Codeforces Font Changer

Change Codeforces Font.

K instalaci tototo skriptu si budete muset nainstalovat rozšíření jako Tampermonkey, Greasemonkey nebo Violentmonkey.

You will need to install an extension such as Tampermonkey to install this script.

K instalaci tohoto skriptu si budete muset nainstalovat rozšíření jako Tampermonkey nebo Violentmonkey.

K instalaci tohoto skriptu si budete muset nainstalovat rozšíření jako Tampermonkey nebo Userscripts.

You will need to install an extension such as Tampermonkey to install this script.

K instalaci tohoto skriptu si budete muset nainstalovat manažer uživatelských skriptů.

(Už mám manažer uživatelských skriptů, nechte mě ho nainstalovat!)

You will need to install an extension such as Stylus to install this style.

You will need to install an extension such as Stylus to install this style.

You will need to install an extension such as Stylus to install this style.

You will need to install a user style manager extension to install this style.

You will need to install a user style manager extension to install this style.

You will need to install a user style manager extension to install this style.

(Už mám manažer uživatelských stylů, nechte mě ho nainstalovat!)

// ==UserScript==
// @name         Codeforces Font Changer
// @name:zh-cn   Codeforces Font Changer
// @description  Change Codeforces Font.
// @match        *://*.codeforces.com/*
// @namespace    https://www.murasame-chan.me
// @license      MIT
// @grant        none
// @run-at       document-end
// @version      2.1
// ==/UserScript==
(function(){
    'use strict';
    const PAGE_FONT = 'Lato, "Noto Sans CJK SC", sans-serif, "Line Awesome Brands", iconfont';
    const CODE_FONT = '"Fira Code", "Cascadia Code", "JetBrains Mono", monospace';
    const MATH_FONT = '"KaTeX_Main", "KaTeX_Math", "Times New Roman", serif';
    const SKIP_CONTAINER_SELECTOR = [
        '.menu-list',
        '.main-menu-list',
        '.second-level-menu',
        '.second-level-menu-list',
        '.backLava',
        '.selectedLava',
        '.MathJax',
        '.mjx-container',
        '.katex'
    ].join(', ');
    const CODE_ANCHORS = 'code, pre, .CodeMirror, .monaco-editor, textarea, .ace-content, .ace_scroller';

    function isInsideSkippedContainer(node){
        if(!(node && node.nodeType === 1)) return false;
        try{ return !!node.closest(SKIP_CONTAINER_SELECTOR); }catch(e){ return false; }
    }

    function applyFontToElement(el){
        if(!el || el.nodeType !== 1) return;
        if(isInsideSkippedContainer(el)) return;
        try{
            if(el.closest && el.closest(CODE_ANCHORS)){
                el.style.setProperty('font-family', CODE_FONT, 'important');
                el.style.setProperty('font-variant-ligatures', 'common-ligatures', 'important');
                el.style.setProperty('-webkit-font-variant-ligatures', 'common-ligatures', 'important');
                el.style.setProperty('font-feature-settings', '"liga", "clig"', 'important');
                return;
            }
            if(el.matches && el.matches('.MathJax, .MathJax_Display, .MathJax_Preview, .mjx-container, .katex, .MJXp-math, .MJXp-mn')){
                el.style.setProperty('font-family', MATH_FONT, 'important');
                el.style.setProperty('font-variant-ligatures', 'normal', 'important');
                el.style.setProperty('-webkit-font-variant-ligatures', 'normal', 'important');
                el.style.setProperty('font-feature-settings', 'normal', 'important');
                return;
            }
            el.style.setProperty('font-family', PAGE_FONT, 'important');
            el.style.setProperty('font-variant-ligatures', 'normal', 'important');
            el.style.setProperty('-webkit-font-variant-ligatures', 'normal', 'important');
            el.style.setProperty('font-feature-settings', 'normal', 'important');
        }catch(e){}
    }

    function applyFontsToExisting(){
        const all = document.getElementsByTagName('*');
        for(let i=0;i<all.length;i++) applyFontToElement(all[i]);
    }

    function observeMutations(){
        const mo = new MutationObserver(mutations=>{
            for(const m of mutations){
                if(m.addedNodes && m.addedNodes.length){
                    m.addedNodes.forEach(node=>{
                        if(node.nodeType!==1) return;
                        if(isInsideSkippedContainer(node)) return;
                        applyFontToElement(node);
                        const elems = node.getElementsByTagName ? node.getElementsByTagName('*') : [];
                        for(let j=0;j<elems.length;j++) applyFontToElement(elems[j]);
                    });
                }
                if(m.type==='attributes' && m.target && m.target.nodeType===1){
                    applyFontToElement(m.target);
                }
            }
        });
        mo.observe(document.documentElement||document.body, { childList: true, subtree: true, attributes: true, attributeFilter: ['class','style'] });
    }

    function disableMathJaxMenu(){
        try{
            if(window.MathJax && window.MathJax.Hub && typeof window.MathJax.Hub.Config === 'function'){
                try{ window.MathJax.Hub.Config({ showMathMenu: false, showMathMenuMSIE: false }); }catch(e){}
            }
        }catch(e){}
        document.addEventListener('contextmenu', function(e){
            try{
                const tgt = e.target;
                if(!tgt || typeof tgt.closest!=='function') return;
                if(tgt.closest('.MathJax, .MathJax_Display, .MathJax_Preview, .mjx-container, .katex, .MJXp-math, .MJXp-mn')){
                    e.stopImmediatePropagation();
                }
            }catch(err){}
        }, true);
    }

    function ensureKaTeXCSS(){
        try{
            const hasKaTeX = Array.from(document.styleSheets).some(s=>{
                try{ return !!s.href && /katex/i.test(s.href); }catch(e){ return false; }
            }) || !!document.querySelector('link[href*="katex"]');
            if(!hasKaTeX){
                const link = document.createElement('link');
                link.rel = 'stylesheet';
                link.href = 'https://cdn.jsdelivr.net/npm/[email protected]/dist/katex.min.css';
                link.crossOrigin = 'anonymous';
                document.head.appendChild(link);
            }
        }catch(e){}
    }

    try{
        // Optional: Change KaTeX font to KaTeX_Main, KaTeX_Math
        // ensureKaTeXCSS();
        applyFontsToExisting();
        observeMutations();
        // Optional: Disable MathJax right-click menu
        // disableMathJaxMenu();
        console.info('Font changer active: code descendants forced to Fira Code.');
    }catch(e){}
})();