kiwix-js-pwa/www/js/lib/transformStyles.js

/**
 * transformStyles.js: Provides transformations in CSS of Wikipedia articles contained in the ZIM file
 * This allows the user to choose the presentation style for the page to be viewed.
 * Currently available are "mobile" and "desktop" display modes.
 *
 * Copyright 2017 Kiwix developers
 * License GPL v3:
 *
 * This file is part of Kiwix.
 *
 * Kiwix is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * Kiwix is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with Kiwix (file LICENSE-GPLv3.txt).  If not, see <http://www.gnu.org/licenses/>
 */
/**
 * transformStyles.js: Provides transformations in CSS of Wikipedia articles contained in the ZIM file
 * This allows the user to choose the presentation style for the page to be viewed.
 * Currently available are "mobile" and "desktop" display modes.
 *
 * Copyright 2017 Kiwix developers
 * License GPL v3:
 *
 * This file is part of Kiwix.
 *
 * Kiwix is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * Kiwix is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with Kiwix (file LICENSE-GPLv3.txt).  If not, see <http://www.gnu.org/licenses/>
 */
'use strict';

import util from './util.js';

/* global params */

var prefix = (window.location.protocol + '//' + window.location.host + window.location.pathname).replace(/\/[^/]*$/, '/');
/* zl = zimLink; zim = zimType; cc = cssCache; cs = cssSource; i]  */
function filterCSS (zl, zim, cc, cs, i) {
    var rtnFunction = 'injectCSS';
    if ((zim !== cs) && zl.match(/(-\/(?:s\/css_modules\/|mw\/)?style\.css)|minerva|mobile|parsoid/i)) { // If it's the wrong ZIM type and style matches main styles...
        if (zl.match(/-\/(?:s\/|mw\/)?style\.css|minerva|style-mobile\.css/i)) { // If it matches one of the required styles...
            zl = (cs === 'mobile') ? prefix + '-/s/style-mobile.css' : prefix + '-/s/style.css'; // Take it from cache, because not in the ZIM
            console.log('Matched #' + i + ' [' + zl + '] from local filesystem because style is not in ZIM' +
                '\nbut your display options require a ' + cs + ' style');
        }
        if (cs === 'desktop' && /minerva|mobile|parsoid|(css_modules|mw)\/style\.css/.test(zl) && !/(css_modules|mw)\/mobile_main_page\.css/.test(zl)) {
            // If user selected desktop style and style is one of the mobile styles, but not mobile_main_page for newstyle all image homepages
            console.log('Voiding #' + i + ' [' + zl + '] from document header \nbecause your display options require a desktop style');
            zl = '#'; // Void these mobile styles
        }
        // Rename this required mobile style so that we don't trigger reading ZIM as mobile in print intercept
        zl = /(css_modules|mw)\/mobile_main_page\.css/.test(zl) && cs === 'desktop' ? prefix + '-/s/css_modules/newstyle_main_page.css' : zl;
    } else {
        // If this is a standard Wikipedia css use stylesheet cached in the filesystem...
        // DEV: Although "." matches any character in regex, there is enough specificity in the patterns below
        // DEV: Add any local stylesheets you wish to include here
        if (cc &&
            (/-\/(?:s\/|s\/css_modules\/|mw\/)?style.css/i.test(zl) ||
                /\/mediawiki.toc.css/i.test(zl) ||
                /\/ext.cite.styles.css/i.test(zl) ||
                /\/ext.timeline.styles.css/i.test(zl) ||
                /\/ext.scribunto.logs.css/i.test(zl) ||
