1
1
mirror of https://github.com/Kozea/WeasyPrint.git synced 2024-08-17 16:40:45 +03:00
WeasyPrint/weasyprint/svg/css.py
2024-04-24 10:27:46 +02:00

93 lines
3.7 KiB
Python

"""Apply CSS to SVG documents."""
from urllib.parse import urljoin
import cssselect2
import tinycss2
from ..logger import LOGGER
from .utils import parse_url
def find_stylesheets_rules(tree, stylesheet_rules, url):
"""Find rules among stylesheet rules and imports."""
for rule in stylesheet_rules:
if rule.type == 'at-rule':
if rule.lower_at_keyword == 'import' and rule.content is None:
# TODO: support media types in @import
url_token = tinycss2.parse_one_component_value(rule.prelude)
if url_token.type not in ('string', 'url'):
continue
css_url = parse_url(urljoin(url, url_token.value))
stylesheet = tinycss2.parse_stylesheet(
tree.fetch_url(css_url, 'text/css').decode())
url = css_url.geturl()
yield from find_stylesheets_rules(tree, stylesheet, url)
# TODO: support media types
# if rule.lower_at_keyword == 'media':
elif rule.type == 'qualified-rule':
yield rule
# TODO: warn on error
# if rule.type == 'error':
def parse_declarations(input):
"""Parse declarations in a given rule content."""
normal_declarations = []
important_declarations = []
for declaration in tinycss2.parse_blocks_contents(input):
# TODO: warn on error
# if declaration.type == 'error':
if (declaration.type == 'declaration' and
not declaration.name.startswith('-')):
# Serializing perfectly good tokens just to re-parse them later :(
value = tinycss2.serialize(declaration.value).strip()
declarations = (
important_declarations if declaration.important
else normal_declarations)
declarations.append((declaration.lower_name, value))
return normal_declarations, important_declarations
def parse_stylesheets(tree, url):
"""Find stylesheets and return rule matchers in given tree."""
normal_matcher = cssselect2.Matcher()
important_matcher = cssselect2.Matcher()
# Find stylesheets
# TODO: support contentStyleType on <svg>
stylesheets = []
for element in tree.etree_element.iter():
# https://www.w3.org/TR/SVG/styling.html#StyleElement
if (element.tag == '{http://www.w3.org/2000/svg}style' and
element.get('type', 'text/css') == 'text/css' and
element.text):
# TODO: pass href for relative URLs
# TODO: support media types
# TODO: what if <style> has children elements?
stylesheets.append(tinycss2.parse_stylesheet(
element.text, skip_comments=True, skip_whitespace=True))
# Parse rules and fill matchers
for stylesheet in stylesheets:
for rule in find_stylesheets_rules(tree, stylesheet, url):
normal_declarations, important_declarations = parse_declarations(
rule.content)
try:
selectors = cssselect2.compile_selector_list(rule.prelude)
except cssselect2.parser.SelectorError as exception:
LOGGER.warning(
'Failed to apply CSS rule in SVG rule: %s', exception)
break
for selector in selectors:
if (selector.pseudo_element is None and
not selector.never_matches):
if normal_declarations:
normal_matcher.add_selector(
selector, normal_declarations)
if important_declarations:
important_matcher.add_selector(
selector, important_declarations)
return normal_matcher, important_matcher