/** 오목 화면 (docs/games/omok.md §9). */
import { useEffect, useMemo, useRef, useState } from 'react';
import type { OmokOptions, OmokView, Pt } from '@bg/games/omok';
import type { PublicUser } from '@bg/shared/lite';
import { Avatar, ConfirmSheet, Sheet } from '../../components/ui';
import { TurnTimer, useServerNow } from '../../components/TurnTimer';
import { haptic, sounds } from '../../lib/feedback';
import type { BoardProps, GameUI, OptionsProps } from '../types';

type Color = 'black' | 'white';
const COLOR_KO: Record<Color, string> = { black: '흑', white: '백' };
const COLS = 'ABCDEFGHIJKLMNOPQRS';
const label = (size: number, p: Pt) => `${COLS[p.x]}${size - p.y}`;
const RULE_KO: Record<OmokOptions['ruleSet'], string> = { korean: '한국식', renju: '렌주룰', free: '자유룰' };

function stars(size: number): Pt[] {
  const s = size === 19 ? [3, 9, 15] : [3, 7, 11];
  return s.flatMap((x) => s.map((y) => ({ x, y })));
}

function Stone({ color, cx, cy, r, ghost }: { color: Color; cx: number; cy: number; r: number; ghost?: boolean }) {
  return (
    <g opacity={ghost ? 0.55 : 1}>
      <circle cx={cx} cy={cy} r={r} fill={color === 'black' ? '#151515' : '#fbfbf8'} stroke={color === 'black' ? '#000' : '#666'} strokeWidth={0.06} />
      {color === 'black' ? (
        <circle cx={cx - r * 0.3} cy={cy - r * 0.3} r={r * 0.28} fill="#fff" opacity={0.15} />
      ) : (
        <circle cx={cx + r * 0.25} cy={cy + r * 0.25} r={r * 0.6} fill="#000" opacity={0.05} />
      )}
    </g>
  );
}

function OmokBoard({ view: v, me, players, act, pending, deadline, tapConfirm }: BoardProps<OmokView>) {
  const n = v.size;
  const myTurn = v.phase === 'playing' && v.myColor === v.turn;
  const [preview, setPreview] = useState<Pt | null>(null);
  const [cursor, setCursor] = useState<Pt>({ x: (n - 1) / 2, y: (n - 1) / 2 });
  const [confirm, setConfirm] = useState<null | 'resign' | 'draw'>(null);
  const [announce, setAnnounce] = useState('');
  const [kbd, setKbd] = useState(false);
  const svgRef = useRef<SVGSVGElement>(null);
  const prevCount = useRef(v.moveCount);
  const prevTurn = useRef(v.turn);

  const forbidden = useMemo(() => new Set(v.forbidden.map((p) => p.y * n + p.x)), [v.forbidden, n]);

  // Sounds, vibration and screen-reader announcements on new moves.
  useEffect(() => {
    if (v.moveCount > prevCount.current && v.lastMove) {
      sounds.stone();
      const who = v.moves[v.moves.length - 1]!.color;
      setAnnounce(`${COLOR_KO[who]}이 ${label(n, v.lastMove)}에 두었어요.`);
    }
    if (v.phase === 'playing' && myTurn && (prevTurn.current !== v.turn || v.moveCount === 0) && v.moveCount !== prevCount.current) {
      haptic(40);
      if (document.visibilityState === 'hidden') sounds.myTurn();
    }
    prevCount.current = v.moveCount;
    prevTurn.current = v.turn;
    setPreview(null);
  }, [v.moveCount, v.turn]); // eslint-disable-line react-hooks/exhaustive-deps

  const canPlace = (p: Pt) =>
    myTurn && !pending && v.board[p.y * n + p.x] === 0 && !forbidden.has(p.y * n + p.x) && (!v.firstMoveCenter || v.moveCount > 0 || (p.x === (n - 1) / 2 && p.y === (n - 1) / 2));

  const place = (p: Pt) => {
    act({ type: 'place', x: p.x, y: p.y });
    setPreview(null);
  };

