(function() {
  console.log("loaded amsk-fix-tm");
  // 正则：匹配 “Arthrosamid” （整词、不分大小写），且后面没 ® 或 ®
  const RX = /\b(Arthrosamid)\b(?!\s*(?:®|®))/gi;
  const ATTRS = ['title', 'alt', 'placeholder', 'aria-label', 'data-tooltip'];

  // 简易 throttle：fn 最多每 interval 毫秒执行一次
  function throttle(fn, interval) {
    let last = 0, timer = null;
    return function(...args) {
      const now = Date.now();
      const remaining = interval - (now - last);
      if (remaining <= 0) {
        clearTimeout(timer);
        timer = null;
        last = now;
        fn.apply(this, args);
      } else if (!timer) {
        timer = setTimeout(() => {
          last = Date.now();
          timer = null;
          fn.apply(this, args);
        }, remaining);
      }
    };
  }

  // 给 el 或 el subtree 中的文本节点加 ®
  function replaceInTextNodes(root) {
    const walker = document.createTreeWalker(root, NodeFilter.SHOW_TEXT, null, false);
    let node;
    while (node = walker.nextNode()) {
      const parent = node.parentNode;
      if (parent && parent.dataset.arthroChecked) continue;
      const orig = node.nodeValue;
      const replaced = orig.replace(RX, (m, p1) => p1 + '®');
      if (replaced !== orig) {
        node.nodeValue = replaced;
      }
    }
  }

  // 给单个元素属性加 ®
  function replaceInAttributes(el) {
    if (el.dataset.arthroChecked) return;
    let changed = false;
    ATTRS.forEach(attr => {
      if (!el.hasAttribute(attr)) return;
      const val = el.getAttribute(attr);
      const newVal = val.replace(RX, (m, p1) => p1 + '®');
      if (newVal !== val) {
        el.setAttribute(attr, newVal);
        changed = true;
      }
    });
    if (changed) {
      el.dataset.arthroChecked = '1';
    }
  }

  // 对 root （元素节点或 document.body）做批量处理，并打标记
  function processRoot(root) {
    if (root.nodeType === 1) {
      replaceInAttributes(root);
      root.dataset.arthroChecked = '1';
    }
    replaceInTextNodes(root);
    if (root.querySelectorAll) {
      // 批量处理子元素属性
      ATTRS.forEach(attr => {
        root.querySelectorAll('[' + attr + ']').forEach(el => replaceInAttributes(el));
      });
    }
  }

  // 初次全页扫描（可拆帧以防大页面阻塞，这里简单一次跑完）
  function initialScan() {
    processRoot(document.body);
  }
  window.initialScan = initialScan;
  if (document.readyState === 'loading') {
    document.addEventListener('DOMContentLoaded', initialScan);
  } else {
    initialScan();
  }

  // 用节流合并频繁的 MutationObserver 回调
  const pending = new Set();
  function flushPending() {
    pending.forEach(node => processRoot(node));
    pending.clear();
  }
  const throttledFlush = throttle(flushPending, 100); // 每 100ms 最多执行一次

  // 观察新增节点和属性变化
  const observer = new MutationObserver(muts => {
    muts.forEach(m => {
      if (m.type === 'childList') {
        m.addedNodes.forEach(n => {
          if (n.nodeType === 1 || n.nodeType === 3) {
            pending.add(n.nodeType === 3 ? n.parentNode : n);
          }
        });
      } else if (m.type === 'attributes' && ATTRS.includes(m.attributeName)) {
        pending.add(m.target);
      }
    });
    throttledFlush();
  });
  observer.observe(document.body, {
    childList: true,
    subtree: true,
    attributes: true,
    attributeFilter: ATTRS
  });
})();