// Debug version of middleware
const fs = require('fs');
const path = require('path');

function createCacheBustingMiddleware(version) {
  return function cacheBustingMiddleware(req, res, next) {
    console.log('[MIDDLEWARE] Request for:', req.path);
    
    const originalSendFile = res.sendFile.bind(res);

    res.sendFile = function(filePath, options, callback) {
      console.log('[MIDDLEWARE] sendFile called with:', filePath);
      console.log('[MIDDLEWARE] File extension check:', path.extname(filePath));
      
      if (filePath && (filePath.endsWith('.html') || filePath.endsWith('.htm'))) {
        console.log('[MIDDLEWARE] Processing HTML file');
        try {
          const data = fs.readFileSync(filePath, 'utf8');
          console.log('[MIDDLEWARE] File read successfully, length:', data.length);
          
          // Simple test: add comment
          const modifiedHtml = data.replace('</head>', '<!-- cache-busted -->\n</head>');
          
          res.setHeader('Content-Type', 'text/html; charset=utf-8');
          res.send(modifiedHtml);
          
          if (callback) callback();
        } catch (err) {
          console.error('[MIDDLEWARE] Error:', err);
          return originalSendFile(filePath, options, callback);
        }
      } else {
        console.log('[MIDDLEWARE] Not an HTML file, using original');
        return originalSendFile(filePath, options, callback);
      }
    };

    next();
  };
}

module.exports = { createCacheBustingMiddleware };