/* eslint-disable @typescript-eslint/no-var-requires */
const http = require("http");
const crypto = require('crypto');
const log = require('electron-log');
const Config = require('electron-config');
const config = new Config();

let server;
let window;

function initialize(win, callback) {
  window = win;
  server = http.createServer(async function (req, res) {
    let body = "";

    req.on("data", (chunk) => {
      body += chunk.toString(); // convert Buffer to string
    });
    req.on("end", () => {
      const providedToken = req.headers?.authorization?.replace('Bearer ', '') ?? '';
      const isValid = providedToken === getAuthenticationToken();
      if (isValid) {
        log.log('Valid authentication token');
      } else {
        log.log('Invalid authentication token');
        res.writeHead(401);
        res.write('Invalid authentication token');
        res.end();
        return;
      }

      let data;
      try {
        data = JSON.parse(body);
      } catch (error) {
        log.warn(`Invalid body data`);
        res.writeHead(400);
        res.write('Invalid body data');
        res.end();
        return;
      }

      if (data) {
        window.webContents.executeJavaScript(`document.saveFile("${data.filename}", "${data.code}")`).then((result) => {
          res.write(result);
          res.end();
        });
      }
    });
  });

  const autostart = config.get('autostart', false);
  if (autostart) {
    return enable(callback);
  }

  if (callback) return callback();
  return Promise.resolve();
}


function enable(callback) {
  if (isListening()) {
    log.warn('API server already listening');
    return;
  }

  const port = config.get('port', 9990);
  log.log(`Starting http server on port ${port}`);
  return server.listen(port, "127.0.0.1", callback);
}

function disable() {
  if (!isListening()) {
    log.warn('API server not listening');
    return;
  }

  log.log('Stopping http server');
  return server.close();
}

function toggleServer() {
  if (isListening()) {
    return disable();
  } else {
    return enable();
  }
}

function isListening() {
  return server?.listening ?? false;
}

function toggleAutostart() {
  const newValue = !isAutostart();
  config.set('autostart', newValue);
  log.log(`New autostart value is '${newValue}'`);
}

function isAutostart() {
  return config.get('autostart');
}

function getAuthenticationToken() {
  const token = config.get('token');
  if (token) return token;

  const newToken = generateToken();
  config.set('token', newToken);
  return newToken;
}

function generateToken() {
  const buffer = crypto.randomBytes(48);
  return buffer.toString('base64')
}

module.exports = {
  initialize,
  enable, disable, toggleServer,
  toggleAutostart, isAutostart,
  getAuthenticationToken, isListening,
}