import { dateLocaleCode } from '@/lib/dateFnsI18n';
import { useState } from 'react';
import { Link } from 'react-router-dom';
import { useSeoMeta } from '@unhead/react';
import { nip19 } from 'nostr-tools';
import { Card, CardContent } from '@/components/ui/card';
import { Badge } from '@/components/ui/badge';
import { Button } from '@/components/ui/button';
import { TradeConfirmRow } from '@/components/TradeConfirmRow';
import { Skeleton } from '@/components/ui/skeleton';
import {
  Dialog,
  DialogContent,
  DialogDescription,
  DialogHeader,
  DialogTitle,
} from '@/components/ui/dialog';
import { LoginArea } from '@/components/auth/LoginArea';
import { TradeReputationCard } from '@/components/TradeReputationCard';
import { useCurrentUser } from '@/hooks/useCurrentUser';
import { useAuthor } from '@/hooks/useAuthor';
import { useToast } from '@/hooks/useToast';
import {
  useIncomingTradeRequests,
  usePendingTradeConfirmations,
  useTradeReputation,
  useTradeAttestation,
  parseListingCoord,
} from '@/hooks/useTradeAttestations';
import { genUserName } from '@/lib/genUserName';
import { Handshake, CheckCircle, Loader2, Package, ArrowRight } from 'lucide-react';
import { useTranslation } from '@/contexts/language';

function PeerName({ pubkey }: { pubkey: string }) {
  const author = useAuthor(pubkey);
  const name = author.data?.metadata?.name ?? genUserName(pubkey);
  return (
    <Link to={`/${nip19.npubEncode(pubkey)}`} className="font-bold text-white hover:text-[#ccff00]">
      {name}
    </Link>
  );
}

function listingUrl(pubkey: string, identifier: string): string {
  return `/listing/${pubkey}/${identifier}`;
}

/**
 * `/trades` — one place to manage marketplace trades: incoming confirmation
 * requests (as seller), pending confirmations (as buyer), and your own trade
 * attestation records. Mirrors the DM banners, in a dedicated surface.
 */
export default function TradesPage() {
  const { t } = useTranslation();
  const { user } = useCurrentUser();
  const { toast } = useToast();
  const { publishTrade, isPending: publishing } = useTradeAttestation();

  const { data: incoming, isLoading: loadingIncoming, isError: incomingError } = useIncomingTradeRequests(user?.pubkey);
  const { data: pending, isLoading: loadingPending, isError: pendingError } = usePendingTradeConfirmations(user?.pubkey);
  const { data: reputation, isLoading: loadingRep, isError: repError } = useTradeReputation(user?.pubkey);
  // A relay outage must not look like "nothing waiting" / "no trades".
  const tradeError = incomingError || pendingError || repError;

  const [busy, setBusy] = useState<string | null>(null);
  const [revokeTarget, setRevokeTarget] = useState<{
    listing: { pubkey: string; identifier: string };
    role: 'sold' | 'bought';
    counterparty: string;
  } | null>(null);
  const [revoking, setRevoking] = useState(false);

  useSeoMeta({
    title: t('seoUi.tradesTitle'),
    description: t('seoUi.tradesDesc'),
  });

  const handleConfirmSale = async (
    listing: { pubkey: string; identifier: string },
    requestor: string,
    requestCoord: string,
    rating?: number,
  ) => {
    setBusy(requestCoord);
    try {
      await publishTrade({
        listing,
        role: 'sold',
        counterparty: requestor,
        requestCoord,
        rating,
      });
      toast({ title: t('marketUi.trades.saleConfirmed'), description: t('marketUi.trades.saleConfirmedBody') });
    } catch (e) {
      toast({
        title: t('marketUi.trades.saleConfirmFailed'),
        description: e instanceof Error ? e.message : t('marketUi.trades.somethingWrong'),
        variant: 'destructive',
      });
    } finally {
      setBusy(null);
    }
  };

  const handleConfirmPurchase = async (
    listing: { pubkey: string; identifier: string },
    seller: string,
    coord: string,
    rating?: number,
  ) => {
    setBusy(coord);
    try {
      await publishTrade({ listing, role: 'bought', counterparty: seller, rating });
      toast({ title: t('marketUi.trades.tradeConfirmed'), description: t('marketUi.trades.tradeConfirmedBody') });
    } catch (e) {
      toast({
        title: t('marketUi.trades.tradeConfirmFailed'),
        description: e instanceof Error ? e.message : t('marketUi.trades.somethingWrong'),
        variant: 'destructive',
      });
    } finally {
      setBusy(null);
    }
  };

