# Source code for PIL.XpmImagePlugin

    #
    # The Python Imaging Library.
    # $Id$
    #
    # XPM File handling
    #
    # History:
    # 1996-12-29 fl   Created
    # 2001-02-17 fl   Use 're' instead of 'regex' (Python 2.1) (0.7)
    #
    # Copyright (c) Secret Labs AB 1997-2001.
    # Copyright (c) Fredrik Lundh 1996-2001.
    #
    # See the README file for information on usage and redistribution.
    #
    from __future__ import annotations

    import re

    from . import Image, ImageFile, ImagePalette
    from ._binary import o8

    # XPM header
    xpm_head = re.compile(b'"([0-9]*) ([0-9]*) ([0-9]*) ([0-9]*)')

    def _accept(prefix):
        return prefix[:9] == b"/* XPM */"

    ##
    # Image plugin for X11 pixel maps.

    class XpmImageFile(ImageFile.ImageFile):
        format = "XPM"
        format_description = "X11 Pixel Map"

        def _open(self):
            if not _accept(self.fp.read(9)):
                msg = "not an XPM file"
                raise SyntaxError(msg)

            # skip forward to next string
            while True:
                s = self.fp.readline()
                if not s:
                    msg = "broken XPM file"
                    raise SyntaxError(msg)
                m = xpm_head.match(s)
                if m:
                    break

            self._size = int(m.group(1)), int(m.group(2))

            pal = int(m.group(3))
            bpp = int(m.group(4))

            if pal > 256 or bpp != 1:
                msg = "cannot read this XPM file"
                raise ValueError(msg)

            #
            # load palette description

            palette = [b"\0\0\0"] * 256

            for _ in range(pal):
                s = self.fp.readline()
                if s[-2:] == b"\r\n":
                    s = s[:-2]
                elif s[-1:] in b"\r\n":
                    s = s[:-1]

                c = s[1]
                s = s[2:-2].split()

                for i in range(0, len(s), 2):
                    if s[i] == b"c":
                        # process colour key
                        rgb = s[i + 1]
                        if rgb == b"None":
                            self.info["transparency"] = c
                        elif rgb[:1] == b"#":
                            # FIXME: handle colour names (see ImagePalette.py)
                            rgb = int(rgb[1:], 16)
                            palette[c] = (
                                o8((rgb >> 16) & 255) + o8((rgb >> 8) & 255) + o8(rgb & 255)
                            )
                        else:
                            # unknown colour
                            msg = "cannot read this XPM file"
                            raise ValueError(msg)
                        break

                else:
                    # missing colour key
                    msg = "cannot read this XPM file"
                    raise ValueError(msg)

            self._mode = "P"
            self.palette = ImagePalette.raw("RGB", b"".join(palette))

            self.tile = [("raw", (0, 0) + self.size, self.fp.tell(), ("P", 0, 1))]

        def load_read(self, bytes):
            #
            # load all image data in one chunk

            xsize, ysize = self.size

            s = [None] * ysize

            for i in range(ysize):
                s[i] = self.fp.readline()[1 : xsize + 1].ljust(xsize)

            return b"".join(s)

    #
    # Registry

    Image.register_open(XpmImageFile.format, XpmImageFile, _accept)

    Image.register_extension(XpmImageFile.format, ".xpm")

    Image.register_mime(XpmImageFile.format, "image/xpm")