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"""Value related classes. DOM Level 2 CSS CSSValue, CSSPrimitiveValue and CSSValueList are **no longer** supported and are replaced by these new classes. """ __all__ = [ 'PropertyValue', 'Value', 'ColorValue', 'DimensionValue', 'URIValue', 'CSSFunction', 'CSSCalc', 'CSSVariable', 'MSValue', ] import colorsys import re import urllib.parse import cssutils from cssutils.helper import normalize, pushtoken from cssutils.prodparser import Choice, PreDef, Prod, ProdParser, Sequence class PropertyValue(cssutils.util._NewBase): """ An unstructured list like holder for all values defined for a :class:`~cssutils.css.Property`. Contains :class:`~cssutils.css.Value` or subclass objects. Currently there is no access to the combinators of the defined values which might simply be space or comma or slash. You may: - iterate over all contained Value objects (not the separators like ``,``, ``/`` or `` `` though!) - get a Value item by index or use ``PropertyValue[index]`` - find out the number of values defined (unstructured) """ def __init__(self, cssText=None, parent=None, readonly=False): """ :param cssText: the parsable cssText of the value :param readonly: defaults to False """ super().__init__() self.parent = parent self.wellformed = False if cssText is not None: # may be 0 if isinstance(cssText, (int, float)): cssText = str(cssText) # if it is a number self.cssText = cssText self._readonly = readonly def __len__(self): return len(list(self.__items())) def __getitem__(self, index): try: return list(self.__items())[index] except IndexError: return None def __iter__(self): "Generator which iterates over values." yield from self.__items() def __repr__(self): return f"cssutils.css.{self.__class__.__name__}({self.cssText!r})" def __str__(self): return "" % ( self.__class__.__name__, self.length, self.cssText, id(self), ) def __items(self, seq=None): "a generator of Value obects only, no , / or ' '" if seq is None: seq = self.seq return (x.value for x in seq if isinstance(x.value, Value)) def _setCssText(self, cssText): if isinstance(cssText, (int, float)): cssText = str(cssText) # if it is a number """ Format:: unary_operator : '-' | '+' ; operator : '/' S* | ',' S* | /* empty */ ; expr : term [ operator term ]* ; term : unary_operator? [ NUMBER S* | PERCENTAGE S* | LENGTH S* | EMS S* | EXS S* | ANGLE S* | TIME S* | FREQ S* ] | STRING S* | IDENT S* | URI S* | hexcolor | function | UNICODE-RANGE S* ; function : FUNCTION S* expr ')' S* ; /* * There is a constraint on the color that it must * have either 3 or 6 hex-digits (i.e., [0-9a-fA-F]) * after the "#"; e.g., "#000" is OK, but "#abcd" is not. */ hexcolor : HASH S* ; :exceptions: - :exc:`~xml.dom.SyntaxErr`: Raised if the specified CSS string value has a syntax error (according to the attached property) or is unparsable. - :exc:`~xml.dom.InvalidModificationErr`: TODO: Raised if the specified CSS string value represents a different type of values than the values allowed by the CSS property. - :exc:`~xml.dom.NoModificationAllowedErr`: Raised if this value is readonly. """ self._checkReadonly() # used as operator is , / or S nextSor = ',/' term = Choice( _ColorProd(self, nextSor), _DimensionProd(self, nextSor), _URIProd(self, nextSor), _ValueProd(self, nextSor), # _Rect(self, nextSor), # all other functions _CSSVariableProd(self, nextSor), _MSValueProd(self, nextSor), _CalcValueProd(self, nextSor), _CSSFunctionProd(self, nextSor), ) operator = Choice( PreDef.S(toSeq=False), PreDef.char( 'comma', ',', toSeq=lambda t, tokens: ('operator', t[1]), optional=True ), PreDef.char( 'slash', '/', toSeq=lambda t, tokens: ('operator', t[1]), optional=True ), optional=True, ) prods = Sequence( term, Sequence( # mayEnd this Sequence if whitespace operator, # TODO: only when setting via other class # used by variabledeclaration currently PreDef.char('END', ';', stopAndKeep=True, optional=True), # TODO: } and !important ends too! term, minmax=lambda: (0, None), ), ) # parse ok, seq, store, unused = ProdParser().parse(cssText, 'PropertyValue', prods) # must be at least one value! ok = ok and len(list(self.