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1 files changed, 45 insertions, 0 deletions

diff --git a/FrontEnd/src/utilities/hooks/useScrollToBottom.ts b/FrontEnd/src/utilities/hooks/useScrollToBottom.ts
new file mode 100644
index 00000000..f6780d9f
--- /dev/null
+++ b/FrontEnd/src/utilities/hooks/useScrollToBottom.ts
@@ -0,0 +1,45 @@
+import React from "react";
+import { fromEvent } from "rxjs";
+import { filter, throttleTime } from "rxjs/operators";
+
+function useScrollToBottom(
+  handler: () => void,
+  enable = true,
+  option = {
+    maxOffset: 5,
+    throttle: 1000,
+  }
+): void {
+  const handlerRef = React.useRef<(() => void) | null>(null);
+
+  React.useEffect(() => {
+    handlerRef.current = handler;
+
+    return () => {
+      handlerRef.current = null;
+    };
+  }, [handler]);
+
+  React.useEffect(() => {
+    const subscription = fromEvent(window, "scroll")
+      .pipe(
+        filter(
+          () =>
+            window.scrollY >=
+            document.body.scrollHeight - window.innerHeight - option.maxOffset
+        ),
+        throttleTime(option.throttle)
+      )
+      .subscribe(() => {
+        if (enable) {
+          handlerRef.current?.();
+        }
+      });
+
+    return () => {
+      subscription.unsubscribe();
+    };
+  }, [enable, option.maxOffset, option.throttle]);
+}
+
+export default useScrollToBottom;