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, 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 {
    const { q = '', limit = 20 } = req.query;

    let result;
    if (q.trim()) {
      // Search by name
      result = await sql`
        SELECT id, name, set_name, rarity, card_type, image_url, market_price, game
        FROM cards
        WHERE name ILIKE ${`%${q}%`}
        ORDER BY name
        LIMIT ${parseInt(limit)}
      `;
    } else {
      // Return all cards if no search query
      result = await sql`
        SELECT id, name, set_name, rarity, card_type, image_url, market_price, game
        FROM cards
        ORDER BY name
        LIMIT ${parseInt(limit)}
      `;
    }

    res.status(200).json({
      success: true,
      cards: result.rows,
      pagination: {
        page: 1,
        limit: parseInt(limit),
        total: result.rows.length,
        pages: 1
      },
      filters: {
        games: [...new Set(result.rows.map(card => card.game).filter(Boolean))],
        rarities: [...new Set(result.rows.map(card => card.rarity).filter(Boolean))],
        sets: [...new Set(result.rows.map(card => card.set_name).filter(Boolean))]
      }
    });

  } catch (error) {
    console.error('Error searching cards:', error);
    res.status(500).json({ error: 'Internal server error' });
  }
}