%PDF- %PDF-
| Direktori : /lib/python3/dist-packages/cssutils/stylesheets/ |
| Current File : //lib/python3/dist-packages/cssutils/stylesheets/mediaquery.py |
"""Implements a DOM for MediaQuery, see
http://www.w3.org/TR/css3-mediaqueries/.
A cssutils implementation, not defined in official DOM.
"""
__all__ = ['MediaQuery']
__docformat__ = 'restructuredtext'
__version__ = '$Id$'
from cssutils.prodparser import *
from cssutils.helper import normalize, pushtoken
import cssutils
import re
import xml.dom
class MediaQuery(cssutils.util._NewBase):#cssutils.util.Base):
"""
A Media Query consists of one of :const:`MediaQuery.MEDIA_TYPES`
and one or more expressions involving media features.
Format::
media_query
: [ONLY | NOT]? S* media_type S* [ AND S* expression ]*
| expression [ AND S* expression ]*
;
media_type
: IDENT
;
expression
: '(' S* media_feature S* [ ':' S* expr ]? ')' S*
;
media_feature
: IDENT
;
"""
MEDIA_TYPES = ['all', 'braille', 'handheld', 'print', 'projection',
'speech', 'screen', 'tty', 'tv', 'embossed']
def __init__(self, mediaText=None, readonly=False, _partof=False):
"""
:param mediaText:
unicodestring of parsable media
# _standalone: True if new from ML parser
"""
super(MediaQuery, self).__init__()
self._wellformed = False
self._mediaType = ''
self._partof = _partof
if mediaText:
self.mediaText = mediaText # sets self._mediaType too
self._partof = False
self._readonly = readonly
def __repr__(self):
return "cssutils.stylesheets.%s(mediaText=%r)" % (
self.__class__.__name__, self.mediaText)
def __str__(self):
return "<cssutils.stylesheets.%s object mediaText=%r at 0x%x>" % (
self.__class__.__name__, self.mediaText, id(self))
def _getMediaText(self):
return cssutils.ser.do_stylesheets_mediaquery(self)
def _setMediaText(self, mediaText):
"""
:param mediaText:
a single media query string, e.g. ``print and (min-width: 25cm)``
:exceptions:
- :exc:`~xml.dom.SyntaxErr`:
Raised if the specified string value has a syntax error and is
unparsable.
- :exc:`~xml.dom.InvalidCharacterErr`:
Raised if the given mediaType is unknown.
- :exc:`~xml.dom.NoModificationAllowedErr`:
Raised if this media query is readonly.
media_query
: [ONLY | NOT]? S* media_type S* [ AND S* expression ]*
| expression [ AND S* expression ]*
;
media_type
: IDENT
;
expression
: '(' S* media_feature S* [ ':' S* expr ]? ')' S*
;
media_feature
: IDENT
;
"""
self._checkReadonly()
expression = lambda: Sequence(PreDef.char(name='expression', char='('),
Prod(name='media_feature',
match=lambda t, v: t == PreDef.types.IDENT
),
Sequence(PreDef.char(name='colon', char=':'),
cssutils.css.value.MediaQueryValueProd(self),
minmax=lambda: (0, 1) # optional
),
PreDef.char(name='expression END', char=')',
stopIfNoMoreMatch=self._partof
)
)
prods = Choice(Sequence(Prod(name='ONLY|NOT', # media_query
match=lambda t, v: t == PreDef.types.IDENT and
normalize(v) in ('only', 'not'),
optional=True,
toStore='not simple'
),
Prod(name='media_type',
match=lambda t, v: t == PreDef.types.IDENT and
normalize(v) in self.MEDIA_TYPES,
stopIfNoMoreMatch=True,
toStore='media_type'
),
Sequence(Prod(name='AND',
match=lambda t, v: t == PreDef.types.IDENT and
normalize(v) == 'and',
toStore='not simple'
),
expression(),
minmax=lambda: (0, None)
)
),
Sequence(expression(),
Sequence(Prod(name='AND',
match=lambda t, v: t == PreDef.types.IDENT and
normalize(v) == 'and'
),
expression(),
minmax=lambda: (0, None)
)
)
)
# parse
ok, seq, store, unused = ProdParser().parse(mediaText,
'MediaQuery',
prods)
self._wellformed = ok
if ok:
try:
media_type = store['media_type']
except KeyError as e:
pass
else:
if 'not simple' not in store:
self.mediaType = media_type.value
# TODO: filter doubles!
self._setSeq(seq)
mediaText = property(_getMediaText, _setMediaText,
doc="The parsable textual representation of the media list.")
def _setMediaType(self, mediaType):
"""
:param mediaType:
one of :attr:`MEDIA_TYPES`
:exceptions:
- :exc:`~xml.dom.SyntaxErr`:
Raised if the specified string value has a syntax error and is
unparsable.
- :exc:`~xml.dom.InvalidCharacterErr`:
Raised if the given mediaType is unknown.
- :exc:`~xml.dom.NoModificationAllowedErr`:
Raised if this media query is readonly.
"""
self._checkReadonly()
nmediaType = normalize(mediaType)
if nmediaType not in self.MEDIA_TYPES:
self._log.error(
'MediaQuery: Syntax Error in media type "%s".' % mediaType,
error=xml.dom.SyntaxErr)
else:
# set
self._mediaType = mediaType
# update seq
for i, x in enumerate(self._seq):
if isinstance(x.value, str):
if normalize(x.value) in ('only', 'not'):
continue
else:
# TODO: simplify!
self._seq[i] = (mediaType, 'IDENT', None, None)
break
else:
self._seq.insert(0, mediaType, 'IDENT')
mediaType = property(lambda self: self._mediaType, _setMediaType,
doc="The media type of this MediaQuery (one of "
":attr:`MEDIA_TYPES`) but only if it is a simple MediaType!")
wellformed = property(lambda self: self._wellformed)