feat(lighthouse): Add chat interface (#7878)

Co-authored-by: Chandrapal Badshah <12944530+Chan9390@users.noreply.github.com>

ui/app/api/lighthouse/analyst/route.ts

@@ -0,0 +1,94 @@
+import { LangChainAdapter, Message } from "ai";
+
+import { getLighthouseConfig } from "@/actions/lighthouse/lighthouse";
+import { getCurrentDataSection } from "@/lib/lighthouse/data";
+import {
+  convertLangChainMessageToVercelMessage,
+  convertVercelMessageToLangChainMessage,
+} from "@/lib/lighthouse/utils";
+import { initLighthouseWorkflow } from "@/lib/lighthouse/workflow";
+
+export async function POST(req: Request) {
+  try {
+    const {
+      messages,
+    }: {
+      messages: Message[];
+    } = await req.json();
+
+    if (!messages) {
+      return Response.json({ error: "No messages provided" }, { status: 400 });
+    }
+
+    // Create a new array for processed messages
+    const processedMessages = [...messages];
+
+    // Get AI configuration to access business context
+    const aiConfig = await getLighthouseConfig();
+    const businessContext = aiConfig?.data?.attributes?.business_context;
+
+    // Get current user data
+    const currentData = await getCurrentDataSection();
+
+    // Add context messages at the beginning
+    const contextMessages: Message[] = [];
+
+    // Add business context if available
+    if (businessContext) {
+      contextMessages.push({
+        id: "business-context",
+        role: "assistant",
+        content: `Business Context Information:\n${businessContext}`,
+      });
+    }
+
+    // Add current data if available
+    if (currentData) {
+      contextMessages.push({
+        id: "current-data",
+        role: "assistant",
+        content: currentData,
+      });
+    }
+
+    // Insert all context messages at the beginning
+    processedMessages.unshift(...contextMessages);
+
+    const app = await initLighthouseWorkflow();
+
+    const agentStream = app.streamEvents(
+      {
+        messages: processedMessages
+          .filter(
+            (message: Message) =>
+              message.role === "user" || message.role === "assistant",
+          )
+          .map(convertVercelMessageToLangChainMessage),
+      },
+      {
+        streamMode: ["values", "messages", "custom"],
+        version: "v2",
+      },
+    );
+
+    const stream = new ReadableStream({
+      async start(controller) {
+        for await (const { event, data, tags } of agentStream) {
+          if (event === "on_chat_model_stream") {
+            if (data.chunk.content && !!tags && tags.includes("supervisor")) {
+              const chunk = data.chunk;
+              const aiMessage = convertLangChainMessageToVercelMessage(chunk);
+              controller.enqueue(aiMessage);
+            }
+          }
+        }
+        controller.close();
+      },
+    });
+
+    return LangChainAdapter.toDataStreamResponse(stream);
+  } catch (error) {
+    console.error("Error in POST request:", error);
+    return Response.json({ error: "An error occurred" }, { status: 500 });
+  }
+}