MediaWiki:Gadget-RcPopularPages.js

// Creates a list of popular pages on Special:RecentChanges
// by Espyo

$(function() {
    'use strict';

    const PAGES_TO_SHOW = 10;

    var popularListSpan = null;

    function addScanButton() {
        var popularSpan = document.createElement('span');
        document.querySelector('.rcoptions').appendChild(popularSpan);

        var popularLabelSpan = document.createElement('span');
        popularSpan.appendChild(popularLabelSpan);
        popularLabelSpan.innerHTML = 'Popular pages in this list: ';

        popularListSpan = document.createElement('span');
        popularSpan.appendChild(popularListSpan);

        var scanA = document.createElement('a');
        popularListSpan.appendChild(scanA);
        scanA.onclick = scan;
        scanA.innerHTML = '[Show]';
    }

    function scan() {
        var lines = document.querySelectorAll('div.mw-changeslist a.mw-changeslist-title');
        if(lines.length == 0) return;

        var editsByPage = {};

        for(var i = 0; i < lines.length; i++) {
            var page = lines[i].innerHTML;
            if(page in editsByPage) {
                editsByPage[page][1]++;
            } else {
                editsByPage[page] = [lines[i], 1];
            }
        }

        var pairs = Object.keys(editsByPage).map(function(key) {
            return [key, editsByPage[key][0], editsByPage[key][1]];
        });
        pairs.sort(function(a, b) {
            return b[2] - a[2];
        });

        popularListSpan.innerHTML = '';

        var pagesToShow = Math.min(PAGES_TO_SHOW, pairs.length);
        for(var p = 0; p < pagesToShow; p++) {
            var newLink = pairs[p][1].cloneNode();
            newLink.innerHTML = pairs[p][1].innerHTML;
            var text = ' (' + pairs[p][2] + ')';
            if(p < pagesToShow - 1) {
                text += ' | ';
            }
            popularListSpan.appendChild(newLink);
            popularListSpan.appendChild(document.createTextNode(text));
        }
    }

    if(!mw || mw.config.get('wgPageName') != 'Special:RecentChanges') return;

    addScanButton();
});