mediawiki-skins-Vector/vector.js

/**
 * Vector-specific scripts
 */
/* eslint-disable no-jquery/no-global-selector */
$( function () {

	/**
	 * Collapsible tabs
	 */
	var $cactions = $( '#p-cactions' ),
		$tabContainer = $( '#p-views ul' ),
		// Avoid forced style calculation during page load
		initialCactionsWidth = function () {
			var width = $cactions.width();
			initialCactionsWidth = function () {
				return width;
			};
			return width;
		};

	mw.requestIdleCallback( initialCactionsWidth );

	// Bind callback functions to animate our drop down menu in and out
	// and then call the collapsibleTabs function on the menu
	$tabContainer
		.on( 'beforeTabCollapse', function () {
			// If the dropdown was hidden, show it
			if ( $cactions.hasClass( 'emptyPortlet' ) ) {
				$cactions.removeClass( 'emptyPortlet' );
				// eslint-disable-next-line no-jquery/no-animate
				$cactions.find( 'h3' )
					.css( 'width', '1px' )
					.animate( { width: initialCactionsWidth() }, 'normal' );
			}
		} )
		.on( 'beforeTabExpand', function () {
			// If we're removing the last child node right now, hide the dropdown
			if ( $cactions.find( 'li' ).length === 1 ) {
				// eslint-disable-next-line no-jquery/no-animate
				$cactions.find( 'h3' ).animate( { width: '1px' }, 'normal', function () {
					$( this ).attr( 'style', '' )
						.parent().addClass( 'emptyPortlet' );
				} );
			}
		} )
		.collapsibleTabs( {
			expandCondition: function ( eleWidth ) {
				// This looks a bit awkward because we're doing expensive queries as late
				// as possible.
				var distance = $.collapsibleTabs.calculateTabDistance();
				// If there are at least eleWidth + 1 pixels of free space, expand.
				// We add 1 because .width() will truncate fractional values but .offset() will not.
				if ( distance >= eleWidth + 1 ) {
					return true;
				} else {
					// Maybe we can still expand? Account for the width of the "Actions" dropdown
					// if the expansion would hide it.
					if ( $cactions.find( 'li' ).length === 1 ) {
						return distance >= eleWidth + 1 - initialCactionsWidth();
					} else {
						return false;
					}
				}
			},
			collapseCondition: function () {
				var collapsibleWidth = 0;

				// This looks a bit awkward because we're doing expensive queries as late
				// as possible.
				// TODO: The dropdown itself should probably "fold" to just the down-arrow
				// (hiding the text) if it can't fit on the line?

				// Never collapse if there is no overlap.
				if ( $.collapsibleTabs.calculateTabDistance() >= 0 ) {
					return false;
				}

				// Always collapse if the "More" button is already shown.
				if ( !$cactions.hasClass( 'emptyPortlet' ) ) {
					return true;
				}

				$tabContainer.children( 'li.collapsible' ).each( function ( index, element ) {
					collapsibleWidth += $( element ).width();
					// Stop this possibly expensive loop the moment the condition is met.
					return !( collapsibleWidth > initialCactionsWidth() );
				} );
				return collapsibleWidth > initialCactionsWidth();
			}
		} );
} );