import type {
  DashboardRealtimeTradeTick,
  DashboardStockOrderBookResponse,
} from "@/features/trade/types/trade.types";
import {
  shouldUseAfterHoursSinglePriceTr,
  shouldUseExpectedExecutionTr,
  type DomesticKisSession,
} from "@/lib/kis/domestic-market-session";

const REALTIME_SIGN_NEGATIVE = new Set(["4", "5"]);
const EXECUTED_REALTIME_TRADE_TR_IDS = new Set([
  "H0STCNT0",
  "H0STOUP0",
  "H0UNCNT0",
  "H0NXCNT0",
]);
const EXPECTED_REALTIME_TRADE_TR_IDS = new Set([
  "H0STANC0",
  "H0STOAC0",
  "H0UNANC0",
  "H0NXANC0",
]);

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,
  executionClassCode: 21,
} as const;

const TRADE_TR_ID = "H0STCNT0";
const TRADE_TR_ID_EXPECTED = "H0STANC0";
const TRADE_TR_ID_OVERTIME = "H0STOUP0";
const TRADE_TR_ID_OVERTIME_EXPECTED = "H0STOAC0";
const TRADE_TR_ID_TOTAL = "H0UNCNT0";
const TRADE_TR_ID_TOTAL_EXPECTED = "H0UNANC0";
const ORDERBOOK_TR_ID = "H0STASP0";
const ORDERBOOK_TR_ID_OVERTIME = "H0STOAA0";
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[];

  const receivedTrId = parts[1];
  const isExecutedTick = EXECUTED_REALTIME_TRADE_TR_IDS.has(receivedTrId);
  const isExpectedTick = EXPECTED_REALTIME_TRADE_TR_IDS.has(receivedTrId);

  if (!isExecutedTick || isExpectedTick) {
    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 normalizedExpected = normalizeDomesticSymbol(expectedSymbol);
  const ticks: DashboardRealtimeTradeTick[] = [];

  for (let index = 0; index < parsedCount; index++) {
    const base = index * fieldsPerTick;
    const symbol = readString(values, base + TICK_FIELD_INDEX.symbol);
    const normalizedSymbol = normalizeDomesticSymbol(symbol);
    if (normalizedSymbol !== normalizedExpected) {
      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: normalizedExpected,
      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,
      ),
      executionClassCode: readString(
        values,
        base + TICK_FIELD_INDEX.executionClassCode,
      ),
      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 장 구간/시장별 누락을 줄이기 위해 TR ID를 우선순위 배열로 반환합니다.
 */
export function resolveTradeTrIds(
  env: "real" | "mock",
  session: DomesticKisSession,
) {
  if (env === "mock") return [TRADE_TR_ID];

  if (shouldUseAfterHoursSinglePriceTr(session)) {
    return uniqueTrIds([
      TRADE_TR_ID_OVERTIME,
      TRADE_TR_ID_OVERTIME_EXPECTED,
      TRADE_TR_ID_TOTAL,
      TRADE_TR_ID_TOTAL_EXPECTED,
    ]);
  }

  if (shouldUseExpectedExecutionTr(session)) {
    return uniqueTrIds([
      TRADE_TR_ID_EXPECTED,
      TRADE_TR_ID_TOTAL_EXPECTED,
      TRADE_TR_ID,
      TRADE_TR_ID_TOTAL,
    ]);
  }

  if (session === "afterCloseFixedPrice") {
    return uniqueTrIds([
      TRADE_TR_ID,
      TRADE_TR_ID_TOTAL,
      TRADE_TR_ID_OVERTIME,
      TRADE_TR_ID_OVERTIME_EXPECTED,
      TRADE_TR_ID_TOTAL_EXPECTED,
    ]);
  }

  return uniqueTrIds([TRADE_TR_ID, TRADE_TR_ID_TOTAL]);
}

/**
 * @description 장 구간별 호가 TR ID 후보를 우선순위 배열로 반환합니다.
 */
export function resolveOrderBookTrIds(
  env: "real" | "mock",
  session: DomesticKisSession,
) {
  if (env === "mock") return [ORDERBOOK_TR_ID];

  if (shouldUseAfterHoursSinglePriceTr(session)) {
    return uniqueTrIds([ORDERBOOK_TR_ID_OVERTIME, ORDERBOOK_TR_ID]);
  }

  if (session === "afterCloseFixedPrice") {
    return uniqueTrIds([ORDERBOOK_TR_ID, ORDERBOOK_TR_ID_OVERTIME]);
  }

  return uniqueTrIds([ORDERBOOK_TR_ID]);
}

/**
 * @description 호가 패킷이 실제 표시 가능한 값(호가/잔량/총잔량)을 포함하는지 확인합니다.
 */
export function hasMeaningfulOrderBookPayload(
  data: DashboardStockOrderBookResponse,
) {
  const hasLevelData = data.levels.some(
    (level) =>
      level.askPrice > 0 ||
      level.bidPrice > 0 ||
      level.askSize > 0 ||
      level.bidSize > 0,
  );

  const hasSummaryData =
    data.totalAskSize > 0 ||
    data.totalBidSize > 0 ||
    (data.anticipatedPrice ?? 0) > 0 ||
    (data.accumulatedVolume ?? 0) > 0;

  return hasLevelData || hasSummaryData;
}

/**
 * @description KIS 실시간 호가(H0STASP0/H0UNASP0/H0STOAA0)를 OrderBook 구조로 파싱합니다.
 */
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("^");
  // 시간외(H0STOAA0)는 문서 버전에 따라 9레벨/10레벨이 혼재할 수 있어
  // payload 길이로 레벨 수를 동적으로 판별합니다.
  const levelCount = trId === "H0STOAA0" ? (values.length >= 56 ? 10 : 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 overtimeTotalAskIndex = totalBidIndex + 1;
  const overtimeTotalBidIndex = overtimeTotalAskIndex + 1;
  const anticipatedPriceIndex = overtimeTotalBidIndex + 1;
  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),
  }));

  const regularTotalAskSize = readNumber(values, totalAskIndex);
  const regularTotalBidSize = readNumber(values, totalBidIndex);
  const overtimeTotalAskSize = readNumber(values, overtimeTotalAskIndex);
  const overtimeTotalBidSize = readNumber(values, overtimeTotalBidIndex);

  return {
    symbol: normalizedExpected,
    // 장후 시간외에서는 일반 총잔량이 0이고 OVTM 총잔량만 채워지는 경우가 있습니다.
    totalAskSize:
      regularTotalAskSize > 0 ? regularTotalAskSize : overtimeTotalAskSize,
    totalBidSize:
      regularTotalBidSize > 0 ? regularTotalBidSize : overtimeTotalBidSize,
    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.
 */
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;
}

function uniqueTrIds(ids: string[]) {
  return [...new Set(ids)];
}