  const handleRevoke = async () => {
    if (!revokeTarget) return;
    setRevoking(true);
    try {
      await publishTrade({
        listing: revokeTarget.listing,
        role: revokeTarget.role,
        counterparty: revokeTarget.counterparty,
        state: 'revoked',
        note: t('marketUi.trades.revokeNote'),
      });
      toast({
        title: t('marketUi.trades.revoked'),
        description: t('marketUi.trades.revokedBody'),
      });
      setRevokeTarget(null);
    } catch (e) {
      toast({
        title: t('marketUi.trades.revokeFailed'),
        description: e instanceof Error ? e.message : t('marketUi.trades.somethingWrong'),
        variant: 'destructive',
      });
    } finally {
      setRevoking(false);
    }
  };

  if (!user) {
    return (
      <>
        <div className="container mx-auto max-w-md px-4 py-16 text-center space-y-4">
          <Handshake className="mx-auto h-10 w-10 text-gray-600" />
          <h1 className="text-xl font-black uppercase text-white">{t('marketUi.trades.title')}</h1>
          <p className="text-sm text-gray-400">
            {t('marketUi.trades.loginBody')}
          </p>
          <LoginArea className="justify-center" />
        </div>
      </>
    );
  }

  // Attestations this user authored (their own trade records).
  const authored = (reputation?.attestations ?? []).filter((e) => e.pubkey === user.pubkey);

  const actionNeeded =
    (incoming?.length ?? 0) + (pending?.length ?? 0);

  return (
    <>
      <div className="container mx-auto max-w-3xl px-4 py-8 space-y-6">
        <div>
          <h1 className="flex items-center gap-3 text-3xl font-black uppercase text-white">
            <Handshake className="h-8 w-8 text-[#ff6600]" /> {t('marketUi.trades.title')}
          </h1>
          <p className="mt-1 text-sm text-gray-400">
            {t('marketUi.trades.subtitle')}
          </p>
        </div>

        <TradeReputationCard pubkey={user.pubkey} />

        {/* Action needed */}
        <section className="space-y-3">
          <h2 className="text-xs font-black uppercase tracking-widest text-gray-500">
            {t('marketUi.trades.actionNeeded')} {actionNeeded > 0 && `· ${actionNeeded}`}
          </h2>

          {(loadingIncoming || loadingPending) && (
            <div className="space-y-2">
              <Skeleton className="h-20 w-full rounded-2xl" />
              <Skeleton className="h-20 w-full rounded-2xl" />
            </div>
          )}

          {/* Incoming: someone asked you (seller) to record a sale */}
          {incoming?.map((r) => (
            <TradeConfirmRow
              key={r.coord}
              tone="sale"
              icon={Handshake}
              text={<><PeerName pubkey={r.requestor} /> {t('marketUi.trades.askedToConfirmSale')}</>}
              listingUrl={listingUrl(r.listing.pubkey, r.listing.identifier)}
              busy={busy === r.coord}
              disabled={busy === r.coord || publishing}
              actionLabel={t('marketUi.trades.confirmSale')}
              onConfirm={(rating) => handleConfirmSale(r.listing, r.requestor, r.coord, rating)}
            />
          ))}

          {/* Pending: a seller recorded a sale you haven't confirmed */}
          {pending?.map((p) => (
            <TradeConfirmRow
              key={p.coord}
              tone="purchase"
              icon={CheckCircle}
              text={<><PeerName pubkey={p.seller} /> {t('marketUi.trades.recordedSale')}</>}
              listingUrl={listingUrl(p.listing.pubkey, p.listing.identifier)}
              busy={busy === p.coord}
              disabled={busy === p.coord || publishing}
              actionLabel={t('marketUi.trades.confirm')}
              onConfirm={(rating) => handleConfirmPurchase(p.listing, p.seller, p.coord, rating)}
            />
          ))}

          {tradeError && (
            <p className="text-sm text-amber-400">{t('marketUi.loadFailed')}</p>
          )}

          {!tradeError && !loadingIncoming && !loadingPending && actionNeeded === 0 && (
            <p className="text-sm text-gray-500">{t('marketUi.trades.nothingWaiting')}</p>
          )}
        </section>

        {/* Your trade records */}
        <section className="space-y-3">
          <h2 className="text-xs font-black uppercase tracking-widest text-gray-500">
            {t('marketUi.trades.yourRecords')}
          </h2>

          {loadingRep && <Skeleton className="h-16 w-full rounded-2xl" />}

          {repError && (
            <p className="text-sm text-amber-400">{t('marketUi.loadFailed')}</p>
          )}