                /\/mediawiki.page.gallery.styles.css/i.test(zl) ||
                /\/ext.cite.a11y.css/i.test(zl) ||
                /\/ext.kartographer.style.css/i.test(zl) ||
                /\/ext.kartographer.link.css/i.test(zl) ||
                /\/ext.kartographer.frame.css/i.test(zl) ||
                /\/mw.TMHGalleryHook.js.css/i.test(zl) ||
                /\/mw.PopUpMediaTransform.css/i.test(zl) ||
                /\/mw.MediaWikiPlayer.loader.css/i.test(zl) ||
                /\/ext.tmh.thumbnail.styles.css/i.test(zl) ||
                /\/ext.math.styles.css/i.test(zl) ||
                /\/ext.math.scripts.css/i.test(zl) ||
                /\/ext.inputBox.styles.css/i.test(zl) ||
                /\/ext.cite.ux-enhancements.css/i.test(zl) ||
                /\/mobile_main_page.css/i.test(zl) ||
                /\/mediawiki.ui.input.css/i.test(zl) ||
                /\/mediawiki.ui.checkbox.css/i.test(zl) ||
                /\/content.parsoid.css/i.test(zl) ||
                /\/inserted_style_mobile.css/i.test(zl) ||
                /\/inserted_style.css/i.test(zl) ||
                /\/meta.wikimedia.org\/api\/rest_v1\/data\/css\/mobile\/base.css/i.test(zl) ||
                /-\/static\/bootstrap\/css\/bootstrap.min.css/i.test(zl) ||
                /-\/static\/bootstrap\/css\/bootstrap-theme.min.css/i.test(zl) ||
                /-\/static\/main.css/i.test(zl) ||
                /\/static\/css\/sotoki.css/i.test(zl) ||
                /\/mobile.css/i.test(zl) ||
                /\/style-mobile.css/i.test(zl) ||
                /\/skins.minerva.base.reset\|skins.minerva.content.styles\|ext.cite.style\|mediawiki.page.gallery.styles\|mobile.app.pagestyles.android\|mediawiki.skinning.content.parsoid.css/i.test(zl)
            )) {
            zl = zl.replace(/\|/ig, '_'); // Replace "|" with "_" (legacy for some stylesheets with pipes in filename - but next line renders this redundant in current implementation)
            if (/(-\/(?:s\/css_modules\/|mw\/)?style\.css)|minerva|inserted_style_mobile|base\.css/i.test(zl)) { // If it matches one of the required styles...
                zl = cs === 'mobile' ? '-/s/style-mobile.css' : '-/s/style.css';
            }
            // Rename this required mobile style so that we don't trigger reading ZIM as mobile in print intercept
            zl = /\/mobile_main_page\.css/.test(zl) ? '-/mw/newstyle_main_page.css' : zl;
            zl = /\/content\.parsoid\.css/.test(zl) ? '-/s/css_modules/content.parsoid.css' : zl;
            zl = /\/sotoki\.css/.test(zl) ? 'C/static/css/sotoki.css' : zl;
            // Replace bootstrap with own: DEV: when upgrading to Bootstrap 4, stop doing this!
            zl = zl.replace(/.+(bootstrap[^/]*?\.css)/i, 'css/$1');
            console.debug('Matched #' + i + ' [' + zl + '] from local filesystem');
            // Make link absolute
            zl = zl.replace(/^[/.]*/, prefix);
            // injectCSS();
        } else if (params.contentInjectionMode === 'jquery') { // Try to get the stylesheet from the ZIM file unless it's the wrong ZIM type
            zl = zl.replace(/^[./]+/, ''); // Remove the directory path
            console.debug('Attempting to resolve CSS link #' + i + ' [' + zl + '] from ZIM file...' +
                (cc ? '\n(Consider adding file #' + i + ' to the local filesystem)' : ''));
            rtnFunction = 'resolveCSS';
        }
    }
    return { zl: zl, rtnFunction: rtnFunction };
}

