/*
 * timeago: a jQuery plugin, version: 0.8.2 (2010-02-16)
 * @requires jQuery v1.2.3 or later
 *
 * 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").
 *
 * For usage and examples, visit:
 * http://timeago.yarp.com/
 *
 * Licensed under the MIT:
 * http://www.opensource.org/licenses/mit-license.php
 *
 * Copyright (c) 2008-2010, Ryan McGeary (ryanonjavascript -[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 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",
				ago: null, // DEPRECATED, use suffixAgo
				fromNow: null, // DEPRECATED, use suffixFromNow
				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"
			}
		},
		inWords: function(distanceMillis) {
			var $l = this.settings.strings;
			var prefix = $l.prefixAgo;
			var suffix = $l.suffixAgo || $l.ago;
			if (this.settings.allowFuture) {
				if (distanceMillis < 0) {
					prefix = $l.prefixFromNow;
					suffix = $l.suffixFromNow || $l.fromNow;
				}
				distanceMillis = Math.abs(distanceMillis);
			}

			var seconds = distanceMillis / 1000;
			var minutes = seconds / 60;
			var hours = minutes / 60;
			var days = hours / 24;
			var years = days / 365;

			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($l.hours, Math.round(hours)) ||
				hours < 48 && substitute($l.day, 1) ||
				days < 30 && substitute($l.days, Math.floor(days)) ||
				days < 60 && substitute($l.month, 1) ||
				days < 365 && substitute($l.months, Math.floor(days / 30)) ||
				years < 2 && substitute($l.year, 1) ||
				substitute($l.years, Math.floor(years));

			return $.trim([prefix, words, suffix].join(" "));
		},
		parse: function(iso8601) {
			var s = $.trim(iso8601);
			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) {
			// jQuery's `is()` doesn't play well with HTML5 in IE
			var isTime = $(elem).get(0).tagName.toLowerCase() == "time"; // $(elem).is("time");
			var iso8601 = isTime ? $(elem).attr("datetime") : $(elem).attr("title");
			return $t.parse(iso8601);
		}
	});

	$.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) 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());
	}

	function substitute(stringOrFunction, value) {
		var string = $.isFunction(stringOrFunction) ? stringOrFunction(value) : stringOrFunction;
		return string.replace(/%d/i, value);
	}

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