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// File llama.ts
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import { ChatOllama } from "@langchain/ollama";
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const llama = new ChatOllama({
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  model: "llama3.2:latest",
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});
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export default llama;
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// File route.ts
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import llama from "@/models/llama";
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import { AIMessage, HumanMessage } from "@langchain/core/messages";
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import { tool } from "@langchain/core/tools";
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import { LangChainAdapter, type Message } from "ai";
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import { NextResponse } from "next/server";
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import { z } from "zod";
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export async function POST(req: Request) {
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  const { messages } = await req.json();
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  try {
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    const response = await llama
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      .bindTools([
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        tool(
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          async (input) => {
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            console.log(input);
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            return input.a * input.b;
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          },
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          {
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            name: "multiply",
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            description: "Multiplies a and b.",
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            schema: z.object({
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              a: z.number(),
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              b: z.number(),
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            }),
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          }
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        ),
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      ])
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      .stream(
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        messages.map((message: Message) =>
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          message.role == "user"
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            ? new HumanMessage(message.content)
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            : new AIMessage(message.content)
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        )
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      );
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    return LangChainAdapter.toDataStreamResponse(response);
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  } catch (error: any) {
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    console.log(error);
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    return NextResponse.json({ error: error.message }, { status: 500 });
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  }
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}
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// useChat function
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const { handleSubmit, input, handleInputChange, messages } = useChat({
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    api: "/api/bot",
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    onError(error) {
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      console.log(error);
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    },
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    onResponse(response) {
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      console.log(response);
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    },
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    onFinish(message, options) {
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      console.log(message);
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    },
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  });