Copy a math equation to Word

Double-click on a formula on a webpage to copy it to the clipboard, then paste it into Microsoft Word
换行
// ==UserScript==
// @name         Copy a math equation to Word
// @namespace    http://tampermonkey.net/
// @version      1.0
// @license      GPLv3
// @description  Double-click on a formula on a webpage to copy it to the clipboard, then paste it into Microsoft Word
// @author       Bui Quoc Dung
// @match        *://*.wikipedia.org/*
// @match        *://*.chatgpt.com/*
// @match        *://*.stackexchange.com/*
// @match        *://*.deepseek.com/*
// ==/UserScript==

(function () {
    'use strict';

    // Insert CSS styles
    const css = `
        .mathml-tooltip { position: fixed; background-color: rgba(0, 0, 0, 0.7); color: #fff; padding: 5px 10px; border-radius: 5px; font-size: 11px; z-index: 1000; opacity: 0; transition: opacity 0.2s; pointer-events: none; }
        .mathml-copy-success { position: absolute; background-color: rgba(0, 0, 0, 0.7); color: #fff; padding: 5px 10px; border-radius: 5px; font-size: 12px; z-index: 1000; opacity: 1; transition: opacity 0.5s; pointer-events: none; }
    `;
    const styleSheet = document.createElement("style");
    styleSheet.type = "text/css";
    styleSheet.innerText = css;
    document.head.appendChild(styleSheet);

    // Create tooltip element
    const tooltip = document.createElement('div');
    tooltip.classList.add('mathml-tooltip');
    document.body.appendChild(tooltip);

    function getTarget(url) {
        let target = { elementSelector: '', getMathMLString: null };

        function extractMathML(element) {
            let mathML = element.querySelector('math');
            return mathML ? mathML.outerHTML : null;
        }

        if (url.includes('wikipedia.org')) {
            target.elementSelector = 'span.mwe-math-element';
            target.getMathMLString = extractMathML;
        } else if (url.includes('chatgpt.com') || url.includes('deepseek.com')) {
            target.elementSelector = 'span.katex';
            target.getMathMLString = extractMathML;
        } else if (url.includes('stackexchange.com')) {
            target.elementSelector = 'span.math-container';
            target.getMathMLString = extractMathML;
        }

        return target.elementSelector ? target : null;
    }

    function addHandler() {
        let target = getTarget(window.location.href);
        if (!target) return;

        let tooltipTimeout;
        document.querySelectorAll(target.elementSelector).forEach(element => {
            element.addEventListener('mouseenter', function () {
                element.style.cursor = "pointer";
                tooltipTimeout = setTimeout(function () {
                    tooltip.textContent = "Double click to copy MathML";
                    const rect = element.getBoundingClientRect();
                    tooltip.style.left = `${rect.left}px`;
                    tooltip.style.top = `${rect.top - tooltip.offsetHeight - 5}px`;
                    tooltip.style.display = 'block';
                    tooltip.style.opacity = '0.8';
                }, 1000);
            });

            element.addEventListener('mouseleave', function () {
                element.style.cursor = "auto";
                clearTimeout(tooltipTimeout);
                tooltip.style.display = 'none';
                tooltip.style.opacity = '0';
            });

            element.ondblclick = function (event) {
                const mathMLString = target.getMathMLString(element);
                if (mathMLString !== null) {
                    navigator.clipboard.writeText(mathMLString).then(() => {
                        showCopySuccessTooltip(event);
                    });
                }
                window.getSelection().removeAllRanges();
            };
        });
    }

    function showCopySuccessTooltip(event) {
        const copyTooltip = document.createElement("div");
        copyTooltip.className = "mathml-copy-success";
        copyTooltip.innerText = "Copied";
        document.body.appendChild(copyTooltip);

        const rect = event.target.getBoundingClientRect();
        copyTooltip.style.left = `${rect.left + window.scrollX}px`;
        copyTooltip.style.top = `${rect.top + window.scrollY - 25}px`;

        setTimeout(() => {
            copyTooltip.style.opacity = "0";
            setTimeout(() => {
                document.body.removeChild(copyTooltip);
            }, 500);
        }, 1000);
    }

    document.addEventListener('DOMContentLoaded', addHandler);
    new MutationObserver(addHandler).observe(document.documentElement, { childList: true, subtree: true });
})();