'use client';

import './world-map.scss';
import { useMemo, useState } from 'react';
import { EXCHANGE_GEO, moveDir, formatFlucRate, formatIndexClose, type WorldIndexRow } from '@/types/worldIndex';

// 등거리(plate carrée) 투영 — viewBox 1000×500 (경도 -180~180, 위도 90~-90)
const VW = 1000;
const VH = 500;
const project = (lat: number, lng: number) => ({
	x: ((lng + 180) / 360) * VW,
	y: ((90 - lat) / 180) * VH
});

// 스타일라이즈드(저폴리) 대륙 실루엣 — 지리적 근사(정밀 지도 아님). viewBox 좌표계 직접 좌표.
const CONTINENTS: string[] = [
	// 북미
	'140,84 210,66 302,70 314,104 288,126 302,158 274,176 250,156 248,196 226,210 200,236 188,222 212,198 214,172 190,156 166,130 150,106',
	// 그린란드
	'330,54 366,48 380,74 352,92 332,76',
	// 남미
	'300,266 340,258 364,278 380,300 366,336 344,384 320,414 304,420 296,388 300,342 290,300 292,278',
	// 유럽
	'470,92 518,84 550,94 560,116 540,134 512,150 496,134 480,142 470,116',
	// 아프리카
	'486,176 548,166 588,188 596,236 570,300 542,358 520,350 508,298 500,244 488,206',
	// 아시아(중동~러시아~중국~인도 벌지)
	'560,92 634,68 714,70 792,82 858,98 900,120 872,140 852,150 872,178 830,198 800,178 810,214 776,234 748,208 720,180 700,206 686,182 656,168 628,146 600,150 580,128 566,110',
	// 일본
	'878,136 896,150 886,172 872,158',
	// 인도네시아/동남아 도서
	'756,234 806,230 830,248 800,264 760,258',
	// 호주
	'800,316 858,306 928,332 916,362 856,378 812,362 796,336'
];

// 위/경도 격자선
const LNG_LINES = [-150, -120, -90, -60, -30, 0, 30, 60, 90, 120, 150];
const LAT_LINES = [-60, -30, 0, 30, 60];

type Props = {
	rows: WorldIndexRow[];
};

type Pin = {
	row: WorldIndexRow;
	label: string;
	x: number;
	y: number;
	dir: 'up' | 'down' | 'flat';
	radius: number;
};

export default function WorldMarketMap({ rows }: Props)
{
	const [active, setActive] = useState<string|null>(null);

	// 좌표를 아는 국가만 핀으로. 등락 크기에 따라 반경 가변(6~10).
	const pins = useMemo<Pin[]>(() => {
		return rows
			.map((row) => {
				const geo = EXCHANGE_GEO[row.countryCode];
				if (!geo) {
					return null;
				}
				const { x, y } = project(geo.lat, geo.lng);
				const radius = Math.min(10, 6 + Math.abs(row.flucRateBp) / 80);
				return { row, label: geo.label, x, y, dir: moveDir(row.flucRateBp), radius };
			})
			.filter((c): c is Pin => c !== null);
	}, [rows]);

	// 기준일 = 핀 중 가장 최근 거래일
	const asOf = useMemo(() => {
		return rows.reduce<string|null>((max, c) => (max === null || c.tradeDate > max ? c.tradeDate : max), null);
	}, [rows]);

	const activePin = pins.find((c) => c.row.countryCode === active) ?? null;

	return (
		<section className='world-map' aria-label='세계 주요국 증시지수'>
			<div className='world-map__head'>
				<h2 className='world-map__title'>세계 증시</h2>
				<div className='world-map__meta'>
					<span className='world-map__legend'>
						<i className='world-map__dot world-map__dot--up' aria-hidden='true' />상승
						<i className='world-map__dot world-map__dot--down' aria-hidden='true' />하락
					</span>
					{asOf && <span className='world-map__asof'>기준 {asOf}</span>}
				</div>
			</div>

