import { useQuery } from '@tanstack/react-query';
import { useNostr } from '@nostrify/react';
import { verifyNip05 } from '@/lib/nip05';

/**
 * Batch-verify NIP-05 for a set of skater pubkeys.
 *
 * NIP-05 is a *soft* trust signal, never a gate — the whole directory stays open
 * to everyone. This hook simply fetches each skater's kind-0 metadata, then
 * confirms their `nip05` handle actually resolves to their own pubkey via the
 * domain's `.well-known/nostr.json`. The result powers the "Verified only"
 * filter and the verified badge, letting people *opt in* to a higher-trust view
 * without excluding anyone.
 *
 * Returns a Set of pubkeys that are genuinely NIP-05 verified.
 */
export function useSkaterVerifications(pubkeys: string[]) {
  const { nostr } = useNostr();

  // Stable key so the query only refires when the actual set changes.
  const sortedKey = [...pubkeys].sort().join(',');

  return useQuery({
    queryKey: ['skater-verifications', sortedKey],
    enabled: pubkeys.length > 0,
    staleTime: 10 * 60 * 1000, // 10 min — verification rarely changes
    gcTime: 30 * 60 * 1000,
    queryFn: async (c): Promise<Set<string>> => {
      const verified = new Set<string>();
      if (pubkeys.length === 0) return verified;

      const signal = AbortSignal.any([c.signal, AbortSignal.timeout(12000)]);

      // 1. Fetch kind-0 metadata for all skaters in one query.
      const profiles = await nostr.query([{ kinds: [0], authors: pubkeys }], { signal });

      // Map pubkey -> nip05 handle (newest metadata wins).
      const nip05ByPubkey = new Map<string, string>();
      const seenAt = new Map<string, number>();
      for (const ev of profiles) {
        const prev = seenAt.get(ev.pubkey) ?? -1;
        if (ev.created_at <= prev) continue;
        seenAt.set(ev.pubkey, ev.created_at);
        try {
          const meta = JSON.parse(ev.content) as { nip05?: string };
          if (meta.nip05) nip05ByPubkey.set(ev.pubkey, meta.nip05);
          else nip05ByPubkey.delete(ev.pubkey);
        } catch {
          // ignore malformed metadata
        }
      }

      // 2. Verify each handle against its own pubkey, in parallel.
      const entries = [...nip05ByPubkey.entries()];
      const results = await Promise.all(
        entries.map(async ([pubkey, nip05]) => {
          const res = await verifyNip05(nip05, pubkey, signal).catch(() => ({ status: 'unreachable' as const }));
          return { pubkey, ok: res.status === 'verified' };
        }),
      );

      for (const { pubkey, ok } of results) {
        if (ok) verified.add(pubkey);
      }

      return verified;
    },
  });
}