__items(seq))) > 0 for item in seq: if hasattr(item.value, 'wellformed') and not item.value.wellformed: ok = False break self.wellformed = ok if ok: self._setSeq(seq) else: self._log.error( 'PropertyValue: Unknown syntax or no value: %s' % self._valuestr(cssText) ) cssText = property( lambda self: cssutils.ser.do_css_PropertyValue(self), _setCssText, doc="A string representation of the current value.", ) def item(self, index): """ The value at position `index`. Alternatively simple use ``PropertyValue[index]``. :param index: the parsable cssText of the value :exceptions: - :exc:`~IndexError`: Raised if index if out of bounds """ return self[index] length = property(lambda self: len(self), doc="Number of values set.") value = property( lambda self: cssutils.ser.do_css_PropertyValue(self, valuesOnly=True), doc="A string representation of the current value " "without any comments used for validation.", ) class Value(cssutils.util._NewBase): """ Represents a single CSS value. For now simple values of IDENT, STRING, or UNICODE-RANGE values are represented directly as Value objects. Other values like e.g. FUNCTIONs are represented by subclasses with an extended API. """ IDENT = 'IDENT' STRING = 'STRING' UNICODE_RANGE = 'UNICODE-RANGE' URI = 'URI' DIMENSION = 'DIMENSION' NUMBER = 'NUMBER' PERCENTAGE = 'PERCENTAGE' COLOR_VALUE = 'COLOR_VALUE' HASH = 'HASH' FUNCTION = 'FUNCTION' CALC = 'CALC' VARIABLE = 'VARIABLE' _type = None _value = '' def __init__(self, cssText=None, parent=None, readonly=False): super().__init__() self.parent = parent self.wellformed = False if cssText: self.cssText = cssText def __repr__(self): return f"cssutils.css.{self.__class__.__name__}({self.cssText!r})" def __str__(self): return f"" def _setCssText(self, cssText): self._checkReadonly() prods = Choice( PreDef.hexcolor(stop=True), PreDef.ident(stop=True), PreDef.string(stop=True), PreDef.unicode_range(stop=True), ) ok, seq, store, unused = ProdParser().parse(cssText, 'Value', prods) self.wellformed = ok if ok: # only 1 value anyway! self._type = seq[0].type self._value = seq[0].value self._setSeq(seq) cssText = property( lambda self: cssutils.ser.do_css_Value(self), _setCssText, doc='String value of this value.', ) @property def type(self): """ Type of this value, for now the production type like e.g. `DIMENSION` or `STRING`. All types are defined as constants in :class:`~cssutils.css.Value`. """ return self._type def _setValue(self, value): # TODO: check! self._value = value value = property( lambda self: self._value, _setValue, doc="Actual value if possible: An int or float or else " " a string", ) class ColorValue(Value): """ A color value like rgb(), rgba(), hsl(), hsla() or #rgb, #rrggbb TODO: Color Keywords """ from .colors import COLORS type = Value.COLOR_VALUE # hexcolor, FUNCTION? _colorType = None _red = 0 _green = 0 _blue = 0 _alpha = 0 def __str__(self): return ( "" % ( self.__class__.