import { useQuery } from '@tanstack/react-query';
import { useNostr } from '@nostrify/react';
import { useSkateRelays } from '@/hooks/useSkateRelays';

/**
 * Hook to track completed sales for a seller.
 * 
 * Sales are tracked via status changes in marketplace listings (kind 30402).
 * A "sale" is counted when a listing has status = 'sold'.
 * 
 * Future enhancement: Could also track via kind 1111 comments with specific tags
 * to confirm receipt/completion of sales.
 */
export function useSellerSales(pubkey: string | undefined) {
  const { querySkateContent, getQueryKeySuffix } = useSkateRelays();

  return useQuery({
    queryKey: ['seller-sales', pubkey, getQueryKeySuffix()],
    queryFn: async () => {
      if (!pubkey) return { totalSales: 0, recentSales: [] };

      const signal = AbortSignal.timeout(8000);

      try {
        // Query all marketplace listings by this seller
        const events = await querySkateContent(
          [
            {
              kinds: [30402], // NIP-99 Classified Listings
              authors: [pubkey],
              '#t': ['skateboarding'],
              limit: 200,
            },
          ],
          { signal }
        );

        // Deduplicate by d-tag (keep latest version of each listing)
        const listingMap = new Map<string, typeof events[0]>();
        for (const event of events) {
          const d = event.tags.find(([name]) => name === 'd')?.[1];
          if (d) {
            const existing = listingMap.get(d);
            if (!existing || event.created_at > existing.created_at) {
              listingMap.set(d, event);
            }
          }
        }

        // Count listings with status = 'sold'
        const allListings = Array.from(listingMap.values());
        const soldListings = allListings.filter(event => {
          const status = event.tags.find(([name]) => name === 'status')?.[1];
          return status === 'sold';
        });

        // Get recent sales (last 5)
        const recentSales = soldListings
          .sort((a, b) => b.created_at - a.created_at)
          .slice(0, 5)
          .map(event => ({
            id: event.id,
            title: event.tags.find(([name]) => name === 'title')?.[1] || 'Unknown item',
            soldAt: event.created_at,
          }));

        return {
          totalSales: soldListings.length,
          recentSales,
        };
      } catch (error) {
        console.warn('[useSellerSales] Error:', error);
        return { totalSales: 0, recentSales: [] };
      }
    },
    enabled: !!pubkey,
    staleTime: 300000, // 5 minutes
    gcTime: 600000, // 10 minutes
  });
}

/**
 * Batch hook to get sales for multiple sellers at once
 */
export function useBatchSellerSales(pubkeys: string[]) {
  const { querySkateContent, getQueryKeySuffix } = useSkateRelays();

  return useQuery({
    queryKey: ['batch-seller-sales', pubkeys.sort().join(','), getQueryKeySuffix()],
    queryFn: async () => {
      if (pubkeys.length === 0) return new Map<string, number>();

      const signal = AbortSignal.timeout(10000);

      try {
        // Query listings for all sellers at once
        const events = await querySkateContent(
          [
            {
              kinds: [30402],
              authors: pubkeys,
              '#t': ['skateboarding'],
              limit: 500,
            },
          ],
          { signal }
        );

        // Group by pubkey and count sold items
        const salesByPubkey = new Map<string, number>();
        
        // Initialize all pubkeys with 0
        for (const pk of pubkeys) {
          salesByPubkey.set(pk, 0);
        }

        // Deduplicate by pubkey+d-tag (keep latest version of each listing)
        const listingMap = new Map<string, typeof events[0]>();
        for (const event of events) {
          const d = event.tags.find(([name]) => name === 'd')?.[1];
          if (d) {
            const key = `${event.pubkey}:${d}`;
            const existing = listingMap.get(key);
            if (!existing || event.created_at > existing.created_at) {
              listingMap.set(key, event);
            }
          }
        }

        // Count sold listings per pubkey
        for (const event of listingMap.values()) {
          const status = event.tags.find(([name]) => name === 'status')?.[1];
          if (status === 'sold') {
            const current = salesByPubkey.get(event.pubkey) || 0;
            salesByPubkey.set(event.pubkey, current + 1);
          }
        }

        return salesByPubkey;
      } catch (error) {
        console.warn('[useBatchSellerSales] Error:', error);
        return new Map<string, number>();
      }
    },
    enabled: pubkeys.length > 0,
    staleTime: 300000,
    gcTime: 600000,
  });
}