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

export default async function handler(req, res) {
  const { id } = req.query;

  if (req.method === 'GET') {
    try {
      const result = await sql`
        SELECT 
          id, name, set_name, set_code, card_number, rarity, game,
          mana_cost, cmc, card_type, colors, oracle_text,
          power, toughness, image_url, stock_image_url,
          current_price, market_price, scryfall_id, verified,
          quantity
        FROM cards 
        WHERE id = ${id}
      `;

      if (result.rows.length === 0) {
        return res.status(404).json({ error: 'Card not found' });
      }

      const card = result.rows[0];
      
      // Parse colors if it's a JSON string
      if (card.colors && typeof card.colors === 'string') {
        try {
          card.colors = JSON.parse(card.colors);
        } catch (e) {
          card.colors = [];
        }
      }

      res.status(200).json(card);
    } catch (error) {
      console.error('Error fetching card:', error);
      res.status(500).json({ error: 'Failed to fetch card' });
    }
  } else if (req.method === 'PUT') {
    try {
      const {
        name, set_name, set_code, card_number, rarity, game,
        mana_cost, cmc, card_type, colors, oracle_text,
        power, toughness, image_url, stock_image_url,
        current_price, market_price
      } = req.body;

      // Validate required fields
      if (!name || !game) {
        return res.status(400).json({ error: 'Name and game are required fields' });
      }

      // Update the card
      const result = await sql`
        UPDATE cards SET
          name = ${name},
          set_name = ${set_name || null},
          set_code = ${set_code || null},
          card_number = ${card_number || null},
          rarity = ${rarity || null},
          game = ${game},
          mana_cost = ${mana_cost || null},
          cmc = ${cmc || null},
          card_type = ${card_type || null},
          colors = ${JSON.stringify(colors || [])},
          oracle_text = ${oracle_text || null},
          power = ${power || null},
          toughness = ${toughness || null},
          image_url = ${image_url || null},
          stock_image_url = ${stock_image_url || null},
          current_price = ${current_price || null},
          market_price = ${market_price || null},
          updated_at = CURRENT_TIMESTAMP
        WHERE id = ${id}
        RETURNING 
          id, name, set_name, set_code, card_number, rarity, game,
          mana_cost, cmc, card_type, colors, oracle_text,
          power, toughness, image_url, stock_image_url,
          current_price, market_price, scryfall_id, verified,
          quantity, created_at, updated_at
      `;

      if (result.rows.length === 0) {
        return res.status(404).json({ error: 'Card not found' });
      }

      const updatedCard = result.rows[0];

      // Parse colors if it's a JSON string
      if (updatedCard.colors && typeof updatedCard.colors === 'string') {
        try {
          updatedCard.colors = JSON.parse(updatedCard.colors);
        } catch (e) {
          updatedCard.colors = [];
        }
      }

      res.status(200).json(updatedCard);
    } catch (error) {
      console.error('Error updating card:', error);
      res.status(500).json({ error: 'Failed to update card' });
    }
  } else {
    res.status(405).json({ error: 'Method not allowed' });
  }
}