feat: add conversation request-response

frontend/src/components/conversation-bubble.tsx

@@ -0,0 +1,33 @@
+import { cn } from "@/lib/utils";
+import { tw } from "@/utils/tailwind";
+import { cva, type VariantProps } from "class-variance-authority";
+import { LoaderCircleIcon } from "lucide-react";
+
+const bubbleVariants = cva(tw`px-4 py-2 rounded max-w-2/3`, {
+  variants: {
+    type: {
+      question: tw`bg-blue-500 text-gray-200 self-start`,
+      response: tw`bg-neutral-300 text-gray-950 self-end`,
+    },
+    active: {
+      false: tw`grayscale-100 opacity-90`,
+      true: null,
+    },
+  },
+  defaultVariants: {
+    active: true,
+  },
+});
+
+interface Props extends VariantProps<typeof bubbleVariants> {
+  content: string;
+}
+const ConversationBubble = ({ type, active, content }: Readonly<Props>) => {
+  return (
+    <div className={cn(bubbleVariants({ type, active }))}>
+      {content ? content : <LoaderCircleIcon className="animate-spin" />}
+    </div>
+  );
+};
+
+export default ConversationBubble;

frontend/src/routes/conversation.$sessionId.tsx

@@ -4,7 +4,17 @@ import { Input } from "@/components/ui/input";
 import { Separator } from "@/components/ui/separator";
 import { getConversationHistory } from "@/services/get-conversation-history";
 import { createFileRoute, notFound } from "@tanstack/react-router";
-import { SendHorizontalIcon } from "lucide-react";
+import { LoaderCircleIcon, SendHorizontalIcon } from "lucide-react";
+import React, { useEffect, useRef, useState } from "react";
+import { streamingFetch } from "@/utils/streaming-fetch";
+import { env } from "@/env";
+import ConversationBubble from "@/components/conversation-bubble";
+
+interface ConversationData {
+  key: React.Key;
+  content: string;
+  type: "question" | "response";
+}
 
 export const Route = createFileRoute("/conversation/$sessionId")({
   component: RouteComponent,
@@ -18,27 +28,156 @@ export const Route = createFileRoute("/conversation/$sessionId")({
 });
 
 function RouteComponent() {
-  const historyData = Route.useLoaderData();
+  const { history, title } = Route.useLoaderData();
   const { sessionId } = Route.useParams();
+  const [inputValue, setInputValue] = useState("");
+  const [isBusy, setIsBusy] = useState(false);
+  const [conversationPieces, setConversationPieces] = useState<
+    ConversationData[]
+  >([]);
+  const scrollContainer = useRef<HTMLDivElement>(null);
+
+  const scrollToBottom = () => {
+    setTimeout(() => {
+      if (scrollContainer.current) {
+        scrollContainer.current.scrollTo({
+          top: scrollContainer.current.scrollHeight,
+          behavior: "smooth",
+        });
+      }
+    }, 100);
+  };
+
+  // Auto-scroll when conversation pieces change
+  useEffect(() => {
+    scrollToBottom();
+  }, [conversationPieces]);
+
+  const handleSendQuestion = async () => {
+    if (!inputValue || isBusy) {
+      return;
+    }
+    const question = inputValue.trim();
+    setIsBusy(true);
+    setInputValue("");
+
+    setConversationPieces((state) => [
+      ...state,
+      {
+        key: new Date().getTime(),
+        content: question,
+        type: "question",
+      },
+    ]);
+
+    try {
+      setConversationPieces((state) => [
+        ...state,
+        {
+          key: new Date().getTime(),
+          content: "",
+          type: "response",
+        },
+      ]);
+      scrollToBottom();
+
+      let idx = 0;
+      for await (const chunk of streamingFetch(() =>
+        fetch(`${env.VITE_API_URL}/ask-conversation`, {
+          method: "POST",
+          headers: {
+            "Content-Type": "application/json",
+          },
+          body: JSON.stringify({ question, session_id: sessionId }),
+        })
+      )) {
+        setConversationPieces((state) => {
+          const stateCopy = [...state];
+          const lastItem = stateCopy.pop()!;
+          return [
+            ...stateCopy,
+            {
+              key: new Date().getTime(),
+              content: idx++ === 0 ? chunk : lastItem.content + chunk,
+              type: "response",
+            },
+          ];
+        });
+        scrollToBottom();
+      }
+    } catch (err) {
+      console.error("There was an error receiving chunks", err);
+    } finally {
+      setIsBusy(false);
+    }
+  };
 