  const tap = (p: Pt) => {
    setCursor(p);
    if (!myTurn) return;
    if (v.board[p.y * n + p.x] !== 0) return;
    if (forbidden.has(p.y * n + p.x)) {
      haptic([30, 30, 30]);
      setAnnounce('여기는 금수 자리라 둘 수 없어요.');
    }
    if (!tapConfirm) {
      place(p);
      return;
    }
    if (preview && preview.x === p.x && preview.y === p.y) place(p);
    else setPreview(p);
  };

  const pointToCell = (e: React.PointerEvent<SVGSVGElement>): Pt | null => {
    const svg = svgRef.current;
    if (!svg) return null;
    const pt = svg.createSVGPoint();
    pt.x = e.clientX;
    pt.y = e.clientY;
    const loc = pt.matrixTransform(svg.getScreenCTM()!.inverse());
    const x = Math.round(loc.x);
    const y = Math.round(loc.y);
    return x >= 0 && y >= 0 && x < n && y < n ? { x, y } : null;
  };

  const onKey = (e: React.KeyboardEvent) => {
    setKbd(true);
    const d: Record<string, [number, number]> = { ArrowLeft: [-1, 0], ArrowRight: [1, 0], ArrowUp: [0, -1], ArrowDown: [0, 1] };
    if (d[e.key]) {
      e.preventDefault();
      setCursor((c) => ({ x: Math.min(n - 1, Math.max(0, c.x + d[e.key]![0])), y: Math.min(n - 1, Math.max(0, c.y + d[e.key]![1])) }));
    } else if (e.key === 'Enter' || e.key === ' ') {
      e.preventDefault();
      if (canPlace(cursor)) place(cursor);
    }
  };

  const winSet = new Set((v.winLine ?? []).map((p) => p.y * n + p.x));
  const incoming =
    v.phase === 'playing' && v.myColor
      ? v.undo.pending && v.undo.pending.by !== v.myColor
        ? 'undo'
        : v.draw.pendingBy && v.draw.pendingBy !== v.myColor
          ? 'draw'
          : null
      : null;
  const outgoing = v.myColor && (v.undo.pending?.by === v.myColor || v.draw.pendingBy === v.myColor);
  const undoLeft = v.myColor ? v.undo.remaining[v.myColor] : null;
  const opp: Color | null = v.myColor ? (v.myColor === 'black' ? 'white' : 'black') : null;

  const pad = 0.6;
  return (
    <div className="stack" style={{ gap: 10 }}>
      <PlayerBar view={v} color={opp ?? 'white'} players={players} deadline={deadline} me={me} />
      <div className="board-wrap">
        <svg
          ref={svgRef}
          viewBox={`${-pad} ${-pad} ${n - 1 + 2 * pad} ${n - 1 + 2 * pad}`}
          style={{ width: '100%', display: 'block', background: 'var(--wood)', borderRadius: 12, touchAction: 'manipulation', cursor: myTurn ? 'pointer' : 'default' }}
          onPointerUp={(e) => {
            setKbd(false);
            const p = pointToCell(e);
            if (p) tap(p);
          }}
          tabIndex={0}
          role="grid"
          aria-label={`오목판 ${n}줄. 방향키로 움직이고 Enter로 둡니다. 현재 위치 ${label(n, cursor)}`}
          onKeyDown={onKey}
        >
          {Array.from({ length: n }, (_, i) => (
            <g key={i} stroke="var(--wood-line)" strokeWidth={i === 0 || i === n - 1 ? 0.06 : 0.035}>
              <line x1={0} y1={i} x2={n - 1} y2={i} />
              <line x1={i} y1={0} x2={i} y2={n - 1} />
            </g>
          ))}
          {stars(n).map((p) => (
            <circle key={`s${p.x}-${p.y}`} cx={p.x} cy={p.y} r={0.11} fill="var(--wood-line)" />
          ))}
          {myTurn && v.hints?.urgent.map((p) => <circle key={`u${p.x}-${p.y}`} cx={p.x} cy={p.y} r={0.42} fill="none" stroke="#dc2626" strokeWidth={0.09} />)}
          {myTurn && v.hints?.warn.map((p) => <circle key={`w${p.x}-${p.y}`} cx={p.x} cy={p.y} r={0.38} fill="none" stroke="#f59e0b" strokeWidth={0.07} strokeDasharray="0.15 0.1" />)}
          {v.forbidden.map((p) => (
            <g key={`f${p.x}-${p.y}`} stroke="#b91c1c" strokeWidth={0.08} opacity={0.8}>
              <line x1={p.x - 0.2} y1={p.y - 0.2} x2={p.x + 0.2} y2={p.y + 0.2} />
              <line x1={p.x + 0.2} y1={p.y - 0.2} x2={p.x - 0.2} y2={p.y + 0.2} />
            </g>
          ))}
          {v.board.map((c, i) =>
            c === 0 ? null : <Stone key={i} color={c === 1 ? 'black' : 'white'} cx={i % n} cy={Math.floor(i / n)} r={0.46} />,
          )}
          {v.lastMove && <circle cx={v.lastMove.x} cy={v.lastMove.y} r={0.13} fill="#ef4444" />}
          {[...winSet].map((i) => (
            <circle key={`win${i}`} cx={i % n} cy={Math.floor(i / n)} r={0.5} fill="none" stroke="#22c55e" strokeWidth={0.1} />
          ))}
          {preview && v.myColor && <Stone color={v.myColor} cx={preview.x} cy={preview.y} r={0.46} ghost />}
          {myTurn && kbd && <rect x={cursor.x - 0.5} y={cursor.y - 0.5} width={1} height={1} fill="none" stroke="var(--focus)" strokeWidth={0.06} className="kbd-cursor" />}
        </svg>
      </div>
      <p className="sr-only" aria-live="polite">
        {announce}
      </p>