__name__, self.type, self.value, self.colorType, self.red, self.green, self.blue, self.alpha, id(self), ) ) def _setCssText(self, cssText): # noqa: C901 self._checkReadonly() types = self._prods # rename! component = Choice( PreDef.unary( toSeq=lambda t, tokens: ( t[0], DimensionValue(pushtoken(t, tokens), parent=self), ) ), PreDef.number( toSeq=lambda t, tokens: ( t[0], DimensionValue(pushtoken(t, tokens), parent=self), ) ), PreDef.percentage( toSeq=lambda t, tokens: ( t[0], DimensionValue(pushtoken(t, tokens), parent=self), ) ), ) noalp = Sequence( Prod( name='FUNCTION', match=lambda t, v: t == types.FUNCTION and v in ('rgb(', 'hsl('), toSeq=lambda t, tokens: (t[0], normalize(t[1])), ), component, Sequence(PreDef.comma(optional=True), component, minmax=lambda: (2, 2)), PreDef.funcEnd(stop=True), ) witha = Sequence( Prod( name='FUNCTION', match=lambda t, v: t == types.FUNCTION and v in ('rgba(', 'hsla('), toSeq=lambda t, tokens: (t[0], normalize(t[1])), ), component, Sequence(PreDef.comma(optional=True), component, minmax=lambda: (3, 3)), PreDef.funcEnd(stop=True), ) namedcolor = Prod( name='Named Color', match=lambda t, v: t == 'IDENT' and (normalize(v) in list(self.COLORS.keys())), stop=True, ) prods = Choice(PreDef.hexcolor(stop=True), namedcolor, noalp, witha) ok, seq, store, unused = ProdParser().parse(cssText, self.type, prods) self.wellformed = ok if ok: t, v = seq[0].type, seq[0].value if 'IDENT' == t: rgba = self.COLORS[normalize(v)] if 'HASH' == t: if len(v) == 4: # HASH #rgb rgba = ( int(2 * v[1], 16), int(2 * v[2], 16), int(2 * v[3], 16), 1.0, ) else: # HASH #rrggbb rgba = (int(v[1:3], 16), int(v[3:5], 16), int(v[5:7], 16), 1.0) elif 'FUNCTION' == t: functiontype, raw, check = None, [], '' HSL = False for item in seq: try: type_ = item.value.type except AttributeError: # type of function, e.g. rgb( if item.type == 'FUNCTION': functiontype = item.value HSL = functiontype in ('hsl(', 'hsla(') continue # save components if type_ == Value.NUMBER: raw.append(item.value.value) check += 'N' elif type_ == Value.PERCENTAGE: if HSL: # save as percentage fraction raw.append(item.value.value / 100.0) else: # save as real value of percentage of 255 raw.append(int(255 * item.value.value / 100)) check += 'P' if HSL: # convert to rgb # h is 360 based (circle) h, s, l_ = raw[0] / 360.0, raw[1], raw[2] # ORDER h l s !!! r, g, b = colorsys.hls_to_rgb(h, l_, s) # back to 255 based rgba = [ int(round(r * 255)), int(round(g * 255)), int(round(b * 255)), ] if len(raw) > 3: rgba.append(raw[3]) else: # rgb, rgba rgba = raw if len(rgba) < 4: rgba.append(1.0) # validate checks = { 'rgb(': ('NNN', 'PPP'), 'rgba(': ('NNNN', 'PPPN'), 'hsl(': ('NPP',), 'hsla(': ('NPPN',), } if check not in checks[functiontype]: self._log.error( 'ColorValue has invalid %s) parameters: ' '%s (N=Number, P=Percentage)' % (functiontype, check) ) self._colorType = t self._red, self._green, self._blue, self._alpha = tuple(rgba) self._setSeq(seq) cssText = property( lambda self: cssutils.ser.do_css_ColorValue(self), _setCssText, doc="String value of this value.", ) value = property( lambda self: cssutils.ser.do_css_CSSFunction(self, True), doc='Same as cssText but without comments.', ) @property def type(self): """Type is fixed to Value.COLOR_VALUE.""" return Value.COLOR_VALUE def _getName(self): for n, v in list(self.COLORS.items()): if v == (self.red, self.green, self.blue, self.alpha): return n colorType = property( lambda self: self._colorType, doc="IDENT (red), HASH (#f00) or FUNCTION (rgb(255, 0, 0).", ) name = property( _getName, doc='Name of the color if known (in ColorValue.COLORS) ' 'else None' ) red = property(lambda self: self._red, doc='red part as integer between 0 and 255') @property def green(self): """green part as integer between 0 and 255""" return self._green @property def blue(self): """blue part as integer between 0 and 255""" return self._blue @property def alpha(self): """alpha part as float between 0.0 and 1.0""" return self._alpha class DimensionValue(Value): """ A numerical value with an optional dimension like e.g. "px" or "%". Covers DIMENSION, PERCENTAGE or NUMBER values. """ __reUnNumDim = re.compile(r'^([+-]?)