MediaWiki:Gadget-challenge-live-tracker.js

( function ( $ ) {
	'use strict';
	
	$( function() {
		var $bubbles = $( '#cl-tracker' ).children();
		
		var today = new Date(
			new Date().toLocaleString( 'en-US', { timeZone: 'Asia/Tokyo' } )
		);
		var day = today.getDay();
		
		if ( today.getHours() < 4 ) { // go back a bubble if before 4 AM
			day = ( day - 1 + 7 ) % 7; // wrap between 0-6
		}
		
		if ( day === 0 ) { // 0 is sunday, which is day 7 in CL
			day = 7;
		}
		
		$bubbles.each( function( index ) {
			if ( index < day ) {
				$( this ).addClass( 'cl-bubble-complete' );
			}
		} );
	} );
	
} )( jQuery );