Google to DuckDuckGo Redirector

goog2ddgredirect.js

// ==UserScript==
// @name         Google/Bing to DuckDuckGo Redirector
// @namespace    http://smugzombie.com
// @version      1.1
// @description  Redirects Google/Bing searches to DuckDuckGo.
// @author       Ron Egli <[email protected]> (github.com/smugzombie)
// @match        *://www.google.com/*
// @match        *://www.bing.com/*
// @grant        none
// ==/UserScript==

(function() {
    'use strict';

    const googleQueryPattern = /^https:\/\/www\.google\.com\/search\?q=(.*)$/;
    const bingQueryPattern = /^https:\/\/www\.bing\.com\/search\?q=(.*)$/;

    function redirectIfNeeded() {
        const currentUrl = window.location.href;
        let match;

        if (currentUrl.match(googleQueryPattern)) {
            match = currentUrl.match(googleQueryPattern);
            if (match) {
                const duckDuckGoUrl = `https://duckduckgo.com/?q=${match[1]}`;
                window.location.replace(duckDuckGoUrl);
            } else if (currentUrl === "https://www.google.com/") {
                window.location.replace("https://duckduckgo.com");
            }
        } else if (currentUrl.match(bingQueryPattern)) {
            match = currentUrl.match(bingQueryPattern);
            if (match) {
                const duckDuckGoUrl = `https://duckduckgo.com/?q=${match[1]}`;
                window.location.replace(duckDuckGoUrl);
            } else if (currentUrl === "https://www.bing.com/") {
                window.location.replace("https://duckduckgo.com");
            }
        }
    }

    // Run the redirect check when the script is loaded
    redirectIfNeeded();

    // Observe changes in the URL to handle single-page navigation in Google and Bing
    const observer = new MutationObserver(redirectIfNeeded);
    observer.observe(document, { childList: true, subtree: true });
})();