      {preview && myTurn && (
        <div className="row" style={{ justifyContent: 'center' }}>
          <button className="btn btn-primary" style={{ flex: 2 }} disabled={!canPlace(preview)} onClick={() => place(preview)}>
            {forbidden.has(preview.y * n + preview.x) ? '여기는 둘 수 없어요' : `${label(n, preview)}에 두기`}
          </button>
          <button className="btn btn-secondary" style={{ flex: 1 }} onClick={() => setPreview(null)}>
            취소
          </button>
        </div>
      )}

      <PlayerBar view={v} color={v.myColor ?? 'black'} players={players} deadline={deadline} me={me} />

      {v.phase === 'playing' && v.myColor && (
        <div className="row" style={{ justifyContent: 'center' }}>
          {v.undo.allowed && (
            <button
              className="btn btn-secondary btn-sm"
              disabled={!!outgoing || undoLeft === 0 || !v.moves.some((m) => m.color === v.myColor)}
              onClick={() => act({ type: 'requestUndo' })}
            >
              ↩ 무르기{undoLeft !== null ? ` (${undoLeft}번 남음)` : ''}
            </button>
          )}
          {v.draw.allowed && (
            <button className="btn btn-secondary btn-sm" disabled={!!outgoing} onClick={() => setConfirm('draw')}>
              🤝 무승부 제안
            </button>
          )}
          <button className="btn btn-danger btn-sm" onClick={() => setConfirm('resign')}>
            🏳 기권
          </button>
        </div>
      )}
      {outgoing && (
        <div className="card row" style={{ justifyContent: 'space-between' }}>
          <span>상대의 답을 기다리는 중이에요…</span>
          <button className="btn btn-ghost" onClick={() => act({ type: 'cancelOffer' })}>
            요청 취소
          </button>
        </div>
      )}
      {incoming && (
        <Sheet onClose={() => {}} label="상대의 요청">
          <h2>{incoming === 'undo' ? `상대가 ${v.undo.pending!.plies}수 무르기를 요청했어요` : '상대가 무승부를 제안했어요'}</h2>
          <p className="muted">{incoming === 'undo' ? '수락하면 돌이 되돌아가요.' : '수락하면 이 판은 무승부로 끝나요.'}</p>
          <div className="row">
            <button className="btn btn-primary" style={{ flex: 1 }} disabled={pending} onClick={() => act(incoming === 'undo' ? { type: 'respondUndo', accept: true } : { type: 'respondDraw', accept: true })}>
              수락
            </button>
            <button className="btn btn-secondary" style={{ flex: 1 }} disabled={pending} onClick={() => act(incoming === 'undo' ? { type: 'respondUndo', accept: false } : { type: 'respondDraw', accept: false })}>
              거절
            </button>
          </div>
        </Sheet>
      )}
      {confirm === 'resign' && (
        <ConfirmSheet title="기권할까요?" body="기권하면 이 판은 상대가 이겨요." confirm="기권하기" danger onConfirm={() => act({ type: 'resign' })} onClose={() => setConfirm(null)} />
      )}
      {confirm === 'draw' && (
        <ConfirmSheet title="무승부를 제안할까요?" confirm="제안하기" onConfirm={() => act({ type: 'offerDraw' })} onClose={() => setConfirm(null)} />
      )}
    </div>
  );
}

