const WebSocket = require('ws');
const UrlParser = require('url');
const uuid = require('node-uuid');
const Messenger = require('./messenger');

const RicochetApp = require(`${__dirname}/../server/ricochet.js`);

const apps = {
    '/ricochet': new RicochetApp({ messenger: new Messenger() })
};

// Make sure all apps follow the messaging contract.
Object.keys(apps).forEach((key) => {
    const app = apps[key];
    
    const valid = app && app.messenger && app.onConnect && app.onMessage && app.onDisconnect;

    if (!valid) {
        delete apps[key];
        console.log(`==================== \n\nCRITICAL ERROR! \n\nApplication at ${key} is missing one or more: messenger, onConnect, onMessage, onDisconnect.\n\n====================\n`);
    }
});

const onConnect = (ws, req) => {
    // Store an ID on the socket connection.
    ws.id = uuid.v4();
    
    const url = UrlParser.parse(req.url, true);
    const app = apps[url.pathname];
    
    if (app) {
        app.messenger.subscribe(ws);

        app.onConnect(ws, req);

        ws.on('message', (rawBody) => {
            app.onMessage(ws, rawBody);
        });

        ws.on('close', () => {
            app.onDisconnect(ws);
            app.messenger.unsubscribe(ws);
        });
    }
};

//===== Generic socket server for any application instantiated above.
const wss = new WebSocket.Server({ port: 8080 });
wss.on('connection', onConnect);

console.log("Websocket server listening on :8080");