# -*- coding: utf-8 -*-
"""
Extracting possible embedded RDF/XML content from the file and parse it separately into the Graph. This is used, for example
by U{SVG 1.2 Tiny<http://www.w3.org/TR/SVGMobile12/>}.

@author: U{Ivan Herman<a href="http://www.w3.org/People/Ivan/">}
@license: This software is available for use under the
U{W3C® SOFTWARE NOTICE AND LICENSE<href="http://www.w3.org/Consortium/Legal/2002/copyright-software-20021231">}
@contact: Ivan Herman, ivan@w3.org
@version: $Id: EmbeddedRDF.py,v 1.2 2008-11-11 13:11:16 ivan Exp $
$Date: 2008-11-11 13:11:16 $
"""

from StringIO	import StringIO

def handle_embeddedRDF(node, graph, state) :
	"""
	Check if the node is the top level rdf element for RDF/XML. If so, the content is parsed and added to the target graph. Note that if an separate
	base is defined in the state, the C{xml:base} attribute will be added to the C{rdf} node before parsing.
	@param node: a DOM node for the top level xml element
	@param graph: target rdf graph
	@type graph: RDFLib's Graph object instance
	@param state: the inherited state (namespaces, lang, etc)
	@type state: L{State.ExecutionContext}
	@return: whether an RDF/XML content has been detected or not. If TRUE, the RDFa processing should not occur on the node and its descendents. 
	@rtype: Boolean

	"""
	if node.localName == "RDF" and node.namespaceURI == "http://www.w3.org/1999/02/22-rdf-syntax-ns#" :
		node.setAttribute("xml:base",state.base)
		rdf = StringIO(node.toxml())
		graph.parse(rdf)
		return True
	else :
		return False