source: Dev/trunk/src/client/dojox/date/relative.js

define(["..", "dojo/_base/lang", "dojo/date/locale", "dojo/i18n"], function(dojox, lang, ddl, i18n){

var drelative = lang.getObject("date.relative", true, dojox);

/*=====
var __FormatOptions = {
        // locale: String
        //              override the locale used to determine formatting rules
        // relativeDate: Date
        //              Date to calculate relation to (defaults to new Date())
        // weekCheck: boolean
        //              Whether or not to display the day of week (defaults true)
};
=====*/

var DAY = 1000*60*60*24,
        SIX_DAYS = 6 * DAY,
        del = dojo.delegate,
        ggb = ddl._getGregorianBundle,
        fmt = ddl.format;

function _clearTime(date){
        date = new Date(date);
        date.setHours(0, 0, 0, 0);
        return date;
}

drelative.format = function(/*Date*/dateObject, /*__FormatOptions?*/options){
        // summary:
        //              Format a Date object as a String, using locale-specific settings,
        //              relative to the current date or some other date.
        //
        // description:
        //              Create a string from a Date object using the most significant information
        //              and a known localized pattern.  This method formats both the date and
        //              time from dateObject.  Formatting patterns are chosen appropriate to
        //              the locale.
        //
        //              If the day portion of the date falls within the current date (or the
        //              relativeDate option, if present), then the time will be all that
        //              is displayed
        //
        //              If the day portion of the date falls within the past week (or the
        //              week preceeding relativeDate, if present), then the display will show
        //              day of week and time.  This functionality can be turned off by setting
        //              weekCheck to false.
        //
        //              If the year portion of the date falls within the current year (or the
        //              year portion of relativeDate, if present), then the display will show
        //              month and day.
        //
        //              Otherwise, this function is equivalent to calling dojo.date.format with
        //              formatLength of "medium"
        //
        // dateObject:
        //              the date and time to be formatted.
        
        options = options || {};
        
        var today = _clearTime(options.relativeDate || new Date()),
                diff = today.getTime() - _clearTime(dateObject).getTime(),
                fmtOpts = {locale: options.locale};
        
        if(diff === 0){
                // today: 9:32 AM
                return fmt(dateObject, del(fmtOpts, {selector: "time"}));
        }else if(diff <= SIX_DAYS && diff > 0 && options.weekCheck !== false){
                // within the last week: Mon 9:32 am
                return fmt(dateObject, del(fmtOpts, {selector: "date", datePattern: "EEE"})) +
                                " " +
                                fmt(dateObject, del(fmtOpts, {selector: "time", formatLength: "short"}));
        }else if(dateObject.getFullYear() == today.getFullYear()){
                // this year: Nov 1
                var bundle = ggb(i18n.normalizeLocale(options.locale));
                return fmt(dateObject, del(fmtOpts, {
                        selector: "date",
                        datePattern: bundle["dateFormatItem-MMMd"]
                }));
        }else{
                // default: Jun 1, 2010
                return fmt(dateObject, del(fmtOpts, {
                        selector: "date",
                        formatLength: "medium",
                        locale: options.locale
                }));
        }
};

        return drelative;
});