core/library/jquery.timeago.js

/**
 * Timeago is a jQuery plugin that makes it easy to support automatically
 * updating fuzzy timestamps (e.g. "4 minutes ago" or "about 1 day ago").
 *
 * @name timeago
 * @version 0.11.4
 * @requires jQuery v1.2.3+
 * @author Ryan McGeary
 * @license MIT License - http://www.opensource.org/licenses/mit-license.php
 *
 * For usage and examples, visit:
 * http://timeago.yarp.com/
 *
 * Copyright (c) 2008-2012, Ryan McGeary (ryan -[at]- mcgeary [*dot*] org)
 */
(function($) {
	$.timeago = function(timestamp) {
		if (timestamp instanceof Date) {
			return inWords(timestamp);
		} else if (typeof timestamp === "string") {
			return inWords($.timeago.parse(timestamp));
		} else if (typeof timestamp === "number") {
			return inWords(new Date(timestamp));
		} else {
			return inWords($.timeago.datetime(timestamp));
		}
	};
	var $t = $.timeago;

	$.extend($.timeago, {
			settings: {
				refreshMillis: 60000,
					allowFuture: false,
					strings: {
					prefixAgo: null,
						prefixFromNow: null,
						suffixAgo: "ago",
						suffixFromNow: "from now",
						seconds: "less than a minute",
						minute: "about a minute",
						minutes: "%d minutes",
						hour: "about an hour",
						hours: "about %d hours",
						day: "a day",
						days: "%d days",
						month: "about a month",
						months: "%d months",
						year: "about a year",
						years: "%d years",
						wordSeparator: " ",
						numbers: []
						}
			},
				inWords: function(distanceMillis) {
				var $l = this.settings.strings;
				var prefix = $l.prefixAgo;
				var suffix = $l.suffixAgo;
				if (this.settings.allowFuture) {
					if (distanceMillis < 0) {
						prefix = $l.prefixFromNow;
						suffix = $l.suffixFromNow;
					}
				}

				var seconds = Math.abs(distanceMillis) / 1000;
				var minutes = seconds / 60;
				var hours = minutes / 60;
				var days = hours / 24;
				var years = days / 365;

				function substitute(stringOrFunction, number) {
					var string = $.isFunction(stringOrFunction) ? stringOrFunction(number, distanceMillis) : stringOrFunction;
					var value = ($l.numbers && $l.numbers[number]) || number;
					return string.replace(/%d/i, value);
				}

				var words = seconds < 45 && substitute($l.seconds, Math.round(seconds)) ||
					seconds < 90 && substitute($l.minute, 1) ||
					minutes < 45 && substitute($l.minutes, Math.round(minutes)) ||
					minutes < 90 && substitute($l.hour, 1) ||
					hours < 24 && substitute($l.hours, Math.round(hours)) ||
					hours < 42 && substitute($l.day, 1) ||
					days < 30 && substitute($l.days, Math.round(days)) ||
					days < 45 && substitute($l.month, 1) ||
					days < 365 && substitute($l.months, Math.round(days / 30)) ||
					years < 1.5 && substitute($l.year, 1) ||
					substitute($l.years, Math.round(years));

				var separator = $l.wordSeparator === undefined ?  " " : $l.wordSeparator;
				return $.trim([prefix, words, suffix].join(separator));
			},
				parse: function(iso8601) {
				var s = $.trim(iso8601);
				s = s.replace(/\.\d+/,""); // remove milliseconds
				s = s.replace(/-/,"/").replace(/-/,"/");
				s = s.replace(/T/," ").replace(/Z/," UTC");
				s = s.replace(/([\+\-]\d\d)\:?(\d\d)/," $1$2"); // -04:00 -> -0400
				return new Date(s);
			},
				datetime: function(elem) {
				var iso8601 = $t.isTime(elem) ? $(elem).attr("datetime") : $(elem).attr("title");
				return $t.parse(iso8601);
			},
				isTime: function(elem) {
				// jQuery's `is()` doesn't play well with HTML5 in IE
				return $(elem).get(0).tagName.toLowerCase() === "time"; // $(elem).is("time");
			}
		});

	$.fn.timeago = function() {
		var self = this;
		self.each(refresh);

		var $s = $t.settings;
		if ($s.refreshMillis > 0) {
			setInterval(function() { self.each(refresh); }, $s.refreshMillis);
		}
		return self;
	};

	function refresh() {
		var data = prepareData(this);
		if (!isNaN(data.datetime)) {
			$(this).text(inWords(data.datetime));
		}
		return this;
	}

	function prepareData(element) {
		element = $(element);
		if (!element.data("timeago")) {
			element.data("timeago", { datetime: $t.datetime(element) });
			var text = $.trim(element.text());
			if (text.length > 0 && !($t.isTime(element) && element.attr("title"))) {
				element.attr("title", text);
			}
		}
		return element.data("timeago");
	}

	function inWords(date) {
		return $t.inWords(distance(date));
	}

	function distance(date) {
		return (new Date().getTime() - date.getTime());
	}

	// fix for IE6 suckage
	document.createElement("abbr");
	document.createElement("time");
}(jQuery));