"""

SAX driver for the pyexpat C module.  This driver works with

pyexpat.__version__ == '2.22'.

"""

version = "0.20"

from xml.sax._exceptions import *

from xml.sax.handler import feature_validation, feature_namespaces

from xml.sax.handler import feature_namespace_prefixes

from xml.sax.handler import feature_external_ges, feature_external_pes

from xml.sax.handler import feature_string_interning

from xml.sax.handler import property_xml_string, property_interning_dict

# xml.parsers.expat does not raise ImportError in Jython

import sys

if sys.platform[:4] == "java":

    raise SAXReaderNotAvailable("expat not available in Java", None)

del sys

try:

    from xml.parsers import expat

except ImportError:

    raise SAXReaderNotAvailable("expat not supported", None)

else:

    if not hasattr(expat, "ParserCreate"):

        raise SAXReaderNotAvailable("expat not supported", None)

from xml.sax import xmlreader, saxutils, handler

AttributesImpl = xmlreader.AttributesImpl

AttributesNSImpl = xmlreader.AttributesNSImpl

# If we're using a sufficiently recent version of Python, we can use

# weak references to avoid cycles between the parser and content

# handler, otherwise we'll just have to pretend.

try:

    import _weakref

except ImportError:

    def _mkproxy(o):

        return o

else:

    import weakref

    _mkproxy = weakref.proxy

    del weakref, _weakref

# --- ExpatLocator

class ExpatLocator(xmlreader.Locator):

    """Locator for use with the ExpatParser class.

    This uses a weak reference to the parser object to avoid creating

    a circular reference between the parser and the content handler.

    """

    def __init__(self, parser):

        self._ref = _mkproxy(parser)

    def getColumnNumber(self):

        parser = self._ref

        if parser._parser is None:

            return None

        return parser._parser.ErrorColumnNumber

    def getLineNumber(self):

        parser = self._ref

        if parser._parser is None:

            return 1

        return parser._parser.ErrorLineNumber

    def getPublicId(self):

        parser = self._ref

        if parser is None:

            return None

        return parser._source.getPublicId()

    def getSystemId(self):

        parser = self._ref

        if parser is None:

            return None

        return parser._source.getSystemId()

# --- ExpatParser

class ExpatParser(xmlreader.IncrementalParser, xmlreader.Locator):

    """SAX driver for the pyexpat C module."""

    def __init__(self, namespaceHandling=0, bufsize=2**16-20):

        xmlreader.IncrementalParser.__init__(self, bufsize)

        self._source = xmlreader.InputSource()

        self._parser = None

        self._namespaces = namespaceHandling

        self._lex_handler_prop = None

        self._parsing = 0

        self._entity_stack = []

        self._external_ges = 1

        self._interning = None

    # XMLReader methods

    def parse(self, source):

        "Parse an XML document from a URL or an InputSource."

        source = saxutils.prepare_input_source(source)

        self._source = source

        self.reset()

        self._cont_handler.setDocumentLocator(ExpatLocator(self))

        xmlreader.IncrementalParser.parse(self, source)

    def prepareParser(self, source):

        if source.getSystemId() != None:

            self._parser.SetBase(source.getSystemId())

    # Redefined setContentHandler to allow changing handlers during parsing

    def setContentHandler(self, handler):

        xmlreader.IncrementalParser.setContentHandler(self, handler)

        if self._parsing:

            self._reset_cont_handler()

    def getFeature(self, name):

        if name == feature_namespaces:

            return self._namespaces

        elif name == feature_string_interning:

            return self._interning is not None

        elif name in (feature_validation, feature_external_pes,

                      feature_namespace_prefixes):

            return 0

        elif name == feature_external_ges:

            return self._external_ges

        raise SAXNotRecognizedException("Feature '%s' not recognized" % name)

    def setFeature(self, name, state):

        if self._parsing:

            raise SAXNotSupportedException("Cannot set features while parsing")

        if name == feature_namespaces:

            self._namespaces = state

        elif name == feature_external_ges:

            self._external_ges = state

        elif name == feature_string_interning:

            if state:

                if self._interning is None:

                    self._interning = {}

            else:

                self._interning = None

        elif name == feature_validation:

            if state:

                raise SAXNotSupportedException(

                    "expat does not support validation")

