/* Retrieval-Augmented Generation */

import { ChatOpenAI } from "langchain/chat_models/openai";
import { OpenAIEmbeddings } from "langchain/embeddings/openai";
import { PromptTemplate } from "langchain/prompts";
import {
  RunnableSequence,
  RunnablePassthrough,
} from "langchain/schema/runnable";
import { MemoryVectorStore } from "langchain/vectorstores/memory";
import { StringOutputParser } from "langchain/schema/output_parser";

const model = new ChatOpenAI({});

const vectorStore = await MemoryVectorStore.fromTexts(
  [
    "mitochondria is the powerhouse of the cell",
    "lysosomes are the garbage disposal of the cell",
    "the nucleus is the control center of the cell",
  ],
  [{ id: 1 }, { id: 2 }, { id: 3 }],
  new OpenAIEmbeddings(),
);

const prompt =
  PromptTemplate.fromTemplate(`Answer the question based only on the following context:
{context}

Question: {question}`);

const chain = RunnableSequence.from([
  prompt,
  model,
  new StringOutputParser(),
]);

const result = await chain.invoke("What is the powerhouse of the cell?");

console.log(result);