/*
 * JavaScript Pretty Date
 * Copyright (c) 2008 John Resig (jquery.com)
 * Licensed under the MIT license.
 */

// Takes an ISO time and returns a string representing how
// long ago the date represents.
function prettyDate(time){
	var date    = new Date();
	var current = Math.floor(date.getTime() / 1000);
	var comment = isoDateStringToDate(time);
	var publish = Math.floor(comment.getTime() / 1000);
	diff        = (current - publish);

	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" ||
		day_diff > 30 && 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 );
		});
	};

function isoDateStringToDate(datestr) {
  if (! this.re) {
    var datere = "(\\d{4})-?(\\d{2})-?(\\d{2})";
    var timere = "(\\d{2}):?(\\d{2}):?(\\d{2}(?:\\.\\d+)?)";
    var tzre = "(Z|(?:\\+|-)\\d{2}(?:\\:\\d{2})?)?";
    this.re = new RegExp("^" + datere + "[ T]" + timere + tzre + "$");
  }
  var matches = this.re.exec(datestr);
  if (! matches)
    return null;
  var year = matches[1];
  var month = matches[2] - 1;
  var day = matches[3];
  var hour = matches[4];
  var minute = matches[5];
  var second = Math.floor(matches[6]);
  var ms = matches[6] - second;
  var tz = matches[7];
  var ms = 0;
  var offset = 0;
  if (tz && tz != "Z") {
    var tzmatches = tz.match(/^(\+|-)(\d{2})(\:(\d{2}))$/);
    if (tzmatches) {
      offset = Number(tzmatches[2]) * 60 + Number(tzmatches[4]);
      if (tzmatches[1] == "-")
        offset = -offset;
    }
  }
  offset *= 60 * 1000;
  var dateval = Date.UTC(year, month, day, hour, minute, second, ms) - offset;
  return new Date(dateval);
}