        elif name == feature_external_pes:

            if state:

                raise SAXNotSupportedException(

                    "expat does not read external parameter entities")

        elif name == feature_namespace_prefixes:

            if state:

                raise SAXNotSupportedException(

                    "expat does not report namespace prefixes")

        else:

            raise SAXNotRecognizedException(

                "Feature '%s' not recognized" % name)

    def getProperty(self, name):

        if name == handler.property_lexical_handler:

            return self._lex_handler_prop

        elif name == property_interning_dict:

            return self._interning

        elif name == property_xml_string:

            if self._parser:

                if hasattr(self._parser, "GetInputContext"):

                    return self._parser.GetInputContext()

                else:

                    raise SAXNotRecognizedException(

                        "This version of expat does not support getting"

                        " the XML string")

            else:

                raise SAXNotSupportedException(

                    "XML string cannot be returned when not parsing")

        raise SAXNotRecognizedException("Property '%s' not recognized" % name)

    def setProperty(self, name, value):

        if name == handler.property_lexical_handler:

            self._lex_handler_prop = value

            if self._parsing:

                self._reset_lex_handler_prop()

        elif name == property_interning_dict:

            self._interning = value

        elif name == property_xml_string:

            raise SAXNotSupportedException("Property '%s' cannot be set" %

                                           name)

        else:

            raise SAXNotRecognizedException("Property '%s' not recognized" %

                                            name)

    # IncrementalParser methods

    def feed(self, data, isFinal = 0):

        if not self._parsing:

            self.reset()

            self._parsing = 1

            self._cont_handler.startDocument()

        try:

            # The isFinal parameter is internal to the expat reader.

            # If it is set to true, expat will check validity of the entire

            # document. When feeding chunks, they are not normally final -

            # except when invoked from close.

            self._parser.Parse(data, isFinal)

        except expat.error, e:

            exc = SAXParseException(expat.ErrorString(e.code), e, self)

            # FIXME: when to invoke error()?

            self._err_handler.fatalError(exc)

    def close(self):

        if self._entity_stack:

            # If we are completing an external entity, do nothing here

            return

        self.feed("", isFinal = 1)

        self._cont_handler.endDocument()

        self._parsing = 0

        # break cycle created by expat handlers pointing to our methods

        self._parser = None

    def _reset_cont_handler(self):

        self._parser.ProcessingInstructionHandler = \

                                    self._cont_handler.processingInstruction

        self._parser.CharacterDataHandler = self._cont_handler.characters

    def _reset_lex_handler_prop(self):

        lex = self._lex_handler_prop

        parser = self._parser

        if lex is None:

            parser.CommentHandler = None

            parser.StartCdataSectionHandler = None

            parser.EndCdataSectionHandler = None

            parser.StartDoctypeDeclHandler = None

            parser.EndDoctypeDeclHandler = None

        else:

            parser.CommentHandler = lex.comment

            parser.StartCdataSectionHandler = lex.startCDATA

            parser.EndCdataSectionHandler = lex.endCDATA

            parser.StartDoctypeDeclHandler = self.start_doctype_decl

            parser.EndDoctypeDeclHandler = lex.endDTD

    def reset(self):

        if self._namespaces:

            self._parser = expat.ParserCreate(self._source.getEncoding(), " ",

                                              intern=self._interning)

            self._parser.namespace_prefixes = 1

            self._parser.StartElementHandler = self.start_element_ns

            self._parser.EndElementHandler = self.end_element_ns

        else:

            self._parser = expat.ParserCreate(self._source.getEncoding(),

                                              intern = self._interning)

            self._parser.StartElementHandler = self.start_element

            self._parser.EndElementHandler = self.end_element

        self._reset_cont_handler()

        self._parser.UnparsedEntityDeclHandler = self.unparsed_entity_decl

        self._parser.NotationDeclHandler = self.notation_decl

        self._parser.StartNamespaceDeclHandler = self.start_namespace_decl

        self._parser.EndNamespaceDeclHandler = self.end_namespace_decl

        self._decl_handler_prop = None

        if self._lex_handler_prop:

            self._reset_lex_handler_prop()

