# Source code for PIL.BdfFontFile

    #
    # The Python Imaging Library
    # $Id$
    #
    # bitmap distribution font (bdf) file parser
    #
    # history:
    # 1996-05-16 fl   created (as bdf2pil)
    # 1997-08-25 fl   converted to FontFile driver
    # 2001-05-25 fl   removed bogus __init__ call
    # 2002-11-20 fl   robustification (from Kevin Cazabon, Dmitry Vasiliev)
    # 2003-04-22 fl   more robustification (from Graham Dumpleton)
    #
    # Copyright (c) 1997-2003 by Secret Labs AB.
    # Copyright (c) 1997-2003 by Fredrik Lundh.
    #
    # See the README file for information on usage and redistribution.
    #

    """
    Parse X Bitmap Distribution Format (BDF)
    """

    from . import FontFile, Image

    bdf_slant = {
        "R": "Roman",
        "I": "Italic",
        "O": "Oblique",
        "RI": "Reverse Italic",
        "RO": "Reverse Oblique",
        "OT": "Other",
    }

    bdf_spacing = {"P": "Proportional", "M": "Monospaced", "C": "Cell"}

    def bdf_char(f):
        # skip to STARTCHAR
        while True:
            s = f.readline()
            if not s:
                return None
            if s[:9] == b"STARTCHAR":
                break
        id = s[9:].strip().decode("ascii")

        # load symbol properties
        props = {}
        while True:
            s = f.readline()
            if not s or s[:6] == b"BITMAP":
                break
            i = s.find(b" ")
            props[s[:i].decode("ascii")] = s[i + 1 : -1].decode("ascii")

        # load bitmap
        bitmap = []
        while True:
            s = f.readline()
            if not s or s[:7] == b"ENDCHAR":
                break
            bitmap.append(s[:-1])
        bitmap = b"".join(bitmap)

        [x, y, l, d] = [int(p) for p in props["BBX"].split()]
        [dx, dy] = [int(p) for p in props["DWIDTH"].split()]

        bbox = (dx, dy), (l, -d - y, x + l, -d), (0, 0, x, y)

        try:
            im = Image.frombytes("1", (x, y), bitmap, "hex", "1")
        except ValueError:
            # deal with zero-width characters
            im = Image.new("1", (x, y))

        return id, int(props["ENCODING"]), bbox, im

    class BdfFontFile(FontFile.FontFile):
        """Font file plugin for the X11 BDF format."""

        def __init__(self, fp):
            super().__init__()

            s = fp.readline()
            if s[:13] != b"STARTFONT 2.1":
                raise SyntaxError("not a valid BDF file")

            props = {}
            comments = []

            while True:
                s = fp.readline()
                if not s or s[:13] == b"ENDPROPERTIES":
                    break
                i = s.find(b" ")
                props[s[:i].decode("ascii")] = s[i + 1 : -1].decode("ascii")
                if s[:i] in [b"COMMENT", b"COPYRIGHT"]:
                    if s.find(b"LogicalFontDescription") < 0:
                        comments.append(s[i + 1 : -1].decode("ascii"))

            while True:
                c = bdf_char(fp)
                if not c:
                    break
                id, ch, (xy, dst, src), im = c
                if 0 <= ch < len(self.glyph):
                    self.glyph[ch] = xy, dst, src, im