wikimedia/mediawiki-extensions-UniversalLanguageSelector

/*!
 * ULS-Webfonts integration
 *
 * Copyright (C) 2012 Alolita Sharma, Amir Aharoni, Arun Ganesh, Brandon Harris,
 * Niklas Laxström, Pau Giner, Santhosh Thottingal, Siebrand Mazeland and other
 * contributors. See CREDITS for a list.
 *
 * UniversalLanguageSelector is dual licensed GPLv2 or later and MIT. You don't
 * have to do anything special to choose one license or the other and you don't
 * have to notify anyone which license you are using. You are free to use
 * UniversalLanguageSelector in commercial projects as long as the copyright
 * header is left intact. See files GPL-LICENSE and MIT-LICENSE for details.
 *
 * @file
 * @ingroup Extensions
 * @licence GNU General Public Licence 2.0 or later
 * @licence MIT License
 */

( function () {
    'use strict';

    var getULSPreferences = require( 'ext.uls.preferences' ),
        ulsPreferences = getULSPreferences();

    mw.webfonts = mw.webfonts || {};
    mw.webfonts.preferences = {
        registry: {
            fonts: {},
            webfontsEnabled: mw.config.get( 'wgULSWebfontsEnabled' )
        },

        isEnabled: function () {
            return this.registry.webfontsEnabled;
        },

        enable: function () {
            this.registry.webfontsEnabled = true;
        },

        disable: function () {
            this.registry.webfontsEnabled = false;
        },

        setFont: function ( language, font ) {
            this.registry.fonts[ language ] = font;
        },

        getFont: function ( language ) {
            return this.registry.fonts[ language ];
        },

        save: function ( callback ) {
            // get updated copy of preferences
            ulsPreferences = getULSPreferences();
            ulsPreferences.set( 'webfonts', this.registry );
            ulsPreferences.save( callback );
        },

        load: function () {
            mw.webfonts.preferences.registry = $.extend( this.registry,
                ulsPreferences.get( 'webfonts' ) );
        }
    };

    mw.webfonts.setup = function () {
        // Initialize webfonts
        var mediawikiFontRepository = $.webfonts.repository;

        mediawikiFontRepository.base = mw.config.get( 'wgULSFontRepositoryBasePath' );

        // MediaWiki specific overrides for jquery.webfonts
        $.extend( $.fn.webfonts.defaults, {
            repository: mediawikiFontRepository,
            fontStack: $( document.body ).css( 'font-family' ).split( /, /g ),
            /**
             * Returns a suitable font from font repository based
             * on the given language and html classes and user preference.
             *
             * @param {Object} repository
             * @param {string} language
             * @param {string[]} classes
             * @return {string|null}
             */
            fontSelector: function ( repository, language, classes ) {
                var font, defaultFont;

                if ( !language ) {
                    return null;
                }

                defaultFont = repository.defaultFont( language );

                if ( classes && classes.indexOf( 'autonym' ) >= 0 ) {
                    // Do not load font for showing autonym.
                    return null;
                }

                // If the user has a font preference, apply it always.
                font = mw.webfonts.preferences.getFont( language ) || defaultFont;
                if ( !font || font === 'system' ) {
                    // Avoid setting 'system' as a font in css
                    return null;
                }

                return font;
            },

            exclude: ( function () {
                var excludes = mw.config.get( 'wgULSNoWebfontsSelectors' ).join( ', ' );

                if ( mw.user.options.get( 'editfont' ) !== 'default' ) {
                    // Exclude textboxes from webfonts if the user has edit area font option
                    // set using 'Preferences' page
                    excludes = excludes ? excludes + ',textarea' : 'textarea';
                }

                return excludes;
            }() ),
            overridableFontFamilies: ( function () {
                var headingFont = $( 'h1' ).css( 'font-family' );
                return headingFont ? [ headingFont ] : [];
            }() )
        } );

        // Execute after task queue is processed so that the rendering is complete.
        // This is important because webfonts behavior depends on the font-family
        // property values set by stylesheets.
        setTimeout( function () {
            $( document.body ).webfonts();
        }, 0 );
    };

    $( function () {
        mw.webfonts.preferences.load();

        if ( mw.webfonts.preferences.isEnabled() ) {
            // Queue to next idle period to optimize loading.
            mw.requestIdleCallback( function () {
                mw.loader.using( 'ext.uls.webfonts.repository' ).then( mw.webfonts.setup );
            } );
        }
    } );

}() );