Get all *.github.io and github.com/* links

hn-get-github-links.js

(function setupGithubLinkCollectorUI() {
  // === Get all <a href="..."> values from the page ===
  function getAllAnchors() {
    return Array.from(document.querySelectorAll('a[href]')).map(a => a.href);
  }

  // === Extract only the root of *.github.io links (e.g. https://user.github.io) ===
  function extractGithubIoRoots(hrefs) {
    return [...new Set(
      hrefs
        .filter(href => href.includes('.github.io'))
        .map(href => {
          try {
            const url = new URL(href);
            return `${url.protocol}//${url.host}`; // Remove path, keep root
          } catch {
            return null;
          }
        })
        .filter(Boolean)
    )];
  }

  // === Extract only the username root of github.com links (e.g. https://github.com/user) ===
  function extractGithubComUserLinks(hrefs) {
    return [...new Set(
      hrefs
        .filter(href => href.includes('github.com/'))
        .map(href => {
          try {
            const url = new URL(href);
            const parts = url.pathname.split('/').filter(Boolean); // Removes empty strings
            return parts.length >= 1
              ? `${url.protocol}//${url.host}/${parts[0]}` // Keep only first path part (username)
              : null;
          } catch {
            return null;
          }
        })
        .filter(Boolean)
    )];
  }

  // === Display list of links as clickable <a> elements ===
  function displayLinks(links, container) {
    container.innerHTML = ''; // Clear previous results
    links.forEach(link => {
      const a = document.createElement('a');
      a.href = link;
      a.textContent = link;
      a.target = '_blank'; // Open in new tab
      a.style.display = 'block';
      container.appendChild(a);
    });
  }

  // === Handle click on "Collect *.github.io" button ===
  function handleGithubIoClick(outputContainer) {
    const hrefs = getAllAnchors();
    const links = extractGithubIoRoots(hrefs);
    console.log('github.io links:', links);
    displayLinks(links, outputContainer);
  }

  // === Handle click on "Collect github.com" button ===
  function handleGithubComClick(outputContainer) {
    const hrefs = getAllAnchors();
    const links = extractGithubComUserLinks(hrefs);
    console.log('github.com user links:', links);
    displayLinks(links, outputContainer);
  }

  // === Build the UI and inject it into the page ===
  function createCollectorUI() {
    // Remove old UI if already added
    const existing = document.getElementById('github-link-collector');
    if (existing) existing.remove();

    // Create wrapper box
    const wrapper = document.createElement('div');
    wrapper.id = 'github-link-collector';
    Object.assign(wrapper.style, {
      position: 'fixed',
      top: '10px',
      right: '10px',
      backgroundColor: 'white',
      border: '1px solid #888',
      padding: '12px',
      zIndex: 10000,
      fontSize: '14px',
      fontFamily: 'sans-serif',
      maxHeight: '90vh',
      overflowY: 'auto'
    });

    // Output area to display links
    const output = document.createElement('div');
    output.style.marginTop = '10px';

    // Create first button
    const btnIo = document.createElement('button');
    btnIo.textContent = 'Collect *.github.io links';
    btnIo.style.display = 'block';
    btnIo.style.marginBottom = '8px';
    btnIo.onclick = () => handleGithubIoClick(output);

    // Create second button
    const btnCom = document.createElement('button');
    btnCom.textContent = 'Collect github.com user links';
    btnCom.style.display = 'block';
    btnCom.style.marginBottom = '8px';
    btnCom.onclick = () => handleGithubComClick(output);

    // Add buttons and output to wrapper, add wrapper to page
    wrapper.appendChild(btnIo);
    wrapper.appendChild(btnCom);
    wrapper.appendChild(output);
    document.body.appendChild(wrapper);
  }

  // === Initialize the UI ===
  createCollectorUI();
})();