#         self._parser.DefaultHandler =

#         self._parser.DefaultHandlerExpand =

#         self._parser.NotStandaloneHandler =

        self._parser.ExternalEntityRefHandler = self.external_entity_ref

        try:

            self._parser.SkippedEntityHandler = self.skipped_entity_handler

        except AttributeError:

            # This pyexpat does not support SkippedEntity

            pass

        self._parser.SetParamEntityParsing(

            expat.XML_PARAM_ENTITY_PARSING_UNLESS_STANDALONE)

        self._parsing = 0

        self._entity_stack = []

    # Locator methods

    def getColumnNumber(self):

        if self._parser is None:

            return None

        return self._parser.ErrorColumnNumber

    def getLineNumber(self):

        if self._parser is None:

            return 1

        return self._parser.ErrorLineNumber

    def getPublicId(self):

        return self._source.getPublicId()

    def getSystemId(self):

        return self._source.getSystemId()

    # event handlers

    def start_element(self, name, attrs):

        self._cont_handler.startElement(name, AttributesImpl(attrs))

    def end_element(self, name):

        self._cont_handler.endElement(name)

    def start_element_ns(self, name, attrs):

        pair = name.split()

        if len(pair) == 1:

            # no namespace

            pair = (None, name)

        elif len(pair) == 3:

            pair = pair[0], pair[1]

        else:

            # default namespace

            pair = tuple(pair)

        newattrs = {}

        qnames = {}

        for (aname, value) in attrs.items():

            parts = aname.split()

            length = len(parts)

            if length == 1:

                # no namespace

                qname = aname

                apair = (None, aname)

            elif length == 3:

                qname = "%s:%s" % (parts[2], parts[1])

                apair = parts[0], parts[1]

            else:

                # default namespace

                qname = parts[1]

                apair = tuple(parts)

            newattrs[apair] = value

            qnames[apair] = qname

        self._cont_handler.startElementNS(pair, None,

                                          AttributesNSImpl(newattrs, qnames))

    def end_element_ns(self, name):

        pair = name.split()

        if len(pair) == 1:

            pair = (None, name)

        elif len(pair) == 3:

            pair = pair[0], pair[1]

        else:

            pair = tuple(pair)

        self._cont_handler.endElementNS(pair, None)

    # this is not used (call directly to ContentHandler)

    def processing_instruction(self, target, data):

        self._cont_handler.processingInstruction(target, data)

    # this is not used (call directly to ContentHandler)

    def character_data(self, data):

        self._cont_handler.characters(data)

    def start_namespace_decl(self, prefix, uri):

        self._cont_handler.startPrefixMapping(prefix, uri)

    def end_namespace_decl(self, prefix):

        self._cont_handler.endPrefixMapping(prefix)

    def start_doctype_decl(self, name, sysid, pubid, has_internal_subset):

        self._lex_handler_prop.startDTD(name, pubid, sysid)

    def unparsed_entity_decl(self, name, base, sysid, pubid, notation_name):

        self._dtd_handler.unparsedEntityDecl(name, pubid, sysid, notation_name)

    def notation_decl(self, name, base, sysid, pubid):

        self._dtd_handler.notationDecl(name, pubid, sysid)

    def external_entity_ref(self, context, base, sysid, pubid):

        if not self._external_ges:

            return 1

        source = self._ent_handler.resolveEntity(pubid, sysid)

        source = saxutils.prepare_input_source(source,

                                               self._source.getSystemId() or

                                               "")

        self._entity_stack.append((self._parser, self._source))

        self._parser = self._parser.ExternalEntityParserCreate(context)

        self._source = source

        try:

            xmlreader.IncrementalParser.parse(self, source)

        except:

            return 0  # FIXME: save error info here?

        (self._parser, self._source) = self._entity_stack[-1]

        del self._entity_stack[-1]

        return 1

    def skipped_entity_handler(self, name, is_pe):

        if is_pe:

            # The SAX spec requires to report skipped PEs with a '%'

            name = '%'+name

        self._cont_handler.skippedEntity(name)

# ---

def create_parser(*args, **kwargs):

    return ExpatParser(*args, **kwargs)

# ---

if __name__ == "__main__":

    import xml.sax

    p = create_parser()

    p.setContentHandler(xml.sax.XMLGenerator())

    p.setErrorHandler(xml.sax.ErrorHandler())

    p.parse("../../../hamlet.xml")