import { useEffect, useRef, useState } from "react";
import {
  type KisRuntimeCredentials,
  useKisRuntimeStore,
} from "@/features/dashboard/store/use-kis-runtime-store";
import type {
  DashboardRealtimeTradeTick,
  DashboardStockOrderBookResponse,
  StockCandlePoint,
} from "@/features/dashboard/types/dashboard.types";
import {
  appendRealtimeTick,
  buildKisRealtimeMessage,
  formatRealtimeTickTime,
  parseKisRealtimeOrderbook,
  parseKisRealtimeTickBatch,
  toTickOrderValue,
} from "@/features/dashboard/utils/kis-realtime.utils";

// ─── TR ID 상수 ─────────────────────────────────────────
const TRADE_TR_ID = "H0STCNT0"; // 체결 (실전/모의 공통)
const TRADE_TR_ID_OVERTIME = "H0STOUP0"; // 시간외 단일가
const ORDERBOOK_TR_ID = "H0STASP0"; // 호가 (정규장)
const ORDERBOOK_TR_ID_OVERTIME = "H0STOAA0"; // 호가 (시간외)

const MAX_TRADE_TICKS = 10;

// ─── 시간대별 TR ID 선택 ────────────────────────────────

function isOvertimeHours() {
  const now = new Date();
  const t = now.getHours() * 100 + now.getMinutes();
  return t >= 1600 && t < 1800;
}

function resolveTradeTrId(env: KisRuntimeCredentials["tradingEnv"]) {
  if (env === "mock") return TRADE_TR_ID;
  return isOvertimeHours() ? TRADE_TR_ID_OVERTIME : TRADE_TR_ID;
}

function resolveOrderBookTrId() {
  return isOvertimeHours() ? ORDERBOOK_TR_ID_OVERTIME : ORDERBOOK_TR_ID;
}

// ─── 메인 훅 ────────────────────────────────────────────

/**
 * 통합 실시간 웹소켓 훅 — 체결(H0STCNT0) + 호가(H0STASP0)를 단일 WS로 수신합니다.
 *
 * @param symbol 종목코드
 * @param credentials KIS 인증 정보
 * @param isVerified 인증 완료 여부
 * @param onTick 체결 콜백 (StockHeader 갱신용)
 * @param options.orderBookSymbol 호가 구독 종목코드
 * @param options.onOrderBookMessage 호가 수신 콜백
 */
export function useKisTradeWebSocket(
  symbol: string | undefined,
  credentials: KisRuntimeCredentials | null,
  isVerified: boolean,
  onTick?: (tick: DashboardRealtimeTradeTick) => void,
  options?: {
    orderBookSymbol?: string;
    onOrderBookMessage?: (data: DashboardStockOrderBookResponse) => void;
  },
) {
  const [latestTick, setLatestTick] =
    useState<DashboardRealtimeTradeTick | null>(null);
  const [realtimeCandles, setRealtimeCandles] = useState<StockCandlePoint[]>(
    [],
  );
  const [recentTradeTicks, setRecentTradeTicks] = useState<
    DashboardRealtimeTradeTick[]
  >([]);
  const [isConnected, setIsConnected] = useState(false);
  const [error, setError] = useState<string | null>(null);
  const [lastTickAt, setLastTickAt] = useState<number | null>(null);

  const socketRef = useRef<WebSocket | null>(null);
  const approvalKeyRef = useRef<string | null>(null);
  const lastTickOrderRef = useRef<number>(-1);
  const seenTickRef = useRef<Set<string>>(new Set());

  const trId = credentials ? resolveTradeTrId(credentials.tradingEnv) : null;
  const obSymbol = options?.orderBookSymbol;
  const onOrderBookMsg = options?.onOrderBookMessage;
  const obTrId = obSymbol ? resolveOrderBookTrId() : null;

  // 8초간 데이터 없을 시 안내 메시지
  useEffect(() => {
    if (!isConnected || lastTickAt) return;

    const timer = window.setTimeout(() => {
      setError(
        "실시간 연결은 되었지만 체결 데이터가 없습니다. 장중(09:00~15:30)인지 확인해 주세요.",
      );
    }, 8000);

    return () => window.clearTimeout(timer);
  }, [isConnected, lastTickAt]);

