const assert = require('assert');
const util = require('util');

const express = require('express');

const PORT = parseInt(process.env.PORT || '8080');
const app = express();
const axios = require('axios');

const {
  MEMBERSHIP_SERVICE_HOST,
} = process.env;

assert.equal(
  typeof MEMBERSHIP_SERVICE_HOST,
  'string',
  `Expexted 'MEMBERSHIP_SERVICE_HOST' to be set. Got: ${util.format(MEMBERSHIP_SERVICE_HOST)}`
);

function getRandomNumber(min, max) {
  return Math.floor(Math.random() * (max - min) + min);
}

app.get('/test', (req, res) => {
  res.send('Coupon service is up and running!');
});

app.get('/coupons', (req, res) => {
  console.log('Coupon request received!');

  // Fetch from membership api
  axios.get(`http://${MEMBERSHIP_SERVICE_HOST}/isMember`)
    .then(function (response) {
      console.log('Got response from membership service!', response.data);
      res.json({
        coupon: getRandomNumber(1, 25),
        isMember: response.data.isMember
      });
    })
    .catch(function (error) {
      console.log(error);
    });
});

app.post('/apply-coupon', (req, res) => {
  console.log('Applying coupon!');

    // Fetch from membership api
    axios.get(`http://${MEMBERSHIP_SERVICE_HOST}/isMember`)
    .then(function (response) {
      console.log('Got response from membership service!', response.data);
      res.json({
        coupon: getRandomNumber(1, 25),
        isMember: response.data.isMember
      });
    })
    .catch(function (error) {
      console.log(error);
    });
});

const server = app.listen(PORT, () => {
  console.log(`Listening for requests on port ${PORT}`);
});

// Add signal handler to gracefully shutdown the server
process.on('SIGTERM', () => {
  console.log('Received SIGTERM. Shutting down server.');
  server.close(() => {
    console.log('Server closed.');
  });
});