export function getRecommendedTickValuesForAQuantitativeRange()

in src/visualComponent/axes/helpers/axisHelper.ts [433:507]
56 lines of code
22 McCabe index (conditional complexity)

export function getRecommendedTickValuesForAQuantitativeRange(
    maxTicks: number,
    scale: ScaleLinear<number, number>,
    minInterval?: number,
    shouldTheMinValueBeIncluded: boolean = false): number[] {

    let tickLabels: number[] = [];

    // if maxticks is zero return none
    if (maxTicks === 0) {
        return tickLabels;
    }

    if (scale.ticks) {
        if (shouldTheMinValueBeIncluded && scale.domain) {
            const domain: number[] = scale.domain();

            const minValue: number = domain[0];
            const maxValue: number = domain[1] !== undefined && domain[1] !== null
                ? domain[1]
                : minValue;

            const span: number = Math.abs(maxValue - minValue);

            let step: number = Math.pow(10, Math.floor(Math.log(span / maxTicks) / Math.LN10));

            const err: number = maxTicks / span * step;

            if (err <= .15) {
                step *= 10;
            } else if (err <= .35) {
                step *= 5;
            } else if (err <= .75) {
                step *= 2;
            }

            if (!isNaN(step) && isFinite(step)) {
                tickLabels = d3Range(minValue, maxValue, step);
            }
        } else {

            tickLabels = scale.ticks(maxTicks);

            if (tickLabels.length > maxTicks && maxTicks > 1) {
                tickLabels = scale.ticks(maxTicks - 1);
            }

            if (tickLabels.length < MinTickCount) {
                tickLabels = scale.ticks(maxTicks + 1);
            }
        }

        tickLabels = createTrueZeroTickLabel(tickLabels);

        if (minInterval && tickLabels.length > 1) {
            let tickInterval: number = tickLabels[1] - tickLabels[0];

            while (tickInterval > 0 && tickInterval < minInterval) {
                for (let i = 1; i < tickLabels.length; i++) {
                    tickLabels.splice(i, 1);
                }

                tickInterval = tickInterval * 2;
            }

            if (tickLabels.length === 1) {
                tickLabels.push(tickLabels[0] + minInterval);
            }
        }

        return tickLabels;
    }

    return tickLabels;
}