MediaWiki:Gadget-countdown.js

(function ($) {
	function format(n, suffixes) {
		var pr = new Intl.PluralRules('en-US');
		return n + ' ' + suffixes[pr.select(n)];
	}
	
	function calcDiff(d1, d2) {
		var remDiff = d2 - d1;
		var days = Math.floor(remDiff / (1000*60*60*24));
		remDiff = remDiff % (1000*60*60*24);
		var hours = Math.floor(remDiff / (1000*60*60));
		remDiff = remDiff % (1000*60*60);
		var minutes = Math.floor(remDiff / (1000*60));
		
		return {
			days: days,
			hours: hours,
			minutes: minutes
		};
	}
	
	var daySuffixes = {
		one: 'day',
		other: 'days',
	};
	var hourSuffixes = {
		one: 'hour',
		other: 'hours'
	};
	var minuteSuffixes = {
		one: 'minute',
		other: 'minutes'
	};
	
	function updateHTML(targetDate, countdownNode, finishedText) {
		var finished = false;
		var diff = calcDiff(new Date(), targetDate);
		
		countdownNode.html(
			format(diff.days, daySuffixes) + 
			', ' +
			format(diff.hours, hourSuffixes) +
			', ' +
			format(diff.minutes, minuteSuffixes)
		);
		
		if (diff.days <= 0 && diff.hours <= 0 && diff.minutes <= 0) {
			countdownNode.html(finishedText || 'Countdown has ended');
			finished = true;
		}
		
		return finished;
	}
	
	function init() {
		$('.js-countdown-wrapper').each(function(idx) {
			
			var countdown = $(this).children('.js-countdown');
			var d1 = new Date(countdown.data('countdown-end'));
			
			updateHTML(d1, countdown, countdown.data('end-text'));
			
			var interval = setInterval(function() {
				var finished = updateHTML(d1, countdown, countdown.data('end-text'));
				if (finished) {
					clearInterval(interval);
				}
			}, 30000);
		});
	}
	
	$(document).ready(init);
})(jQuery);