public generatePaletteColorScale()

in packages/utilities/fast-colors/src/color-palette.ts [112:214]
97 lines of code
10 McCabe index (conditional complexity)

    public generatePaletteColorScale(): ColorScale {
        // Even when config.baseScalePosition is specified, using 0.5 for the baseColor
        // in the baseScale gives better results. Otherwise very off-center palettes
        // tend to go completely grey at the end furthest from the specified base color.
        const baseColorHSL: ColorHSL = rgbToHSL(this.config.baseColor);
        const baseScale: ColorScale = new ColorScale([
            { position: 0, color: this.config.scaleColorLight },
            { position: 0.5, color: this.config.baseColor },
            { position: 1, color: this.config.scaleColorDark },
        ]);
        const trimmedScale: ColorScale = baseScale.trim(
            this.config.clipLight,
            1 - this.config.clipDark
        );
        const trimmedLight: ColorRGBA64 = trimmedScale.getColor(0);
        const trimmedDark: ColorRGBA64 = trimmedScale.getColor(1);
        let adjustedLight: ColorRGBA64 = trimmedLight;
        let adjustedDark: ColorRGBA64 = trimmedDark;

        if (baseColorHSL.s >= this.config.saturationAdjustmentCutoff) {
            adjustedLight = saturateViaLCH(adjustedLight, this.config.saturationLight);
            adjustedDark = saturateViaLCH(adjustedDark, this.config.saturationDark);
        }

        if (this.config.multiplyLight !== 0) {
            const multiply: ColorRGBA64 = blendMultiply(
                this.config.baseColor,
                adjustedLight
            );
            adjustedLight = interpolateByColorSpace(
                this.config.multiplyLight,
                this.config.interpolationMode,
                adjustedLight,
                multiply
            );
        }

        if (this.config.multiplyDark !== 0) {
            const multiply: ColorRGBA64 = blendMultiply(
                this.config.baseColor,
                adjustedDark
            );
            adjustedDark = interpolateByColorSpace(
                this.config.multiplyDark,
                this.config.interpolationMode,
                adjustedDark,
                multiply
            );
        }

        if (this.config.overlayLight !== 0) {
            const overlay: ColorRGBA64 = blendOverlay(
                this.config.baseColor,
                adjustedLight
            );
            adjustedLight = interpolateByColorSpace(
                this.config.overlayLight,
                this.config.interpolationMode,
                adjustedLight,
                overlay
            );
        }

        if (this.config.overlayDark !== 0) {
            const overlay: ColorRGBA64 = blendOverlay(
                this.config.baseColor,
                adjustedDark
            );
            adjustedDark = interpolateByColorSpace(
                this.config.overlayDark,
                this.config.interpolationMode,
                adjustedDark,
                overlay
            );
        }

        if (this.config.baseScalePosition) {
            if (this.config.baseScalePosition <= 0) {
                return new ColorScale([
                    { position: 0, color: this.config.baseColor },
                    { position: 1, color: adjustedDark.clamp() },
                ]);
            } else if (this.config.baseScalePosition >= 1) {
                return new ColorScale([
                    { position: 0, color: adjustedLight.clamp() },
                    { position: 1, color: this.config.baseColor },
                ]);
            }
            return new ColorScale([
                { position: 0, color: adjustedLight.clamp() },
                {
                    position: this.config.baseScalePosition,
                    color: this.config.baseColor,
                },
                { position: 1, color: adjustedDark.clamp() },
            ]);
        }
        return new ColorScale([
            { position: 0, color: adjustedLight.clamp() },
            { position: 0.5, color: this.config.baseColor },
            { position: 1, color: adjustedDark.clamp() },
        ]);
    }