/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 * 
 *      http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

/*
 * $Id: DOMImplementationImpl.cpp 568078 2007-08-21 11:43:25Z amassari $
 */

#include "DOMImplementationImpl.hpp"
#include "DOMDocumentImpl.hpp"
#include "DOMDocumentTypeImpl.hpp"
#include "DOMWriterImpl.hpp"

#include <xercesc/dom/DOMDocument.hpp>
#include <xercesc/dom/DOMDocumentType.hpp>
#include <xercesc/dom/DOMException.hpp>
#include <xercesc/util/PlatformUtils.hpp>
#include <xercesc/util/XMLInitializer.hpp>
#include <xercesc/util/XMLUniDefs.hpp>
#include <xercesc/util/XMLChar.hpp>
#include <xercesc/util/XMLRegisterCleanup.hpp>
#include <xercesc/util/XMLStringTokenizer.hpp>
#include <xercesc/util/XMLDOMMsg.hpp>
#include <xercesc/util/XMLMsgLoader.hpp>
#include <xercesc/parsers/DOMBuilderImpl.hpp>

XERCES_CPP_NAMESPACE_BEGIN


// ------------------------------------------------------------
//
//  Static constants.  These are lazily initialized on first usage.
//                     (Static constructors can not be safely used because
//                      of order of initialization dependencies.)
// ------------------------------------------------------------
static const XMLCh  g1_0[] =     // Points to "1.0"
        {chDigit_1, chPeriod, chDigit_0, chNull};
static const XMLCh  g2_0[] =      // Points to "2.0"
        {chDigit_2, chPeriod, chDigit_0, chNull};
static const XMLCh  g3_0[] =      // Points to "3.0"
        {chDigit_3, chPeriod, chDigit_0, chNull};
static const XMLCh  gTrav[] =     // Points to "Traversal"
        {chLatin_T, chLatin_r, chLatin_a, chLatin_v, chLatin_e, chLatin_r,
            chLatin_s, chLatin_a, chLatin_l, chNull};
static const XMLCh  gCore[] =     // Points to "Core"
        {chLatin_C, chLatin_o, chLatin_r, chLatin_e, chNull};
static const XMLCh  gRange[] =     // Points to "Range"
        {chLatin_R, chLatin_a, chLatin_n, chLatin_g, chLatin_e, chNull};
static const XMLCh  gLS[] =     // Points to "LS"
        {chLatin_L, chLatin_S, chNull};


// -----------------------------------------------------------------------
//  Message Loader for DOM
// -----------------------------------------------------------------------
static XMLMsgLoader  *sMsgLoader4DOM = 0;   // Points to the singleton instance
static XMLMutex      *sMutex4DOM = 0;
static XMLRegisterCleanup mutex4DOMCleanup;
static XMLRegisterCleanup msgLoader4DOMCleanup;

static void reinitMsgLoader4DOM()
{
	delete sMsgLoader4DOM;
	sMsgLoader4DOM = 0;
}

static void reinitMutex4DOM()
{
	delete sMutex4DOM;
	sMutex4DOM = 0;
}

static XMLMutex& getMutex4DOM()
{
    if (!sMutex4DOM)
    {
        XMLMutexLock lock(XMLPlatformUtils::fgAtomicMutex);

        // If we got here first, then register it and set the registered flag
        if (!sMutex4DOM)
        {
            sMutex4DOM = new XMLMutex(XMLPlatformUtils::fgMemoryManager);
            mutex4DOMCleanup.registerCleanup(reinitMutex4DOM);
        }
    }
    return *sMutex4DOM;
}