function PlayerBar({ view: v, color, players, deadline, me }: { view: OmokView; color: Color; players: Record<string, PublicUser>; deadline: number | null; me: string | null }) {
  const id = v.players[color];
  const u = players[id] ?? { id, nickname: '알 수 없음', avatar: null, kind: 'guest' as const };
  const active = v.phase === 'playing' && v.turn === color;
  const now = useServerNow(500);
  const tc = v.timeControl;
  let clock: React.ReactNode = null;
  if (tc.kind === 'fischer') {
    const ms = Math.max(0, v.remainingMs[color] - (active ? now - v.turnStartedAt : 0));
    const s = Math.ceil(ms / 1000);
    clock = (
      <span style={{ fontVariantNumeric: 'tabular-nums', fontWeight: 700, fontSize: '1.15rem', color: active && s <= 10 ? 'var(--danger)' : undefined }}>
        {Math.floor(s / 60)}:{String(s % 60).padStart(2, '0')}
      </span>
    );
  } else if (active) {
    const total = tc.kind === 'perMove' ? tc.perMoveSec * 1000 : 300_000;
    clock = <TurnTimer deadline={deadline} totalMs={total} mine={id === me} />;
  }
  return (
    <div
      className="card row"
      style={{ padding: '8px 12px', gap: 10, border: `3px solid ${active ? 'var(--primary)' : 'transparent'}`, transition: 'border-color 0.2s' }}
    >
      <svg width={28} height={28} viewBox="-1 -1 2 2" aria-hidden>
        <Stone color={color} cx={0} cy={0} r={0.9} />
      </svg>
      <Avatar user={u} size={32} />
      <div style={{ flex: 1, minWidth: 0 }}>
        <div style={{ fontWeight: 700, whiteSpace: 'nowrap', overflow: 'hidden', textOverflow: 'ellipsis' }}>
          {u.nickname}
          {id === me && <span className="muted small"> (나)</span>}
        </div>
        <div className="muted small">{COLOR_KO[color]}{active ? ' · 두는 중' : ''}</div>
      </div>
      {clock}
    </div>
  );
}

function statusText(v: OmokView, me: string | null, players: Record<string, PublicUser>): string {
  if (v.phase === 'finished') return v.result?.summary ?? '게임이 끝났어요';
  if (v.myColor && v.undo.pending && v.undo.pending.by !== v.myColor) return '상대가 무르기를 요청했어요';
  if (v.myColor && v.draw.pendingBy && v.draw.pendingBy !== v.myColor) return '상대가 무승부를 제안했어요';
  if (v.myColor === v.turn) {
    if (v.moveCount === 0 && v.firstMoveCenter) return '내 차례예요. 첫 수는 가운데에 둬요';
    return `내 차례예요 (${COLOR_KO[v.turn]}). 놓을 곳을 눌러 주세요`;
  }
  const nick = players[v.players[v.turn]]?.nickname ?? COLOR_KO[v.turn];
  return v.myColor ? `${nick}님이 생각 중이에요…` : `${nick}님(${COLOR_KO[v.turn]}) 차례예요`;
}

