HSL to HEX

hsl_to_hex.py

def hsl_to_hex(hue: int, saturation_percent: int, lightness_percent: int) -> str:
    red, green, blue = hsl_to_rgb(
        hue=hue,
        saturation_percent=saturation_percent,
        lightness_percent=lightness_percent,
    )

    return rgb_to_hex(red=red, green=green, blue=blue)


def rgb_to_hex(red: int, green: int, blue: int) -> str:
    return "#{red:02x}{green:02x}{blue:02x}".format(red=red, green=green, blue=blue)


def hsl_to_rgb(
    hue: int, saturation_percent: int, lightness_percent: int
) -> tuple[int, int, int]:
    saturation = saturation_percent / 100
    lightness = lightness_percent / 100

    def f(n: int) -> int:
        k = (n + hue / 30) % 12
        a = saturation * min(lightness, 1 - lightness)
        return round((lightness - a * max(-1.0, min(k - 3, 9 - k, 1))) * 255)

    red = f(n=0)
    green = f(n=8)
    blue = f(n=4)

    return red, green, blue


def test_hsl_to_hex() -> None:
    hue = 0
    saturation_percent = 79
    lightness_percent = 58

    test_hex = "#e93f3f"
    calculated_hex = hsl_to_hex(
        hue=hue,
        saturation_percent=saturation_percent,
        lightness_percent=lightness_percent,
    )

    print("test_hex: {test_hex}".format(test_hex=test_hex))
    print("calculated_hex: {calculated_hex}".format(calculated_hex=calculated_hex))


if __name__ == "__main__":
    test_hsl_to_hex()