User:Polygnotus/Scripts/Subpages.js

Code that you insert on this page could contain malicious content capable of compromising your account. If you import a script from another page with "importScript", "mw.loader.load", "iusc", or "lusc", take note that this causes you to dynamically load a remote script, which could be changed by others. Editors are responsible for all edits and actions they perform, including by scripts. User scripts are not centrally supported and may malfunction or become inoperable due to software changes. A guide to help you find broken scripts is available. If you are unsure whether code you are adding to this page is safe, you can ask at the appropriate village pump.
This code will be executed when previewing this page.

Documentation for this user script can be added at User:Polygnotus/Scripts/Subpages.

Note: After saving, you have to bypass your browser's cache to see the changes. Google Chrome, Firefox, Microsoft Edge and Safari: Hold down the ⇧ Shift key and click the Reload toolbar button. For details and instructions about other browsers, see Wikipedia:Bypass your cache.

// <nowiki>
// Add subpage navigation below page title
(function() {
    'use strict';
    
    // Only run on article view (not edit, preview, etc.)
    var action = mw.config.get('wgAction');
    if (action !== 'view') {
        return;
    }
    
    var pageName = mw.config.get('wgPageName');
    var pageTitle = mw.config.get('wgTitle');
    var namespace = mw.config.get('wgNamespaceNumber');
    
    // Guard against Special pages (ns -1) and Media pages (ns -2)
    if (namespace < 0) {
        return;
    }
    
    var searchPrefix = pageTitle + '/';
    var api = new mw.Api();
    
    api.get({
        action: 'query',
        list: 'allpages',
        apprefix: searchPrefix,
        apnamespace: namespace,
        aplimit: 500
    }).done(function(data) {
        if (!data.query || !data.query.allpages || data.query.allpages.length === 0) {
            return;
        }
        
        // Filter out Archive subpages
        var pages = data.query.allpages.filter(function(page) {
            var subpageName = page.title.substring(pageName.length + 1);
            return !subpageName.startsWith('Archive');
        });
        
        if (pages.length === 0) {
            return;
        }
        
        var maxVisible = 5;
        var hiddenCount = Math.max(0, pages.length - maxVisible);
        
        var container = $('<div>')
            .attr('id', 'subpage-navigation')
            .css({
                'margin': '0.5em 0',
                'padding': '0.5em',
                // Use Codex design tokens so the box respects dark mode.
                'background': 'var(--background-color-neutral, #f8f9fa)',
                'border': '1px solid var(--border-color-base, #a2a9b1)',
                'font-size': '90%'
            });
        
        container.append($('<strong>').text('Subpages: '));
        var listSpan = $('<span class="subpage-list"></span>');
        var hiddenSpan = $('<span class="subpage-hidden" style="display:none;"></span>');
        container.append(listSpan).append(hiddenSpan);
        
        pages.forEach(function(page, idx) {
            var fullTitle = page.title;
            var subpageName = fullTitle.substring(pageName.length + 1);
            
            var link = $('<a>')
                .attr('href', mw.util.getUrl(fullTitle))
                .text(subpageName);
            var targetSpan = (idx < maxVisible) ? listSpan : hiddenSpan;
            targetSpan.append(link);
            var groupEnd =
                (idx === maxVisible - 1) ||
                (idx === pages.length - 1);
            if (!groupEnd) {
                targetSpan.append(' · ');
            }
        });
        
        if (pages.length > maxVisible) {
            var toggleSeparator = $('<span class="toggle-separator"> · </span>');
            container.append(toggleSeparator);
            var toggle = $('<a>')
                .attr('href', 'javascript:void(0)')
                .text('Show ' + hiddenCount + ' more')
                .on('click', function() {
                    var expanded = hiddenSpan.is(':visible');
                    if (expanded) {
                        hiddenSpan.hide();
                        $(this).text('Show ' + hiddenCount + ' more');
                        var first = hiddenSpan.contents().first();
                        if (first.text && first.text().trim() === '·') first.remove();
                    } else {
                        hiddenSpan.show();
                        $(this).text('Show less');
                        var first = hiddenSpan.contents().first();
                        if (!(first.text && first.text().trim() === '·')) {
                            hiddenSpan.prepend(' · ');
                        }
                        var last = hiddenSpan.contents().last();
                        if (last.text && last.text().trim() === '·') last.remove();
                    }
                });
            container.append(toggle);
        }
        
        $('#firstHeading').after(container);

        // Fire hook so Popups/Navigation Popups process the links in the container
        mw.hook('wikipage.content').fire(container);
        
    }).fail(function(error) {
        console.error('API error:', error);
    });
})();
// </nowiki>