// ---------------------------------------------------------------- options

function Seg<T extends string | number>({ value, options, onChange }: { value: T; options: [T, string][]; onChange: (v: T) => void }) {
  return (
    <div className="segmented">
      {options.map(([k, l]) => (
        <button key={String(k)} type="button" aria-pressed={value === k} onClick={() => onChange(k)}>
          {l}
        </button>
      ))}
    </div>
  );
}

const TIME_PRESETS: [string, string, Partial<OmokOptions['timeControl']>][] = [
  ['pm10', '한 수 10초', { kind: 'perMove', perMoveSec: 10 }],
  ['pm20', '한 수 20초', { kind: 'perMove', perMoveSec: 20 }],
  ['pm30', '한 수 30초', { kind: 'perMove', perMoveSec: 30 }],
  ['pm60', '한 수 60초', { kind: 'perMove', perMoveSec: 60 }],
  ['f3', '3분 + 2초', { kind: 'fischer', baseSec: 180, incSec: 2 }],
  ['f5', '5분 + 3초', { kind: 'fischer', baseSec: 300, incSec: 3 }],
  ['f10', '10분 + 5초', { kind: 'fischer', baseSec: 600, incSec: 5 }],
  ['none', '시간 제한 없음', { kind: 'none' }],
];

function timeKey(tc: OmokOptions['timeControl']): string {
  if (tc.kind === 'none') return 'none';
  if (tc.kind === 'perMove') return `pm${tc.perMoveSec}`;
  return `f${Math.round(tc.baseSec / 60)}`;
}

function Options({ value: o, onChange }: OptionsProps<OmokOptions>) {
  const [more, setMore] = useState(false);
  const set = (patch: Partial<OmokOptions>) => onChange({ ...o, ...patch });
  return (
    <div className="stack" style={{ gap: 16 }}>
      <div className="stack" style={{ gap: 6 }}>
        <strong>규칙</strong>
        <Seg value={o.ruleSet} options={[['korean', '한국식(쌍삼 금지)'], ['renju', '렌주룰'], ['free', '자유룰']]} onChange={(ruleSet) => set({ ruleSet })} />
      </div>
      <div className="stack" style={{ gap: 6 }}>
        <strong>시간</strong>
        <Seg
          value={timeKey(o.timeControl)}
          options={[
            ...TIME_PRESETS.map(([k, l]) => [k, l] as [string, string]),
            ...(TIME_PRESETS.some((p) => p[0] === timeKey(o.timeControl)) ? [] : [[timeKey(o.timeControl), `${timeLabel(o.timeControl)}(관리자 설정)`] as [string, string]]),
          ]}
          onChange={(k) => {
            const preset = TIME_PRESETS.find((p) => p[0] === k);
            if (preset) set({ timeControl: { ...o.timeControl, ...preset[2] } });
          }}
        />
      </div>
      <div className="stack" style={{ gap: 6 }}>
        <strong>흑(먼저 두는 쪽)</strong>
        <Seg
          value={o.colorAssignment}
          options={[['random', '무작위'], ['hostBlack', '방장이 흑'], ['hostWhite', '방장이 백'], ['alternate', '판마다 번갈아']]}
          onChange={(colorAssignment) => set({ colorAssignment })}
        />
      </div>
      <button type="button" className="btn btn-ghost" onClick={() => setMore(!more)} aria-expanded={more}>
        {more ? '▲ 자세한 설정 닫기' : '▼ 자세한 설정'}
      </button>
      {more && (
        <>
          <div className="stack" style={{ gap: 6 }}>
            <strong>판 크기</strong>
            <Seg value={o.boardSize} options={[[15, '15줄'], [19, '19줄']]} onChange={(boardSize) => set({ boardSize })} />
          </div>
          {o.ruleSet === 'free' && (
            <div className="stack" style={{ gap: 6 }}>
              <strong>자유룰 승리</strong>
              <Seg value={o.freeWin} options={[['fivePlus', '5목 이상'], ['exactFive', '정확히 5목']]} onChange={(freeWin) => set({ freeWin })} />
            </div>
          )}
          <div className="stack" style={{ gap: 6 }}>
            <strong>무르기</strong>
            <Seg value={o.undo} options={[['off', '안 씀'], ['1', '1번'], ['3', '3번'], ['unlimited', '무제한']]} onChange={(undo) => set({ undo })} />
          </div>
          {o.timeControl.kind === 'perMove' && (
            <div className="stack" style={{ gap: 6 }}>
              <strong>시간이 다 되면</strong>
              <Seg value={o.timeoutPolicy} options={[['autoMove', '자동으로 두기'], ['lose', '시간패']]} onChange={(timeoutPolicy) => set({ timeoutPolicy })} />
            </div>
          )}
          <div className="stack" style={{ gap: 6 }}>
            <strong>첫 수 가운데</strong>
            <Seg value={o.firstMoveCenter} options={[['auto', '렌주만'], ['on', '항상'], ['off', '안 함']]} onChange={(firstMoveCenter) => set({ firstMoveCenter })} />
          </div>
          <div className="stack" style={{ gap: 6 }}>
            <strong>도움 표시</strong>
            <Seg value={o.showForbidden ? 'on' : 'off'} options={[['on', '금수 자리 표시'], ['off', '금수 표시 안 함']]} onChange={(k) => set({ showForbidden: k === 'on' })} />
            <Seg value={o.hints} options={[['warn', '위험한 자리 알려 주기'], ['off', '알려 주지 않기']]} onChange={(hints) => set({ hints })} />
            <Seg value={o.drawOffer ? 'on' : 'off'} options={[['on', '무승부 제안 허용'], ['off', '무승부 제안 안 함']]} onChange={(k) => set({ drawOffer: k === 'on' })} />
          </div>
        </>
      )}
    </div>
  );
}

