File: javascript/pretty_date.js

function prettyLinks(){
  var links = document.getElementsByTagName("a"); 
  for ( var i = 0; i < links.length; i++ )
    if ( links[i].title ) {
      var date = prettyDate(links[i].title);
      if ( date )
        links[i].innerHTML = date;
    }
}
prettyLinks();
setInterval(prettyLinks, 5000);


/*
 * JavaScript Pretty Date
 * Copyright (c) 2011 John Resig (ejohn.org)
 * Licensed under the MIT and GPL licenses.
 */

// Takes an ISO time and returns a string representing how
// long ago the date represents.
function prettyDate(time){
	var date = new Date((time || "").replace(/-/g,"/").replace(/[TZ]/g," ")),
		diff = (((new Date()).getTime() - date.getTime()) / 1000),
		day_diff = Math.floor(diff / 86400);
			
	if ( isNaN(day_diff) || day_diff < 0 || day_diff >= 31 )
		return;
			
	return day_diff == 0 && (
			diff < 60 && "just now" ||
			diff < 120 && "1 minute ago" ||
			diff < 3600 && Math.floor( diff / 60 ) + " minutes ago" ||
			diff < 7200 && "1 hour ago" ||
			diff < 86400 && Math.floor( diff / 3600 ) + " hours ago") ||
		day_diff == 1 && "Yesterday" ||
		day_diff < 7 && day_diff + " days ago" ||
		day_diff < 31 && Math.ceil( day_diff / 7 ) + " weeks ago";
}

// If jQuery is included in the page, adds a jQuery plugin to handle it as well
if ( typeof jQuery != "undefined" )
	jQuery.fn.prettyDate = function(){
		return this.each(function(){
			var date = prettyDate(this.title);
			if ( date )
				jQuery(this).text( date );
		});
	};

$("a").prettyDate();
setInterval(function(){ $("a").prettyDate(); }, 5000);






function pretty_date(date_str) {
    var time = ('' + date_str).replace(/-/g, "/").replace(/[TZ]/g, " ");
    var seconds = (new Date - new Date(time)) / 1000;
    var token = 'ago',
        list_choice = 1;
    if (seconds < 0) {
        seconds = Math.abs(seconds);
        token = 'from now';
        list_choice = 2;
    }
    var i = 0,
        format;
    while (format = time_formats[i++]) if (seconds < format[0]) {
        if (typeof format[2] == 'string') return format[list_choice];
        else return Math.floor(seconds / format[2]) + ' ' + format[1] + ' ' + token;
    }
    return time;
};
var time_formats = [
    [60, 'just now', 1], // 60   
    [120, '1 minute ago', '1 minute from now'], // 60*2   
    [3600, 'minutes', 60], // 60*60, 60   
    [7200, '1 hour ago', '1 hour from now'], // 60*60*2   
    [86400, 'hours', 3600], // 60*60*24, 60*60   
    [172800, 'yesterday', 'tomorrow'], // 60*60*24*2   
    [604800, 'days', 86400], // 60*60*24*7, 60*60*24   
    [1209600, 'last week', 'next week'], // 60*60*24*7*4*2   
    [2419200, 'weeks', 604800], // 60*60*24*7*4, 60*60*24*7   
    [4838400, 'last month', 'next month'], // 60*60*24*7*4*2   
    [29030400, 'months', 2419200], // 60*60*24*7*4*12, 60*60*24*7*4   
    [58060800, 'last year', 'next year'], // 60*60*24*7*4*12*2   
    [2903040000, 'years', 29030400], // 60*60*24*7*4*12*100, 60*60*24*7*4*12   
    [5806080000, 'last century', 'next century'], // 60*60*24*7*4*12*100*2   
    [58060800000, 'centuries', 2903040000] // 60*60*24*7*4*12*100*20, 60*60*24*7*4*12*100 
    ];


/*
 * Javascript Humane Dates
 * Copyright (c) 2008 Dean Landolt (deanlandolt.com)
 * Re-write by Zach Leatherman (zachleat.com)
 * 
 * Adopted from the John Resig's pretty.js
 * at http://ejohn.org/blog/javascript-pretty-date
 * and henrah's proposed modification 
 * at http://ejohn.org/blog/javascript-pretty-date/#comment-297458
 * 
 * Licensed under the MIT license.
 */

function humane_date(date_str){
	var time_formats = [
		[60, 'Just Now'],
		[90, '1 Minute'], // 60*1.5
		[3600, 'Minutes', 60], // 60*60, 60
		[5400, '1 Hour'], // 60*60*1.5
		[86400, 'Hours', 3600], // 60*60*24, 60*60
		[129600, '1 Day'], // 60*60*24*1.5
		[604800, 'Days', 86400], // 60*60*24*7, 60*60*24
		[907200, '1 Week'], // 60*60*24*7*1.5
		[2628000, 'Weeks', 604800], // 60*60*24*(365/12), 60*60*24*7
		[3942000, '1 Month'], // 60*60*24*(365/12)*1.5
		[31536000, 'Months', 2628000], // 60*60*24*365, 60*60*24*(365/12)
		[47304000, '1 Year'], // 60*60*24*365*1.5
		[3153600000, 'Years', 31536000], // 60*60*24*365*100, 60*60*24*365
		[4730400000, '1 Century'], // 60*60*24*365*100*1.5
	];

	var time = ('' + date_str).replace(/-/g,"/").replace(/[TZ]/g," "),
		dt = new Date,
		seconds = ((dt - new Date(time) + (dt.getTimezoneOffset() * 60000)) / 1000),
		token = ' Ago',
		i = 0,
		format;

	if (seconds < 0) {
		seconds = Math.abs(seconds);
		token = '';
	}

	while (format = time_formats[i++]) {
		if (seconds < format[0]) {
			if (format.length == 2) {
				return format[1] + (i > 1 ? token : ''); // Conditional so we don't return Just Now Ago
			} else {
				return Math.round(seconds / format[2]) + ' ' + format[1] + (i > 1 ? token : '');
			}
		}
	}

	// overflow for centuries
	if(seconds > 4730400000)
		return Math.round(seconds / 4730400000) + ' Centuries' + token;

	return date_str;
};

if(typeof jQuery != 'undefined') {
	jQuery.fn.humane_dates = function(){
		return this.each(function(){
			var date = humane_date(this.title);
			if(date && jQuery(this).text() != date) // don't modify the dom if we don't have to
				jQuery(this).text(date);
		});
	};
}