1#!/usr/bin/env python
2# coding:utf-8
3# Authors:  mozman <me@mozman.at>, Florian Festi
4# Purpose: svgparser using re module
5# Created: 16.10.2010
6# Copyright (c) 2010, Manfred Moitzi & 2020, Florian Festi
7# License: MIT License
8
9__all__ = ["is_valid_transferlist", "is_valid_pathdata", "is_valid_animation_timing"]
10
11import re
12
13event_names = [
14    "focusin", "focusout", "activate", "click", "mousedown", "mouseup", "mouseover",
15    "mousemove", "mouseout", "DOMSubtreeModified", "DOMNodeInserted", "DOMNodeRemoved",
16    "DOMNodeRemovedFromDocument", "DOMNodeInsertedtoDocument", "DOMAttrModified",
17    "DOMCharacterDataModified", "SVGLoad", "SVGUnload", "SVGAbort", "SVGError",
18    "SVGResize", "SVGScroll", "SVGZoom", "beginEvent", "endEvent", "repeatEvent",
19]
20
21c = r"\s*[, ]\s*"
22integer_constant = r"\d+"
23exponent = r"([eE][+-]?\d+)"
24nonnegative_number = fr"(\d+\.?\d*|\.\d+){exponent}?"
25number = r"[+-]?" + nonnegative_number
26flag = r"[01]"
27
28comma_delimited_coordinates = fr"\s*{number}({c}{number})*\s*"
29two_comma_delimited_numbers = fr"\s*{number}({c}{number}\s*)" "{1}"
30four_comma_delimited_numbers = fr"\s*{number}\s*({c}{number}\s*)" "{3}"
31six_comma_delimited_numbers = fr"\s*{number}\s*({c}{number}\s*)" "{5}"
32comma_delimited_coordinate_pairs = fr"{two_comma_delimited_numbers}({c}{two_comma_delimited_numbers})*"
33
34
35def is_valid(regex):
36    reg = re.compile(regex)
37
38    def f(term):
39        return bool(reg.fullmatch(term))
40
41    return f
42
43
44def build_transferlist_parser():
45    matrix = fr"matrix\s*\(\s*{six_comma_delimited_numbers}\s*\)"
46    translate = fr"translate\s*\(\s*{number}({c}{number})?\s*\)"
47    scale = fr"scale\s*\(\s*{number}({c}{number})?\s*\)"
48    rotate = fr"rotate\s*\(\s*{number}({c}{number}{c}{number})?\s*\)"
49    skewX = fr"skewX\s*\(\s*{number}\s*\)"
50    skewY = fr"skewY\s*\(\s*{number}\s*\)"
51
52    tl_re = "|".join((fr"(\s*{cmd}\s*)" for cmd in (
53        matrix, translate, scale, rotate, skewX, skewY)))
54    return fr"({tl_re})({c}({tl_re}))*"
55
56
57is_valid_transferlist = is_valid(build_transferlist_parser())
58
59
60def build_pathdata_parser():
61    moveto = fr"[mM]\s*{comma_delimited_coordinate_pairs}"
62    lineto = fr"[lL]\s*{comma_delimited_coordinate_pairs}"
63    horizontal_lineto = fr"[hH]\s*{comma_delimited_coordinates}"
64    vertical_lineto = fr"[vV]\s*{comma_delimited_coordinates}"
65    curveto = fr"[cC]\s*({six_comma_delimited_numbers})({c}{six_comma_delimited_numbers})*"
66    smooth_curveto = fr"[sS]{four_comma_delimited_numbers}({c}{four_comma_delimited_numbers})*"
67    quadratic_bezier_curveto = fr"[qQ]{four_comma_delimited_numbers}({c}{four_comma_delimited_numbers})*"
68    smooth_quadratic_bezier_curveto = fr"[tT]\s*{comma_delimited_coordinate_pairs}"
69
70    elliptical_arc_argument = fr"{c}".join((
71        fr"{nonnegative_number}",
72        fr"{nonnegative_number}",
73        fr"{number}",
74        fr"{flag}",
75        fr"{flag}",
76        fr"{number}",
77        fr"{number}",))
78    elliptical_arc_argument = r"\s*" + elliptical_arc_argument + r"\s*"
79    elliptical_arc = fr"[aA]({elliptical_arc_argument})({c}{elliptical_arc_argument})*"
80
81    drawto_command = "|".join((fr"(\s*{cmd}\s*)" for cmd in (
82        moveto, lineto, horizontal_lineto, vertical_lineto, "[zZ]",
83        curveto, smooth_curveto, quadratic_bezier_curveto,
84        smooth_quadratic_bezier_curveto, elliptical_arc)))
85
86    return f"{moveto}({drawto_command})*"
87
88
89is_valid_pathdata = is_valid(build_pathdata_parser())
90
91digit2 = r"\d{2}"
92digit4 = r"\d{4}"
93seconds = fr"\d+(\.\d+)?"
94seconds2 = fr"{digit2}(\.\d+)?"
95metric = "(h|min|s|ms)"
96
97
98def clock_val_re():
99    timecount_val = fr"{seconds}\s*({metric})?"
100    clock_val = fr"{digit2}:({digit2}:)?{seconds2}"
101    return fr"({timecount_val}|{clock_val})"
102
103
104def wall_clock_val_re():
105    hhmmss = fr"{digit2}:{digit2}(:{seconds2})?"
106    walltime = fr"{hhmmss}(Z|[+-]?{digit2}:{digit2})?"
107    date = fr"{digit4}-{digit2}-{digit2}"
108    datetime = fr"{date}(T{walltime})?"
109    return "(" + "|".join((walltime, datetime)) + ")"
110
111
112def build_animation_timing_parser():
113    clock_val = clock_val_re()
114    wallclock_val = wall_clock_val_re()
115
116    event_ref = "(" + "|".join(event_names) + ")"
117    id_value = "#?[-_a-zA-Z0-9]+"
118
119    wallclock_sync_value = fr"wallclock\(\s*{wallclock_val}\s*\)"
120    accesskey_value = fr"accessKey\(\s*[a-zA-Z]\s*\)\s*([+-]?{clock_val})?"
121    repeat_value = fr"({id_value}\.)?repeat\s*\(\s*\d+\s*\)\s*([+-?]{clock_val})?"
122    event_value = fr"({id_value}\.)?{event_ref}([+-]?{clock_val})?"
123    offset_value = fr"[-+]?{clock_val}"
124    syncbase_value = fr"{id_value}\.(begin|end)({offset_value})?"
125    begin_value = "(" + "|".join((f"({reg})" for reg in (
126        offset_value, syncbase_value, event_value, repeat_value,
127        accesskey_value, wallclock_sync_value, "indefinite"))) + ")"
128    return fr"{begin_value}({c}{begin_value})*"
129
130
131is_valid_animation_timing = is_valid(build_animation_timing_parser())
132