function autoLockPlaylist() {
  const playlistLength = document.querySelector('#pllength');
  const config = {
    characterData: true,
    childList: true,
    subtree: true,
  };
  const observer = new MutationObserver(([mutation], obs) => {
    const newText = mutation.target.textContent || mutation.target.nodeValue;
    let totalSeconds = 0;

    if (typeof newText === 'string') {
      const trim = newText.trim();
      // テキストが 00:00 または 00:00:00 の形式であることを確認
      if (/^\d{2}:\d{2}$/.test(trim)) {
        const [minutes, seconds] = trim.split(':').map(Number);
        totalSeconds = minutes * 60 + seconds;
      } else if (/^\d{2}:\d{2}:\d{2}$/.test(trim)) {
        const [hours, minutes, seconds] = trim.split(':').map(Number);
        totalSeconds = hours * 3600 + minutes * 60 + seconds;
      }
      // 90分以上かをチェック (5400秒)
      if (totalSeconds >= 5400) {
        const lockBtnElm = document.querySelector('#qlockbtn');
        const unlockIconElm = lockBtnElm?.querySelector('.glyphicon-ok');

        if (lockBtnElm && unlockIconElm) {
          lockBtnElm?.click();
        }
      }
    }
  });

  if (playlistLength) {
    observer.observe(playlistLength, config);
  }
}
autoLockPlaylist();