Function computeCategoryStep

src/interaction/findCandlestick.ts:28–49

(data: ReadonlyArray<OHLCDataPoint>)

const categoryStepCache = new WeakMap<ReadonlyArray<OHLCDataPoint>, number>();

const computeCategoryStep = (data: ReadonlyArray<OHLCDataPoint>): number => {
  const cached = categoryStepCache.get(data);
  if (cached !== undefined) return cached;

  const timestamps: number[] = [];
  for (let i = 0; i < data.length; i++) {
    const t = getTimestamp(data[i]);
    if (Number.isFinite(t)) timestamps.push(t);
  }

  if (timestamps.length < 2) return 1;
  timestamps.sort((a, b) => a - b);

  let minStep = Number.POSITIVE_INFINITY;
  for (let i = 1; i < timestamps.length; i++) {
    const d = timestamps[i] - timestamps[i - 1];
    if (d > 0 && d < minStep) minStep = d;
  }
  const step = Number.isFinite(minStep) && minStep > 0 ? minStep : 1;
  categoryStepCache.set(data, step);
  return step;
};

/**
 * Computes the candlestick body width in xScale **range-space** units.