# Source code for PIL.ImageColor

    #
    # The Python Imaging Library
    # $Id$
    #
    # map CSS3-style colour description strings to RGB
    #
    # History:
    # 2002-10-24 fl   Added support for CSS-style color strings
    # 2002-12-15 fl   Added RGBA support
    # 2004-03-27 fl   Fixed remaining int() problems for Python 1.5.2
    # 2004-07-19 fl   Fixed gray/grey spelling issues
    # 2009-03-05 fl   Fixed rounding error in grayscale calculation
    #
    # Copyright (c) 2002-2004 by Secret Labs AB
    # Copyright (c) 2002-2004 by Fredrik Lundh
    #
    # See the README file for information on usage and redistribution.
    #

    import re

    from . import Image

    def getrgb(color):
        """
         Convert a color string to an RGB or RGBA tuple. If the string cannot be
         parsed, this function raises a :py:exc:`ValueError` exception.

        .. versionadded:: 1.1.4

        :param color: A color string
        :return: ``(red, green, blue[, alpha])``
        """
        if len(color) > 100:
            raise ValueError("color specifier is too long")
        color = color.lower()

        rgb = colormap.get(color, None)
        if rgb:
            if isinstance(rgb, tuple):
                return rgb
            colormap[color] = rgb = getrgb(rgb)
            return rgb

        # check for known string formats
        if re.match("#[a-f0-9]{3}$", color):
            return (int(color[1] * 2, 16), int(color[2] * 2, 16), int(color[3] * 2, 16))

        if re.match("#[a-f0-9]{4}$", color):
            return (
                int(color[1] * 2, 16),
                int(color[2] * 2, 16),
                int(color[3] * 2, 16),
                int(color[4] * 2, 16),
            )

        if re.match("#[a-f0-9]{6}$", color):
            return (int(color[1:3], 16), int(color[3:5], 16), int(color[5:7], 16))

        if re.match("#[a-f0-9]{8}$", color):
            return (
                int(color[1:3], 16),
                int(color[3:5], 16),
                int(color[5:7], 16),
                int(color[7:9], 16),
            )

        m = re.match(r"rgb\(\s*(\d+)\s*,\s*(\d+)\s*,\s*(\d+)\s*\)$", color)
        if m:
            return (int(m.group(1)), int(m.group(2)), int(m.group(3)))

        m = re.match(r"rgb\(\s*(\d+)%\s*,\s*(\d+)%\s*,\s*(\d+)%\s*\)$", color)
        if m:
            return (
                int((int(m.group(1)) * 255) / 100.0 + 0.5),
                int((int(m.group(2)) * 255) / 100.0 + 0.5),
                int((int(m.group(3)) * 255) / 100.0 + 0.5),
            )

        m = re.match(
            r"hsl\(\s*(\d+\.?\d*)\s*,\s*(\d+\.?\d*)%\s*,\s*(\d+\.?\d*)%\s*\)$", color
        )
        if m:
            from colorsys import hls_to_rgb

            rgb = hls_to_rgb(
                float(m.group(1)) / 360.0,
                float(m.group(3)) / 100.0,
                float(m.group(2)) / 100.0,
            )
            return (
                int(rgb[0] * 255 + 0.5),
                int(rgb[1] * 255 + 0.5),
                int(rgb[2] * 255 + 0.5),
            )

        m = re.match(
            r"hs[bv]\(\s*(\d+\.?\d*)\s*,\s*(\d+\.?\d*)%\s*,\s*(\d+\.?\d*)%\s*\)$", color
        )
        if m:
            from colorsys import hsv_to_rgb

            rgb = hsv_to_rgb(
                float(m.group(1)) / 360.0,
                float(m.group(2)) / 100.0,
                float(m.group(3)) / 100.0,
            )
            return (
                int(rgb[0] * 255 + 0.5),
                int(rgb[1] * 255 + 0.5),
                int(rgb[2] * 255 + 0.5),
            )

        m = re.match(r"rgba\(\s*(\d+)\s*,\s*(\d+)\s*,\s*(\d+)\s*,\s*(\d+)\s*\)$", color)
        if m:
            return (int(m.group(1)), int(m.group(2)), int(m.group(3)), int(m.group(4)))
        raise ValueError(f"unknown color specifier: {repr(color)}")

    def getcolor(color, mode):
        """
        Same as :py:func:`~PIL.ImageColor.getrgb`, but converts the RGB value to a
        greyscale value if the mode is not color or a palette image. If the string
        cannot be parsed, this function raises a :py:exc:`ValueError` exception.

        .. versionadded:: 1.1.4

        :param color: A color string
        :return: ``(graylevel [, alpha]) or (red, green, blue[, alpha])``
        """
        # same as getrgb, but converts the result to the given mode
        color, alpha = getrgb(color), 255
        if len(color) == 4:
            color, alpha = color[0:3], color[3]

        if Image.getmodebase(mode) == "L":
            r, g, b = color
            # ITU-R Recommendation 601-2 for nonlinear RGB
            # scaled to 24 bits to match the convert's implementation.
            color = (r * 19595 + g * 38470 + b * 7471 + 0x8000) >> 16
            if mode[-1] == "A":
                return (color, alpha)
        else:
            if mode[-1] == "A":
                return color + (alpha,)
        return color

