feat: add onHtmxLoad and closestFocusable utilities

static/utils.ts

@@ -20,3 +20,23 @@ export const onReady = (fn: () => void): void => {
 
   fn();
 };
+
+export const onHtmxLoad = (fn: (root: Element) => void): void => {
+  onReady(() => {
+    fn(document.body);
+    document.body.addEventListener("htmx:load", (event: Event) => {
+      const detail = event as CustomEvent<{ elt?: Element }>;
+      const root = detail.detail?.elt;
+      if (root instanceof Element) {
+        fn(root);
+      }
+    });
+  });
+};
+
+export const closestFocusable = (root: ParentNode): HTMLElement | null => {
+  const selector =
+    'button:not([disabled]), [href], input:not([disabled]), select:not([disabled]), textarea:not([disabled]), [tabindex]:not([tabindex="-1"])';
+  const node = root.querySelector<HTMLElement>(selector);
+  return node instanceof HTMLElement ? node : null;
+};