   return (
-    <div className="flex justify-center p-3 h-full">
+    <div className="flex justify-center p-3 h-screen">
-      <div className="flex flex-col w-xl gap-3">
+      <div className="flex flex-col w-4xl gap-3 h-full max-h-full">
-        <Card className="flex-1 flex flex-col">
+        <Card
-          <CardHeader>
+          className="flex flex-col min-h-0 overflow-hidden"
-            <CardTitle>{historyData.title}</CardTitle>
+          style={{ height: "calc(100vh - 160px)" }}
+        >
+          <CardHeader className="flex-shrink-0">
+            <CardTitle>{title}</CardTitle>
             <Separator orientation="horizontal" />
           </CardHeader>
-          <CardContent className="flex-1 max-h-full">
+          <CardContent className="flex-1 min-h-0 p-4 overflow-hidden">
-            <div className="flex flex-col rounded-sm bg-neutral-50 h-full max-h-full border border-neutral-200 shadow-2xs overflow-y-auto">
+            <div
-              {/* <div className="w-[150px] h-[3500px] bg-amber-400"></div> */}
+              ref={scrollContainer}
+              className="flex flex-col gap-2 rounded-sm bg-neutral-50 h-full border border-neutral-200 shadow-2xs overflow-y-auto p-2"
+            >
+              {history.map((h, idx) => (
+                <React.Fragment key={idx}>
+                  <ConversationBubble
+                    type="question"
+                    active={false}
+                    content={h.question}
+                  />
+                  <ConversationBubble
+                    type="response"
+                    active={false}
+                    content={h.answer}
+                  />
+                </React.Fragment>
+              ))}
+              {!!history.length && (
+                <div className="flex flex-col items-center">
+                  <Separator orientation="horizontal" />
+                  <span className="text-xs text-neutral-400">
+                    End of history
+                  </span>
+                </div>
+              )}
+              {!!conversationPieces.length && (
+                <>
+                  {conversationPieces.map((c) => (
+                    <ConversationBubble
+                      key={c.key}
+                      type={c.type}
+                      content={c.content}
+                    />
+                  ))}
+                </>
+              )}
             </div>
           </CardContent>
         </Card>
-        <div className="flex gap-3">
+        <div className="flex gap-3 flex-shrink-0">
-          <Input className="flex-1" placeholder="Start typing..." />
+          <Input
-          <Button size="icon">
+            className="flex-1"
-            <SendHorizontalIcon />
+            placeholder="Start typing..."
+            value={inputValue}
+            onChange={(e) => setInputValue(e.target.value)}
+            disabled={isBusy}
+          />
+          <Button size="icon" disabled={isBusy} onClick={handleSendQuestion}>
+            {isBusy ? (
+              <LoaderCircleIcon className="animate-spin" />
+            ) : (
+              <SendHorizontalIcon />
+            )}
           </Button>
         </div>
       </div>

frontend/src/utils/streaming-fetch.ts

@@ -0,0 +1,18 @@
+async function* streamingFetch(fetchcall: () => Promise<Response>) {
+  const response = await fetchcall();
+  // Attach Reader
+  if (!response || !response.body) {
+    throw new Error("Empty response");
+  }
+  const reader = response.body.getReader();
+  while (true) {
+    // wait for next encoded chunk
+    const { done, value } = await reader.read();
+    // check if stream is done
+    if (done) break;
+    // Decodes data chunk and yields it
+    yield new TextDecoder().decode(value);
+  }
+}
+
+export { streamingFetch };

frontend/src/utils/tailwind.ts

@@ -0,0 +1,19 @@
+/* A nice to have VScode autocompletion feature 
+
+Make sure you have the Tailwind CSS IntelliSense extension installed in VSCode
+https://marketplace.visualstudio.com/items?itemName=bradlc.vscode-tailwindcss
+
+Open the settings (json) file via CMD + SHIFT + P (macOS) or CTRL + SHIFT + P (Windows)
+Add the below entry to the json file
+{
+  ...
+  "tailwindCSS.experimental.classRegex": ["tw`([^`]*)"],
+}
+
+Allows you to have tailwind auto complete while typing outside of the className attribute
+By using the prefix tw`YOUR_CLASS_NAME_HERE`
+
+Without the extension and settings adjustment, it'll still be interpreted as a string literal (backward compatible)
+*/
+export const tw = (strings: TemplateStringsArray, ...substitution: unknown[]) =>
+  String.raw({ raw: strings }, ...substitution);