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

export default async function handler(req, res) {
  if (req.method !== 'GET') {
    return res.status(405).json({ error: 'Method not allowed' });
  }

  try {
    const {
      query = '',
      game = '',
      rarity = '',
      set = '',
      minPrice = '',
      maxPrice = '',
      page = 1,
      limit = 50
    } = req.query;

    let result;
    let countResult;

    // Build query based on filters
    if (query && query.trim() && game && game !== 'all' && rarity && rarity !== 'all' && set && set !== 'all') {
      // All filters applied
      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,
          created_at, updated_at
        FROM cards
        WHERE (name ILIKE ${`%${query.trim()}%`} OR oracle_text ILIKE ${`%${query.trim()}%`})
          AND game = ${game}
          AND rarity = ${rarity}
          AND set_name = ${set}
        ORDER BY name ASC
        LIMIT ${parseInt(limit)} OFFSET ${(parseInt(page) - 1) * parseInt(limit)}
      `;
      countResult = await sql`
        SELECT COUNT(*) as total FROM cards
        WHERE (name ILIKE ${`%${query.trim()}%`} OR oracle_text ILIKE ${`%${query.trim()}%`})
          AND game = ${game}
          AND rarity = ${rarity}
          AND set_name = ${set}
      `;
    } else if (query && query.trim() && game && game !== 'all' && rarity && rarity !== 'all') {
      // Query, game, and rarity filters
      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,
          created_at, updated_at
        FROM cards
        WHERE (name ILIKE ${`%${query.trim()}%`} OR oracle_text ILIKE ${`%${query.trim()}%`})
          AND game = ${game}
          AND rarity = ${rarity}
        ORDER BY name ASC
        LIMIT ${parseInt(limit)} OFFSET ${(parseInt(page) - 1) * parseInt(limit)}
      `;
      countResult = await sql`
        SELECT COUNT(*) as total FROM cards
        WHERE (name ILIKE ${`%${query.trim()}%`} OR oracle_text ILIKE ${`%${query.trim()}%`})
          AND game = ${game}
          AND rarity = ${rarity}
      `;
    } else if (query && query.trim() && game && game !== 'all') {
      // Query and game filters
      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,
          created_at, updated_at
        FROM cards
        WHERE (name ILIKE ${`%${query.trim()}%`} OR oracle_text ILIKE ${`%${query.trim()}%`})
          AND game = ${game}
        ORDER BY name ASC
        LIMIT ${parseInt(limit)} OFFSET ${(parseInt(page) - 1) * parseInt(limit)}
      `;
      countResult = await sql`
        SELECT COUNT(*) as total FROM cards
        WHERE (name ILIKE ${`%${query.trim()}%`} OR oracle_text ILIKE ${`%${query.trim()}%`})
          AND game = ${game}
      `;
    } else if (query && query.trim()) {
      // Only query filter
      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,
          created_at, updated_at
        FROM cards
        WHERE name ILIKE ${`%${query.trim()}%`} OR oracle_text ILIKE ${`%${query.trim()}%`}
        ORDER BY name ASC
        LIMIT ${parseInt(limit)} OFFSET ${(parseInt(page) - 1) * parseInt(limit)}
      `;
      countResult = await sql`
        SELECT COUNT(*) as total FROM cards
        WHERE name ILIKE ${`%${query.trim()}%`} OR oracle_text ILIKE ${`%${query.trim()}%`}
      `;
    } else if (game && game !== 'all') {
      // Only game filter
      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,
          created_at, updated_at
        FROM cards
        WHERE game = ${game}
        ORDER BY name ASC
        LIMIT ${parseInt(limit)} OFFSET ${(parseInt(page) - 1) * parseInt(limit)}
      `;
      countResult = await sql`
        SELECT COUNT(*) as total FROM cards
        WHERE game = ${game}
      `;
    } else if (rarity && rarity !== 'all') {
      // Only rarity filter
      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,
          created_at, updated_at
        FROM cards
        WHERE rarity = ${rarity}
        ORDER BY name ASC
        LIMIT ${parseInt(limit)} OFFSET ${(parseInt(page) - 1) * parseInt(limit)}
      `;
      countResult = await sql`
        SELECT COUNT(*) as total FROM cards
        WHERE rarity = ${rarity}
      `;
    } else if (set && set !== 'all') {
      // Only set filter
      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,
          created_at, updated_at
        FROM cards
        WHERE set_name = ${set}
        ORDER BY name ASC
        LIMIT ${parseInt(limit)} OFFSET ${(parseInt(page) - 1) * parseInt(limit)}
      `;
      countResult = await sql`
        SELECT COUNT(*) as total FROM cards
        WHERE set_name = ${set}
      `;
    } else {
      // No filters - get all cards
      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,
          created_at, updated_at
        FROM cards
        ORDER BY name ASC
        LIMIT ${parseInt(limit)} OFFSET ${(parseInt(page) - 1) * parseInt(limit)}
      `;
      countResult = await sql`
        SELECT COUNT(*) as total FROM cards
      `;
    }

    const total = parseInt(countResult.rows[0]?.total || 0);

    // Get unique values for filters
    const [gamesResult, raritiesResult, setsResult] = await Promise.all([
      sql`SELECT DISTINCT game FROM cards WHERE game IS NOT NULL ORDER BY game`,
      sql`SELECT DISTINCT rarity FROM cards WHERE rarity IS NOT NULL ORDER BY rarity`,
      sql`SELECT DISTINCT set_name FROM cards WHERE set_name IS NOT NULL ORDER BY set_name`
    ]);

    res.status(200).json({
      success: true,
      cards: result.rows || [],
      pagination: {
        page: parseInt(page),
        limit: parseInt(limit),
        total,
        pages: Math.ceil(total / limit)
      },
      filters: {
        games: Array.isArray(gamesResult.rows) ? gamesResult.rows.map(row => row.game) : [],
        rarities: Array.isArray(raritiesResult.rows) ? raritiesResult.rows.map(row => row.rarity) : [],
        sets: Array.isArray(setsResult.rows) ? setsResult.rows.map(row => row.set_name) : []
      }
    });

  } catch (error) {
    console.error('Card search error:', error);
    res.status(500).json({ 
      error: 'Search failed', 
      details: error.message 
    });
  }
}