import { NextResponse } from "next/server";
import path from "path";
import fs from "fs";
import csv from "csv-parser";

type User = {
  name: string;
  email: string;
  password: string;
}

/**
 * @returns {array} - Array of Objects containing user data
 */
async function readUserCsv(): Promise<User[]>{
  return new Promise((resolve, reject) => {
  // Dynamic csv location generation
  let csvPath = path.dirname(__dirname); // /login
  csvPath = path.dirname(csvPath); // /api
  csvPath = path.dirname(csvPath); // /app
  csvPath = path.dirname(csvPath); // /src
  csvPath = path.dirname(csvPath); // /[project] // ? not sure why this dirfolder is here...
  csvPath = path.dirname(csvPath); // /termor-tracker
  csvPath = path.join(csvPath,"src","databases","Users.csv");
  //Forms array for user data
  let results : User[] = [];

  //Reads data and adds it to results
  fs.createReadStream(csvPath)
    .pipe(csv())
    .on("data", (data) => results.push(data))
    .on("end", () => {
      resolve(results)
    })
    .on("error", (error) => {
      reject(error)
    })

  });
}

function findUserByEmail(users: User[], email: string): User | undefined {
  return users.find((user) => user.email === email);
}

export async function POST(request: Request) {
  try {
    const body = await request.json(); // Parse incoming JSON data
    const {email, password } = body;
    console.log("Login API received data");

    const userData = await readUserCsv();

    console.log(userData)
    console.log("Email:", email); // ! remove
    console.log("Password:", password);// ! remove

    const foundUser = findUserByEmail(userData,email)
    if (foundUser && foundUser.password === password) {
      console.log("User Details Correct")
      return NextResponse.json({ message: "Login successful!" }, { status: 200 });
    } else {
      console.log("User email or password is invalid")
      return NextResponse.json({ message: "Email and/or password are invalid" }, { status: 401 });
    }


  } catch (error) {
    console.error("Error in signup endpoint:", error);
    return NextResponse.json({ message: "Internal Server Error" }, { status: 500 });
  }
}