Feat: Extract keyboard layout resizing helpers

src/keyboard.js

@@ -0,0 +1,24 @@
+import { el } from './dom.js';
+
+export function kbUpdate() {
+  const vv = window.visualViewport;
+  const overlap = vv ? Math.max(0, (window.innerHeight - (vv.height + vv.offsetTop))) : 0;
+  document.documentElement.style.setProperty('--kb', overlap + 'px');
+  const fh = el.footer.getBoundingClientRect().height;
+  document.documentElement.style.setProperty('--footer-h', fh + 'px');
+  el.footer.style.transform = 'translateY(' + (-overlap) + 'px)';
+  el.chat.style.scrollPaddingBottom = (fh + overlap + 16) + 'px';
+}
+
+export function kbBind() {
+  if (window.visualViewport) {
+    ['resize', 'scroll'].forEach(ev => window.visualViewport.addEventListener(ev, () => kbUpdate(), { passive: true }));
+  }
+  window.$(window).on('resize orientationchange', () => setTimeout(kbUpdate, 50));
+  window.$(el.input).on('focus click', () => {
+    setTimeout(() => {
+      kbUpdate();
+      el.input.scrollIntoView({ block: 'nearest', behavior: 'smooth' });
+    }, 0);
+  });
+}