User:Ahecht/Scripts/UTCLiveClock.js

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/**
 * 
 * This gadget adds a clock in the personal toolbar that shows the current time
 * in UTC (or a different timezone of your choosing), and also provides a link
 * to recursively purge the current page.
 *
 * Based on: https://www.mediawiki.org/wiki/MediaWiki:Gadget-UTCLiveClock.js (Revision: July 2020)
 *
 * Installation:
 * 
 * Add the following line to [[Special:MyPage/common.js]] or [[:meta:Special:MyPage/global.js]] to install:
 *    mw.loader.load( "//en.wiki.x.io/w/index.php?title=User:Ahecht/Scripts/UTCLiveClock.js&action=raw&ctype=text/javascript" ); // Linkback: [[:en:User:Ahecht/Scripts/UTCLiveClock.js]]
 * 
 * To set the timezone used to one other than UTC, set window.LiveClockTimeZone to
 * the desired timezone. For example, adding the following to your common.js
 *      window.LiveClockTimeZone = 'America/Los_Angeles';
 * would result in the local time in Los Angeles being shown. See
 * [[:w:List of tz database time zones]] for valid options (use the TZ database name).
 * 
 **/
/* Below line defaults to a recursive link update */
window.LiveClockPurgeType = window.LiveClockPurgeType || "forcerecursivelinkupdate";

/*global mw, $ */
mw.loader.using( ['mediawiki.util', 'mediawiki.api', 'user'] ).then( function () {
var liveClockTimeZoneFormat, liveClockDateFormat;

function makeTzFunction() {
	window.LiveClockTimeZone_old = window.LiveClockTimeZone;
	var timezone = window.LiveClockTimeZone || 'UTC';
	if ( timezone == 'local' ) return false;
	try {
		return new Intl.DateTimeFormat('en-US', {
			timeZone: timezone,
			dateStyle:'medium',
			timeStyle:'medium'
		}).format;
	} catch ( err ) {
		console.warn( "LiveClock - error creating Intl object with timezone '" + timezone + "': " + err.name);
		if ( timezone == 'UTC' ) return false;
		window.LiveClockTimeZone = 'UTC';
		return makeTzFunction();
	}
}

function padWithZeroes( num ) {
	// Pad a number with zeroes. The number must be an integer where
	// 0 <= num < 100.
	return num < 10 ? '0' + num.toString() : num.toString(); 
}

function showTime( $target ) {
	var now = new Date();

	if ( window.LiveClockTimeZone_old != window.LiveClockTimeZone ) {
		liveClockTimeZoneFormat = makeTzFunction();
	}
	
	// Set the time.
	var newNow = now;
	if ( liveClockTimeZoneFormat !== false ) {
		newNow = new Date( liveClockTimeZoneFormat(now) );
	}
	var time = padWithZeroes( newNow.getHours() ) + ':' + padWithZeroes( newNow.getMinutes() );
	if ( !(window.LiveClockHideSeconds || false) ) {
		time = time + ':' + padWithZeroes( newNow.getSeconds() );
	}	
	$target.text( time );	
	
	// Set the date.
	$target.attr( 'title', liveClockDateFormat(newNow) );

	// Schedule the next time change.
	// 
	// We schedule the change for 100 ms _after_ the next clock tick. The delay
	// from setTimeout is not precise, and if we aim exactly for the tick, there
	// is a chance that the function will run slightly before it. If this
	// happens, we will display the same time for two seconds in a row - not
	// good. By scheduling 100 ms after the tick, we will always be about 100 ms
	// late, but we are also very likely to display a new time every second.
	var ms = now.getUTCMilliseconds();
	setTimeout( function () {
		showTime( $target );
	}, 1100 - ms );
}

function liveClock() {
	// Set CSS styles. We do this here instead of on the CSS page because some
	// wikis load this page directly, without loading the accompanying CSS.
	mw.util.addCSS( '#utcdate a { font-weight:bolder; font-size:120%; }' );

	// Reset whitespace that was set in the peer CSS gadget; this prevents the
	// effect of the p-personal menu jumping to the left when the JavaScript
	// loads.
	$( '.client-js > body.skin-vector #p-personal ul' ).css( 'margin-right', 'initial' );
	$( '.client-js > body.skin-monobook #p-personal ul' ).css( 'margin-right', 'initial' );
	
	// Create date/time formatting functions. This is done once as opposed to using
	// toLocaleString to avoid multiple localization database lookups.
	liveClockDateFormat = new Intl.DateTimeFormat( navigator.language, {dateStyle: 'full'} ).format;
	liveClockTimeZoneFormat = makeTzFunction();
	
	// We are experimenting with different locations for this in Vector 2022 based on feedback
	// so currently this is limited to MediaWiki.org
	var dbName = mw.config.get( 'wgDBname' );
	var showOutsideDropdown = dbName === 'mediawikiwiki' || dbName === 'enwiki';
	var clockLocation = document.getElementById( 'p-vector-user-menu-overflow' ) && showOutsideDropdown ?
		'p-vector-user-menu-overflow' : 'p-personal';
	addLiveClockInstance( clockLocation );
	addLiveClockInstance( 'p-personal-sticky-header' );
}

function addLiveClockInstance( clockLocation ) {
	var purge = { action: 'purge' };
	var re = new RegExp( '^force(?:recursive)?linkupdate$' );
	if ( re.test(window.LiveClockPurgeType) ) {
		purge[window.LiveClockPurgeType] = '1';
	}
	
	// Add the portlet link.
	var node = mw.util.addPortletLink(
		clockLocation,
		mw.util.getUrl( null, purge ),
		'',
		'utcdate',
		''
	);
	if ( !node ) {
		return;
	}

	// Purge the page when the clock is clicked. We have to do this through the
	// API, as purge URLs now make people click through a confirmation screen.
	$( node ).on( 'click', function ( e ) {
		purge.titles = mw.config.get( 'wgPageName' );
		new mw.Api().post( purge ).then( function () {
			location.reload();
		}, function () {
			mw.notify( 'Purge failed', { type: 'error' } );
		} );
		e.preventDefault();
	} );

	// Show the clock.
	showTime( $( node ).find( 'a' ).first() );
}

$( liveClock );
} );