import { useState } from 'react';
import { useNostr } from '@nostrify/react';
import { useQueryClient } from '@tanstack/react-query';
import { Archive, Loader2, Check, AlertTriangle } from 'lucide-react';
import { Button } from '@/components/ui/button';
import { useCurrentUser } from '@/hooks/useCurrentUser';
import { useSkateRelays } from '@/hooks/useSkateRelays';
import { useNewsletterIssues } from '@/hooks/useNewsletterIssues';
import { useToast } from '@/hooks/useToast';
import { useTranslation } from '@/contexts/language';
import { isAdminPubkey } from '@/lib/admins';
import { buildIssueArticle, issueSlug, type StaticIssueLike } from '@/lib/newsletterArticle';

/**
 * Admin-only one-time backfill: publishes the static archive issues
 * (NEWSLETTER_ISSUES, passed in as a prop to avoid an import cycle with the
 * page) to Nostr as NIP-23 articles. Skips any issue whose slug already exists
 * on-relay, so it's safe to run repeatedly. The rich static page rendering is
 * untouched — this just mirrors the archive onto Nostr for subscribers/readers.
 */
export function NewsletterBackfillPanel({ issues }: { issues?: StaticIssueLike[] }) {
  const { t } = useTranslation();
  const { user } = useCurrentUser();
  const { nostr } = useNostr();
  const { getWriteRelays } = useSkateRelays();
  const { data: liveIssues } = useNewsletterIssues();
  const { toast } = useToast();
  const queryClient = useQueryClient();

  const [running, setRunning] = useState(false);
  const [done, setDone] = useState(false);

  if (!isAdminPubkey(user?.pubkey) || !issues || issues.length === 0) return null;

  // Which static issues aren't on Nostr yet? (match by slug)
  const liveSlugs = new Set((liveIssues ?? []).map((i) => i.identifier));
  const missing = issues.filter((i) => !liveSlugs.has(issueSlug(i.number)));

  const handleBackfill = async () => {
    setRunning(true);
    let published = 0;
    const failures: number[] = [];
    // Publish oldest → newest so numbering reads naturally on relays.
    const ordered = [...missing].sort((a, b) => a.number - b.number);
    for (const issue of ordered) {
      try {
        if (!user) throw new Error(t('walletUi.newsletter.notLoggedIn'));
        const template = buildIssueArticle(issue);
        const event = await user.signer.signEvent({
          kind: template.kind,
          content: template.content,
          tags: template.tags,
          created_at: Math.floor(Date.now() / 1000),
        });
        // Same reason as the composer: publish to the COMMUNITY relay (+ the
        // admin's relays) so readers — logged in or not — actually find it.
        const results = await Promise.allSettled(
          getWriteRelays().map((url) =>
            nostr.relay(url).event(event, { signal: AbortSignal.timeout(8000) }),
          ),
        );
        if (results.every((r) => r.status === 'rejected')) throw new Error('all relays failed');
        published++;
      } catch {
        failures.push(issue.number);
      }
    }
    setRunning(false);
    setDone(true);
    queryClient.invalidateQueries({ queryKey: ['newsletter-issues'] });

    if (failures.length === 0) {
      toast({
        title: t('walletUi.newsletter.backfilled', { count: published }),
        description: t('walletUi.newsletter.backfilledDesc'),
      });
    } else {
      toast({
        title: t('walletUi.newsletter.partialBackfill', { published, failed: failures.length }),
        description: t('walletUi.newsletter.retryFinish', { list: failures.map((n) => `#${String(n).padStart(3, '0')}`).join(', ') }),
        variant: 'destructive',
      });
      setDone(false);
    }
  };

  if (missing.length === 0) {
    return (
      <p className="mt-1 flex items-center gap-1.5 text-[10px] font-bold uppercase tracking-widest text-green-500/70">
        <Check className="h-3 w-3" /> {t('walletUi.newsletter.archiveSynced')}
      </p>
    );
  }

  return (
    <div className="mt-3 w-full max-w-sm rounded-xl border border-yellow-500/30 bg-yellow-500/[0.06] p-3 text-left">
      <div className="flex items-start gap-2">
        <AlertTriangle className="mt-0.5 h-4 w-4 flex-shrink-0 text-yellow-500" />
        <div className="min-w-0">
          <p className="text-xs font-bold text-yellow-200">
            {t('walletUi.newsletter.missingCount', { count: missing.length })}
          </p>
          <p className="mt-0.5 text-[11px] leading-snug text-gray-400">
            {t('walletUi.newsletter.backfillDesc', { list: missing.map((i) => `#${String(i.number).padStart(3, '0')}`).join(', ') })}
          </p>
          <Button
            size="sm"
            onClick={handleBackfill}
            disabled={running || done}
            className="mt-2 h-8 gap-1.5 bg-yellow-500 font-black uppercase text-[11px] text-black hover:bg-yellow-400"
          >
            {running ? (
              <Loader2 className="h-3.5 w-3.5 animate-spin" />
            ) : done ? (
              <Check className="h-3.5 w-3.5" />
            ) : (
              <Archive className="h-3.5 w-3.5" />
            )}
            {running ? t('walletUi.newsletter.publishing') : done ? t('common.done') : t('walletUi.newsletter.backfill', { count: missing.length })}
          </Button>
        </div>
      </div>
    </div>
  );
}