function toMobileCSS (html, zim, cc, cs, css) {
    // DEV: Careful not to add styles twice...
    // NB Can't relocate to filterCSS function above because it filters styles serially and code would be called for every style...
    if (zim === 'desktop' && zim !== cs) { // If ZIM doesn't match user-requested style, add in stylesheets if they're missing
        css += /\/content\.parsoid\.css/i.test(css) ? '' : '<link href="' + prefix + '-/s/css_modules/content.parsoid.css" rel="stylesheet" type="text/css">\r\n';
        css += /\/inserted_style_mobile\.css/i.test(css) ? '' : '<link href="' + prefix + '-/s/style-mobile.css" rel="stylesheet" type="text/css">\r\n';
        css += /\/mobile\.css/i.test(css) ? '' : '<link href="' + prefix + '-/s/css_modules/mobile.css" rel="stylesheet" type="text/css">\r\n';
    }
    if (cc || (zim === 'desktop')) { // If user requested cached styles OR the ZIM does not contain mobile styles
        console.log(zim === 'desktop' ? 'Transforming display style to mobile...' : 'Optimizing cached styles for mobile display...');
        // Add styling to image captions that is hard-coded in Wikipedia mobile
        html = html.replace(/class\s*=\s*["']\s*thumbcaption\s*["']\s*/ig, 'style="margin: 0.5em 0 0.5em; font-size: 0.8em; line-height: 1.5; padding: 0 !important; color: #54595d; width: auto !important;"');
        // Wrap <h2> tags in <div> to control bottom border width if there's an infobox, but not if it's a new-style ZIM with collapsible details tags
        if (!/<details[\s\S]+?<summary\b/i.test(html)) {
            html = /<table\s+(?=[^>]*class\s*=\s*["'][^"']*(?:mw-stack|infobox|vertical-navbox|qbRight|wv-quickbar))/i.test(html) ? html.replace(/(<h2\s+[^<]*<\/h2>)/ig, '<div style="width: 60%;">$1</div>') : html;
        }
        if (zim === 'desktop') {
            var infobox = [];
            if (/<table\b[^>]+(?:mw-stack|infobox|vertical-navbox|qbRight|wv-quickbar)/i.test(html)) {
                infobox = util.matchOuter(html, '<table\\b[^>]+(?:mw-stack|infobox|vertical-navbox|qbRight|wv-quickbar)[^>]+>', '</table>', 'i');
            } else {
                if (/<div\b[^>]+(?:infobox|vertical-navbox|qbRight|wv-quickbar)/i.test(html)) {
                    infobox = util.matchOuter(html, '<div\\b[^>]+(?:infobox|vertical-navbox|qbRight|wv-quickbar)[^>]+>', '</div>', 'i');
                }
            }
            if (infobox.length) {
                var temphtml = html.replace(infobox[0], '<!-- @@@kiwixmarker@@@ -->');
                var paras = util.matchInner(temphtml, '<p\\b[^>]*>', '</p>', 'gi');
                var matched = false;
                if (paras.length) {
                    for (var g = 0; g < 3; g++) {
                        // Check if the paragraph is a proper sentence, i.e. contains at least 50 non-HTML-delimetered non-full-stop characters, followed by a punctuation character
                        if (paras[g] && /[^.]{50,}[^.]*[.,;:?!-]/.test(paras[g].replace(/<[^>]*>/g, ''))) { matched = true; break; }
                    }
                    if (matched) {
                        // If there are navboxes below the infobox, hide them in mobile view
                        temphtml = temphtml.replace(/(<div\b(?=[^>]+navbox))(?:([^>]+?)style\s*=\s*["']([^"']+)["'])?/ig, '$1$2style="display:none;$3"');
                        // Ensure mobile styling in infobox
                        infobox[0] = infobox[0].replace(/(<(?:table|div)\b(?=[^>]+?class\s*=\s*["'][^"']*(?:mw-stack|infobox|navbox)))([^>]+?style\s*=\s*["'])(?:([^"']*?)margin\s*:[^;"']*[;"'])?/ig, '$1$2margin:0 auto;$3');
                        // Clear any fixed width but set it to max-width
                        infobox[0] = infobox[0].replace(/^(<(?:table|div)\b[^>]+?;\s*width\s*:\s*)([^;"']+)/i, '$1auto;max-width:$2');
                        // Hide any navboxes inside the infobox
                        infobox[0] = infobox[0].replace(/(<(?:table|div)\b(?=[^>]+?class\s*=\s*["'][^"']*navbox))(?:([^>]+?)style\s*=\s*["'])(?:([^"']*?)display\s*:[^;"']*[;"'])?/ig, '$1$2style="display:none;$3');
                        // We already deleted the table above
                        html = '';
                        // First try to move the lead paragraph
                        html = temphtml.replace(/(<div\s+[^>]*?\bid\s*=\s*["']mw-content-text\s*[^>]*>\s*)/i, '$1\r\n' + paras[g].replace(/(<p\s+)/i, '$1data-kiwix-id="lead" ') + '\r\n');
                        if (html) { // Looks like we succeeded so clean up
                            html = html.replace(paras[g], '');
                            html = html.replace('<!-- @@@kiwixmarker@@@ -->', infobox[0]);
                        } else {
                            // So there was no match, let's try just swapping para and infobox
                            html = temphtml.replace(paras[g], paras[g].replace(/(<p\s+)/i, '$1data-kiwix-id="lead" ') + '\r\n' + infobox[0]);
                            html = html.replace('<!-- @@@kiwixmarker@@@ -->', '');
                        }
                    }
                }
            }
        }
        // Set infobox styling hard-coded in Wikipedia mobile
        html = html.replace(/(table\s+(?=[^>]*class\s*=\s*["'][^"']*(?:mw-stack|infobox|vertical-navbox|qbRight|wv-quickbar))[^>]*style\s*=\s*["'][^"']+[^;'"]);?\s*["']/ig, '$1; position: relative; border: 1px solid #eaecf0; text-align: left; background-color: #f8f9fa;"');
    }
    // Remove hard-coded style on h1
    html = html.replace(/(<h1\b[^>]+)background-color\s*:\s*white;\s*/i, '$1');

