v4.0: Add web /api/chat route for RAG chatbot

web/app/api/chat/route.ts

@@ -0,0 +1,37 @@
+import { NextRequest, NextResponse } from "next/server";
+
+const API_URL = process.env.CLAUSEGUARD_API_URL || "https://gaurv007-clauseguard-api.hf.space";
+
+export async function POST(req: NextRequest) {
+  try {
+    const body = await req.json();
+    const { message, session_id, history } = body;
+
+    if (!message || !session_id) {
+      return NextResponse.json(
+        { error: "message and session_id are required" },
+        { status: 400 }
+      );
+    }
+
+    const response = await fetch(`${API_URL}/api/chat`, {
+      method: "POST",
+      headers: { "Content-Type": "application/json" },
+      body: JSON.stringify({ message, session_id, history: history || [] }),
+    });
+
+    if (!response.ok) {
+      const err = await response.text().catch(() => "");
+      throw new Error(err || `Backend error: ${response.status}`);
+    }
+
+    const result = await response.json();
+    return NextResponse.json(result);
+  } catch (error: any) {
+    console.error("Chat error:", error.message);
+    return NextResponse.json(
+      { error: error.message || "Chat failed. Try again." },
+      { status: 500 }
+    );
+  }
+}