youtube-music/plugins/lyrics-genius/front.js

const { ipcRenderer } = require('electron');
const is = require('electron-is');

module.exports = () => {
  ipcRenderer.on('update-song-info', (_, extractedSongInfo) => setTimeout(() => {
    const tabList = document.querySelectorAll('tp-yt-paper-tab');
    const tabs = {
      upNext: tabList[0],
      lyrics: tabList[1],
      discover: tabList[2],
    };

    // Check if disabled
    if (!tabs.lyrics?.hasAttribute('disabled')) {
      return;
    }

    let hasLyrics = true;

    const lyrics = ipcRenderer.sendSync(
      'search-genius-lyrics',
      extractedSongInfo,
    );
    if (!lyrics) {
      // Delete previous lyrics if tab is open and couldn't get new lyrics
      checkLyricsContainer(() => {
        hasLyrics = false;
        setTabsOnclick(undefined);
      });
      return;
    }

    if (is.dev()) {
      console.log('Fetched lyrics from Genius');
    }

    enableLyricsTab();

    setTabsOnclick(enableLyricsTab);

    checkLyricsContainer();

    tabs.lyrics.addEventListener('click', () => {
      const tabContainer = document.querySelector('ytmusic-tab-renderer');
      const observer = new MutationObserver((_, observer) => {
        checkLyricsContainer(() => observer.disconnect());
      });
      observer.observe(tabContainer, {
        attributes: true,
        childList: true,
        subtree: true,
      });
    });

    function checkLyricsContainer(callback = () => {
    }) {
      const lyricsContainer = document.querySelector(
        '[page-type="MUSIC_PAGE_TYPE_TRACK_LYRICS"] > ytmusic-message-renderer',
      );
      if (lyricsContainer) {
        callback();
        setLyrics(lyricsContainer);
      }
    }

    function setLyrics(lyricsContainer) {
      lyricsContainer.innerHTML = `<div id="contents" class="style-scope ytmusic-section-list-renderer description ytmusic-description-shelf-renderer genius-lyrics">
			 		${
        hasLyrics
          ? lyrics.replaceAll(/\r\n|\r|\n/g, '<br/>')
          : 'Could not retrieve lyrics from genius'
      }

				</div>
				<yt-formatted-string class="footer style-scope ytmusic-description-shelf-renderer" style="align-self: baseline"></yt-formatted-string>`;
      if (hasLyrics) {
        lyricsContainer.querySelector('.footer').textContent = 'Source: Genius';
        enableLyricsTab();
      }
    }

    function setTabsOnclick(callback) {
      for (const tab of [tabs.upNext, tabs.discover]) {
        if (tab) {
          tab.addEventListener('click', callback);
        }
      }
    }

    function enableLyricsTab() {
      tabs.lyrics.removeAttribute('disabled');
      tabs.lyrics.removeAttribute('aria-disabled');
    }
  }, 500));
};