			<div className='world-map__stage'>
				{pins.length === 0 ? (
					<div className='world-map__empty'>표시할 지수 데이터가 없습니다.</div>
				) : (
					<svg
						className='world-map__svg'
						viewBox={`0 0 ${VW} ${VH}`}
						role='img'
						aria-label='세계지도 위 주요국 증시지수 핀'
						preserveAspectRatio='xMidYMid meet'
					>
						<defs>
							<radialGradient id='wm-ocean' cx='50%' cy='38%' r='75%'>
								<stop offset='0%' stopColor='var(--az-map-ocean-1)' />
								<stop offset='100%' stopColor='var(--az-map-ocean-2)' />
							</radialGradient>
							<filter id='wm-glow' x='-60%' y='-60%' width='220%' height='220%'>
								<feGaussianBlur stdDeviation='4' result='b' />
								<feMerge>
									<feMergeNode in='b' />
									<feMergeNode in='SourceGraphic' />
								</feMerge>
							</filter>
						</defs>

						{/* 대양 */}
						<rect x='0' y='0' width={VW} height={VH} rx='16' fill='url(#wm-ocean)' />

						{/* 격자선 */}
						<g className='world-map__grid'>
							{LNG_LINES.map((lng) => {
								const x = ((lng + 180) / 360) * VW;
								return <line key={`lng-${lng}`} x1={x} y1='0' x2={x} y2={VH} />;
							})}
							{LAT_LINES.map((lat) => {
								const y = ((90 - lat) / 180) * VH;
								return <line key={`lat-${lat}`} x1='0' y1={y} x2={VW} y2={y} />;
							})}
						</g>

						{/* 대륙 */}
						<g className='world-map__land'>
							{CONTINENTS.map((points, i) => (
								<polygon key={i} points={points} />
							))}
						</g>

						{/* 핀 */}
						<g className='world-map__pins'>
							{pins.map((pin) => {
								const isActive = pin.row.countryCode === active;
								return (
									<g
										key={pin.row.countryCode}
										className={`world-map__pin world-map__pin--${pin.dir}${isActive ? ' is-active' : ''}`}
										transform={`translate(${pin.x} ${pin.y})`}
										role='button'
										tabIndex={0}
										aria-label={`${pin.label} ${pin.row.name} ${formatFlucRate(pin.row.flucRateBp)}`}
										onMouseEnter={() => setActive(pin.row.countryCode)}
										onMouseLeave={() => setActive((cur) => (cur === pin.row.countryCode ? null : cur))}
										onFocus={() => setActive(pin.row.countryCode)}
										onBlur={() => setActive((cur) => (cur === pin.row.countryCode ? null : cur))}
									>
										{pin.dir !== 'flat' && <circle className='world-map__pulse' r={pin.radius} />}
										<circle className='world-map__pin-dot' r={pin.radius} />
										<circle className='world-map__pin-core' r={pin.radius / 2.6} />
									</g>
								);
							})}
						</g>
					</svg>
				)}

				{/* 툴팁 — 활성 핀 기준 % 위치 (viewBox 비율) */}
				{activePin && (
					<div
						className='world-map__tip'
						style={{ left: `${(activePin.x / VW) * 100}%`, top: `${(activePin.y / VH) * 100}%` }}
						role='status'
					>
						<div className='world-map__tip-head'>
							<span className='world-map__tip-country'>{activePin.label}</span>
							<span className='world-map__tip-name'>{activePin.row.name}</span>
						</div>
						<div className='world-map__tip-close'>{formatIndexClose(activePin.row.close)}</div>
						<div className={`world-map__tip-change world-map__tip-change--${activePin.dir}`}>
							{formatFlucRate(activePin.row.flucRateBp)}
							<span className='world-map__tip-exch'>{activePin.row.exchangeName}</span>
						</div>
					</div>
				)}
			</div>
		</section>
	);
}