server.js

require('dotenv').config();
const express = require('express');
const bodyParser = require('body-parser');
const { getRates, getSymbols, getHistoricalRate } = require('./lib/fixer-service');
const { convertCurrency } = require('./lib/free-currency-service');

const app = express();
const port = process.env.PORT || 3000;

// Set public folder as root
app.use(express.static('public'));

// Parse POST data as URL encoded data
app.use(bodyParser.urlencoded({
  extended: true,
}));

// Parse POST data as JSON
app.use(bodyParser.json());

// Provide access to node_modules folder
app.use('/scripts', express.static(`${__dirname}/node_modules/`));


const errorHandler = (err, req, res) => {
  if (err.response) {
    // The request was made and the server responded with a status code
    // that falls out of the range of 2xx
    res.status(403).send({ title: 'Server responded with an error', message: err.message });
  } else if (err.request) {
    // The request was made but no response was received
    res.status(503).send({ title: 'Unable to communicate with server', message: err.message });
  } else {
    // Something happened in setting up the request that triggered an Error
    res.status(500).send({ title: 'An unexpected error occurred', message: err.message });
  }
};

// Fetch Latest Currency Rates
app.get('/api/rates', async (req, res) => {
  try {
    const data = await getRates();
    res.setHeader('Content-Type', 'application/json');
    res.send(data);
  } catch (error) {
    errorHandler(error, req, res);
  }
});

// Fetch Symbols
app.get('/api/symbols', async (req, res) => {
  try {
    const data = await getSymbols();
    res.setHeader('Content-Type', 'application/json');
    res.send(data);
  } catch (error) {
    errorHandler(error, req, res);
  }
});

// Convert Currency
app.post('/api/convert', async (req, res) => {
  try {
    const { from, to } = req.body;
    const data = await convertCurrency(from, to);
    res.setHeader('Content-Type', 'application/json');
    res.send(data);
  } catch (error) {
    errorHandler(error, req, res);
  }
});

// Fetch Currency Rates by date
app.post('/api/historical', async (req, res) => {
  try {
    const { date } = req.body;
    const data = await getHistoricalRate(date);
    res.setHeader('Content-Type', 'application/json');
    res.send(data);
  } catch (error) {
    errorHandler(error, req, res);
  }
});

// Redirect all traffic to index.html
app.use((req, res) => res.sendFile(`${__dirname}/public/index.html`));

app.listen(port, () => {
  // eslint-disable-next-line no-console
  console.log('listening on %d', port);
});