import "dotenv/config";
import * as path from "node:path";
import { RAGApplicationBuilder, TextLoader } from "@llm-tools/embedjs";
import { LmdbCache } from "@llm-tools/embedjs/cache/lmdb";
import { MongoDb } from "@llm-tools/embedjs/vectorDb/mongodb";
import * as fs from "fs";

import express from "express";
import cors from "cors";

const app = express();
app.use(express.json());
app.use(cors());

const port = 4000;
app.get("/initLoader", async (req, res) => {
  //From sample file add loaders.
  const llmApplication = await new RAGApplicationBuilder()
    .setCache(new LmdbCache({ path: path.resolve("./cache") }))
    .setVectorDb(
      new MongoDb({
        connectionString:
          "MONGODB_CONNECTION_URI",
      })
    )
    .build();

  const folderPath = "./files";
  // Read all files in the folder
  fs.readdir(folderPath, (err, files) => {
    if (err) {
      return console.error(`Unable to scan directory: ${err}`);
    }

    // Loop through the files
    for (const file of files) {
      const filePath = path.join(folderPath, file);

      // Perform an operation on each file, for example, log file name
      console.log(`Processing file: ${filePath}`);

      // You can read the file contents if needed
      fs.readFile(filePath, "utf8", async (err, data) => {
        if (err) {
          console.error(`Error reading file: ${err}`);
        } else {
          console.log(`File content of ${file}`);
          const fileType = getFileExtension(file);
          switch (fileType) {
            case "txt":
              await llmApplication.addLoader(new TextLoader({ text: data }));
              break;
            case "pdf":
              await llmApplication.addLoader(
                new PdfLoader({
                  filePathOrUrl: path.resolve(filePath),
                })
              );
            default:
              break;
          }
        }
      });
    }
  });

  res.send(200);
});

const getFileExtension = (fileName) => {
  return fileName.split(".").pop(); // Returns the last part after the last '.'
};

app.post("/searchQuery", async (req, res) => {
  const { searchText } = req.body;
  console.log("inside add loader Post call", req.body);
  const llmApplication = await new RAGApplicationBuilder()
    .setCache(new LmdbCache({ path: path.resolve("./cache") }))
    .setVectorDb(
      new MongoDb({
        connectionString:
          "MONGODB_CONNECTION_URI",
      })
    )
    .build();

let result = await llmApplication.query(searchText);
console.log(searchText, " ==> ", result.content);


  res.status(200).json({ result: result.content });
});


app.listen(port, () => {
  console.log(`Example app listening on port ${port}`);
});