package color

import "math"

// inSRGB indicates whether the given color can be mapped to the sRGB color space.
func inSRGB(l Value, a Value, b Value, chroma Value) bool {
	r, g, b := oklabToLinearRGB(l, a*chroma, b*chroma)
	return r >= 0 && g >= 0 && b >= 0 && r <= 1 && g <= 1 && b <= 1
}

// sRGB performs gamma correction to convert linear RGB to sRGB.
// Source: IEC 61966-2-2
func sRGB(x Value) Value {
	if x < 0 {
		return 0
	}

	if x < 0.0031308 {
		return 12.92 * x
	}

	if x < 1.0 {
		return 1.055*math.Pow(x, 1/2.4) - 0.055
	}

	return 1.0
}