refactor(chat): use stick-to-bottom for message scrolling

bun.lock

@@ -81,6 +81,7 @@
         "tailwind-merge": "^3.0.1",
         "tailwindcss-animate": "^1.0.7",
         "tar-stream": "^3.1.7",
+        "use-stick-to-bottom": "^1.1.4",
         "uuid": "^11.1.0",
         "vaul": "^1.1.2",
         "vscode-languageclient": "^9.0.1",
@@ -2137,6 +2138,8 @@
 
     "use-sidecar": ["use-sidecar@1.1.3", "https://registry.npmmirror.com/use-sidecar/-/use-sidecar-1.1.3.tgz", { "dependencies": { "detect-node-es": "^1.1.0", "tslib": "^2.0.0" }, "peerDependencies": { "@types/react": "*", "react": "^16.8.0 || ^17.0.0 || ^18.0.0 || ^19.0.0 || ^19.0.0-rc" }, "optionalPeers": ["@types/react"] }, "sha512-Fedw0aZvkhynoPYlA5WXrMCAMm+nSWdZt6lzJQ7Ok8S6Q+VsHmHpRWndVRJ8Be0ZbkfPc5LRYH+5XrzXcEeLRQ=="],
 
+    "use-stick-to-bottom": ["use-stick-to-bottom@1.1.4", "", { "peerDependencies": { "react": "^16.8.0 || ^17.0.0 || ^18.0.0 || ^19.0.0" } }, "sha512-2w/lydkrwhWMv1vCaEhYbzMDhgbwIodHpAHPV0/xKJErRkbjDEUe1EWmvr6Fwb+qhiERjc1EWgAEZaSaF69CpA=="],
+
     "use-sync-external-store": ["use-sync-external-store@1.5.0", "https://registry.npmmirror.com/use-sync-external-store/-/use-sync-external-store-1.5.0.tgz", { "peerDependencies": { "react": "^16.8.0 || ^17.0.0 || ^18.0.0 || ^19.0.0" } }, "sha512-Rb46I4cGGVBmjamjphe8L/UnvJD+uPPtTkNvX5mZgqdbavhI4EbgIWJiIHXJ8bc/i9EQGPRh4DwEURJ552Do0A=="],
 
     "util-deprecate": ["util-deprecate@1.0.2", "https://registry.npmmirror.com/util-deprecate/-/util-deprecate-1.0.2.tgz", {}, "sha512-EPD5q1uXyFxJpCrLnCc1nHnq3gOa6DZBocAIiI2TaSCA7VCJ1UJDMagCzIkXNsUYfD1daK//LTEQ8xiIbrHtcw=="],

package.json

@@ -90,6 +90,7 @@
     "tailwind-merge": "^3.0.1",
     "tailwindcss-animate": "^1.0.7",
     "tar-stream": "^3.1.7",
+    "use-stick-to-bottom": "^1.1.4",
     "uuid": "^11.1.0",
     "vaul": "^1.1.2",
     "vscode-languageclient": "^9.0.1",

src/components/ui/chat/chat-message-list.tsx

@@ -1,57 +1,59 @@
 import * as React from "react";
 import { ArrowDown } from "lucide-react";
+import { StickToBottom, useStickToBottomContext } from "use-stick-to-bottom";
 import { Button } from "@/components/ui/button";
-import { useAutoScroll } from "@/components/ui/chat/hooks/useAutoScroll";
 
 interface ChatMessageListProps extends React.HTMLAttributes<HTMLDivElement> {
   smooth?: boolean;
 }
 
-const ChatMessageList = React.forwardRef<HTMLDivElement, ChatMessageListProps>(
-  // eslint-disable-next-line @typescript-eslint/no-unused-vars
-  ({ className, children, smooth = false, ...props }, _ref) => {
-    const {
-      scrollRef,
-      isAtBottom,
-      // eslint-disable-next-line @typescript-eslint/no-unused-vars
-      autoScrollEnabled,
-      scrollToBottom,
-      disableAutoScroll,
-    } = useAutoScroll({
-      smooth,
-      content: children,
-    });
+const ScrollToBottomButton = () => {
+  const { isAtBottom, scrollToBottom } = useStickToBottomContext();
+
+  if (isAtBottom) {
+    return null;
+  }
 
   return (
-      <div className="relative w-full h-full">
-        <div
-          className={`flex flex-col w-full h-full p-4 overflow-y-auto ${className}`}
-          ref={scrollRef}
-          onWheel={disableAutoScroll}
-          onTouchMove={disableAutoScroll}
-          {...props}
-        >
-          <div className="flex flex-col gap-6">{children}</div>
-        </div>
-
-        {!isAtBottom && (
     <Button
       onClick={() => {
         scrollToBottom();
       }}
       size="icon"
       variant="outline"
-            className="absolute bottom-2 left-1/2 transform -translate-x-1/2 inline-flex rounded-full shadow-md"
+      className="absolute bottom-2 left-1/2 inline-flex -translate-x-1/2 rounded-full shadow-md"
       aria-label="Scroll to bottom"
     >
       <ArrowDown className="h-4 w-4" />
     </Button>
-        )}
-      </div>
-    );
-  }
   );
+};
 
