Rewrite AvatarOverlay component with React hooks

app/javascript/mastodon/components/__tests__/__snapshots__/avatar_overlay-test.jsx.snap

@@ -3,6 +3,8 @@
 exports[`<AvatarOverlay renders a overlay avatar 1`] = `
 <div
   className="account__avatar-overlay"
+  onMouseEnter={[Function]}
+  onMouseLeave={[Function]}
   style={
     {
       "height": 46,
@@ -15,8 +17,6 @@ exports[`<AvatarOverlay renders a overlay avatar 1`] = `
   >
     <div
       className="account__avatar"
-      onMouseEnter={[Function]}
-      onMouseLeave={[Function]}
       style={
         {
           "height": "36px",
@@ -35,8 +35,6 @@ exports[`<AvatarOverlay renders a overlay avatar 1`] = `
   >
     <div
       className="account__avatar"
-      onMouseEnter={[Function]}
-      onMouseLeave={[Function]}
       style={
         {
           "height": "24px",

app/javascript/mastodon/components/avatar_overlay.tsx

@@ -0,0 +1,51 @@
+import React from 'react';
+import type { Account } from '../../types/resources';
+import { useHovering } from '../../hooks/useHovering';
+import { autoPlayGif } from '../initial_state';
+
+type Props = {
+  account: Account;
+  friend: Account;
+  size?: number;
+  baseSize?: number;
+  overlaySize?: number;
+};
+
+export const AvatarOverlay: React.FC<Props> = ({
+  account,
+  friend,
+  size = 46,
+  baseSize = 36,
+  overlaySize = 24,
+}) => {
+  const { hovering, handleMouseEnter, handleMouseLeave } = useHovering(autoPlayGif);
+  const accountSrc = hovering ? account?.get('avatar') : account?.get('avatar_static');
+  const friendSrc = hovering ? friend?.get('avatar') : friend?.get('avatar_static');
+
+  return (
+    <div
+      className='account__avatar-overlay' style={{ width: size, height: size }}
+      onMouseEnter={handleMouseEnter}
+      onMouseLeave={handleMouseLeave}
+    >
+      <div className='account__avatar-overlay-base'>
+        <div
+          className='account__avatar'
+          style={{ width: `${baseSize}px`, height: `${baseSize}px` }}
+        >
+          {accountSrc && <img src={accountSrc} alt={account?.get('acct')} />}
+        </div>
+      </div>
+      <div className='account__avatar-overlay-overlay'>
+        <div
+          className='account__avatar'
+          style={{ width: `${overlaySize}px`, height: `${overlaySize}px` }}
+        >
+          {friendSrc && <img src={friendSrc} alt={friend?.get('acct')} />}
+        </div>
+      </div>
+    </div>
+  );
+};
+
+export default AvatarOverlay;