"use client";

import { useMemo, useState } from "react";
import { MATCH, AI_PREDICTIONS, CROWD, LANDING_URL } from "@/lib/mockData";
import { outcomeLabel, pct } from "@/lib/format";
import type { Outcome, CrowdStats, ModelName } from "@/lib/types";

type Step = "pick" | "form" | "done";

const MODEL_COLOR: Record<ModelName, string> = {
  GPT: "var(--gpt)",
  Claude: "var(--claude)",
  Gemini: "var(--gemini)",
};
const MODEL_ICON: Record<ModelName, string> = {
  GPT: "/icons/gpt.png",
  Claude: "/icons/claude.jpg",
  Gemini: "/icons/gemini.jpeg",
};

export default function Arena() {
  const [outcome, setOutcome] = useState<Outcome | null>(null);
  const [scoreA, setScoreA] = useState(2);
  const [scoreB, setScoreB] = useState(1);
  const [step, setStep] = useState<Step>("pick");
  const [nickname, setNickname] = useState("");
  const [email, setEmail] = useState("");
  const [notify, setNotify] = useState(true);
  const [crowd, setCrowd] = useState<CrowdStats>(CROWD);
  const [copied, setCopied] = useState(false);

  const locked = Date.now() >= new Date(MATCH.lockAt).getTime();

  const matched = useMemo(() => {
    if (!outcome) return [];
    return AI_PREDICTIONS.filter((p) => p.outcome === outcome).map((p) => ({
      model: p.model,
      exact: p.scoreA === scoreA && p.scoreB === scoreB,
    }));
  }, [outcome, scoreA, scoreB]);

  const submitPick = () => {
    if (!outcome) return;
    setStep("form");
  };
  const confirmSubmit = () => {
    if (nickname.trim().length < 2) return;
    setCrowd((c) => ({
      ...c,
      total: c.total + 1,
      teamAWin: c.teamAWin + (outcome === "TEAM_A_WIN" ? 1 : 0),
      draw: c.draw + (outcome === "DRAW" ? 1 : 0),
      teamBWin: c.teamBWin + (outcome === "TEAM_B_WIN" ? 1 : 0),
    }));
    setStep("done");
  };

  const shareText = useMemo(() => {
    if (!outcome) return "";
    const me = `${MATCH.teamA.shortName} ${scoreA}-${scoreB} ${MATCH.teamB.shortName}`;
    const sameAI = matched.map((m) => m.model).join("·");
    return sameAI
      ? `나는 ${me}. ${sameAI}와 같은 선택! 너는? — TriplePick`
      : `나는 ${me}. AI 셋과 다 다른 선택! 너는? — TriplePick`;
  }, [outcome, scoreA, scoreB, matched]);

  const copyLink = async () => {
    try {
      await navigator.clipboard.writeText(`${shareText}\n${LANDING_URL}`);
      setCopied(true);
      setTimeout(() => setCopied(false), 1800);
    } catch {
      setCopied(false);
    }
  };
  const nativeShare = async () => {
    if (navigator.share) {
      try {
        await navigator.share({ text: shareText, url: LANDING_URL });
      } catch {
        /* cancelled */
      }
    } else copyLink();
  };

  return (
    <>
      {/* ===== 레이어드 화이트 시트 (002) ===== */}
      <section className="sheet mt-6 p-5 text-[var(--ink)]">
        <div className="mb-3 flex items-end gap-2">
          <h2 className="text-[22px] font-extrabold">AI의 예측</h2>
          <span className="mb-1.5 h-[4px] w-10 rounded bg-[var(--green)]" />
        </div>

        <div className="flex flex-col gap-3">
          {AI_PREDICTIONS.map((p) => (
            <div
              key={p.model}
              className="rounded-2xl border border-[var(--line-l)] bg-[var(--sheet-card)] p-4"
            >
              <div className="flex items-center gap-3">
                <img
                  src={MODEL_ICON[p.model]}
                  alt={p.model}
                  className="h-12 w-12 shrink-0 rounded-full object-cover"
                />
                <div className="min-w-0">
                  <div className="text-[20px] font-extrabold leading-none">
                    {p.model}
                  </div>
                  <div className="mt-1 text-[11px] font-semibold text-[var(--ink-muted)]">
                    Confidence
                  </div>
                </div>
                <div className="ml-auto flex shrink-0 items-center gap-3">
                  <div className="whitespace-nowrap font-mono text-[28px] font-extrabold tabular-nums">
                    {p.scoreA}&nbsp;-&nbsp;{p.scoreB}
                  </div>
                  <div className="w-11 text-right text-[18px] font-extrabold">
                    {p.confidencePct}%
                  </div>
                </div>
              </div>

