server.js

const express = require('express');
const cors = require('cors');
const helmet = require('helmet');
const morgan = require('morgan');
const path = require('path');

// Import routes
const fieldRoutes = require('./routes/fields');
const comparisonRoutes = require('./routes/comparisons');

const app = express();
const PORT = process.env.PORT || 3000;

// Middleware
app.use(helmet());
app.use(cors());
app.use(morgan('combined'));
app.use(express.json());
app.use(express.static(path.join(__dirname, 'public')));

// Routes
app.use('/api/fields', fieldRoutes);
app.use('/api/comparisons', comparisonRoutes);

// Health check endpoint
app.get('/health', (req, res) => {
  res.json({
    status: 'OK',
    message: 'CIA Factbook API is running',
    timestamp: new Date().toISOString()
  });
});

// Root endpoint with API documentation
app.get('/', (req, res) => {
  res.json({
    message: 'CIA World Factbook API',
    version: '1.0.0',
    endpoints: {
      fields: '/api/fields',
      comparisons: '/api/comparisons',
      health: '/health'
    },
    availableFields: [
      'diplomatic-representation-us',
      'economic-overview',
      'gdp-purchasing-power',
      'electricity-access',
      'civil-aircraft-code',
      'military-and-security-forces',
      'climate',
      'urbanization',
      'major-urban-areas-population',
      'drinking-water-source',
      'sanitation-facility-access',
      'education-expenditure',
      'environmental-issues'
    ],
    availableComparisons: [
      'subscriptions-comparison',
      'electricity-country-comparison',
      'energy-country-comparison',
      'airports-country-comparison'
    ]
  });
});

// Error handling middleware
app.use((err, req, res, next) => {
  console.error(err.stack);
  res.status(500).json({
    success: false,
    error: 'Internal server error',
    timestamp: new Date().toISOString()
  });
});

// 404 handler
app.use((req, res) => {
  res.status(404).json({
    success: false,
    error: 'Endpoint not found',
    message: 'Please check the API documentation for available endpoints',
    availableEndpoints: {
      root: '/',
      health: '/health',
      fields: '/api/fields',
      comparisons: '/api/comparisons'
    },
    timestamp: new Date().toISOString()
  });
});

app.listen(PORT, () => {
  console.log(`🚀 CIA Factbook API server running on port ${PORT}`);
  console.log(`📊 API documentation available at http://localhost:${PORT}`);
});