import { sql } from '@vercel/postgres';
import { getUserFromRequest } from '../../../lib/permission-middleware';

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 {
    // Get authenticated user
    const user = await getUserFromRequest(req);
    if (!user) {
      return res.status(401).json({ error: 'Authentication required' });
    }

    const { 
      search = '', 
      tcg = 'all', 
      rarity = 'all', 
      set = 'all', 
      valueRange = 'all',
      page = '1', 
      limit = '50' 
    } = req.query;

    const pageNum = parseInt(page) || 1;
    const limitNum = parseInt(limit) || 50;
    const offset = (pageNum - 1) * limitNum;

    // Build WHERE conditions
    let whereConditions = ['uc.user_id = $1'];
    let params = [user.userId];
    let paramIndex = 2;

    if (search.trim()) {
      whereConditions.push(`c.name ILIKE $${paramIndex}`);
      params.push(`%${search.trim()}%`);
      paramIndex++;
    }

    if (tcg !== 'all') {
      whereConditions.push(`c.game = $${paramIndex}`);
      params.push(tcg);
      paramIndex++;
    }

    if (rarity !== 'all') {
      whereConditions.push(`c.rarity = $${paramIndex}`);
      params.push(rarity);
      paramIndex++;
    }

    if (set !== 'all') {
      whereConditions.push(`c.set_name = $${paramIndex}`);
      params.push(set);
      paramIndex++;
    }

    if (valueRange !== 'all') {
      // Handle value range filtering
      const ranges = {
        'under-1': [0, 1],
        '1-5': [1, 5],
        '5-25': [5, 25],
        '25-100': [25, 100],
        'over-100': [100, 999999]
      };
      
      if (ranges[valueRange]) {
        const [min, max] = ranges[valueRange];
        if (valueRange === 'over-100') {
          whereConditions.push(`c.market_price >= $${paramIndex}`);
          params.push(min);
          paramIndex++;
        } else {
          whereConditions.push(`c.market_price >= $${paramIndex} AND c.market_price <= $${paramIndex + 1}`);
          params.push(min, max);
          paramIndex += 2;
        }
      }
    }

    const whereClause = whereConditions.join(' AND ');

    // Get owned cards with user ownership data
    const cardsQuery = `
      SELECT 
        c.id, c.name, c.set_name, c.set_code, c.card_number, c.rarity, c.game,
        c.mana_cost, c.cmc, c.card_type, c.colors, c.oracle_text,
        c.power, c.toughness, c.image_url, c.stock_image_url,
        c.current_price, c.market_price, c.scryfall_id, c.verified,
        uc.quantity as owned_quantity,
        uc.condition,
        uc.created_at as owned_since
      FROM cards c
      INNER JOIN user_cards uc ON c.id = uc.card_id
      WHERE ${whereClause}
      ORDER BY c.name ASC
      LIMIT $${paramIndex} OFFSET $${paramIndex + 1}
    `;

    const countQuery = `
      SELECT COUNT(*) as total
      FROM cards c
      INNER JOIN user_cards uc ON c.id = uc.card_id
      WHERE ${whereClause}
    `;

    // Execute queries
    const result = await sql.query(cardsQuery, [...params, limitNum, offset]);
    const countResult = await sql.query(countQuery, params);

    const total = parseInt(countResult.rows[0].total);
    const totalPages = Math.ceil(total / limitNum);

    // Get filter options for owned cards only
    const filtersQuery = `
      SELECT DISTINCT
        c.game,
        c.rarity,
        c.set_name
      FROM cards c
      INNER JOIN user_cards uc ON c.id = uc.card_id
      WHERE uc.user_id = $1
      ORDER BY c.game, c.rarity, c.set_name
    `;

    const filtersResult = await sql.query(filtersQuery, [user.userId]);
    
    const games = [...new Set(filtersResult.rows.map(row => row.game))].filter(Boolean);
    const rarities = [...new Set(filtersResult.rows.map(row => row.rarity))].filter(Boolean);
    const sets = [...new Set(filtersResult.rows.map(row => row.set_name))].filter(Boolean);

    res.status(200).json({
      cards: result.rows,
      pagination: {
        page: pageNum,
        limit: limitNum,
        total,
        pages: totalPages
      },
      filters: {
        games,
        rarities,
        sets
      }
    });

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