require('dotenv').config();
const express = require('express');
const http = require('http');
const { Server } = require("socket.io");
const axios = require('axios');

const app = express();
const server = http.createServer(app);
const io = new Server(server);

app.use(express.static('public'));

// --- Cloudflare Credentials ---
app.get('/api/get-turn-credentials', async (req, res) => {
	try {
		const response = await axios.post(
			`https://rtc.live.cloudflare.com/v1/turn/keys/${process.env.CLOUDFLARE_APP_ID}/credentials/generate-ice-servers`,
			{ ttl: 86400 },
			{ headers: { 'Authorization': `Bearer ${process.env.CLOUDFLARE_API_TOKEN}`, 'Content-Type': 'application/json' } }
		);
		res.json(response.data);
	} catch (error) {
		console.error("Cloudflare error:", error.message);
		res.status(500).json({ error: "Failed to fetch credentials" });
	}
});

// --- Signaling Logic ---
let streamers = {}; // socketId -> { name: "Gaming Stream" }
// Add a map to track relationships: viewerSocketId -> streamerSocketId
let relationships = {};

io.on('connection', (socket) => {
	// 1. Immediately send the list of active streams to the new user
	socket.emit('streamer_list_update', streamers);

	// 2. User wants to go live
	socket.on('start_stream', (name) => {
		streamers[socket.id] = { name: name };
		io.emit('streamer_list_update', streamers); // Notify everyone
	});

	// 3. User wants to watch a specific streamer
	socket.on('join_stream', (streamerId) => {
		relationships[socket.id] = streamerId; // Record the link
		io.to(streamerId).emit('viewer_joined', { viewerId: socket.id });
	});

	// 4. WebRTC Signaling (Offer/Answer/ICE)
	socket.on('webrtc_offer', (data) => {
		io.to(data.target).emit('webrtc_offer', { sdp: data.sdp, sender: socket.id });
	});

	socket.on('webrtc_answer', (data) => {
		io.to(data.target).emit('webrtc_answer', { sdp: data.sdp, sender: socket.id });
	});

	socket.on('ice_candidate', (data) => {
		io.to(data.target).emit('ice_candidate', { candidate: data.candidate, sender: socket.id });
	});

	// 5. Cleanup
	socket.on('disconnect', () => {
		// 1. If a STREAMER left (existing code)
		if (streamers[socket.id]) {
			delete streamers[socket.id];
			io.emit('streamer_list_update', streamers);
		}

		// 2. If a VIEWER left (NEW CODE)
		if (relationships[socket.id]) {
			const streamerId = relationships[socket.id];
			// Tell the specific streamer that this specific viewer is gone
			io.to(streamerId).emit('viewer_left', { viewerId: socket.id });
			delete relationships[socket.id];
		}
	});
});

const PORT = process.env.PORT || 3000;
server.listen(PORT, () => console.log(`Server running on http://localhost:${PORT}`));