              <div className="mt-2.5 h-2.5 w-full overflow-hidden rounded-full bg-[#eceee9]">
                <div
                  className="bar-anim h-full rounded-full"
                  style={{
                    width: `${p.confidencePct}%`,
                    background: MODEL_COLOR[p.model],
                  }}
                />
              </div>
              <p className="mt-2 text-[13px] leading-snug text-[var(--ink-muted)]">
                {p.reasonShort}
              </p>
            </div>
          ))}
        </div>

        {/* 당신의 선택 */}
        <div className="mt-5 flex items-center justify-between">
          <span className="text-[13px] font-bold text-[var(--ink-muted)]">
            Your Pick · 내 예측
          </span>
          <span className="text-[20px] font-extrabold">당신의 선택</span>
        </div>

        <div className="mt-3 grid grid-cols-3 gap-2">
          {(
            [
              ["TEAM_A_WIN", `${MATCH.teamA.shortName} 승`],
              ["DRAW", "무승부"],
              ["TEAM_B_WIN", `${MATCH.teamB.shortName} 승`],
            ] as [Outcome, string][]
          ).map(([val, label]) => (
            <button
              key={val}
              disabled={locked}
              onClick={() => setOutcome(val)}
              className={`rounded-xl border py-3.5 text-[16px] font-extrabold transition ${
                outcome === val
                  ? "border-transparent bg-[var(--mint)] text-[var(--mint-ink)]"
                  : "border-[var(--line-l)] bg-white text-[var(--ink-muted)]"
              }`}
            >
              {label}
            </button>
          ))}
        </div>

        <div className="mt-3 flex items-center justify-center gap-5 rounded-xl border border-[var(--line-l)] bg-white py-3">
          <Stepper label={MATCH.teamA.shortName} value={scoreA} onChange={setScoreA} disabled={locked} />
          <span className="text-[26px] font-extrabold text-[var(--ink-muted)]">:</span>
          <Stepper label={MATCH.teamB.shortName} value={scoreB} onChange={setScoreB} disabled={locked} />
        </div>
      </section>

      {/* ===== CTA 민트 #85FCA8 ===== */}
      {step === "pick" && (
        <button
          onClick={submitPick}
          disabled={!outcome || locked}
          className="btn-mint mt-5 w-full rounded-2xl py-5 text-[20px] font-extrabold transition active:scale-[0.99] disabled:opacity-40 disabled:shadow-none"
        >
          {locked ? "예측 마감" : "AI보다 잘 맞히기"}
        </button>
      )}

      {step === "form" && (
        <div className="mt-5 space-y-2.5 rounded-2xl border border-[var(--line-d)] bg-[var(--bg2)] p-4">
          <input
            value={nickname}
            onChange={(e) => setNickname(e.target.value)}
            maxLength={16}
            placeholder="닉네임 (2~16자)"
            className="w-full rounded-lg border border-[var(--line-d)] bg-[#0f1217] px-3 py-3 text-[15px] text-white outline-none focus:border-[var(--green)]"
          />
          <input
            value={email}
            onChange={(e) => setEmail(e.target.value)}
            placeholder="이메일 (선택 · 결과 알림)"
            className="w-full rounded-lg border border-[var(--line-d)] bg-[#0f1217] px-3 py-3 text-[15px] text-white outline-none focus:border-[var(--green)]"
          />
          <label className="flex items-center gap-2 text-[13px] text-[var(--ink-muted)]">
            <input type="checkbox" checked={notify} onChange={(e) => setNotify(e.target.checked)} className="accent-[var(--mint)]" />
            경기 결과 나오면 알려주세요 (AI 이겼는지 확인)
          </label>
          <button
            onClick={confirmSubmit}
            disabled={nickname.trim().length < 2}
            className="btn-mint w-full rounded-xl py-3.5 text-[17px] font-extrabold transition active:scale-[0.99] disabled:opacity-40 disabled:shadow-none"
          >
            제출하고 AI와 겨루기
          </button>
        </div>
      )}

      {step === "done" && outcome && (
        <div className="mt-5 rounded-2xl border border-[var(--green)]/50 bg-[var(--bg2)] p-5">
          <div className="text-[13px] text-[var(--ink-muted)]">내 예측</div>
          <div className="mt-1 text-[26px] font-extrabold">
            {MATCH.teamA.shortName} {scoreA}-{scoreB} {MATCH.teamB.shortName}
            <span className="ml-2 text-[16px] font-bold text-[var(--green)]">
              {outcomeLabel(MATCH, outcome)}
            </span>
          </div>
          <p className="mt-2 text-[14px] leading-relaxed text-white/80">
            {matched.length > 0 ? (
              <>
                당신은 <b>{matched.map((m) => m.model).join("·")}</b>와 같은
                선택입니다.{matched.some((m) => m.exact) ? " 스코어까지 일치! " : " "}
                나머지 AI는 생각이 다릅니다.
              </>
            ) : (
              <>당신은 AI 셋 모두와 다른 선택! 소신 픽 🔥</>
            )}
          </p>
          <div className="mt-4 grid grid-cols-2 gap-2.5">
            <button onClick={nativeShare} className="btn-mint rounded-xl py-3 text-[15px] font-bold active:scale-[0.99]">
              내 픽 자랑하기
            </button>
            <button onClick={copyLink} className="rounded-xl border border-[var(--line-d)] py-3 text-[15px] font-bold active:scale-[0.99]">
              {copied ? "복사됨 ✓" : "링크 복사"}
            </button>
          </div>
        </div>
      )}