          {!repError && !loadingRep && authored.length === 0 && (
            <Card className="border-dashed border-white/15 bg-black/60">
              <CardContent className="py-10 text-center">
                <Package className="mx-auto mb-3 h-8 w-8 text-gray-600" />
                <p className="text-sm text-gray-400">
                  {t('marketUi.trades.noTrades')}
                </p>
                <Button asChild variant="outline" className="mt-4 border-white/15">
                  <Link to="/marketplace">{t('marketUi.trades.browseGearSwap')}</Link>
                </Button>
              </CardContent>
            </Card>
          )}

          {authored.map((ev) => {
            const coord = ev.tags.find(([t]) => t === 'a')?.[1];
            const parsed = parseListingCoord(coord);
            const d = ev.tags.find(([t]) => t === 'd')?.[1] ?? '';
            const roleTyped: 'sold' | 'bought' | null = d.includes(':trade:sold:')
              ? 'sold'
              : d.includes(':trade:bought:')
              ? 'bought'
              : null;
            const role = roleTyped === 'sold' ? t('marketUi.trades.roleSold') : roleTyped === 'bought' ? t('marketUi.trades.roleBought') : t('marketUi.trades.roleTrade');
            const state = ev.tags.find(([t]) => t === 's')?.[1] ?? 'valid';
            const stateLabel = state === 'revoked' ? t('marketUi.trades.stateRevoked') : state === 'verifying' ? t('marketUi.trades.stateVerifying') : state;
            const counterparty = ev.tags.find(([t]) => t === 'p')?.[1];
            return (
              <Card key={ev.id} className="bg-black/80 border-white/10">
                <CardContent className="flex items-center gap-3 p-3">
                  <Badge
                    className={
                      roleTyped === 'sold'
                        ? 'bg-orange-500/15 text-orange-400 border border-orange-500/30'
                        : 'bg-[#ccff00]/15 text-[#ccff00] border border-[#ccff00]/30'
                    }
                  >
                    {role}
                  </Badge>
                  <div className="min-w-0 flex-1">
                    <p className="truncate text-sm text-gray-200">
                      {counterparty ? <>{t('marketUi.trades.with')} <PeerName pubkey={counterparty} /></> : t('marketUi.trades.roleTrade').toLowerCase()}
                    </p>
                    <p className="text-[11px] text-gray-500">
                      {new Date(ev.created_at * 1000).toLocaleDateString(dateLocaleCode())}
                      {state !== 'valid' && ` · ${stateLabel}`}
                    </p>
                  </div>
                  {parsed && (
                    <Link
                      to={listingUrl(parsed.pubkey, parsed.identifier)}
                      className="shrink-0 text-xs text-gray-400 hover:text-white"
                    >
                      {t('marketUi.trades.viewListing')} <ArrowRight className="inline h-3 w-3" />
                    </Link>
                  )}
                  {roleTyped && counterparty && parsed && (
                    <button
                      type="button"
                      onClick={() =>
                        setRevokeTarget({
                          listing: { pubkey: parsed.pubkey, identifier: parsed.identifier },
                          role: roleTyped,
                          counterparty,
                        })
                      }
                      className="shrink-0 text-xs text-red-400/70 hover:text-red-400"
                    >
                      {t('marketUi.trades.revoke')}
                    </button>
                  )}
                </CardContent>
              </Card>
            );
          })}
        </section>
      </div>

      <Dialog open={!!revokeTarget} onOpenChange={(o) => !o && setRevokeTarget(null)}>
        <DialogContent className="border-2 border-red-500/30 bg-black sm:max-w-md">
          <DialogHeader>
            <DialogTitle className="text-white">{t('marketUi.trades.revokeTitle')}</DialogTitle>
            <DialogDescription className="text-sm text-gray-400">
              {t('marketUi.trades.revokeBody')}
            </DialogDescription>
          </DialogHeader>
          <div className="flex gap-2 pt-1">
            <Button
              variant="outline"
              onClick={() => setRevokeTarget(null)}
              className="flex-1 border-white/15"
            >
              {t('common.cancel')}
            </Button>
            <Button
              onClick={handleRevoke}
              disabled={revoking}
              className="flex-1 gap-2 bg-red-500 font-bold text-white hover:bg-red-500/90"
            >
              {revoking ? <Loader2 className="h-4 w-4 animate-spin" /> : null}
              {t('marketUi.trades.revoke')}
            </Button>
          </div>
        </DialogContent>
      </Dialog>
    </>
  );
}