import type {
  DashboardRealtimeTradeTick,
  DashboardStockOrderBookResponse,
} from "@/features/trade/types/trade.types";

const REALTIME_SIGN_NEGATIVE = new Set(["4", "5"]);
const ALLOWED_REALTIME_TRADE_TR_IDS = new Set([
  "H0STCNT0",
  "H0STANC0",
  "H0STOUP0",
  "H0STOAC0",
]);

const TICK_FIELD_INDEX = {
  symbol: 0,
  tickTime: 1,
  price: 2,
  sign: 3,
  change: 4,
  changeRate: 5,
  open: 7,
  high: 8,
  low: 9,
  askPrice1: 10,
  bidPrice1: 11,
  tradeVolume: 12,
  accumulatedVolume: 13,
  sellExecutionCount: 15,
  buyExecutionCount: 16,
  netBuyExecutionCount: 17,
  tradeStrength: 18,
} as const;

/**
 * @description KIS 실시간 구독/해제 소켓 메시지를 생성합니다.
 * @see features/trade/hooks/useKisTradeWebSocket.ts 구독/해제 요청 payload 생성에 사용됩니다.
 */
export function buildKisRealtimeMessage(
  approvalKey: string,
  symbol: string,
  trId: string,
  trType: "1" | "2",
) {
  return {
    header: {
      approval_key: approvalKey,
      custtype: "P",
      tr_type: trType,
      "content-type": "utf-8",
    },
    body: {
      input: {
        tr_id: trId,
        tr_key: symbol,
      },
    },
  };
}

/**
 * @description 실시간 체결 스트림(raw)을 배열 단위로 파싱합니다.
 * - 배치 전송(복수 체결) 데이터를 모두 추출합니다.
 * - 종목 불일치 또는 가격 0 이하 데이터는 제외합니다.
 * @see features/trade/hooks/useKisTradeWebSocket.ts onmessage 이벤트에서 체결 패킷 파싱에 사용됩니다.
 */
export function parseKisRealtimeTickBatch(raw: string, expectedSymbol: string) {
  if (!/^([01])\|/.test(raw)) return [] as DashboardRealtimeTradeTick[];

  const parts = raw.split("|");
  if (parts.length < 4) return [] as DashboardRealtimeTradeTick[];

  // TR ID check: regular tick / expected tick / after-hours tick.
  const receivedTrId = parts[1];
  if (!ALLOWED_REALTIME_TRADE_TR_IDS.has(receivedTrId)) {
    return [] as DashboardRealtimeTradeTick[];
  }

  // if (parts[1] !== expectedTrId) return [] as DashboardRealtimeTradeTick[];

  const tickCount = Number(parts[2] ?? "1");
  const values = parts[3].split("^");
  if (values.length === 0) return [] as DashboardRealtimeTradeTick[];

  const parsedCount =
    Number.isInteger(tickCount) && tickCount > 0 ? tickCount : 1;
  const fieldsPerTick = Math.floor(values.length / parsedCount);
  if (fieldsPerTick <= TICK_FIELD_INDEX.tradeStrength) {
    return [] as DashboardRealtimeTradeTick[];
  }

  const ticks: DashboardRealtimeTradeTick[] = [];

  for (let index = 0; index < parsedCount; index++) {
    const base = index * fieldsPerTick;
    const symbol = readString(values, base + TICK_FIELD_INDEX.symbol);
    if (symbol !== expectedSymbol) {
      if (symbol.trim() !== expectedSymbol.trim()) {
        console.warn(
          `[KisRealtime] Symbol mismatch: received '${symbol}', expected '${expectedSymbol}'`,
        );
        continue;
      }
    }

    const price = readNumber(values, base + TICK_FIELD_INDEX.price);
    if (!Number.isFinite(price) || price <= 0) continue;

    const sign = readString(values, base + TICK_FIELD_INDEX.sign);
    const rawChange = readNumber(values, base + TICK_FIELD_INDEX.change);
    const rawChangeRate = readNumber(
      values,
      base + TICK_FIELD_INDEX.changeRate,
    );
    const change = REALTIME_SIGN_NEGATIVE.has(sign)
      ? -Math.abs(rawChange)
      : rawChange;
    const changeRate = REALTIME_SIGN_NEGATIVE.has(sign)
      ? -Math.abs(rawChangeRate)
      : rawChangeRate;

    ticks.push({
      symbol,
      tickTime: readString(values, base + TICK_FIELD_INDEX.tickTime),
      price,
      change,
      changeRate,
      tradeVolume: readNumber(values, base + TICK_FIELD_INDEX.tradeVolume),
      accumulatedVolume: readNumber(
        values,
        base + TICK_FIELD_INDEX.accumulatedVolume,
      ),
      tradeStrength: readNumber(values, base + TICK_FIELD_INDEX.tradeStrength),
      askPrice1: readNumber(values, base + TICK_FIELD_INDEX.askPrice1),
      bidPrice1: readNumber(values, base + TICK_FIELD_INDEX.bidPrice1),
      sellExecutionCount: readNumber(
        values,
        base + TICK_FIELD_INDEX.sellExecutionCount,
      ),
      buyExecutionCount: readNumber(
        values,
        base + TICK_FIELD_INDEX.buyExecutionCount,
      ),
      netBuyExecutionCount: readNumber(
        values,
        base + TICK_FIELD_INDEX.netBuyExecutionCount,
      ),
      open: readNumber(values, base + TICK_FIELD_INDEX.open),
      high: readNumber(values, base + TICK_FIELD_INDEX.high),
      low: readNumber(values, base + TICK_FIELD_INDEX.low),
    });
  }

