server.js

const express = require('express');
const cors = require('cors');
const path = require('path');
const net = require('net');
require('dotenv').config();

const authRoutes = require('./routes/auth');
const dashboardRoutes = require('./routes/dashboard');
const geekFeedRoutes = require('./routes/geek_feed');
const adminRoutes = require('./routes/admin');
const learningRoutes = require('./routes/learning');
const learnRoutes = require('./routes/learn');
const practiceRoutes = require('./routes/practice');
const problemsRoutes = require('./routes/problems');
const contestsRoutes = require('./routes/create_contest');

const db = require('./config/database');

const app = express();

// Function to check if a port is available
function isPortAvailable(port) {
    return new Promise((resolve) => {
        const server = net.createServer();
        
        server.listen(port, () => {
            server.once('close', () => {
                resolve(true);
            });
            server.close();
        });
        
        server.on('error', () => {
            resolve(false);
        });
    });
}

// Function to find available port (only 3000 or 3001)
async function findAvailablePort() {
    const allowedPorts = [3000, 3001];
    
    for (const port of allowedPorts) {
        if (await isPortAvailable(port)) {
            return port;
        }
    }
    
    throw new Error(`Both ports 3000 and 3001 are in use. Please free one of these ports and try again.`);
}

// Middleware
app.use(cors());
app.use(express.json());
app.use(express.urlencoded({ extended: true }));
app.use(express.static(path.join(__dirname, 'public')));

// Routes
const discussionRoutes = require('./routes/discussion');
app.use('/api/auth', authRoutes);
app.use('/api/dashboard', dashboardRoutes);
app.use('/api/geek-feed', geekFeedRoutes);
app.use('/api/admin', adminRoutes);
app.use('/api/learning', learningRoutes);
app.use('/api/learn', learnRoutes);
app.use('/api/practice', practiceRoutes);
app.use('/api/problems', problemsRoutes);
app.use('/api/contests', contestsRoutes);
app.use('/api/discussion', discussionRoutes);
console.log('📌 Contests routes loaded');
console.log('💬 Discussion routes loaded');

// Health check endpoint for Docker
app.get('/health', (req, res) => {
    res.status(200).json({ 
        status: 'OK', 
        timestamp: new Date().toISOString(),
        service: 'BrainJam Arena'
    });
});

// Serve HTML pages
app.get('/', (req, res) => {
    res.sendFile(path.join(__dirname, 'public', 'index.html'));
});

app.get('/login', (req, res) => {
    res.sendFile(path.join(__dirname, 'public', 'login.html'));
});

app.get('/register', (req, res) => {
    res.sendFile(path.join(__dirname, 'public', 'register.html'));
});

app.get('/dashboard', (req, res) => {
    res.sendFile(path.join(__dirname, 'public', 'dashboard.html'));
});

app.get('/learn', (req, res) => {
    res.sendFile(path.join(__dirname, 'public', 'learn.html'));
});

app.get('/geek-feed', (req, res) => {
    res.sendFile(path.join(__dirname, 'public', 'geek-feed.html'));
});

app.get('/admin-dashboard', (req, res) => {
    res.sendFile(path.join(__dirname, 'public', 'admin-dashboard.html'));
});

app.get('/content-management', (req, res) => {
    res.sendFile(path.join(__dirname, 'public', 'content-management.html'));
});

app.get('/create-resource', (req, res) => {
    res.sendFile(path.join(__dirname, 'public', 'create-resource.html'));
});

app.get('/test-learning-api', (req, res) => {
    res.sendFile(path.join(__dirname, 'public', 'test-learning-api.html'));
});
app.get('/practice', (req, res) => {
    res.sendFile(path.join(__dirname, 'public', 'practice.html'));
});

app.get('/problem-detail', (req, res) => {
    res.sendFile(path.join(__dirname, 'public', 'problem-detail.html'));
});

app.get('/problem-management', (req, res) => {
    res.sendFile(path.join(__dirname, 'public', 'problem-management.html'));
});

// Example for your admin create page:
app.get('/admin-create-contest', (req, res) => {
  res.sendFile(path.join(__dirname, 'public', 'admin-create-contest.html'));
});

app.get('/admin-contest-management', (req, res) => {
  res.sendFile(path.join(__dirname, 'public', 'admin-contest-management.html'));
});

// Error handling middleware
app.use((err, req, res, next) => {
    res.status(500).json({ success: false, error: 'Something went wrong!' });
});

// 404 handler
app.use((req, res) => {
    res.status(404).json({ success: false, error: 'Route not found' });
});

// Start server with automatic port detection (3000 or 3001 only)
async function startServer() {
    try {
        // First try the PORT from environment variable if it's 3000 or 3001
        const preferredPort = process.env.PORT ? parseInt(process.env.PORT) : null;
        
        let PORT;
        if (preferredPort && (preferredPort === 3000 || preferredPort === 3001)) {
            // If PORT is specified and is 3000 or 3001, check if it's available
            if (await isPortAvailable(preferredPort)) {
                PORT = preferredPort;
            } else {
                // Try the other port (if preferred is 3000, try 3001, and vice versa)
                const alternativePort = preferredPort === 3000 ? 3001 : 3000;
                if (await isPortAvailable(alternativePort)) {
                    PORT = alternativePort;
                } else {
                    throw new Error(`Both ports 3000 and 3001 are in use. Please free one of these ports and try again.`);
                }
            }
        } else {
            // No specific port set or invalid port, find available port from 3000/3001
            if (preferredPort && preferredPort !== 3000 && preferredPort !== 3001) {
                // Port not allowed
            }
            PORT = await findAvailablePort();
        }
        
        app.listen(PORT, () => {
            console.log(`🚀 BrainJam Arena server running on http://localhost:${PORT}`);
            console.log(`🌐 Access your application at: http://localhost:${PORT}`);
        });
        
    } catch (error) {
        process.exit(1);
    }
}

// Start the server
startServer();