# Source code for fontTools.svgLib.path.parser

    # SVG Path specification parser.
    # This is an adaptation from 'svg.path' by Lennart Regebro (@regebro),
    # modified so that the parser takes a FontTools Pen object instead of
    # returning a list of svg.path Path objects.
    # The original code can be found at:
    # https://github.com/regebro/svg.path/blob/4f9b6e3/src/svg/path/parser.py
    # Copyright (c) 2013-2014 Lennart Regebro
    # License: MIT

    from .arc import EllipticalArc
    import re

    COMMANDS = set("MmZzLlHhVvCcSsQqTtAa")
    ARC_COMMANDS = set("Aa")
    UPPERCASE = set("MZLHVCSQTA")

    COMMAND_RE = re.compile("([MmZzLlHhVvCcSsQqTtAa])")

    # https://www.w3.org/TR/css-syntax-3/#number-token-diagram
    #   but -6.e-5 will be tokenized as "-6" then "-5" and confuse parsing
    FLOAT_RE = re.compile(
        r"[-+]?"  # optional sign
        r"(?:"
        r"(?:0|[1-9][0-9]*)(?:\.[0-9]+)?(?:[eE][-+]?[0-9]+)?"  # int/float
        r"|"
        r"(?:\.[0-9]+(?:[eE][-+]?[0-9]+)?)"  # float with leading dot (e.g. '.42')
        r")"
    )
    BOOL_RE = re.compile("^[01]")
    SEPARATOR_RE = re.compile(f"[, \t]")

    def _tokenize_path(pathdef):
        arc_cmd = None
        for x in COMMAND_RE.split(pathdef):
            if x in COMMANDS:
                arc_cmd = x if x in ARC_COMMANDS else None
                yield x
                continue

            if arc_cmd:
                try:
                    yield from _tokenize_arc_arguments(x)
                except ValueError as e:
                    raise ValueError(f"Invalid arc command: '{arc_cmd}{x}'") from e
            else:
                for token in FLOAT_RE.findall(x):
                    yield token

    ARC_ARGUMENT_TYPES = (
        ("rx", FLOAT_RE),
        ("ry", FLOAT_RE),
        ("x-axis-rotation", FLOAT_RE),
        ("large-arc-flag", BOOL_RE),
        ("sweep-flag", BOOL_RE),
        ("x", FLOAT_RE),
        ("y", FLOAT_RE),
    )

    def _tokenize_arc_arguments(arcdef):
        raw_args = [s for s in SEPARATOR_RE.split(arcdef) if s]
        if not raw_args:
            raise ValueError(f"Not enough arguments: '{arcdef}'")
        raw_args.reverse()

        i = 0
        while raw_args:
            arg = raw_args.pop()

            name, pattern = ARC_ARGUMENT_TYPES[i]
            match = pattern.search(arg)
            if not match:
                raise ValueError(f"Invalid argument for '{name}' parameter: {arg!r}")

            j, k = match.span()
            yield arg[j:k]
            arg = arg[k:]

            if arg:
                raw_args.append(arg)

            # wrap around every 7 consecutive arguments
            if i == 6:
                i = 0
            else:
                i += 1

        if i != 0:
            raise ValueError(f"Not enough arguments: '{arcdef}'")

    def parse_path(pathdef, pen, current_pos=(0, 0), arc_class=EllipticalArc):
        """Parse SVG path definition (i.e. "d" attribute of <path> elements)
        and call a 'pen' object's moveTo, lineTo, curveTo, qCurveTo and closePath
        methods.

        If 'current_pos' (2-float tuple) is provided, the initial moveTo will
        be relative to that instead being absolute.

        If the pen has an "arcTo" method, it is called with the original values
        of the elliptical arc curve commands:

        .. code-block::

            pen.arcTo(rx, ry, rotation, arc_large, arc_sweep, (x, y))

        Otherwise, the arcs are approximated by series of cubic Bezier segments
        ("curveTo"), one every 90 degrees.
        """
        # In the SVG specs, initial movetos are absolute, even if
        # specified as 'm'. This is the default behavior here as well.
        # But if you pass in a current_pos variable, the initial moveto
        # will be relative to that current_pos. This is useful.
        current_pos = complex(*current_pos)

        elements = list(_tokenize_path(pathdef))
        # Reverse for easy use of .pop()
        elements.reverse()

        start_pos = None
        command = None
        last_control = None

        have_arcTo = hasattr(pen, "arcTo")

        while elements:
            if elements[-1] in COMMANDS:
                # New command.
                last_command = command  # Used by S and T
                command = elements.pop()
                absolute = command in UPPERCASE
                command = command.upper()
            else:
                # If this element starts with numbers, it is an implicit command
                # and we don't change the command. Check that it's allowed:
                if command is None:
                    raise ValueError(
                        "Unallowed implicit command in %s, position %s"
                        % (pathdef, len(pathdef.split()) - len(elements))
                    )
                last_command = command  # Used by S and T

            if command == "M":
                # Moveto command.
                x = elements.pop()
                y = elements.pop()
                pos = float(x) + float(y) * 1j
                if absolute:
                    current_pos = pos
                else:
                    current_pos += pos

