'use client';

import { useFormatter, useTranslations } from 'next-intl';
import { useCallback, useEffect, useState } from 'react';

import { isApiClientError } from '@sport/api-client';
import { PERMISSIONS, type AdminReview, type ReviewStatus } from '@sport/types';
import { Badge, Button, EmptyState, Input, Rating, SegmentedControl, Skeleton } from '@sport/ui';

import { useSession } from '@/features/auth/session-provider';
import { browserApi } from '@/lib/api';
import { formatDateTime } from '@/lib/format';

const STATUS_FILTERS = ['PENDING', 'APPROVED', 'REJECTED', 'ALL'] as const satisfies readonly (
  ReviewStatus | 'ALL'
)[];
type StatusFilter = (typeof STATUS_FILTERS)[number];

const STATUS_VARIANT = {
  PENDING: 'warning',
  APPROVED: 'success',
  REJECTED: 'neutral',
} as const;

export function ReviewsQueue() {
  const t = useTranslations('reviews');
  const format = useFormatter();
  const { can } = useSession();

  const [reviews, setReviews] = useState<AdminReview[] | null>(null);
  const [error, setError] = useState<string | null>(null);
  const [query, setQuery] = useState('');
  // Pending by default: this screen exists to empty a queue, not to browse.
  const [status, setStatus] = useState<StatusFilter>('PENDING');
  const [busyId, setBusyId] = useState<string | null>(null);

  const load = useCallback(async () => {
    try {
      const result = await browserApi.reviewsAdmin.list({
        perPage: 50,
        q: query.trim() || undefined,
        status: status === 'ALL' ? undefined : status,
      });
      setReviews([...result.items]);
      setError(null);
    } catch (caught) {
      setError(isApiClientError(caught) ? caught.message : t('loadFailed'));
    }
  }, [query, status, t]);

  useEffect(() => {
    let cancelled = false;
    const timer = setTimeout(() => {
      if (!cancelled) void load();
    }, 250);

    return () => {
      cancelled = true;
      clearTimeout(timer);
    };
  }, [load]);

  async function decide(id: string, decision: 'APPROVED' | 'REJECTED', note?: string) {
    setBusyId(id);
    setError(null);

    try {
      await browserApi.reviewsAdmin.moderate(id, { status: decision, note: note ?? null });
      await load();
    } catch (caught) {
      setError(isApiClientError(caught) ? caught.message : t('moderateFailed'));
    } finally {
      setBusyId(null);
    }
  }

  if (!can(PERMISSIONS.REVIEW_MODERATE)) {
    return <p className="text-ink-500 text-sm">{t('noPermission')}</p>;
  }

  return (
    <div className="space-y-4">
      <div className="flex flex-wrap items-center gap-3">
        <Input
          value={query}
          onChange={(event) => setQuery(event.target.value)}
          placeholder={t('searchPlaceholder')}
          className="max-w-xs"
          aria-label={t('searchPlaceholder')}
        />

        <SegmentedControl
          label={t('searchPlaceholder')}
          value={status}
          onChange={setStatus}
          options={STATUS_FILTERS.map((value) => ({ value, label: t(`filter.${value}`) }))}
        />
      </div>

      {error ? (
        <p role="alert" className="text-danger text-sm">
          {error}
        </p>
      ) : null}

      {!reviews ? (
        <div className="space-y-2" aria-busy="true">
          <Skeleton className="h-28 w-full" />
          <Skeleton className="h-28 w-full" />
        </div>
      ) : reviews.length === 0 ? (
        <EmptyState title={status === 'PENDING' ? t('emptyQueue') : t('empty')} />
      ) : (
        <ul className="space-y-3">
          {reviews.map((review) => (
            <ReviewCard
              key={review.id}
              review={review}
              busy={busyId === review.id}
              onDecide={decide}
              t={t}
              format={format}
            />
          ))}
        </ul>
      )}
    </div>
  );
}

function ReviewCard({
  review,
  busy,
  onDecide,
  t,
  format,
}: {
  review: AdminReview;
  busy: boolean;
  onDecide: (id: string, decision: 'APPROVED' | 'REJECTED', note?: string) => void;
  t: ReturnType<typeof useTranslations<'reviews'>>;
  format: ReturnType<typeof useFormatter>;
}) {
  const [rejecting, setRejecting] = useState(false);
  const [note, setNote] = useState('');

  return (
    <li className="border-ink-200 space-y-3 border bg-white p-4">
      <div className="flex flex-wrap items-start justify-between gap-3">
        <div className="space-y-1">
          <div className="flex items-center gap-2">
            <Rating value={review.rating} size="sm" />
            <span className="text-sm font-semibold">{review.title || t('untitled')}</span>
          </div>
          <p className="text-ink-500 text-xs">
            {review.productName} · {review.variantTitle} ·{' '}
            <span className="font-mono">#{review.orderNumber}</span>
          </p>
        </div>
        <Badge variant={STATUS_VARIANT[review.status]}>{t(`status.${review.status}`)}</Badge>
      </div>

      {review.body ? (
        <p className="text-ink-700 whitespace-pre-line text-sm">{review.body}</p>
      ) : (
        <p className="text-ink-500 text-sm italic">{t('noBody')}</p>
      )}

      <p className="text-ink-500 text-xs">
        {t('by', { name: review.authorName })} · {formatDateTime(review.createdAt, format)}
        {review.moderatedByName ? ` · ${t('moderatedBy', { name: review.moderatedByName })}` : null}
      </p>

      {review.moderationNote ? (
        <p className="border-ink-200 text-ink-500 border-l-2 pl-3 text-xs">
          {t('note')}: {review.moderationNote}
        </p>
      ) : null}

      {rejecting ? (
        <div className="flex flex-wrap items-center gap-2">
          <Input
            value={note}
            onChange={(event) => setNote(event.target.value)}
            placeholder={t('notePlaceholder')}
            className="max-w-sm"
            aria-label={t('notePlaceholder')}
          />
          <Button
            variant="destructive"
            size="sm"
            disabled={busy}
            onClick={() => onDecide(review.id, 'REJECTED', note.trim() || undefined)}
          >
            {t('confirmReject')}
          </Button>
          <Button variant="ghost" size="sm" onClick={() => setRejecting(false)}>
            {t('cancel')}
          </Button>
        </div>
      ) : (
        <div className="flex gap-2">
          {/*
            Both actions stay available on an already-moderated review: a
            decision made in haste has to be reversible, and the aggregate is
            recomputed from scratch on every decision so reversing one is safe.
          */}
          <Button
            size="sm"
            disabled={busy || review.status === 'APPROVED'}
            onClick={() => onDecide(review.id, 'APPROVED')}
          >
            {t('approve')}
          </Button>
          <Button
            variant="outline"
            size="sm"
            disabled={busy || review.status === 'REJECTED'}
            onClick={() => setRejecting(true)}
          >
            {t('reject')}
          </Button>
        </div>
      )}
    </li>
  );
}