  return ticks;
}

/**
 * @description KIS 실시간 호가(H0STASP0/H0UNASP0/H0STOAA0)를 OrderBook 구조로 파싱합니다.
 * @see features/trade/hooks/useKisTradeWebSocket.ts onOrderBookMessage 콜백 데이터 생성에 사용됩니다.
 */
export function parseKisRealtimeOrderbook(
  raw: string,
  expectedSymbol: string,
): DashboardStockOrderBookResponse | null {
  if (!/^([01])\|/.test(raw)) return null;

  const parts = raw.split("|");
  if (parts.length < 4) return null;
  const trId = parts[1];
  if (trId !== "H0STASP0" && trId !== "H0UNASP0" && trId !== "H0STOAA0") {
    return null;
  }

  const values = parts[3].split("^");
  const levelCount = trId === "H0STOAA0" ? 9 : 10;

  const symbol = values[0]?.trim() ?? "";
  const normalizedSymbol = normalizeDomesticSymbol(symbol);
  const normalizedExpected = normalizeDomesticSymbol(expectedSymbol);
  if (normalizedSymbol !== normalizedExpected) return null;

  const askPriceStart = 3;
  const bidPriceStart = askPriceStart + levelCount;
  const askSizeStart = bidPriceStart + levelCount;
  const bidSizeStart = askSizeStart + levelCount;
  const totalAskIndex = bidSizeStart + levelCount;
  const totalBidIndex = totalAskIndex + 1;
  const anticipatedPriceIndex = totalBidIndex + 3;
  const anticipatedVolumeIndex = anticipatedPriceIndex + 1;
  const anticipatedTotalVolumeIndex = anticipatedPriceIndex + 2;
  const anticipatedChangeIndex = anticipatedPriceIndex + 3;
  const anticipatedChangeSignIndex = anticipatedPriceIndex + 4;
  const anticipatedChangeRateIndex = anticipatedPriceIndex + 5;
  const accumulatedVolumeIndex = anticipatedPriceIndex + 6;
  const totalAskDeltaIndex = anticipatedPriceIndex + 7;
  const totalBidDeltaIndex = anticipatedPriceIndex + 8;
  const minFieldLength = totalBidDeltaIndex + 1;

  if (values.length < minFieldLength) return null;

  const realtimeLevels = Array.from({ length: levelCount }, (_, i) => ({
    askPrice: readNumber(values, askPriceStart + i),
    bidPrice: readNumber(values, bidPriceStart + i),
    askSize: readNumber(values, askSizeStart + i),
    bidSize: readNumber(values, bidSizeStart + i),
  }));

  return {
    symbol: normalizedExpected,
    totalAskSize: readNumber(values, totalAskIndex),
    totalBidSize: readNumber(values, totalBidIndex),
    businessHour: readString(values, 1),
    hourClassCode: readString(values, 2),
    anticipatedPrice: readNumber(values, anticipatedPriceIndex),
    anticipatedVolume: readNumber(values, anticipatedVolumeIndex),
    anticipatedTotalVolume: readNumber(values, anticipatedTotalVolumeIndex),
    anticipatedChange: readNumber(values, anticipatedChangeIndex),
    anticipatedChangeSign: readString(values, anticipatedChangeSignIndex),
    anticipatedChangeRate: readNumber(values, anticipatedChangeRateIndex),
    accumulatedVolume: readNumber(values, accumulatedVolumeIndex),
    totalAskSizeDelta: readNumber(values, totalAskDeltaIndex),
    totalBidSizeDelta: readNumber(values, totalBidDeltaIndex),
    levels: realtimeLevels,
    source: "REALTIME",
    tradingEnv: "real",
    fetchedAt: new Date().toISOString(),
  };
}

/**
 * @description 국내 종목코드 비교를 위해 접두 문자를 제거하고 6자리 코드로 정규화합니다.
 * @see features/trade/utils/kis-realtime.utils.ts parseKisRealtimeOrderbook 종목 매칭 비교에 사용됩니다.
 */
function normalizeDomesticSymbol(value: string) {
  const trimmed = value.trim();
  const digits = trimmed.replace(/\D/g, "");

  if (digits.length >= 6) {
    return digits.slice(-6);
  }

  return trimmed;
}

function readString(values: string[], index: number) {
  return (values[index] ?? "").trim();
}

function readNumber(values: string[], index: number) {
  const raw = readString(values, index).replaceAll(",", "");
  const value = Number(raw);
  return Number.isFinite(value) ? value : 0;
}