XMLMsgLoader* DOMImplementationImpl::getMsgLoader4DOM()
{
    if (!sMsgLoader4DOM)
    {
        XMLMutexLock lock(&getMutex4DOM());

        if (!sMsgLoader4DOM)
        {
            sMsgLoader4DOM = XMLPlatformUtils::loadMsgSet(XMLUni::fgXMLDOMMsgDomain);

            if (!sMsgLoader4DOM)
                XMLPlatformUtils::panic(PanicHandler::Panic_CantLoadMsgDomain);
            else
                msgLoader4DOMCleanup.registerCleanup(reinitMsgLoader4DOM);
        }
    }

    return sMsgLoader4DOM;
}

void XMLInitializer::initializeMsgLoader4DOM()
{
    sMsgLoader4DOM = XMLPlatformUtils::loadMsgSet(XMLUni::fgXMLDOMMsgDomain);
    if (sMsgLoader4DOM) {
        msgLoader4DOMCleanup.registerCleanup(reinitMsgLoader4DOM);
    }
}

// -----------------------------------------------------------------------
//  Singleton DOMImplementationImpl
// -----------------------------------------------------------------------
static DOMImplementationImpl    *gDomimp = 0;   // Points to the singleton instance
                                            //  of DOMImplementation that is returnedreturned
                                            //  by any call to getImplementation().
static XMLRegisterCleanup implementationCleanup;

static void reinitImplementation()
{
	delete gDomimp;
	gDomimp = 0;
}

//  getImplementation()  - Always returns the same singleton instance, which
//                         is lazily created on the first call.  Note that
//                         DOM_Implementation must be thread-safe because
//                         it is common to all DOM documents, and while a single
//                         document is not thread-safe within itself, we do
//                         promise that different documents can safely be
//                         used concurrently by different threads.
//
DOMImplementationImpl *DOMImplementationImpl::getDOMImplementationImpl()
{
    if (!gDomimp)
    {
        XMLMutexLock lock(&getMutex4DOM());

        if (!gDomimp)
        {
            gDomimp = new DOMImplementationImpl;
            implementationCleanup.registerCleanup(reinitImplementation);
        }
    }

    return gDomimp;
}

void XMLInitializer::initializeDOMImplementationImpl()
{
    gDomimp = new DOMImplementationImpl;
    if (gDomimp) {
        implementationCleanup.registerCleanup(reinitImplementation);
    }
}

// ------------------------------------------------------------
// DOMImplementation Virtual interface
// ------------------------------------------------------------
bool  DOMImplementationImpl::hasFeature(const  XMLCh * feature,  const  XMLCh * version) const
{
    if (!feature)
        return false;

    bool anyVersion = (version == 0 || !*version);
    bool version1_0 = XMLString::equals(version, g1_0);
    bool version2_0 = XMLString::equals(version, g2_0);
    bool version3_0 = XMLString::equals(version, g3_0);

    // Currently, we support only XML Level 1 version 1.0
    if (XMLString::compareIStringASCII(feature, XMLUni::fgXMLString) == 0
        && (anyVersion || version1_0 || version2_0))
        return true;

    if (XMLString::compareIStringASCII(feature, gCore) == 0
        && (anyVersion || version1_0 || version2_0 || version3_0))
        return true;

    if (XMLString::compareIStringASCII(feature, gTrav) == 0
        && (anyVersion || version2_0))
        return true;

    if (XMLString::compareIStringASCII(feature, gRange) == 0
        && (anyVersion || version2_0))
        return true;

    if (XMLString::compareIStringASCII(feature, gLS) == 0
        && (anyVersion || version3_0))
        return true;

    return false;
}


//Introduced in DOM Level 2
DOMDocumentType *DOMImplementationImpl::createDocumentType(const XMLCh *qualifiedName,
	const XMLCh * publicId, const XMLCh *systemId)
{
    // assume XML 1.0 since we do not know its version yet.
    if(!XMLChar1_0::isValidName(qualifiedName))
        throw DOMException(DOMException::INVALID_CHARACTER_ERR, 0);

    //to do: do we need to create with user's memorymanager???
    DOMDocumentTypeImpl* docType = new DOMDocumentTypeImpl(0, qualifiedName, publicId, systemId, true);
    return docType;
}

