// ==UserScript==
// @name        YouTube /embed/ forwarder
// @description Forwards YouTube links to the youtube.com/embed/* page, so there's just the video in your window and nothing else.
// @namespace   https://greasyfork.org/en/users/1148791-vuccala
// @author      Vuccala
// @icon        https://archive.org/download/yt_icon/yt.png
// @match       *://*.youtube.com/*
// @match       *://*.youtu.be/*
// @run-at      document-start
// @version     0.4
// @grant       none
// @license     MIT

// @downloadURL https://update.greasyfork.icu/scripts/473082/YouTube%20embed%20forwarder.user.js
// @updateURL https://update.greasyfork.icu/scripts/473082/YouTube%20embed%20forwarder.meta.js
// ==/UserScript==

(function() {
    var embedBaseUrl = 'https://youtube.com/embed/';

    function getId(u) {
        var idMatch = /(?:[?&]v=|\/(?:embed\/|v\/|shorts\/))([^&?/]+)/.exec(u);
        return idMatch ? idMatch[1] : '';
    }

    function updateLinks(links) {
        links.forEach(function(link) {
            var linkHref = link.getAttribute('href');
            var videoIdMatch = /(?:[?&]v=|\/(?:embed\/|v\/|shorts\/))([^&?/]+)/.exec(linkHref);

            if (videoIdMatch) {
                var videoId = videoIdMatch[1];
                var embedUrl = embedBaseUrl + videoId;
                link.href = embedUrl;
            }
        });
    }

    function observeDOM() {
        var targetNode = document.body;

        var observer = new MutationObserver(function(mutationsList) {
            for (var mutation of mutationsList) {
                if (mutation.type === 'childList') {
                    var newLinks = mutation.addedNodes[0].querySelectorAll('a[href*="/watch?v="], a[href*="/shorts/"], a[href*="/watch?app=desktop&v="]');
                    updateLinks(newLinks);
                }
            }
        });

        var observerConfig = { childList: true, subtree: true };
        observer.observe(targetNode, observerConfig);
    }

    var url = window.location.href;

    if (url.includes('/watch?v=') || url.includes('/shorts/') || url.includes('/watch?app=desktop&v=')) {
        var videoId = getId(url);
        var newURL = embedBaseUrl + videoId;

        // Change the location to the new URL
        if (newURL !== url) {
            window.location.href = newURL;
        }
    } else {
        observeDOM();
    }
})();