import { sql } from '@vercel/postgres';

export default async function handler(req, res) {
  // Set CORS headers
  res.setHeader('Access-Control-Allow-Origin', '*');
  res.setHeader('Access-Control-Allow-Methods', 'GET, POST, PUT, DELETE, OPTIONS');
  res.setHeader('Access-Control-Allow-Headers', 'Content-Type, Authorization');

  // Handle preflight requests
  if (req.method === 'OPTIONS') {
    res.status(200).end();
    return;
  }

  if (req.method !== 'GET') {
    return res.status(405).json({ error: 'Method not allowed' });
  }

  try {
    // Test database connection
    const result = await sql`SELECT NOW() as current_time, version() as postgres_version`;
    
    return res.status(200).json({
      success: true,
      message: 'PostgreSQL connection successful!',
      data: result.rows[0],
      timestamp: new Date().toISOString()
    });
  } catch (error) {
    console.error('❌ PostgreSQL connection error:', error);
    return res.status(500).json({
      error: 'PostgreSQL connection failed',
      details: error.message,
      stack: error.stack
    });
  }
}