API/app.ts

import express from 'express';
import * as http from 'http';
import * as dotenv from 'dotenv';
import swaggerUi from 'swagger-ui-express';
import swaggerJSDoc from 'swagger-jsdoc';
import logger from './src/middleware/logger';

// Router imports
import {calendarRouter} from './src/models/calendar/Calendar.router';
import {feedbackRouter} from './src/models/feedback/Feedback.router';


let cors = require('cors');

dotenv.config();

if (!process.env.PORT) {
	logger.error('No port');
	process.exit(1);
}

const port: number = parseInt(process.env.PORT, 10);

const app: express.Application = express();
const server: http.Server = http.createServer(app);

// Behind Plesk's nginx, req.ip is the proxy unless we trust the forwarded header.
// Verify the resolved client IP is correct in staging before relying on it
// (used by the feedback rate limiter).
app.set('trust proxy', 1);

// here we are adding middleware to parse all incoming requests as JSON
app.use(express.json());

// Configure CORS
let allowedHosts = [
	'https://www.nachklang.art',
	'https://calendar.nachklang.art',
	'https://feedback.nachklang.art'
];
const isDev = process.env.NODE_ENV !== 'production';
const localhostRegex = /^http:\/\/localhost:\d+$/;
// Matches http://<private-LAN-IPv4>:<port> - needed so the feedback form can
// be reached from a real phone over WiFi during dev (the phone's Origin is
// the dev machine's LAN IP, never "localhost"). Dev-only, same as above.
const lanIpRegex = /^http:\/\/(192\.168\.\d{1,3}\.\d{1,3}|10\.\d{1,3}\.\d{1,3}\.\d{1,3}|172\.(1[6-9]|2\d|3[01])\.\d{1,3}\.\d{1,3}):\d+$/;
app.use(cors({
	allowedHeaders: ['Content-Type', 'X-Session-Id', 'X-Session-Key'],
	origin: function (origin: any, callback: any) {
		// Allow requests with no origin
		if (!origin) return callback(null, true);

		// Any localhost port, or a private-LAN IP, is fine outside production -
		// dev servers pick whatever port is free (Next.js falls back from 3000
		// if it's taken), and real-device testing hits the dev machine by IP.
		if (isDev && (localhostRegex.test(origin) || lanIpRegex.test(origin))) {
			return callback(null, true);
		}

		// Block requests with wrong origin
		if (allowedHosts.indexOf(origin) === -1) {
			return callback(new Error('The CORS policy doesn\'t allow access for your origin.'), false);
		}

		// Allow all other requests
		return callback(null, true);
	}
}));

// Swagger documentation
const swaggerDefinition = {
	openapi: '3.0.0',
	info: {
		title: 'Nachklang e.V. REST API',
		version: '0.1.0',
		license: {
			name: 'Licensed Under MIT',
			url: 'https://spdx.org/licenses/MIT.html'
		},
		contact: {
			name: 'Nachklang e.V.',
			url: 'https://www.nachklang.art'
		}
	}
};

const options = {
	swaggerDefinition,
	// Paths to files containing OpenAPI definitions
	apis: [
		'./src/models/**/*.interface.ts',
		'./src/models/**/*.router.ts'
	]
};

const swaggerSpec = swaggerJSDoc(options);

app.use(
	'/docs',
	swaggerUi.serve,
	swaggerUi.setup(swaggerSpec)
);

// Add routers
app.use('/calendar', calendarRouter);
app.use('/feedback', feedbackRouter);

// this is a simple route to make sure everything is working properly
app.get('/', (req: express.Request, res: express.Response) => {
	res.status(200).send('Welcome to the Nachklang e.V. REST API!');
});

server.listen(port, () => {
	logger.info('Server listening on Port ' + port);
});