    return { html: html, css: css };
}

function toDesktopCSS (html, zim, cc, cs, css) {
    if (cc || (zim !== cs)) {
        if (/class\s*=\s*["']gallery/i.test(html) && !/gallery/i.test(css)) {
            console.log('Inserting missing css required for gallery display [mediawiki.page.gallery.styles.css]...');
            css += /\/mediawiki\.page\.gallery\.styles\.css/i.test(css) ? '' : '<link href="' + prefix + '-/s/css_modules/mediawiki.page.gallery.styles.css" rel="stylesheet" type="text/css">\r\n';
        }
    }
    if (cc || (zim === 'mobile')) { // If user requested cached styles OR the ZIM does not contain desktop styles
        console.log(zim === 'mobile' ? 'Transforming display style to desktop...' : 'Optimizing cached styles for desktop display...');
        // If it's in mobile position, move info-box above lead paragraph like on Wikipedia desktop
        if (zim === 'mobile') {
            // Attempt to match div-style infobox first
            var tableBox = util.matchOuter(html, '<div\\b[^>]+?(?:infobox[^-]|vertical-navbox|qbRight|wv-quickbar)[^>]*>', '</div>', 'i');
            // If above failed we may have traditional table-style infobox
            tableBox = !(tableBox && tableBox.length) ? util.matchOuter(html, '<table\\b[^>]+?(?:mw-stack|infobox[^-]|vertical-navbox|qbRight|wv-quickbar)[^>]*>', '</table>', 'i') : tableBox;
            if (tableBox && tableBox.length) {
                html = html.replace(tableBox, '');
                html = html.replace(/(<\/h1>\s*)/i, '$1' + tableBox);
            }
        }
        // Ensure white background colour
        html = html.replace(/(class\s*=\s*["']\s*mw-body\s*["'][^>]*?style\s*=\s*["'])/i, '$1background-color:white;');
        // Void empty header title
        html = html.replace(/<h1\s*[^>]+titleHeading[^>]+>\s*<\/h1>\s*/ig, '');
    }
    // Remove hard-coded style on h1
    html = html.replace(/(<h1\b[^>]+)background-color\s*:\s*white;\s*/i, '$1');
    // Remove hard-coded style on infobox
    html = html.replace(/(<table\s+(?=[^>]*?\bclass=['"][^'"]*infobox)[^>]*\bstyle=['"][^'"]*\b)(?:float:\s*none\s*;?\s*)(?:clear:\s*none\s*;?\s*)?/gi, '$1');
    // Remove any residual references to mobile styles (e.g. in data-kiwixhref) because they trigger page reload when printing
    css = css.replace(/(<link\b[^>]+)(minerva|mobile)/ig, '$1');
    return { html: html, css: css };
}

export default {
    toMobileCSS: toMobileCSS,
    toDesktopCSS: toDesktopCSS,
    filterCSS: filterCSS
};