// Paste this whole block into the browser console on your phone.
// It will create a fullscreen tap area that opens a file picker,
// read the chosen file as text, and inject it into the page as a <script> element.

(function createFullscreenFileInjector() {
  // Prevent double-run
  if (window.__fullscreenFileInjectorInstalled) {
    console.log('Fullscreen file injector already installed.');
    return;
  }
  window.__fullscreenFileInjectorInstalled = true;

  // Create hidden file input
  const input = document.createElement('input');
  input.type = 'file';
  input.accept = '.js,.mjs,.txt,application/javascript,text/*'; // allow js and plain text
  input.multiple = false;
  input.style.display = 'none';
  document.documentElement.appendChild(input);

  // Create fullscreen tap button
  const btn = document.createElement('button');
  btn.id = '__fs_file_inject_btn';
  btn.innerText = 'Tap to choose file\n(Will inject as <script>)';
  Object.assign(btn.style, {
    position: 'fixed',
    inset: '0',                 // full-screen
    width: '100vw',
    height: '100vh',
    margin: '0',
    padding: '0',
    border: 'none',
    background: 'linear-gradient(180deg, rgba(0,0,0,0.55), rgba(0,0,0,0.35))',
    color: 'white',
    fontSize: '5vw',
    lineHeight: '1.2',
    display: 'flex',
    alignItems: 'center',
    justifyContent: 'center',
    textAlign: 'center',
    whiteSpace: 'pre-line',
    zIndex: String(2147483647), // very top
    touchAction: 'manipulation',
    WebkitAppearance: 'none',
    outline: 'none',
    userSelect: 'none',
    -webkitUserSelect: 'none'
  });

  // Small hint for removing the button (long-press)
  const hint = document.createElement('div');
  hint.innerText = 'Long-press here to remove';
  Object.assign(hint.style, {
    position: 'absolute',
    bottom: '6vh',
    fontSize: '3.2vw',
    opacity: '0.85'
  });
  btn.appendChild(hint);

  // Append button
  document.documentElement.appendChild(btn);

  // Helper: small toast
  function toast(msg, timeout = 2500) {
    const t = document.createElement('div');
    Object.assign(t.style, {
      position: 'fixed',
      left: '50%',
      transform: 'translateX(-50%)',
      bottom: '8vh',
      background: 'rgba(0,0,0,0.75)',
      color: 'white',
      padding: '8px 12px',
      borderRadius: '8px',
      zIndex: String(2147483647),
      fontSize: '3.6vw',
      maxWidth: '90vw',
      textAlign: 'center'
    });
    t.textContent = msg;
    document.documentElement.appendChild(t);
    setTimeout(() => t.remove(), timeout);
  }

  // Click handler: open file picker
  btn.addEventListener('click', () => input.click(), { passive: true });

  // Long-press to remove the fullscreen button (so you can remove it on mobile)
  (function addLongPressRemoval(el, onRemove) {
    let timer = null;
    let startY = null;
    const start = (e) => {
      startY = e.touches ? e.touches[0].clientY : e.clientY;
      timer = setTimeout(() => {
        onRemove();
        timer = null;
      }, 800); // long-press threshold
    };
    const cancel = () => {
      if (timer) { clearTimeout(timer); timer = null; }
    };
    el.addEventListener('touchstart', start, { passive: true });
    el.addEventListener('mousedown', start);
    el.addEventListener('touchmove', (e) => {
      if (!startY) return;
      if (Math.abs(e.touches[0].clientY - startY) > 20) cancel();
    }, { passive: true });
    ['mouseup','mouseleave','touchend','touchcancel'].forEach(ev => el.addEventListener(ev, cancel));
  })(btn, () => {
    btn.remove();
    input.remove();
    delete window.__fullscreenFileInjectorInstalled;
    toast('Fullscreen button removed');
    console.log('Fullscreen file injector removed by user.');
  });

  // Read file and inject as <script>
  input.addEventListener('change', async (ev) => {
    const f = ev.target.files && ev.target.files[0];
    if (!f) {
      toast('No file selected');
      return;
    }

    try {
      // Prefer file.text() (modern). Fallback to FileReader if needed.
      let text;
      if (typeof f.text === 'function') {
        text = await f.text();
      } else {
        text = await new Promise((res, rej) => {
          const fr = new FileReader();
          fr.onerror = () => rej(fr.error || new Error('FileReader error'));
          fr.onload = () => res(String(fr.result));
          fr.readAsText(f, 'utf-8');
        });
      }

      // Create script element and inject
      const script = document.createElement('script');
      // If you want the script to execute in module scope, uncomment next line:
      // script.type = 'module';
      // Put file content directly
      script.textContent = text;

      // Optionally add an attribute to find/remove it later
      script.setAttribute('data-injected-by', 'fullscreen-file-injector');

      document.documentElement.appendChild(script);

      toast('Script injected ✔');
      console.log('Injected script from file:', f.name, '\n---begin---\n', text.slice(0, 1000), '\n---end-preview---');
      // remove the fullscreen button so it doesn't block the page
      btn.remove();
      input.remove();
      delete window.__fullscreenFileInjectorInstalled;
    } catch (err) {
      console.error('Failed to read or inject file:', err);
      toast('Error: ' + (err && err.message ? err.message : 'unknown'));
    }
  }, { passive: true });

  // Informational console message
  console.log('Fullscreen file injector installed. Tap the screen to pick a file. Long-press the screen to remove the button without picking a file.');
})();