Relative Time JS

relativeTime.js

/**
	 * Relative time converter
	 * FIXME: fix hardcoded strings (ago, just now)
	 * @param {Date} dateObj Date object to convert to string
	 * @return {String} 
	 */
	var relativeTime = function(dateObj) {
		var delta = new Date() - dateObj;
		now_threshold = 5000;
		if (delta <= now_threshold) {
			return 'just now';
		}
		var units = null, conversions = {
			millisecond: 1,
			second: 1000,
			minute: 60,
			hour: 60,
			day: 24,
			month: 30,
			year: 12
		};

		for (var key in conversions) {
			if (delta < conversions[key]) {
				break;
			} else {
				units = key;
				delta = delta / conversions[key];
			}
		}
		delta = Math.floor(delta);
		if (delta !== 1) { units += "s"; }
		return [delta, units, " ago "].join(" ");
	};