"""
Slide 25: JS-аналог: что есть, чего нет
Section 1: LangChain 1.0
Source: slides/section1-chains/slide-25.js

Сгенерировано автоматически из slide-NN.js / sectionN.pptx.
Паттерн провайдера скопирован из
bro-js/agents/teacher/assistant/src/angry_teacher/llm.py.

Запуск:
  cd langchain-evolution-deck
  cp .env.example .env   # заполни OPENAI_API_KEY
  python examples/slide-025/script.py
"""
import os
from dotenv import load_dotenv
from langchain_openai import ChatOpenAI

load_dotenv()

llm = ChatOpenAI(
    # model="openrouter/free",
    # model="qwen/qwen3.5-35b-a3b",
    model="openai/gpt-oss-20b",
    # model="nvidia/nemotron-3-nano",
    # model="qwen/qwen3.5-9b",
    base_url="https://llm.brojs.ru/v1",
    # base_url="https://api.minimax.io/v1",
    # base_url="http://0.0.0.0:8090/v1",
    # base_url="https://openrouter.ai/api/v1",
    # api_key=os.getenv("MINIMAX_API_KEY"),
    api_key=(os.getenv("OPENAI_API_KEY") or "").strip() or None,
    temperature=0.7,
    stream_usage=True,
)


# === Code from slide 25 ===
import { initChatModel } from "langchain/chat_models/universal";
import { createAgent } from "langchain/agents";
import { tool } from "@langchain/core/tools";
import { z } from "zod";

const getWeather = tool(
  async ({ city }) => `Sunny, 22C in ${city}`,
  { name: "get_weather", description: "Get weather",
    schema: z.object({ city: z.string() }) },
);

const model = await initChatModel("openai:gpt-4.1");
const agent = createAgent({ model, tools: [getWeather] });
const result = await agent.invoke({
  messages: [{ role: "user", content: "weather in Paris?" }],
});