/**

* This is the main entry point for the application, a simple server that

* runs some checks, and then serves up the app from the ./dist directory

* Also imports some routes for status checks/ ping and config saving

* Note: The app must first be built (yarn build) before this script is run

* */

/* Import built-in Node server modules */

const http = require('http');

const path = require('path');

const util = require('util');

const dns = require('dns');

const os = require('os');

/* Import Express + middleware functions */

const express = require('express');

const history = require('connect-history-api-fallback');

/* Kick of some basic checks */

require('./services/update-checker'); // Checks if there are any updates available, prints message

require('./services/config-validator'); // Include and kicks off the config file validation script

/* Include route handlers for API endpoints */

const statusCheck = require('./services/status-check'); // Used by the status check feature, uses GET

const saveConfig = require('./services/save-config'); // Saves users new conf.yml to file-system

const rebuild = require('./services/rebuild-app'); // A script to programmatically trigger a build

const systemInfo = require('./services/system-info'); // Basic system info, for resource widget

const sslServer = require('./services/ssl-server'); // TLS-enabled web server

const corsProxy = require('./services/cors-proxy'); // Enables API requests to CORS-blocked services

/* Helper functions, and default config */

const printMessage = require('./services/print-message'); // Function to print welcome msg on start

const ENDPOINTS = require('./src/utils/defaults').serviceEndpoints; // API endpoint URL paths

/* Checks if app is running within a container, from env var */

const isDocker = !!process.env.IS_DOCKER;

/* Checks env var for port. If undefined, will use Port 80 for Docker, or 4000 for metal */

const port = process.env.PORT || (isDocker ? 80 : 4000);

/* Attempts to get the users local IP, used as part of welcome message */

const getLocalIp = () => {

const dnsLookup = util.promisify(dns.lookup);

return dnsLookup(os.hostname());

};

/* Gets the users local IP and port, then calls to print welcome message */

const printWelcomeMessage = () => {

};

/* Just console.warns an error */

const printWarning = (msg, error) => {

console.warn(`\x1b[103m\x1b[34m${msg}\x1b[0m\n`, error || ''); // eslint-disable-line no-console

};

/* A middleware function for Connect, that filters requests based on method type */

const method = (m, mw) => (req, res, next) => (req.method === m ? mw(req, res, next) : next());

const app = express()

// Load SSL redirection middleware

.use(sslServer.middleware)

// Serves up static files

.use(express.static(path.join(__dirname, 'dist')))

.use(express.static(path.join(__dirname, 'public')))

// Load middlewares for parsing JSON, and supporting HTML5 history routing

.use(express.json({ limit: '1mb' }))

.use(history())

// GET endpoint to run status of a given URL with GET request

.use(ENDPOINTS.statusCheck, (req, res) => {

try {

statusCheck(req.url, async (results) => {

await res.end(results);

});

} catch (e) {

printWarning(`Error running status check for ${req.url}\n`, e);

}

})

// POST Endpoint used to save config, by writing conf.yml to disk

.use(ENDPOINTS.save, method('POST', (req, res) => {

try {

saveConfig(req.body, (results) => { res.end(results); });

} catch (e) {

printWarning('Error writing config file to disk', e);

res.end(JSON.stringify({ success: false, message: e }));

}

}))

// GET endpoint to trigger a build, and respond with success status and output

.use(ENDPOINTS.rebuild, (req, res) => {

rebuild().then((response) => {

res.end(JSON.stringify(response));

}).catch((response) => {

res.end(JSON.stringify(response));

});

})

// GET endpoint to return system info, for widget

.use(ENDPOINTS.systemInfo, (req, res) => {

try {

const results = systemInfo();

systemInfo.success = true;

res.end(JSON.stringify(results));

} catch (e) {

res.end(JSON.stringify({ success: false, message: e }));

}

})

// GET for accessing non-CORS API services

.use(ENDPOINTS.corsProxy, (req, res) => {

try {

corsProxy(req, res);

} catch (e) {

res.end(JSON.stringify({ success: false, message: e }));

}

});

/* Create HTTP server from app on port, and print welcome message */

http.createServer(app)

.listen(port, () => {

printWelcomeMessage();

})

.on('error', (err) => {

printWarning('Unable to start Dashy\'s Node server', err);

});

/* Check, and if possible start SSL server too */

sslServer.startSSLServer(app);