import '../style.scss';
import { Metadata } from 'next';
import Link from 'next/link';
import PaperNav from '../_components/PaperNav';
import { fetchPaperLeaderboard } from '@/lib/api/paper';
import { changeDirection, changeSymbol } from '@/lib/utils/stock';
import { formatBpPercent, formatBpAbs, bpDirection } from '@/lib/utils/paper';
import type { PaperLeaderboardSort, PaperLeaderboardPeriod } from '@/types/paper';

export const metadata: Metadata = {
	title: '모의투자 리더보드 — 개미투자',
	description: '수익률·승률·MDD 기준 모의투자 순위 (주간/월간/전체)'
};

const SORT_TABS: { value: PaperLeaderboardSort; label: string }[] = [
	{ value: 'return', label: '수익률' },
	{ value: 'winrate', label: '승률' },
	{ value: 'mdd', label: 'MDD' }
];

const PERIOD_TABS: { value: PaperLeaderboardPeriod; label: string }[] = [
	{ value: 'week', label: '주간' },
	{ value: 'month', label: '월간' },
	{ value: 'all', label: '전체' }
];

const PAGE_SIZE = 50;

type Props = {
	searchParams: Promise<{
		sort?: string;
		period?: string;
		page?: string;
	}>;
};

export default async function PaperLeaderboardPage({ searchParams }: Props)
{
	const query = await searchParams;
	const sort: PaperLeaderboardSort = SORT_TABS.some(c => c.value === query.sort) ? (query.sort as PaperLeaderboardSort) : 'return';
	const period: PaperLeaderboardPeriod = PERIOD_TABS.some(c => c.value === query.period) ? (query.period as PaperLeaderboardPeriod) : 'all';
	const page = Math.max(Number(query.page) || 1, 1);

	const res = await fetchPaperLeaderboard({ sort, period, page });
	const rows = res.success ? (res.data?.rows ?? []) : [];

	const buildHref = (next: { sort?: PaperLeaderboardSort; period?: PaperLeaderboardPeriod }) => {
		const params = new URLSearchParams();
		params.set('sort', next.sort ?? sort);
		params.set('period', next.period ?? period);
		return `/paper/leaderboard?${params.toString()}`;
	};

	return (
		<div className='paper'>
			<div className='paper__head'>
				<h1 className='paper__title'>리더보드</h1>
				<span className='paper__subtitle'>순위는 명예·프로필 배지만 부여됩니다 (별도 상금 없음)</span>
			</div>

			<PaperNav />

			<div className='paper__tab-group'>
				<span className='paper__tab-group-label'>정렬</span>
				{SORT_TABS.map(tab => (
					<Link
						key={tab.value}
						href={buildHref({ sort: tab.value })}
						className={`paper__tab${sort === tab.value ? ' paper__tab--active' : ''}`}
						{...(sort === tab.value ? { 'aria-current': 'page' as const } : {})}
					>
						{tab.label}
					</Link>
				))}
			</div>

			<div className='paper__tab-group'>
				<span className='paper__tab-group-label'>기간</span>
				{PERIOD_TABS.map(tab => (
					<Link
						key={tab.value}
						href={buildHref({ period: tab.value })}
						className={`paper__tab${period === tab.value ? ' paper__tab--active' : ''}`}
						{...(period === tab.value ? { 'aria-current': 'page' as const } : {})}
					>
						{tab.label}
					</Link>
				))}
			</div>

			{!res.success ? (
				<div className='paper__error' role='alert'>리더보드를 불러오지 못했습니다. 잠시 후 다시 시도해 주세요.</div>
			) : rows.length === 0 ? (
				<div className='paper__empty'>아직 등재된 참여자가 없습니다.</div>
			) : (
				<div className='paper__table-wrap'>
					<table className='paper__table'>
						<caption className='sr-only'>모의투자 리더보드 — 순위·닉네임·수익률·승률·MDD·체결수</caption>
						<thead>
							<tr>
								<th className='paper__th--center'>순위</th>
								<th className='paper__th--left'>닉네임</th>
								<th>수익률</th>
								<th>승률</th>
								<th>MDD</th>
								<th>체결수</th>
							</tr>
						</thead>
						<tbody>
							{rows.map(row => {
								const dir = bpDirection(row.returnBp);
								const symbol = changeSymbol(changeDirection(row.returnBp));

								return (
									<tr key={row.memberSID}>
										<td className='paper__td--center paper__rank'>{row.rank}</td>
										<td className='paper__td--left'>
											<span className='paper__nick'>
												{row.thumb ? (
													// eslint-disable-next-line @next/next/no-img-element
													<img src={row.thumb} alt='' className='paper__nick-thumb' />
												) : null}
												<Link href={`/user/${row.memberSID}/paper`} className='paper__nick-name'>
													{row.nickname || '익명'}
												</Link>
											</span>
										</td>
										<td className={`paper__value--${dir}`}>{symbol} {formatBpPercent(row.returnBp)}</td>
										<td>{formatBpAbs(row.winRateBp)}</td>
										<td className='paper__value--down'>{formatBpAbs(row.mddBp)}</td>
										<td>{row.fillCount.toLocaleString()}</td>
									</tr>
								);
							})}
						</tbody>
					</table>
				</div>
			)}

			{res.success && rows.length > 0 && (
				<nav className='paper__actions' aria-label='페이지'>
					{page > 1 && (
						<Link href={`/paper/leaderboard?sort=${sort}&period=${period}&page=${page - 1}`} className='paper__btn paper__btn--sm'>이전</Link>
					)}
					{rows.length >= PAGE_SIZE && (
						<Link href={`/paper/leaderboard?sort=${sort}&period=${period}&page=${page + 1}`} className='paper__btn paper__btn--sm'>다음</Link>
					)}
				</nav>
			)}
		</div>
	);
}