(\d*\.\d+|\d+)(.*)$', re.I | re.U | re.X) _dimension = None _sign = None def __str__(self): return ( "" % ( self.__class__.__name__, self.type, self.value, self.dimension, self.cssText, id(self), ) ) def _setCssText(self, cssText): self._checkReadonly() prods = Sequence( # PreDef.unary(), Choice( PreDef.dimension(stop=True), PreDef.number(stop=True), PreDef.percentage(stop=True), ) ) ok, seq, store, unused = ProdParser().parse(cssText, 'DimensionValue', prods) self.wellformed = ok if ok: item = seq[0] sign, v, d = self.__reUnNumDim.findall(normalize(item.value))[0] if '.' in v: val = float(sign + v) else: val = int(sign + v) dim = None if d: dim = d self._sign = sign self._value = val self._dimension = dim self._type = item.type self._setSeq(seq) cssText = property( lambda self: cssutils.ser.do_css_Value(self), _setCssText, doc="String value of this value including dimension.", ) dimension = property( lambda self: self._dimension, # _setValue, doc="Dimension if a DIMENSION or PERCENTAGE value, " "else None", ) class URIValue(Value): """ An URI value like ``url(example.png)``. """ _type = Value.URI _uri = Value._value def __str__(self): return f"" def _setCssText(self, cssText): self._checkReadonly() prods = Sequence(PreDef.uri(stop=True)) ok, seq, store, unused = ProdParser().parse(cssText, 'URIValue', prods) self.wellformed = ok if ok: # only 1 value only anyway self._type = seq[0].type self._value = seq[0].value self._setSeq(seq) cssText = property( lambda self: cssutils.ser.do_css_Value(self), _setCssText, doc='String value of this value.', ) def _setUri(self, uri): # TODO: check? self._value = uri uri = property( lambda self: self._value, _setUri, doc="Actual URL without delimiters or the empty string", ) def absoluteUri(self): """Actual URL, made absolute if possible, else same as `uri`.""" # Ancestry: PropertyValue, Property, CSSStyleDeclaration, CSSStyleRule, # CSSStyleSheet try: # TODO: better way? styleSheet = self.parent.parent.parent.parentRule.parentStyleSheet except AttributeError: return self.uri else: return urllib.parse.urljoin(styleSheet.href, self.uri) absoluteUri = property(absoluteUri, doc=absoluteUri.__doc__) class CSSFunction(Value): """ A function value. """ _functionName = 'Function' def _productions(self): """Return definition used for parsing.""" types = self._prods # rename! itemProd = Choice( _ColorProd(self), _DimensionProd(self), _URIProd(self), _ValueProd(self), _CalcValueProd(self), _CSSVariableProd(self), _CSSFunctionProd(self), ) funcProds = Sequence( Prod( name='FUNCTION', match=lambda t, v: t == types.FUNCTION, toSeq=lambda t, tokens: (t[0], normalize(t[1])), ), Choice( Sequence( itemProd, Sequence( PreDef.comma(optional=True), itemProd, minmax=lambda: (0, None) ), PreDef.funcEnd(stop=True), ), PreDef.funcEnd(stop=True), ), ) return funcProds def _setCssText(self, cssText): self._checkReadonly() ok, seq, store, unused = ProdParser().parse( cssText, self.type, self._productions() ) self.wellformed = ok if ok: self._setSeq(seq) cssText = property( lambda self: cssutils.ser.do_css_CSSFunction(self), _setCssText, doc="String value of this value.", ) value = property( lambda self: cssutils.ser.do_css_CSSFunction(self, True), doc='Same as cssText but without comments.', ) type = property(lambda self: Value.FUNCTION, doc="Type is fixed to Value.FUNCTION.") class MSValue(CSSFunction): """An IE specific Microsoft only function value which is much