  // ─── 웹소켓 연결 ─────────────────────────────────────
  useEffect(() => {
    setLatestTick(null);
    setRealtimeCandles([]);
    setRecentTradeTicks([]);
    setError(null);
    seenTickRef.current.clear();

    if (!symbol || !isVerified || !credentials) {
      socketRef.current?.close();
      socketRef.current = null;
      approvalKeyRef.current = null;
      setIsConnected(false);
      return;
    }

    let disposed = false;
    let socket: WebSocket | null = null;
    const currentTrId = resolveTradeTrId(credentials.tradingEnv);

    const connect = async () => {
      try {
        setError(null);
        setIsConnected(false);

        const approvalKey = await useKisRuntimeStore
          .getState()
          .getOrFetchApprovalKey();

        if (!approvalKey) throw new Error("웹소켓 승인키 발급에 실패했습니다.");
        if (disposed) return;

        approvalKeyRef.current = approvalKey;

        const wsBase =
          process.env.NEXT_PUBLIC_KIS_WS_URL ||
          "ws://ops.koreainvestment.com:21000";
        socket = new WebSocket(`${wsBase}/tryitout/${currentTrId}`);
        socketRef.current = socket;

        // ── onopen: 체결 + 호가 구독 ──
        socket.onopen = () => {
          if (disposed || !approvalKeyRef.current) return;

          socket?.send(
            JSON.stringify(
              buildKisRealtimeMessage(
                approvalKeyRef.current,
                symbol,
                currentTrId,
                "1",
              ),
            ),
          );

          if (obSymbol && obTrId) {
            socket?.send(
              JSON.stringify(
                buildKisRealtimeMessage(
                  approvalKeyRef.current,
                  obSymbol,
                  obTrId,
                  "1",
                ),
              ),
            );
          }

          setIsConnected(true);
        };

        // ── onmessage: TR ID 기반 분기 ──
        socket.onmessage = (event) => {
          if (disposed || typeof event.data !== "string") return;

          // 호가 메시지 확인
          if (obSymbol && onOrderBookMsg) {
            const ob = parseKisRealtimeOrderbook(event.data, obSymbol);
            if (ob) {
              if (credentials) ob.tradingEnv = credentials.tradingEnv;
              onOrderBookMsg(ob);
              return;
            }
          }

          // 체결 메시지 파싱
          const ticks = parseKisRealtimeTickBatch(event.data, symbol);
          if (ticks.length === 0) return;

          // 중복 제거 (TradeTape용)
          const meaningful = ticks.filter((t) => t.tradeVolume > 0);
          const deduped = meaningful.filter((t) => {
            const key = `${t.tickTime}-${t.price}-${t.tradeVolume}`;
            if (seenTickRef.current.has(key)) return false;
            seenTickRef.current.add(key);
            return true;
          });

          // 최신 틱 → Header
          const latest = ticks[ticks.length - 1];
          setLatestTick(latest);

          // 캔들 → Chart
          const order = toTickOrderValue(latest.tickTime);
          if (order > 0 && lastTickOrderRef.current <= order) {
            lastTickOrderRef.current = order;
            setRealtimeCandles((prev) =>
              appendRealtimeTick(prev, {
                time: formatRealtimeTickTime(latest.tickTime),
                price: latest.price,
              }),
            );
          }

          // 체결 테이프
          if (deduped.length > 0) {
            setRecentTradeTicks((prev) =>
              [...deduped.reverse(), ...prev].slice(0, MAX_TRADE_TICKS),
            );
          }

          setError(null);
          setLastTickAt(Date.now());
          onTick?.(latest);
        };

        socket.onerror = () => {
          if (!disposed) setIsConnected(false);
        };
        socket.onclose = () => {
          if (!disposed) setIsConnected(false);
        };
      } catch (err) {
        if (disposed) return;
        setError(
          err instanceof Error
            ? err.message
            : "실시간 웹소켓 초기화 중 오류가 발생했습니다.",
        );
        setIsConnected(false);
      }
    };

    void connect();
    const seenRef = seenTickRef.current;

    // ── cleanup: 구독 해제 ──
    return () => {
      disposed = true;
      setIsConnected(false);

      const key = approvalKeyRef.current;
      if (socket?.readyState === WebSocket.OPEN && key) {
        socket.send(
          JSON.stringify(
            buildKisRealtimeMessage(key, symbol, currentTrId, "2"),
          ),
        );
        if (obSymbol && obTrId) {
          socket.send(
            JSON.stringify(buildKisRealtimeMessage(key, obSymbol, obTrId, "2")),
          );
        }
      }

      socket?.close();
      if (socketRef.current === socket) socketRef.current = null;
      approvalKeyRef.current = null;
      seenRef.clear();
    };
  }, [
    isVerified,
    symbol,
    credentials,
    onTick,
    obSymbol,
    obTrId,
    onOrderBookMsg,
  ]);

  return {
    latestTick,
    realtimeCandles,
    recentTradeTicks,
    isConnected,
    error,
    lastTickAt,
    realtimeTrId: trId ?? TRADE_TR_ID,
  };
}