export interface KisRealtimeIndexTick {
  symbol: string; // 업종코드 (0001: KOSPI, 1001: KOSDAQ)
  price: number; // 현재가
  change: number; // 전일대비
  changeRate: number; // 전일대비율
  sign: string; // 대비부호
  time: string; // 체결시간
}

const INDEX_REALTIME_TR_ID = "H0UPCNT0";

const INDEX_FIELD_INDEX = {
  symbol: 0, // bstp_cls_code
  time: 1, // bsop_hour
  price: 2, // prpr_nmix
  sign: 3, // prdy_vrss_sign
  change: 4, // bstp_nmix_prdy_vrss
  accumulatedVolume: 5, // acml_vol
  accumulatedAmount: 6, // acml_tr_pbmn
  changeRate: 9, // prdy_ctrt
} as const;

export function parseKisRealtimeIndexTick(
  raw: string,
): KisRealtimeIndexTick | null {
  // Format: 0|H0UPCNT0|001|0001^123456^...
  if (!/^([01])\|/.test(raw)) return null;

  const parts = raw.split("|");
  if (parts.length < 4) return null;

  // Check TR ID
  if (parts[1] !== INDEX_REALTIME_TR_ID) {
    return null;
  }

  const values = parts[3].split("^");
  if (values.length < 10) return null; // Ensure minimum fields exist

  const symbol = values[INDEX_FIELD_INDEX.symbol];
  const price = parseFloat(values[INDEX_FIELD_INDEX.price]);
  const sign = values[INDEX_FIELD_INDEX.sign];
  const changeRaw = parseFloat(values[INDEX_FIELD_INDEX.change]);
  const changeRateRaw = parseFloat(values[INDEX_FIELD_INDEX.changeRate]);

  // Adjust sign for negative values if necessary (usually API sends absolute values for change)
  const isNegative = sign === "5" || sign === "4"; // 5: 하락, 4: 하한

  const change = isNegative ? -Math.abs(changeRaw) : Math.abs(changeRaw);
  const changeRate = isNegative
    ? -Math.abs(changeRateRaw)
    : Math.abs(changeRateRaw);

  return {
    symbol,
    time: values[INDEX_FIELD_INDEX.time],
    price,
    change,
    changeRate,
    sign,
  };
}