make useInterval function

src/components/Tetris/index.js

@@ -4,6 +4,7 @@ import './style.css';
 // Custom hooks
 import usePlayer from '../../hooks/usePlayer';
 import useStage from '../../hooks/useStage';
+import useInterval from '../../hooks/useInterval';
 
 // Components
 import Stage from '../Stage';
@@ -47,6 +48,10 @@ const Tetris = () => {
     }
   };
 
+  useInterval(() => {
+    drop();
+  }, dropTime);
+
   return (
     <div className="tetris" onKeyDown={(e) => move(e)}>
       <Stage stage={stage} />

src/hooks/useInterval.js

@@ -0,0 +1,14 @@
+import { useEffect } from 'react';
+
+const useInterval = (callback, delay) => {
+  useEffect(() => {
+    if (delay !== null) {
+      const id = setInterval(callback, delay);
+      return () => {
+        clearInterval(id);
+      };
+    }
+  }, [callback, delay]);
+};
+
+export default useInterval;