add basic theme upload functionality

src/interface/components/useVisibility.tsx

@@ -0,0 +1,34 @@
+import { useState, useEffect, useRef } from 'react';
+
+interface Options {
+  root?: Element | null;
+  rootMargin?: string;
+  threshold?: number | number[];
+}
+
+type UseVisibilityReturnType = [any | null, boolean];
+
+const useVisibility = (options: Options): UseVisibilityReturnType => {
+  const [isVisible, setIsVisible] = useState<boolean>(false);
+  const elementRef = useRef<Element | null>(null);
+
+  useEffect(() => {
+    const observer = new IntersectionObserver(([entry]) => {
+      setIsVisible(entry.isIntersecting);
+    }, options);
+
+    if (elementRef.current) {
+      observer.observe(elementRef.current);
+    }
+
+    return () => {
+      if (elementRef.current) {
+        observer.unobserve(elementRef.current);
+      }
+    };
+  }, [elementRef, options]);
+
+  return [elementRef, isVisible];
+};
+
+export default useVisibility;