feat(webui): add initial webui with websocket chat flow

2026-04-18 18:51:53 +00:00
parent 6bfb75ed03
commit 9ed3031a42
76 changed files with 7088 additions and 38 deletions
@@ -0,0 +1,109 @@
+import { useCallback, useEffect, useRef, useState } from "react";
+import { ArrowDown } from "lucide-react";
+
+import { MessageBubble } from "@/components/MessageBubble";
+import { Button } from "@/components/ui/button";
+import { cn } from "@/lib/utils";
+import type { UIMessage } from "@/lib/types";
+
+interface MessageListProps {
+  messages: UIMessage[];
+  isStreaming: boolean;
+}
+
+const NEAR_BOTTOM_PX = 48;
+
+/**
+ * Scrollable message log. Auto-sticks to the bottom as new content arrives,
+ * but only when the user was already at the bottom — preserving scroll
+ * position when they've scrolled up to read earlier turns. A floating
+ * "scroll to bottom" button appears whenever we're detached from the bottom.
+ */
+export function MessageList({ messages, isStreaming }: MessageListProps) {
+  const scrollRef = useRef<HTMLDivElement>(null);
+  const [atBottom, setAtBottom] = useState(true);
+
+  const scrollToBottom = useCallback((smooth = false) => {
+    const el = scrollRef.current;
+    if (!el) return;
+    el.scrollTo({
+      top: el.scrollHeight,
+      behavior: smooth ? "smooth" : "auto",
+    });
+  }, []);
+
+  // Keep the viewport pinned to the bottom as long as the user hasn't
+  // scrolled up. During streaming we do instant jumps (smooth scrolling each
+  // token fights the incoming animations); on settled updates we animate.
+  useEffect(() => {
+    if (!atBottom) return;
+    scrollToBottom(!isStreaming);
+  }, [messages, isStreaming, atBottom, scrollToBottom]);
+
+  useEffect(() => {
+    const el = scrollRef.current;
+    if (!el) return;
+    const onScroll = () => {
+      const distance = el.scrollHeight - el.scrollTop - el.clientHeight;
+      setAtBottom(distance < NEAR_BOTTOM_PX);
+    };
+    el.addEventListener("scroll", onScroll, { passive: true });
+    return () => el.removeEventListener("scroll", onScroll);
+  }, []);
+
+  if (messages.length === 0) {
+    return (
+      <div className="flex h-full items-center justify-center text-sm text-muted-foreground">
+        Say hi to get started.
+      </div>
+    );
+  }
+
+  return (
+    <div className="relative flex min-h-0 flex-1 overflow-hidden">
+      <div
+        ref={scrollRef}
+        className={cn(
+          "h-full overflow-y-auto scroll-smooth",
+          "[&::-webkit-scrollbar]:w-1.5",
+          "[&::-webkit-scrollbar-thumb]:rounded-full",
+          "[&::-webkit-scrollbar-thumb]:bg-muted-foreground/30",
+          "[&::-webkit-scrollbar-track]:bg-transparent",
+        )}
+      >
+        <div className="mx-auto flex w-full max-w-[64rem] flex-col gap-6 px-4 pt-4 pb-8">
+          {messages.map((m) => (
+            <MessageBubble key={m.id} message={m} />
+          ))}
+        </div>
+      </div>
+
+      {/* Top fade so messages slide under the header gracefully. */}
+      <div
+        aria-hidden
+        className="pointer-events-none absolute inset-x-0 top-0 h-6 bg-gradient-to-b from-background to-transparent"
+      />
+      {/* Bottom fade so messages fade out behind the composer. */}
+      <div
+        aria-hidden
+        className="pointer-events-none absolute inset-x-0 bottom-0 h-8 bg-gradient-to-t from-background to-transparent"
+      />
+
+      {!atBottom && (
+        <Button
+          variant="outline"
+          size="icon"
+          onClick={() => scrollToBottom(true)}
+          className={cn(
+            "absolute bottom-2 left-1/2 h-8 w-8 -translate-x-1/2 rounded-full shadow-md",
+            "bg-background/90 backdrop-blur",
+            "animate-in fade-in-0 zoom-in-95",
+          )}
+          aria-label="Scroll to bottom"
+        >
+          <ArrowDown className="h-4 w-4" />
+        </Button>
+      )}
+    </div>
+  );
+}