DOMDocument *DOMImplementationImpl::createDocument(const XMLCh *namespaceURI,
	const XMLCh *qualifiedName, DOMDocumentType *doctype,
    MemoryManager* const manager)
{
    return new (manager) DOMDocumentImpl(namespaceURI, qualifiedName, doctype, manager);
}


//Introduced in DOM Level 3
DOMImplementation* DOMImplementationImpl::getInterface(const XMLCh*){
    throw DOMException(DOMException::NOT_SUPPORTED_ERR, 0);

    return 0;
}

// Non-standard extension
DOMDocument *DOMImplementationImpl::createDocument(MemoryManager* const manager)
{
        return new (manager) DOMDocumentImpl(manager);
}

//
//  DOMImplementation::getImplementation.  DOMImplementation is supposed to
//                                              be a pure interface class.  This one static
//                                              function is the hook that lets things get started.
DOMImplementation *DOMImplementation::getImplementation()
{
    return (DOMImplementation*) DOMImplementationImpl::getDOMImplementationImpl();
}

bool DOMImplementation::loadDOMExceptionMsg
(
    const   DOMException::ExceptionCode  msgToLoad
    ,       XMLCh* const                 toFill
    , const unsigned int                 maxChars
)
{
    // load the text, the msgToLoad+XMLDOMMsgs::DOMEXCEPTION_ERRX+msgToLoad is the corresponding XMLDOMMsg Code
    return DOMImplementationImpl::getMsgLoader4DOM()->loadMsg(XMLDOMMsg::DOMEXCEPTION_ERRX+msgToLoad, toFill, maxChars);
}

bool DOMImplementation::loadDOMExceptionMsg
(
    const   DOMRangeException::RangeExceptionCode  msgToLoad
    ,       XMLCh* const                           toFill
    , const unsigned int                           maxChars
)
{
    // load the text, the XMLDOMMsgs::DOMRANGEEXCEPTION_ERRX+msgToLoad is the corresponding XMLDOMMsg Code
    return DOMImplementationImpl::getMsgLoader4DOM()->loadMsg(XMLDOMMsg::DOMRANGEEXCEPTION_ERRX+msgToLoad, toFill, maxChars);
}

// ------------------------------------------------------------
// DOMImplementationLS Virtual interface
// ------------------------------------------------------------
//Introduced in DOM Level 3
DOMBuilder* DOMImplementationImpl::createDOMBuilder(const short           mode,
                                                    const XMLCh* const,
                                                    MemoryManager* const  manager,
                                                    XMLGrammarPool* const gramPool)
{
    if (mode == DOMImplementationLS::MODE_ASYNCHRONOUS)
        throw DOMException(DOMException::NOT_SUPPORTED_ERR, 0, manager);

    return new (manager) DOMBuilderImpl(0, manager, gramPool);
}


DOMWriter* DOMImplementationImpl::createDOMWriter(MemoryManager* const manager)
{
    return new (manager) DOMWriterImpl(manager);
}

DOMInputSource* DOMImplementationImpl::createDOMInputSource()
{
    throw DOMException(DOMException::NOT_SUPPORTED_ERR, 0);

    return 0;
}


// ------------------------------------------------------------
// DOMImplementationSource Virtual interface
// ------------------------------------------------------------
DOMImplementation* DOMImplementationImpl::getDOMImplementation(const XMLCh* features) const
{
    DOMImplementation* impl = DOMImplementation::getImplementation();

    XMLStringTokenizer tokenizer(features, XMLPlatformUtils::fgMemoryManager);
    const XMLCh* feature = 0;

    while (feature || tokenizer.hasMoreTokens()) {

        if (!feature)
            feature = tokenizer.nextToken();

        const XMLCh* version = 0;
        const XMLCh* token = tokenizer.nextToken();

        if (token && XMLString::isDigit(token[0]))
            version = token;

        if (!impl->hasFeature(feature, version))
            return 0;

        if (!version)
            feature = token;
    }
    return impl;
}


XERCES_CPP_NAMESPACE_END