                # M is not preceded by Z; it's an open subpath
                if start_pos is not None:
                    pen.endPath()

                pen.moveTo((current_pos.real, current_pos.imag))

                # when M is called, reset start_pos
                # This behavior of Z is defined in svg spec:
                # http://www.w3.org/TR/SVG/paths.html#PathDataClosePathCommand
                start_pos = current_pos

                # Implicit moveto commands are treated as lineto commands.
                # So we set command to lineto here, in case there are
                # further implicit commands after this moveto.
                command = "L"

            elif command == "Z":
                # Close path
                if current_pos != start_pos:
                    pen.lineTo((start_pos.real, start_pos.imag))
                pen.closePath()
                current_pos = start_pos
                start_pos = None
                command = None  # You can't have implicit commands after closing.

            elif command == "L":
                x = elements.pop()
                y = elements.pop()
                pos = float(x) + float(y) * 1j
                if not absolute:
                    pos += current_pos
                pen.lineTo((pos.real, pos.imag))
                current_pos = pos

            elif command == "H":
                x = elements.pop()
                pos = float(x) + current_pos.imag * 1j
                if not absolute:
                    pos += current_pos.real
                pen.lineTo((pos.real, pos.imag))
                current_pos = pos

            elif command == "V":
                y = elements.pop()
                pos = current_pos.real + float(y) * 1j
                if not absolute:
                    pos += current_pos.imag * 1j
                pen.lineTo((pos.real, pos.imag))
                current_pos = pos

            elif command == "C":
                control1 = float(elements.pop()) + float(elements.pop()) * 1j
                control2 = float(elements.pop()) + float(elements.pop()) * 1j
                end = float(elements.pop()) + float(elements.pop()) * 1j

                if not absolute:
                    control1 += current_pos
                    control2 += current_pos
                    end += current_pos

                pen.curveTo(
                    (control1.real, control1.imag),
                    (control2.real, control2.imag),
                    (end.real, end.imag),
                )
                current_pos = end
                last_control = control2

            elif command == "S":
                # Smooth curve. First control point is the "reflection" of
                # the second control point in the previous path.

                if last_command not in "CS":
                    # If there is no previous command or if the previous command
                    # was not an C, c, S or s, assume the first control point is
                    # coincident with the current point.
                    control1 = current_pos
                else:
                    # The first control point is assumed to be the reflection of
                    # the second control point on the previous command relative
                    # to the current point.
                    control1 = current_pos + current_pos - last_control

                control2 = float(elements.pop()) + float(elements.pop()) * 1j
                end = float(elements.pop()) + float(elements.pop()) * 1j

                if not absolute:
                    control2 += current_pos
                    end += current_pos

                pen.curveTo(
                    (control1.real, control1.imag),
                    (control2.real, control2.imag),
                    (end.real, end.imag),
                )
                current_pos = end
                last_control = control2

            elif command == "Q":
                control = float(elements.pop()) + float(elements.pop()) * 1j
                end = float(elements.pop()) + float(elements.pop()) * 1j

                if not absolute:
                    control += current_pos
                    end += current_pos

                pen.qCurveTo((control.real, control.imag), (end.real, end.imag))
                current_pos = end
                last_control = control

            elif command == "T":
                # Smooth curve. Control point is the "reflection" of
                # the second control point in the previous path.

                if last_command not in "QT":
                    # If there is no previous command or if the previous command
                    # was not an Q, q, T or t, assume the first control point is
                    # coincident with the current point.
                    control = current_pos
                else:
                    # The control point is assumed to be the reflection of
                    # the control point on the previous command relative
                    # to the current point.
                    control = current_pos + current_pos - last_control

                end = float(elements.pop()) + float(elements.pop()) * 1j

                if not absolute:
                    end += current_pos

                pen.qCurveTo((control.real, control.imag), (end.real, end.imag))
                current_pos = end
                last_control = control

            elif command == "A":
                rx = abs(float(elements.pop()))
                ry = abs(float(elements.pop()))
                rotation = float(elements.pop())
                arc_large = bool(int(elements.pop()))
                arc_sweep = bool(int(elements.pop()))
                end = float(elements.pop()) + float(elements.pop()) * 1j

                if not absolute:
                    end += current_pos

                # if the pen supports arcs, pass the values unchanged, otherwise
                # approximate the arc with a series of cubic bezier curves
                if have_arcTo:
                    pen.arcTo(
                        rx,
                        ry,
                        rotation,
                        arc_large,
                        arc_sweep,
                        (end.real, end.imag),
                    )
                else:
                    arc = arc_class(
                        current_pos, rx, ry, rotation, arc_large, arc_sweep, end
                    )
                    arc.draw(pen)

                current_pos = end

        # no final Z command, it's an open path
        if start_pos is not None:
            pen.endPath()