/**
 * Config route handler
 * Handles configuration get/update and client-side config
 */

const fs = require('fs');
const path = require('path');

/**
 * Handle GET /api/config endpoint
 * @param {http.IncomingMessage} req - HTTP request object
 * @param {http.ServerResponse} res - HTTP response object
 * @param {Object} config - Application configuration
 */
function handleGetConfig(req, res, config) {
  res.writeHead(200, { 'Content-Type': 'application/json' });
  res.end(JSON.stringify(config));
}

/**
 * Handle POST /api/config/update endpoint
 * @param {http.IncomingMessage} req - HTTP request object
 * @param {http.ServerResponse} res - HTTP response object
 * @param {Object} config - Application configuration (will be modified)
 */
function handleUpdateConfig(req, res, config) {
  let body = '';
  req.on('data', chunk => {
    body += chunk.toString();
  });
  
  req.on('end', () => {
    try {
      const newConfig = JSON.parse(body);
      if (newConfig.sites) {
        // Update config object (passed by reference)
        Object.assign(config, newConfig);
        
        // Save to file
        const configPath = path.join('config', 'sites.json');
        fs.writeFileSync(configPath, JSON.stringify(config, null, 2));
        
        res.writeHead(200, { 'Content-Type': 'application/json' });
        res.end(JSON.stringify({ success: true, message: 'Configuration updated' }));
      } else {
        throw new Error('Invalid configuration format');
      }
    } catch (error) {
      console.error('Error updating configuration:', error);
      res.writeHead(400, { 'Content-Type': 'application/json' });
      res.end(JSON.stringify({ error: error.message }));
    }
  });
}

/**
 * Handle GET /api/config/client endpoint
 * Returns client-side configuration (API keys, default location)
 * @param {http.IncomingMessage} req - HTTP request object
 * @param {http.ServerResponse} res - HTTP response object
 */
function handleClientConfig(req, res) {
  res.writeHead(200, { 'Content-Type': 'application/json' });
  res.end(JSON.stringify({
    openweathermapApiKey: process.env.OPENWEATHERMAP_API_KEY || '',
    defaultLocation: {
      latitude: parseFloat(process.env.DEFAULT_LATITUDE) || 59.3293,
      longitude: parseFloat(process.env.DEFAULT_LONGITUDE) || 18.0686,
      name: process.env.DEFAULT_LOCATION_NAME || 'Stockholm'
    }
  }));
}

module.exports = {
  handleGetConfig,
  handleUpdateConfig,
  handleClientConfig
};