/*
 * timeago: a jQuery plugin, version: 0.9.3 (2011-01-21)
 * @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) 2008-2011, Ryan McGeary (ryanonjavascript -[at]- mcgeary [*dot*] org)
 */
(function($) {
    $.timeago = function(timestamp) {
        if (timestamp instanceof Date) {
            return inWords(timestamp);
        } else if (typeof timestamp === "string") {
            var words = inWords($.timeago.parse(timestamp));
            if (words.search("NaN") > -1) {
                var r = /^[A-Za-z]+, (\d+) ([A-Za-z]+) (\d+) (\d+):(\d+):(\d+).*$/g;
                var m = r.exec(timestamp);
                var day = m[1];
                var month = m[2];
                if (month == "Jan")
                    month = 01;
                else if (month == "Feb")
                    month = 02;
                else if (month == "Mar")
                    month = 03;
                else if (month == "Apr")
                    month = 04;
                else if (month == "May")
                    month = 05;
                else if (month == "Jun")
                    month = 06;
                else if (month == "Jul")
                    month = 07;
                else if (month == "Aug")
                    month = 08;
                else if (month == "Sep")
                    month = 09;
                else if (month == "Oct")
                    month = 10;
                else if (month == "Nov")
                    month = 11;
                else if (month == "Dec")
                    month = 12;
                var year = m[3];
                var hour = m[4];
                var minute = m[5];
                var second = m[6];
                timestamp = year + "-" + month + "-" + day + "Z" + hour + ":" + minute + ":" + second;
                words = inWords($.timeago.parse(timestamp));
            }

            return words;
        } 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",
                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;
                }
                distanceMillis = Math.abs(distanceMillis);
            }

            var seconds = 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($l.hours, Math.round(hours)) ||
            hours < 48 && substitute($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(/\.\d\d\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) {
            // 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());
    }

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