# Source code for rdflib.tools.rdf2dot

    """
    A commandline tool for drawing RDF graphs in Graphviz DOT format

    You can draw the graph of an RDF file directly:

    .. code-block: bash

       rdf2dot my_rdf_file.rdf | dot -Tpng | display

    """

    import rdflib
    import rdflib.extras.cmdlineutils

    import sys
    import cgi
    import collections

    from rdflib import XSD

    LABEL_PROPERTIES = [rdflib.RDFS.label,
                        rdflib.URIRef("http://purl.org/dc/elements/1.1/title"),
                        rdflib.URIRef("http://xmlns.com/foaf/0.1/name"),
                        rdflib.URIRef("http://www.w3.org/2006/vcard/ns#fn"),
                        rdflib.URIRef("http://www.w3.org/2006/vcard/ns#org")
                        ]

    XSDTERMS = [
        XSD[x] for x in (
            "anyURI", "base64Binary", "boolean", "byte", "date",
            "dateTime", "decimal", "double", "duration", "float", "gDay", "gMonth",
            "gMonthDay", "gYear", "gYearMonth", "hexBinary", "ID", "IDREF",
            "IDREFS", "int", "integer", "language", "long", "Name", "NCName",
            "negativeInteger", "NMTOKEN", "NMTOKENS", "nonNegativeInteger",
            "nonPositiveInteger", "normalizedString", "positiveInteger", "QName",
            "short", "string", "time", "token", "unsignedByte", "unsignedInt",
            "unsignedLong", "unsignedShort")]

    EDGECOLOR = "blue"
    NODECOLOR = "black"
    ISACOLOR = "black"

    def rdf2dot(g, stream, opts={}):
        """
        Convert the RDF graph to DOT
        writes the dot output to the stream
        """

        fields = collections.defaultdict(set)
        nodes = {}

        def node(x):

            if x not in nodes:
                nodes[x] = "node%d" % len(nodes)
            return nodes[x]

        def label(x, g):

            for labelProp in LABEL_PROPERTIES:
                l = g.value(x, labelProp)
                if l:
                    return l

            try:
                return g.namespace_manager.compute_qname(x)[2]
            except:
                return x

        def formatliteral(l, g):
            v = cgi.escape(l)
            if l.datatype:
                return u'&quot;%s&quot;^^%s' % (v, qname(l.datatype, g))
            elif l.language:
                return u'&quot;%s&quot;@%s' % (v, l.language)
            return u'&quot;%s&quot;' % v

        def qname(x, g):
            try:
                q = g.compute_qname(x)
                return q[0] + ":" + q[2]
            except:
                return x

        def color(p):
            return "BLACK"

        stream.write(u"digraph { \n node [ fontname=\"DejaVu Sans\" ] ; \n")

        for s, p, o in g:
            sn = node(s)
            if p == rdflib.RDFS.label:
                continue
            if isinstance(o, (rdflib.URIRef, rdflib.BNode)):
                on = node(o)
                opstr = u"\t%s -> %s [ color=%s, label=< <font point-size='10' " + \
                        u"color='#336633'>%s</font> > ] ;\n"
                stream.write(opstr % (sn, on, color(p), qname(p, g)))
            else:
                fields[sn].add((qname(p, g), formatliteral(o, g)))

        for u, n in nodes.items():
            stream.write(u"# %s %s\n" % (u, n))
            f = [u"<tr><td align='left'>%s</td><td align='left'>%s</td></tr>" %
                 x for x in sorted(fields[n])]
            opstr = u"%s [ shape=none, color=%s label=< <table color='#666666'" + \
                    u" cellborder='0' cellspacing='0' border='1'><tr>" + \
                    u"<td colspan='2' bgcolor='grey'><B>%s</B></td></tr><tr>" + \
                    u"<td href='%s' bgcolor='#eeeeee' colspan='2'>" + \
                    u"<font point-size='10' color='#6666ff'>%s</font></td>" + \
                    u"</tr>%s</table> > ] \n"
            stream.write(opstr % (n, NODECOLOR, label(u, g), u, u, u"".join(f)))

        stream.write("}\n")

    def _help():
        sys.stderr.write("""
    rdf2dot.py [-f <format>] files...
    Read RDF files given on STDOUT, writes a graph of the RDFS schema in DOT
    language to stdout
    -f specifies parser to use, if not given,

    """)

    def main():
        rdflib.extras.cmdlineutils.main(rdf2dot, _help)

    if __name__ == '__main__':
        main()