      {/* ===== 골드 상금 (003) ===== */}
      <section className="gold-card mt-5 rounded-2xl p-5">
        <div className="flex items-center justify-between gap-3">
          <div className="min-w-0">
            <div className="flex items-center gap-1.5 text-[18px] font-extrabold text-[var(--gold-border)]">
              <span>₩1,000,000 Final Challenge</span>
              <span>★</span>
            </div>
            <p className="mt-1.5 text-[13px] leading-snug text-white/75">
              <b className="text-[var(--gold-border)]">NEW</b> 정확한 스코어까지
              맞히면 100만원 상금에 도전하세요
            </p>
          </div>
          <button className="gold-btn shrink-0 rounded-xl px-4 py-3.5 text-[14px] font-extrabold leading-tight active:scale-[0.98]">
            100만 원에
            <br />
            도전하기
          </button>
        </div>
      </section>

      {/* ===== Crowd Pick (003) ===== */}
      <section className="mt-6">
        <div className="mb-2.5 text-[20px] font-extrabold">
          Crowd Pick{" "}
          <span className="text-[14px] text-[var(--ink-muted)]">
            | 참여자들의 선택
          </span>
        </div>
        <div className="flex h-14 overflow-hidden rounded-2xl border border-[var(--line-d)]">
          <CrowdSeg flag="/icons/kor.png" value={pct(crowd.teamAWin, crowd.total)} tone="kor" />
          <CrowdSeg value={pct(crowd.draw, crowd.total)} tone="draw" />
          <CrowdSeg cze value={pct(crowd.teamBWin, crowd.total)} tone="cze" />
        </div>
        <div className="mt-1.5 text-right text-[11px] text-[var(--ink-muted)]">
          {crowd.total.toLocaleString()}명 참여
        </div>
      </section>
    </>
  );
}

function Stepper({
  label,
  value,
  onChange,
  disabled,
}: {
  label: string;
  value: number;
  onChange: (n: number) => void;
  disabled?: boolean;
}) {
  return (
    <div className="flex items-center gap-3">
      <StepBtn disabled={disabled || value <= 0} onClick={() => onChange(Math.max(0, value - 1))}>
        −
      </StepBtn>
      <div className="flex w-12 flex-col items-center">
        <span className="font-mono text-[32px] font-extrabold leading-none tabular-nums">
          {value}
        </span>
        <span className="mt-1 text-[11px] text-[var(--ink-muted)]">{label}</span>
      </div>
      <StepBtn disabled={disabled || value >= 9} onClick={() => onChange(Math.min(9, value + 1))}>
        +
      </StepBtn>
    </div>
  );
}

function StepBtn({
  children,
  onClick,
  disabled,
}: {
  children: React.ReactNode;
  onClick: () => void;
  disabled?: boolean;
}) {
  return (
    <button
      onClick={onClick}
      disabled={disabled}
      className="grid h-11 w-11 place-items-center rounded-xl border border-[var(--line-l)] bg-white text-[22px] font-bold leading-none text-[var(--ink)] active:scale-95 disabled:opacity-30"
    >
      {children}
    </button>
  );
}

function CrowdSeg({
  flag,
  cze,
  value,
  tone,
}: {
  flag?: string;
  cze?: boolean;
  value: number;
  tone: "kor" | "draw" | "cze";
}) {
  const bg =
    tone === "draw" ? "#2b313c" : tone === "kor" ? "rgba(62,224,138,0.22)" : "#222831";
  return (
    <div
      className="flex items-center justify-center gap-1.5 border-r border-[var(--line-d)] text-[16px] font-extrabold last:border-r-0"
      style={{ width: `${value}%`, background: bg, minWidth: 56 }}
    >
      {flag && <img src={flag} alt="KOR" className="h-4 w-6 rounded object-cover" />}
      {cze && (
        <svg viewBox="0 0 6 4" className="h-4 w-6 rounded" preserveAspectRatio="none">
          <rect width="6" height="2" y="0" fill="#fff" />
          <rect width="6" height="2" y="2" fill="#d7141a" />
          <polygon points="0,0 3,2 0,4" fill="#11457e" />
        </svg>
      )}
      <span>{value}%</span>
    </div>
  );
}