function timeLabel(tc: OmokOptions['timeControl']): string {
  if (tc.kind === 'none') return '시간 제한 없음';
  if (tc.kind === 'perMove') return `한 수 ${tc.perMoveSec}초`;
  const m = Math.floor(tc.baseSec / 60);
  const sec = tc.baseSec % 60;
  return `${m}분${sec ? ` ${sec}초` : ''} + ${tc.incSec}초`;
}

function optionsSummary(o: OmokOptions): string {
  const t = timeLabel(o.timeControl);
  return [RULE_KO[o.ruleSet], `${o.boardSize}줄`, t].join(' · ');
}

function Rules({ options }: { options?: OmokOptions }) {
  const rule = options?.ruleSet ?? 'korean';
  return (
    <div className="stack">
      <p>흑과 백이 번갈아 한 수씩 판의 빈 교차점에 돌을 놓아요. 가로, 세로, 대각선 중 한 줄로 내 돌 <strong>5개</strong>를 먼저 이으면 이겨요. 흑이 먼저 둬요.</p>
      {rule === 'korean' && (
        <p>
          <strong>한국식</strong>: 흑과 백 모두 <strong>쌍삼(열린 3을 두 개 동시에 만드는 수)</strong>을 둘 수 없어요. 6개 이상 이어지면 이긴 것이 아니에요.
        </p>
      )}
      {rule === 'renju' && (
        <p>
          <strong>렌주룰</strong>: 흑만 쌍삼, 사사(4를 두 개 동시에), 6목 이상을 둘 수 없어요. 백은 제한이 없고 6목 이상도 이겨요. 첫 수는 가운데에 둬요.
        </p>
      )}
      {rule === 'free' && (
        <p>
          <strong>자유룰</strong>: 금지된 수가 없어요. 설정에 따라 5개 이상이면 이기거나, 딱 5개일 때만 이겨요.
        </p>
      )}
      <p>둘 수 없는 자리는 판에 빨간 ×로 표시돼요. 상대가 곧 이길 수 있는 자리는 빨간 동그라미, 위험한 자리는 노란 점선으로 알려 줘요(설정에서 끌 수 있어요).</p>
      <p>휴대폰에서는 한 번 누르면 미리 보기 돌이 놓이고, 같은 곳을 한 번 더 누르거나 아래 [두기] 버튼을 누르면 확정돼요.</p>
    </div>
  );
}

const ui: GameUI<OmokView, OmokOptions> = {
  Board: OmokBoard,
  statusText,
  isMyTurn: (v, me) => v.phase === 'playing' && !!v.myColor && v.players[v.turn] === me,
  Options,
  optionsSummary,
  Rules,
};

export default ui;