---

function realtimeConvolution(
  timeframe: Timeframes,
  data: Candle,
  currentState: RealtimeState,
): {
  candle: Candle | undefined;
  state: RealtimeState;
} {
  const timeframeSeconds = getTimeframeSeconds(timeframe);
  const { previousTime, sessionStart } = currentState;

  if (
    previousTime === null ||
    sessionStart === null ||
    data.time - previousTime > timeframeSeconds
  ) {
    const state: RealtimeState = {
      previousTime: data.time,
      candles: [data],
      sessionStart: data.time,
    };

    return {
      candle: aggregateCandles(state.candles, data.time),
      state,
    };
  }

  const previousBucketStart =
    sessionStart + Math.floor((previousTime - sessionStart) / timeframeSeconds) * timeframeSeconds;

  const currentBucketStart =
    sessionStart + Math.floor((data.time - sessionStart) / timeframeSeconds) * timeframeSeconds;

  let candles: Candle[];

  if (currentBucketStart !== previousBucketStart) {
    candles = [data];
  } else {
    const candleIndex = currentState.candles.findIndex((candle) => candle.time === data.time);

    if (candleIndex === -1) {
      candles = [...currentState.candles, data];
    } else {
      candles = [...currentState.candles];
      candles[candleIndex] = data;
    }
  }

  const state: RealtimeState = {
    previousTime: data.time,
    candles,
    sessionStart,
  };

  return {
    candle: aggregateCandles(candles, currentBucketStart),
    state,
  };
}