looser in what is syntactically allowed.""" _functionName = 'MSValue' def _productions(self): """Return definition used for parsing.""" types = self._prods # rename! func = Prod( name='MSValue-Sub', match=lambda t, v: t == self._prods.FUNCTION, toSeq=lambda t, tokens: ( MSValue._functionName, MSValue(pushtoken(t, tokens), parent=self), ), ) funcProds = Sequence( Prod( name='FUNCTION', match=lambda t, v: t == types.FUNCTION, toSeq=lambda t, tokens: (t[0], t[1]), ), Sequence( Choice( _ColorProd(self), _DimensionProd(self), _URIProd(self), _ValueProd(self), _MSValueProd(self), # _CalcValueProd(self), _CSSVariableProd(self), func, # _CSSFunctionProd(self), Prod( name='MSValuePart', match=lambda t, v: v != ')', toSeq=lambda t, tokens: (t[0], t[1]), ), ), minmax=lambda: (0, None), ), PreDef.funcEnd(stop=True), ) return funcProds def _setCssText(self, cssText): super()._setCssText(cssText) cssText = property( lambda self: cssutils.ser.do_css_MSValue(self), _setCssText, doc="String value of this value.", ) class CSSCalc(CSSFunction): """The CSSCalc function represents a CSS calc() function. No further API is provided. For multiplication and division no check if one operand is a NUMBER is made. """ _functionName = 'CSSCalc' def __str__(self): return f"" def _setCssText(self, cssText): self._checkReadonly() types = self._prods # rename! _operator = Choice( Prod( name='Operator */', match=lambda t, v: v in '*/', toSeq=lambda t, tokens: (t[0], t[1]), ), Sequence( PreDef.S(), Choice( Sequence( Prod( name='Operator */', match=lambda t, v: v in '*/', toSeq=lambda t, tokens: (t[0], t[1]), ), PreDef.S(optional=True), ), Sequence( Prod( name='Operator +-', match=lambda t, v: v in '+-', toSeq=lambda t, tokens: (t[0], t[1]), ), PreDef.S(), ), PreDef.funcEnd(stop=True, mayEnd=True), ), ), ) _operant = lambda: Choice( # noqa:E731 _DimensionProd(self), _CalcValueProd(self), _CSSVariableProd(self) ) prods = Sequence( Prod( name='CALC', match=lambda t, v: t == types.FUNCTION and normalize(v) == 'calc(', ), PreDef.S(optional=True), _operant(), Sequence(_operator, _operant(), minmax=lambda: (0, None)), PreDef.funcEnd(stop=True), ) # store: name of variable ok, seq, store, unused = ProdParser().parse( cssText, 'CSSCalc', prods, checkS=True ) self.wellformed = ok if ok: self._setSeq(seq) cssText = property( lambda self: cssutils.ser.do_css_CSSCalc(self), _setCssText, doc="String representation of calc function.", ) type = property(lambda self: Value.CALC, doc="Type is fixed to Value.CALC.") class CSSVariable(CSSFunction): """The CSSVariable represents a CSS variables like ``var(varname)``. A variable has a (nonnormalized!) `name` and a `value` which is tried to be resolved from any available CSSVariablesRule definition. """ _functionName = 'CSSVariable' _name = None _fallback = None def __str__(self): return f"" def _setCssText(self, cssText): self._checkReadonly() types = self._prods # rename! prods = Sequence( Prod( name='var', match=lambda t, v: t == types.FUNCTION and normalize(v) == 'var(', ), PreDef.ident(toStore='ident'), Sequence( PreDef.comma(), Choice( _ColorProd(self, toStore='fallback'), _DimensionProd(self, toStore='fallback'), _URIProd(self, toStore='fallback'), _ValueProd(self, toStore='fallback'), _CalcValueProd(self, toStore='fallback'), _CSSVariableProd(self, toStore='fallback'), _CSSFunctionProd(self, toStore='fallback'), ), minmax=lambda: (0, 1), ), PreDef.funcEnd(stop=True), ) # store: name of variable store = {'ident': None, 'fallback': None} ok, seq, store, unused = ProdParser().parse(cssText, 'CSSVariable', prods) self.wellformed = ok if ok: self._name = store['ident'].value try: self._fallback = store['fallback'].value except KeyError: self._fallback = None self._setSeq(seq) cssText = property( lambda self: cssutils.ser.do_css_CSSVariable(self), _setCssText, doc="String representation of variable.", ) # TODO: writable? check if var (value) available? name = property( lambda self: self._name, doc="The name identifier of this variable referring to " "a value in a " ":class:`cssutils.css.CSSVariablesDeclaration`.", ) @property def fallback(self): """The fallback Value of this variable""" return self._fallback type = property(lambda self: Value.VARIABLE, doc="Type is fixed to Value.VARIABLE.") def _getValue(self): "Find contained sheet and @variables there" rel = self while True: # find node which has parentRule to get to StyleSheet if hasattr(rel, 'parent'): rel = rel.parent else: break try: variables = rel.parentRule.parentStyleSheet.variables except AttributeError: return None else: try: return variables[self.name] except KeyError: return None value = property(_getValue, doc='The resolved actual value or None.') # helper for productions def _ValueProd(parent, nextSor=False, toStore=None): return Prod( name='Value', match=lambda t, v: t in ('IDENT', 'STRING', 'UNICODE-RANGE'), nextSor=nextSor, toStore=toStore, toSeq=lambda t, tokens: ('Value', Value(pushtoken(t, tokens), parent=parent)), ) def _DimensionProd(parent, nextSor=False, toStore=None): return Prod( name='Dimension', match=lambda t, v: t in ('DIMENSION', 'NUMBER', 'PERCENTAGE'), nextSor=nextSor, toStore=toStore, toSeq=lambda t, tokens: ( 'DIMENSION', DimensionValue(pushtoken(t, tokens), parent=parent), ), ) def _URIProd(parent, nextSor=False, toStore=None): return Prod( name='URIValue', match=lambda t, v: t == 'URI', toStore=toStore, nextSor=nextSor, toSeq=lambda t, tokens: ( 'URIValue', URIValue(pushtoken(t, tokens), parent=parent), ), ) reHexcolor = re.compile(r'^\#(?:[0-9abcdefABCDEF]{3}|[0-9abcdefABCDEF]{6})$') def _ColorProd(parent, nextSor=False, toStore=None): return Prod( name='ColorValue', match=lambda t, v: (t == 'HASH' and reHexcolor.match(v)) or (t == 'FUNCTION' and normalize(v) in ('rgb(', 'rgba(', 'hsl(', 'hsla(')) or (t == 'IDENT' and normalize(v) in list(ColorValue.COLORS.keys())), nextSor=nextSor, toStore=toStore, toSeq=lambda t, tokens: ( 'ColorValue', ColorValue(pushtoken(t, tokens), parent=parent), ), ) def _CSSFunctionProd(parent, nextSor=False, toStore=None): return PreDef.function( nextSor=nextSor, toStore=toStore, toSeq=lambda t, tokens: ( CSSFunction._functionName, CSSFunction(pushtoken(t, tokens), parent=parent), ), ) def _CalcValueProd(parent, nextSor=False, toStore=None): return Prod( name=CSSCalc._functionName, match=lambda t, v: t == PreDef.types.FUNCTION and normalize(v) == 'calc(', toStore=toStore, toSeq=lambda t, tokens: ( CSSCalc._functionName, CSSCalc(pushtoken(t, tokens), parent=parent), ), nextSor=nextSor, ) def _CSSVariableProd(parent, nextSor=False, toStore=None): return PreDef.variable( nextSor=nextSor, toStore=toStore, toSeq=lambda t, tokens: ( CSSVariable._functionName, CSSVariable(pushtoken(t, tokens), parent=parent), ), ) def _MSValueProd(parent, nextSor=False): return Prod( name=MSValue._functionName, match=lambda t, v: ( # t == self._prods.FUNCTION and ( normalize(v) in ( 'expression(', 'alpha(', 'blur(', 'chroma(', 'dropshadow(', 'fliph(', 'flipv(', 'glow(', 'gray(', 'invert(', 'mask(', 'shadow(', 'wave(', 'xray(', ) or v.startswith('progid:DXImageTransform.Microsoft.') ), nextSor=nextSor, toSeq=lambda t, tokens: ( MSValue._functionName, MSValue(pushtoken(t, tokens), parent=parent), ), ) def MediaQueryValueProd(parent): return Choice( _ColorProd(parent), _DimensionProd(parent), _ValueProd(parent), )