import { useQuery, useMutation, useQueryClient } from '@tanstack/react-query';
import { useSkateRelays } from '@/hooks/useSkateRelays';
import { useNostrPublish } from '@/hooks/useNostrPublish';
import {
  MODERATION_LABEL_NAMESPACE,
  MODERATION_LABEL_HIDDEN,
} from '@/lib/types';

interface UseCrewModerationParams {
  /** Crew addressable coordinate `kind:pubkey:d`. */
  crewCoord: string;
  /** Pubkeys allowed to moderate: the founder + delegated admins. */
  moderators: string[];
  enabled?: boolean;
}

/**
 * Fetch the set of crew-feed post IDs hidden by the crew's moderators
 * (founder + admins) via NIP-32 `hidden` labels.
 *
 * Only labels authored by a listed moderator are honored, so a random user
 * can't hide someone else's post.
 */
export function useCrewModeration({
  crewCoord,
  moderators,
  enabled = true,
}: UseCrewModerationParams) {
  const { querySkateContent, getQueryKeySuffix } = useSkateRelays();

  return useQuery({
    queryKey: ['crew-moderation', crewCoord, moderators.slice().sort().join(','), getQueryKeySuffix()],
    queryFn: async (): Promise<Set<string>> => {
      if (moderators.length === 0) return new Set<string>();
      const signal = AbortSignal.timeout(8000);

      const events = await querySkateContent(
        [
          {
            kinds: [1985],
            authors: moderators,
            '#a': [crewCoord],
            '#l': [MODERATION_LABEL_HIDDEN],
            limit: 200,
          },
        ],
        { signal },
      );

      const modSet = new Set(moderators.map((m) => m.toLowerCase()));
      const hidden = new Set<string>();

      for (const ev of events) {
        // Validate namespace + label + moderator authorship.
        const hasNamespace = ev.tags.some(
          ([n, v]) => n === 'L' && v === MODERATION_LABEL_NAMESPACE,
        );
        const hasLabel = ev.tags.some(
          ([n, v]) => n === 'l' && v === MODERATION_LABEL_HIDDEN,
        );
        const refsCrew = ev.tags.some(([n, v]) => n === 'a' && v === crewCoord);
        if (!hasNamespace || !hasLabel || !refsCrew) continue;
        if (!modSet.has(ev.pubkey.toLowerCase())) continue;

        for (const [n, v] of ev.tags) {
          if (n === 'e' && v) hidden.add(v);
        }
      }

      return hidden;
    },
    enabled: enabled && moderators.length > 0 && !!crewCoord,
    staleTime: 60 * 1000,
  });
}

interface HidePostVars {
  postId: string;
  /** Author of the post being hidden (added as a `p` hint). */
  postAuthor?: string;
}

/**
 * Publish a NIP-32 `hidden` moderation label for a crew-feed post.
 * The caller must be a crew moderator (gate on `useCrewRole().canManage`).
 */
export function useHideCrewPost(crewCoord: string) {
  const { mutateAsync: publish } = useNostrPublish();
  const queryClient = useQueryClient();

  return useMutation({
    mutationFn: async ({ postId, postAuthor }: HidePostVars) => {
      const tags: string[][] = [
        ['L', MODERATION_LABEL_NAMESPACE],
        ['l', MODERATION_LABEL_HIDDEN, MODERATION_LABEL_NAMESPACE],
        ['e', postId],
        ['a', crewCoord],
        ['alt', 'Crew moderation: post hidden'],
      ];
      if (postAuthor) tags.push(['p', postAuthor]);

      await publish({ kind: 1985, content: '', tags });
    },
    onSuccess: () => {
      queryClient.invalidateQueries({ queryKey: ['crew-moderation', crewCoord] });
    },
  });
}