"""CSSVariablesDeclaration http://disruptive-innovations.com/zoo/cssvariables/#mozTocId496530 """ __all__ = ['CSSVariablesDeclaration'] __docformat__ = 'restructuredtext' __version__ = '$Id: cssstyledeclaration.py 1819 2009-08-01 20:52:43Z cthedot $' from cssutils.prodparser import * from cssutils.helper import normalize from value import PropertyValue import cssutils import itertools import xml.dom class CSSVariablesDeclaration(cssutils.util._NewBase): """The CSSVariablesDeclaration interface represents a single block of variable declarations. """ def __init__(self, cssText=u'', parentRule=None, readonly=False): """ :param cssText: Shortcut, sets CSSVariablesDeclaration.cssText :param parentRule: The CSS rule that contains this declaration block or None if this CSSVariablesDeclaration is not attached to a CSSRule. :param readonly: defaults to False Format:: variableset : vardeclaration [ ';' S* vardeclaration ]* S* ; vardeclaration : varname ':' S* term ; varname : IDENT S* ; """ super(CSSVariablesDeclaration, self).__init__() self._parentRule = parentRule self._vars = {} if cssText: self.cssText = cssText self._readonly = readonly def __repr__(self): return u"cssutils.css.%s(cssText=%r)" % (self.__class__.__name__, self.cssText) def __str__(self): return u"" % ( self.__class__.__name__, self.length, id(self)) def __contains__(self, variableName): """Check if a variable is in variable declaration block. :param variableName: a string """ return normalize(variableName) in self.keys() def __getitem__(self, variableName): """Retrieve the value of variable ``variableName`` from this declaration. """ return self.getVariableValue(variableName) def __setitem__(self, variableName, value): self.setVariable(variableName, value) def __delitem__(self, variableName): return self.removeVariable(variableName) def __iter__(self): """Iterator of names of set variables.""" for name in self.keys(): yield name def keys(self): """Analoguous to standard dict returns variable names which are set in this declaration.""" return self._vars.keys() def _getCssText(self): """Return serialized property cssText.""" return cssutils.ser.do_css_CSSVariablesDeclaration(self) def _setCssText(self, cssText): """Setting this attribute will result in the parsing of the new value and resetting of all the properties in the declaration block including the removal or addition of properties. :exceptions: - :exc:`~xml.dom.NoModificationAllowedErr`: Raised if this declaration is readonly or a property is readonly. - :exc:`~xml.dom.SyntaxErr`: Raised if the specified CSS string value has a syntax error and is unparsable. Format:: variableset : vardeclaration [ ';' S* vardeclaration ]* ; vardeclaration : varname ':' S* term ; varname : IDENT S* ; expr : [ VARCALL | term ] [ operator [ VARCALL | term ] ]* ; """ self._checkReadonly() vardeclaration = Sequence( PreDef.ident(), PreDef.char(u':', u':', toSeq=False), #PreDef.S(toSeq=False, optional=True), Prod(name=u'term', match=lambda t, v: True, toSeq=lambda t, tokens: (u'value', PropertyValue(itertools.chain([t], tokens), parent=self) ) ) ) prods = Sequence(vardeclaration, Sequence(PreDef.S(optional=True), PreDef.char(u';', u';', toSeq=False), PreDef.S(optional=True), vardeclaration, minmax=lambda: (0, None)), PreDef.S(optional=True), PreDef.char(u';', u';', toSeq=False, optional=True) ) # parse wellformed, seq, store, notused = \ ProdParser().parse(cssText, u'CSSVariableDeclaration', prods) if wellformed: newseq = self._tempSeq() newvars = {} # seq contains only name: value pairs plus comments etc nameitem = None for item in seq: if u'IDENT' == item.type: nameitem = item elif u'value' == item.type: nname = normalize(nameitem.value) if nname in newvars: # replace var with same name for i, it in enumerate(newseq): if normalize(it.value[0]) == nname: newseq.replace(i, (nameitem.value, item.value), 'var', nameitem.line, nameitem.col) else: # saved non normalized name for reserialization newseq.append((nameitem.value, item.value), 'var', nameitem.line, nameitem.col) # newseq.append((nameitem.value, item.value), # 'var', # nameitem.line, nameitem.col) newvars[nname] = item.value else: newseq.appendItem(item) self._setSeq(newseq) self._vars = newvars self.wellformed = True cssText = property(_getCssText, _setCssText, doc=u"(DOM) A parsable textual representation of the declaration " u"block excluding the surrounding curly braces.") def _setParentRule(self, parentRule): self._parentRule = parentRule parentRule = property(lambda self: self._parentRule, _setParentRule, doc=u"(DOM) The CSS rule that contains this" u" declaration block or None if this block" u" is not attached to a CSSRule.") def getVariableValue(self, variableName): """Used to retrieve the value of a variable if it has been explicitly set within this variable declaration block. :param variableName: The name of the variable. :returns: the value of the variable if it has been explicitly set in this variable declaration block. Returns the empty string if the variable has not been set. """ try: return self._vars[normalize(variableName)].cssText except KeyError, e: return u'' def removeVariable(self, variableName): """Used to remove a variable if it has been explicitly set within this variable declaration block. :param variableName: The name of the variable. :returns: the value of the variable if it has been explicitly set for this variable declaration block. Returns the empty string if the variable has not been set. :exceptions: - :exc:`~xml.dom.NoModificationAllowedErr`: Raised if this declaration is readonly is readonly. """ normalname = variableName try: r = self._vars[normalname] except KeyError, e: return u'' else: self.seq._readonly = False if normalname in self._vars: for i, x in enumerate(self.seq): if x.value[0] == variableName: del self.seq[i] self.seq._readonly = True del self._vars[normalname] return r.cssText def setVariable(self, variableName, value): """Used to set a variable value within this variable declaration block. :param variableName: The name of the CSS variable. :param value: The new value of the variable, may also be a PropertyValue object. :exceptions: - :exc:`~xml.dom.SyntaxErr`: Raised if the specified value has a syntax error and is unparsable. - :exc:`~xml.dom.NoModificationAllowedErr`: Raised if this declaration is readonly or the property is readonly. """ self._checkReadonly() # check name wellformed, seq, store, unused = \ ProdParser().parse(normalize(variableName), u'variableName', Sequence(PreDef.ident())) if not wellformed: self._log.error(u'Invalid variableName: %r: %r' % (variableName, value)) else: # check value if isinstance(value, PropertyValue): v = value else: v = PropertyValue(cssText=value, parent=self) if not v.wellformed: self._log.error(u'Invalid variable value: %r: %r' % (variableName, value)) else: # update seq self.seq._readonly = False variableName = normalize(variableName) if variableName in self._vars: for i, x in enumerate(self.seq): if x.value[0] == variableName: self.seq.replace(i, [variableName, v], x.type, x.line, x.col) break else: self.seq.append([variableName, v], 'var') self.seq._readonly = True self._vars[variableName] = v def item(self, index): """Used to retrieve the variables that have been explicitly set in this variable declaration block. The order of the variables retrieved using this method does not have to be the order in which they were set. This method can be used to iterate over all variables in this variable declaration block. :param index: of the variable name to retrieve, negative values behave like negative indexes on Python lists, so -1 is the last element :returns: The name of the variable at this ordinal position. The empty string if no variable exists at this position. """ try: return self.keys()[index] except IndexError: return u'' length = property(lambda self: len(self._vars), doc=u"The number of variables that have been explicitly set in this" u" variable declaration block. The range of valid indices is 0" u" to length-1 inclusive.")