S %P %Z"
+});
+
+addLocale('en-AU', {});
+
+strftime.addLocale=addLocale;
+module.exports = strftime;
+