require('dotenv-flow').config();

const express = require('express');
const session = require("express-session");

const cors = require('cors');
const cookieParser = require('cookie-parser');
const helmet = require("helmet");

const redis = require('redis');
const RedisStore = require("connect-redis").default;
const neo4j = require('neo4j-driver');

const logger = require("./utils/logger")(module);

const app = express();

// Enable this if you run behind a proxy (e.g. nginx)
app.set('trust proxy', process.env.TRUST_PROXY);

// Configure Redis client and connect
const redisClient = redis.createClient({
	host: process.env.REDIS_HOST,
	port: process.env.REDIS_PORT,
});

redisClient.connect()
	.then(() => {
		logger.info("Connected to Redis store");
	})
	.catch((error) => {
		logger.error("Redis connection error", { error });
		cleanupFunc();
	});

const redisStore = new RedisStore({ client: redisClient });

// Configure Neo4j driver and connect
const neo4jDriver = neo4j.driver(
	process.env.NEO4J_URL,
	neo4j.auth.basic(process.env.NEO4J_USER, process.env.NEO4J_PASSWD)
);
const neo4jSession = neo4jDriver.session();

(async () => {
	try {
		await neo4jSession.run('MATCH () RETURN 1 LIMIT 1');
		logger.info("Connected to Neo4j graph DB");
	} catch (error) {
		logger.error("Neo4j connection error", { error });
		cleanupFunc();
	}
})();

// Configure session middleware
app.use(session({
	store: redisStore,
	secret: process.env.SESSION_SECRET,
	resave: false,
	saveUninitialized: false,
	cookie: {
		secure: 'auto', // if true only transmit cookie over https
		httpOnly: true, // if true prevent client side JS from reading the cookie 
	}
}));

// Configure CORS options
const corsOptions = {
	origin: [process.env.CORS_ORIGIN],
}

app.use(cors(corsOptions));
app.use(cookieParser());

// Configure helmet
app.use(helmet());
app.disable('x-powered-by')

app.use(express.json());
app.use(express.urlencoded({ extended: true }));

// Static
app.use(express.static(__dirname + '/static'));

// Routes
app.use("/api/auth/", require("./routes/auth"));
app.use("/api/playlists", require("./routes/playlists"));

// Fallbacks
app.use((_req, res) => {
	return res.status(404).send(
		"Guess the <a href=\"https://github.com/20kaushik02/spotify-manager\">cat's</a> out of the bag!"
	);
});

const port = process.env.PORT || 3000;

const server = app.listen(port, () => {
	logger.info(`App Listening on port ${port}`);
});

const cleanupFunc = async () => {
	logger.debug('SIGTERM signal received: closing server');
	if (neo4jSession) await neo4jSession.close();
	if (neo4jDriver) await neo4jDriver.close();
	logger.debug('Neo4j connection closed');
	if (redisClient) await redisClient.disconnect();
	logger.debug('Redis client disconnected');
	server.close(() => {
		logger.debug('HTTP server closed');
	});
}

process.on('SIGTERM', cleanupFunc);