    colormap = {
        # X11 colour table from https://drafts.csswg.org/css-color-4/, with
        # gray/grey spelling issues fixed.  This is a superset of HTML 4.0
        # colour names used in CSS 1.
        "aliceblue": "#f0f8ff",
        "antiquewhite": "#faebd7",
        "aqua": "#00ffff",
        "aquamarine": "#7fffd4",
        "azure": "#f0ffff",
        "beige": "#f5f5dc",
        "bisque": "#ffe4c4",
        "black": "#000000",
        "blanchedalmond": "#ffebcd",
        "blue": "#0000ff",
        "blueviolet": "#8a2be2",
        "brown": "#a52a2a",
        "burlywood": "#deb887",
        "cadetblue": "#5f9ea0",
        "chartreuse": "#7fff00",
        "chocolate": "#d2691e",
        "coral": "#ff7f50",
        "cornflowerblue": "#6495ed",
        "cornsilk": "#fff8dc",
        "crimson": "#dc143c",
        "cyan": "#00ffff",
        "darkblue": "#00008b",
        "darkcyan": "#008b8b",
        "darkgoldenrod": "#b8860b",
        "darkgray": "#a9a9a9",
        "darkgrey": "#a9a9a9",
        "darkgreen": "#006400",
        "darkkhaki": "#bdb76b",
        "darkmagenta": "#8b008b",
        "darkolivegreen": "#556b2f",
        "darkorange": "#ff8c00",
        "darkorchid": "#9932cc",
        "darkred": "#8b0000",
        "darksalmon": "#e9967a",
        "darkseagreen": "#8fbc8f",
        "darkslateblue": "#483d8b",
        "darkslategray": "#2f4f4f",
        "darkslategrey": "#2f4f4f",
        "darkturquoise": "#00ced1",
        "darkviolet": "#9400d3",
        "deeppink": "#ff1493",
        "deepskyblue": "#00bfff",
        "dimgray": "#696969",
        "dimgrey": "#696969",
        "dodgerblue": "#1e90ff",
        "firebrick": "#b22222",
        "floralwhite": "#fffaf0",
        "forestgreen": "#228b22",
        "fuchsia": "#ff00ff",
        "gainsboro": "#dcdcdc",
        "ghostwhite": "#f8f8ff",
        "gold": "#ffd700",
        "goldenrod": "#daa520",
        "gray": "#808080",
        "grey": "#808080",
        "green": "#008000",
        "greenyellow": "#adff2f",
        "honeydew": "#f0fff0",
        "hotpink": "#ff69b4",
        "indianred": "#cd5c5c",
        "indigo": "#4b0082",
        "ivory": "#fffff0",
        "khaki": "#f0e68c",
        "lavender": "#e6e6fa",
        "lavenderblush": "#fff0f5",
        "lawngreen": "#7cfc00",
        "lemonchiffon": "#fffacd",
        "lightblue": "#add8e6",
        "lightcoral": "#f08080",
        "lightcyan": "#e0ffff",
        "lightgoldenrodyellow": "#fafad2",
        "lightgreen": "#90ee90",
        "lightgray": "#d3d3d3",
        "lightgrey": "#d3d3d3",
        "lightpink": "#ffb6c1",
        "lightsalmon": "#ffa07a",
        "lightseagreen": "#20b2aa",
        "lightskyblue": "#87cefa",
        "lightslategray": "#778899",
        "lightslategrey": "#778899",
        "lightsteelblue": "#b0c4de",
        "lightyellow": "#ffffe0",
        "lime": "#00ff00",
        "limegreen": "#32cd32",
        "linen": "#faf0e6",
        "magenta": "#ff00ff",
        "maroon": "#800000",
        "mediumaquamarine": "#66cdaa",
        "mediumblue": "#0000cd",
        "mediumorchid": "#ba55d3",
        "mediumpurple": "#9370db",
        "mediumseagreen": "#3cb371",
        "mediumslateblue": "#7b68ee",
        "mediumspringgreen": "#00fa9a",
        "mediumturquoise": "#48d1cc",
        "mediumvioletred": "#c71585",
        "midnightblue": "#191970",
        "mintcream": "#f5fffa",
        "mistyrose": "#ffe4e1",
        "moccasin": "#ffe4b5",
        "navajowhite": "#ffdead",
        "navy": "#000080",
        "oldlace": "#fdf5e6",
        "olive": "#808000",
        "olivedrab": "#6b8e23",
        "orange": "#ffa500",
        "orangered": "#ff4500",
        "orchid": "#da70d6",
        "palegoldenrod": "#eee8aa",
        "palegreen": "#98fb98",
        "paleturquoise": "#afeeee",
        "palevioletred": "#db7093",
        "papayawhip": "#ffefd5",
        "peachpuff": "#ffdab9",
        "peru": "#cd853f",
        "pink": "#ffc0cb",
        "plum": "#dda0dd",
        "powderblue": "#b0e0e6",
        "purple": "#800080",
        "rebeccapurple": "#663399",
        "red": "#ff0000",
        "rosybrown": "#bc8f8f",
        "royalblue": "#4169e1",
        "saddlebrown": "#8b4513",
        "salmon": "#fa8072",
        "sandybrown": "#f4a460",
        "seagreen": "#2e8b57",
        "seashell": "#fff5ee",
        "sienna": "#a0522d",
        "silver": "#c0c0c0",
        "skyblue": "#87ceeb",
        "slateblue": "#6a5acd",
        "slategray": "#708090",
        "slategrey": "#708090",
        "snow": "#fffafa",
        "springgreen": "#00ff7f",
        "steelblue": "#4682b4",
        "tan": "#d2b48c",
        "teal": "#008080",
        "thistle": "#d8bfd8",
        "tomato": "#ff6347",
        "turquoise": "#40e0d0",
        "violet": "#ee82ee",
        "wheat": "#f5deb3",
        "white": "#ffffff",
        "whitesmoke": "#f5f5f5",
        "yellow": "#ffff00",
        "yellowgreen": "#9acd32",
    }