reveal.js

document.addEventListener('DOMContentLoaded', () => {
  const paperBody = document.querySelector('.paper-body');
  if (!paperBody) return;

  const cursor = document.createElement('div');
  cursor.className = 'llm-cursor';
  document.body.appendChild(cursor);

  function wrapWords(element) {
    const nodes = Array.from(element.childNodes);
    nodes.forEach(node => {
      if (node.nodeType === Node.TEXT_NODE) {
        const text = node.textContent;
        if (text.trim() === '') return;
        const fragment = document.createDocumentFragment();
        const words = text.split(/(\s+)/);
        words.forEach(word => {
          if (word.length === 0) return;
          if (word.trim() === '') {
            fragment.appendChild(document.createTextNode(word));
          } else {
            const span = document.createElement('span');
            span.className = 'word-wrapper';
            span.textContent = word;
            fragment.appendChild(span);
          }
        });
        element.replaceChild(fragment, node);
      } else if (node.nodeType === Node.ELEMENT_NODE && 
                 node.tagName !== 'SCRIPT' && 
                 node.tagName !== 'STYLE' && 
                 !node.classList.contains('proof-script')) {
        wrapWords(node);
      }
    });
  }

  wrapWords(paperBody);

  const queue = [];
  let isProcessing = false;
  const containers = Array.from(paperBody.querySelectorAll('p, h1, h2, h3, li, blockquote'));
  const revealedContainers = new Set();
  
  // Track active word for cursor repositioning on scroll
  let activeWord = null;

  function updateCursorPosition() {
    if (!activeWord || !cursor.classList.contains('active')) return;
    const rect = activeWord.getBoundingClientRect();
    cursor.style.position = 'fixed';
    cursor.style.left = `${rect.right}px`;
    cursor.style.top = `${rect.top}px`;
    cursor.style.height = `${rect.height}px`;
    cursor.style.width = '2px';
  }

  function checkVisibility() {
    const viewportHeight = window.innerHeight;
    containers.forEach(container => {
      if (revealedContainers.has(container)) return;
      const rect = container.getBoundingClientRect();
      if (rect.top < viewportHeight * 0.95) {
        revealedContainers.add(container);
        queue.push(container);
        if (!isProcessing) processQueue();
      }
    });
    // Ensure cursor follows scroll
    updateCursorPosition();
  }

  window.addEventListener('scroll', checkVisibility, { passive: true });
  setInterval(checkVisibility, 50); // High frequency check for smoother cursor
  checkVisibility();

  async function processQueue() {
    if (queue.length === 0) {
      isProcessing = false;
      cursor.classList.remove('active');
      activeWord = null;
      return;
    }
    isProcessing = true;
    const container = queue.shift();
    await revealWordsInContainer(container);
    processQueue();
  }

  function getDynamicDelay() {
    const viewportHeight = window.innerHeight;
    const hiddenWordsInView = document.querySelectorAll('.word-wrapper:not(.revealed)');
    let countInView = 0;
    hiddenWordsInView.forEach(word => {
      const rect = word.getBoundingClientRect();
      if (rect.top < viewportHeight && rect.bottom > 0) countInView++;
    });
    const minDelay = 4;
    const maxDelay = 60;
    const scaleFactor = 150;
    const ratio = Math.min(countInView / scaleFactor, 1);
    return maxDelay - (ratio * (maxDelay - minDelay));
  }

  async function revealWordsInContainer(container) {
    const words = Array.from(container.querySelectorAll('.word-wrapper:not(.revealed)'));
    if (words.length === 0) return;
    cursor.classList.add('active');
    
    for (const word of words) {
      activeWord = word;
      word.classList.add('revealing');
      updateCursorPosition();
      
      const baseDelay = getDynamicDelay();
      const delay = baseDelay + Math.random() * (baseDelay * 0.4);
      await new Promise(r => setTimeout(r, delay));
      
      word.classList.add('revealed');
      word.classList.remove('revealing');
      updateCursorPosition();
    }
  }
});