// apps/web/server.js
import express from 'express';
import http from 'http';
import next from 'next';
import { WebSocketServer } from 'ws';
import { applyWSSHandler } from '@trpc/server/adapters/ws';
import { appRouter } from '@lifetracker/trpc/routers/_app';
import { createWSContext } from '@/server/api/ws';
import { parse } from 'url';
import { NextRequestHint } from 'next/dist/server/web/adapter';

const dev = process.env.NODE_ENV !== 'production';

// Create an Express app and HTTP server.
const app = express();
const server = http.createServer(app);

const nextApp = next({
    dev,
    customServer: true,
    hostname: process.env.HOSTNAME || "localhost",
    port: Number(process.env.PORT) || 3000,
});
const handle = nextApp.getRequestHandler();

nextApp.prepare().then(() => {

    // Fallback to NextJS request handling for everything else.
    app.all('*', (req: express.Request, res: express.Response) => {
        return handle(req, res);
    });

    // Create a WebSocket server that shares the same HTTP server.
    const wss = new WebSocketServer({
        noServer: true,
        path: '/api/ws',
    });

    // Attach the TRPC WebSocket handler.
    const handler = applyWSSHandler({
        wss,
        router: appRouter,
        createContext: createWSContext,
    });

    wss.on('connection', (ws) => {
        console.log(`➕➕ Got new websocket connection (now ${wss.clients.size})`);
        ws.once('close', () => {
            console.log(`➖➖ Closed websocket connection (now ${wss.clients.size})`);
        });
    });
    wss.on('error', function (error) {
        console.log(error);
    });

    const port = process.env.PORT || 3000;
    server.listen(port, () => {
        console.log(`> Server listening on http://localhost:${port}`);
        console.log(`> TRPC WebSocket server listening at ws://localhost:${port}/api/ws`);
    });

    app.all('*', (req: express.Request, res: express.Response) => {
        return handle(req, res);
    });

    server.on('upgrade', (request, socket, head) => {
        const { pathname } = parse(request.url!);
        // Only handle WebSocket upgrades of the specific path(s) your application
        // needs to handle
        if (pathname === "/api/ws") {
            wss.handleUpgrade(request, socket, head, function done(ws) {
                console.log("Socket connected");
                // At this point, you have the WebSocket in `ws`
                // and the original HTTP request in `request` available
                ws.send("Hello from Lifetracker!");
            });
        }
    });

    // Handle graceful shutdown.
    process.on('SIGTERM', () => {
        console.log('SIGTERM received, shutting down gracefully.');
        handler.broadcastReconnectNotification();
        server.close();
    });
});