-ChatMessageList.displayName = "ChatMessageList";
+const ChatMessageList = ({
+  className,
+  children,
+  smooth = false,
+  ...props
+}: ChatMessageListProps) => {
+  const animation = smooth ? "smooth" : "instant";
+
+  return (
+    <StickToBottom
+      className="relative h-full w-full"
+      initial="instant"
+      resize={animation}
+    >
+      <StickToBottom.Content
+        className="flex flex-col gap-6"
+        scrollClassName={`h-full w-full p-4 ${className ?? ""}`}
+        {...props}
+      >
+        {children}
+      </StickToBottom.Content>
+
+      <ScrollToBottomButton />
+    </StickToBottom>
+  );
+};
 
 export { ChatMessageList };

src/components/ui/chat/hooks/useAutoScroll.tsx

@@ -1,135 +0,0 @@
-// @hidden
-import { useCallback, useEffect, useRef, useState } from "react";
-
-interface ScrollState {
-  isAtBottom: boolean;
-  autoScrollEnabled: boolean;
-}
-
-interface UseAutoScrollOptions {
-  offset?: number;
-  smooth?: boolean;
-  content?: React.ReactNode;
-}
-
-export function useAutoScroll(options: UseAutoScrollOptions = {}) {
-  const { offset = 20, smooth = false, content } = options;
-  const scrollRef = useRef<HTMLDivElement>(null);
-  const lastContentHeight = useRef(0);
-  const userHasScrolled = useRef(false);
-
-  const [scrollState, setScrollState] = useState<ScrollState>({
-    isAtBottom: true,
-    autoScrollEnabled: true,
-  });
-
-  const checkIsAtBottom = useCallback(
-    (element: HTMLElement) => {
-      const { scrollTop, scrollHeight, clientHeight } = element;
-      const distanceToBottom = Math.abs(
-        scrollHeight - scrollTop - clientHeight
-      );
-      return distanceToBottom <= offset;
-    },
-    [offset]
-  );
-
-  const scrollToBottom = useCallback(
-    (instant?: boolean) => {
-      if (!scrollRef.current) return;
-
-      const targetScrollTop =
-        scrollRef.current.scrollHeight - scrollRef.current.clientHeight;
-
-      if (instant) {
-        scrollRef.current.scrollTop = targetScrollTop;
-      } else {
-        scrollRef.current.scrollTo({
-          top: targetScrollTop,
-          behavior: smooth ? "smooth" : "auto",
-        });
-      }
-
-      setScrollState({
-        isAtBottom: true,
-        autoScrollEnabled: true,
-      });
-      userHasScrolled.current = false;
-    },
-    [smooth]
-  );
-
-  const handleScroll = useCallback(() => {
-    if (!scrollRef.current) return;
-
-    const atBottom = checkIsAtBottom(scrollRef.current);
-
-    setScrollState((prev) => ({
-      isAtBottom: atBottom,
-      // Re-enable auto-scroll if at the bottom
-      autoScrollEnabled: atBottom ? true : prev.autoScrollEnabled,
-    }));
-  }, [checkIsAtBottom]);
-
-  useEffect(() => {
-    const element = scrollRef.current;
-    if (!element) return;
-
-    element.addEventListener("scroll", handleScroll, { passive: true });
-    return () => element.removeEventListener("scroll", handleScroll);
-  }, [handleScroll]);
-
-  useEffect(() => {
-    const scrollElement = scrollRef.current;
-    if (!scrollElement) return;
-
-    const currentHeight = scrollElement.scrollHeight;
-    const hasNewContent = currentHeight !== lastContentHeight.current;
-
-    if (hasNewContent) {
-      if (scrollState.autoScrollEnabled) {
-        requestAnimationFrame(() => {
-          scrollToBottom(lastContentHeight.current === 0);
-        });
-      }
-      lastContentHeight.current = currentHeight;
-    }
-  }, [content, scrollState.autoScrollEnabled, scrollToBottom]);
-
-  useEffect(() => {
-    const element = scrollRef.current;
-    if (!element) return;
-
-    const resizeObserver = new ResizeObserver(() => {
-      if (scrollState.autoScrollEnabled) {
-        scrollToBottom(true);
-      }
-    });
-
-    resizeObserver.observe(element);
-    return () => resizeObserver.disconnect();
-  }, [scrollState.autoScrollEnabled, scrollToBottom]);
-
-  const disableAutoScroll = useCallback(() => {
-    const atBottom = scrollRef.current
-      ? checkIsAtBottom(scrollRef.current)
-      : false;
-
-    // Only disable if not at bottom
-    if (!atBottom) {
-      userHasScrolled.current = true;
-      setScrollState((prev) => ({
-        ...prev,
-        autoScrollEnabled: false,
-      }));
-    }
-  }, [checkIsAtBottom]);
-
-  return {
-    scrollRef,
-    isAtBottom: scrollState.isAtBottom,
-    autoScrollEnabled: scrollState.autoScrollEnabled,
-    scrollToBottom: () => scrollToBottom(false),
-    disableAutoScroll,
-  };
-}

src/features/problems/bot/components/form.tsx

@@ -12,7 +12,6 @@ import { useTranslations } from "next-intl";
 import MdxPreview from "@/components/mdx-preview";
 import { Textarea } from "@/components/ui/textarea";
 import { BotIcon, SendHorizonal } from "lucide-react";
-import { ScrollArea } from "@/components/ui/scroll-area";
 import { PreDetail } from "@/components/content/pre-detail";
 import { TooltipButton } from "@/components/tooltip-button";
 import { useProblemEditorStore } from "@/stores/problem-editor";
@@ -100,7 +99,6 @@ export const BotForm = ({
       ) ? (
         <div className="relative flex-1">
           <div className="absolute h-full w-full">
-            <ScrollArea className="h-full [&>[data-radix-scroll-area-viewport]>div:min-w-0 [&>[data-radix-scroll-area-viewport]>div]:!block">
             <ChatMessageList>
               {messages
                 .filter(
@@ -142,7 +140,6 @@ export const BotForm = ({
                   );
                 })}
             </ChatMessageList>
-            </ScrollArea>
           </div>
         </div>
       ) : (