/**
 * Licensed to the University Corporation for Advanced Internet
 * Development, Inc. (UCAID) under one or more contributor license
 * agreements. See the NOTICE file distributed with this work for
 * additional information regarding copyright ownership.
 *
 * UCAID 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.
 */

/**
 * @file xmltooling/AbstractXMLObject.h
 *
 * An abstract implementation of XMLObject.
 */

#ifndef __xmltooling_abstractxmlobj_h__
#define __xmltooling_abstractxmlobj_h__

#include <xmltooling/logging.h>
#include <xmltooling/QName.h>
#include <xmltooling/XMLObject.h>

#include <memory>

#if defined (_MSC_VER)
    #pragma warning( push )
    #pragma warning( disable : 4250 4251 )
#endif

namespace xmltooling {

    class XMLTOOL_API DateTime;

    /**
     * An abstract implementation of XMLObject.
     * This is the primary concrete base class, and supplies basic namespace,
     * type, and parent handling. Most implementation classes should not
     * directly inherit from this class, but rather from the various mixins
     * that supply the rest of the XMLObject interface, as required.
     */
    class XMLTOOL_API AbstractXMLObject : public virtual XMLObject
    {
    public:
        virtual ~AbstractXMLObject();

        // Virtual function overrides.
        void detach();
        const QName& getElementQName() const;
        const std::set<Namespace>& getNamespaces() const;
        void addNamespace(const Namespace& ns) const;
        void removeNamespace(const Namespace& ns);
        const QName* getSchemaType() const;
        const XMLCh* getXMLID() const;
        xmlconstants::xmltooling_bool_t getNil() const;
        void nil(xmlconstants::xmltooling_bool_t value);
        bool hasParent() const;
        XMLObject* getParent() const;
        void setParent(XMLObject* parent);

     protected:
        /**
         * Constructor
         *
         * @param nsURI         the namespace of the element
         * @param localName     the local name of the XML element this Object represents
         * @param prefix        the namespace prefix to use
         * @param schemaType    the xsi:type to use
         */
        AbstractXMLObject(
            const XMLCh* nsURI=nullptr, const XMLCh* localName=nullptr, const XMLCh* prefix=nullptr, const QName* schemaType=nullptr
            );

        /** Copy constructor. */
        AbstractXMLObject(const AbstractXMLObject& src);

        /**
         * A helper function for derived classes, for assignment of strings.
         *
         * This 'normalizes' newString, and then if it is different from oldString,
         * it invalidates the DOM, frees the old string, and returns the new.
         * If not different, it frees the new string and just returns the old value.
         *
         * @param oldValue the current value
         * @param newValue the new value
         *
         * @return the value that should be assigned
         */
        XMLCh* prepareForAssignment(XMLCh* oldValue, const XMLCh* newValue);

        /**
         * A helper function for derived classes, for assignment of date/time data.
         *
         * It invalidates the DOM, frees the old object, and returns the new.
         *
         * @param oldValue the current value
         * @param newValue the new value
         *
         * @return the value that should be assigned
         */
        DateTime* prepareForAssignment(DateTime* oldValue, const DateTime* newValue);

        /**
         * A helper function for derived classes, for assignment of date/time data.
         *
         * It invalidates the DOM, frees the old object, and returns the new.
         *
         * @param oldValue the current value
         * @param newValue the epoch to assign as the new value
         * @param duration true iff the value is a duration rather than an absolute timestamp
         *
         * @return the value that should be assigned
         */
        DateTime* prepareForAssignment(DateTime* oldValue, time_t newValue, bool duration=false);

        /**
         * A helper function for derived classes, for assignment of date/time data.
         *
         * It invalidates the DOM, frees the old object, and returns the new.
         *
         * @param oldValue the current value
         * @param newValue the new value in string form
         * @param duration true iff the value is a duration rather than an absolute timestamp
         *
         * @return the value that should be assigned
         */
        DateTime* prepareForAssignment(DateTime* oldValue, const XMLCh* newValue, bool duration=false);

        /**
         * A helper function for derived classes, for assignment of QName data.
         *
         * It invalidates the DOM, frees the old object, and returns the new.
         *
         * @param oldValue the current value
         * @param newValue the new value
         *
         * @return the value that should be assigned
         */
        QName* prepareForAssignment(QName* oldValue, const QName* newValue);

        /**
         * A helper function for derived classes, for assignment of (singleton) XML objects.
         *
         * It is indifferent to whether either the old or the new version of the value is null.
         * This method will do a safe compare of the objects and will also invalidate the DOM if appropriate.
         * Note that since the new value (even if nullptr) is always returned, it may be more efficient
         * to discard the return value and just assign independently if a dynamic cast would be involved.
         *
         * @param oldValue current value
         * @param newValue proposed new value
         * @return the new value
         *
         * @throws XMLObjectException if the new child already has a parent.
         */
        XMLObject* prepareForAssignment(XMLObject* oldValue, XMLObject* newValue);

        /**
         * Set of namespaces associated with the object.
         */
        mutable std::set<Namespace> m_namespaces;

        /**
         * Logging object.
         */
        logging::Category& m_log;

        /**
         * Stores off xsi:schemaLocation attribute.
         */
        XMLCh* m_schemaLocation;

        /**
         * Stores off xsi:noNamespaceSchemaLocation attribute.
         */
        XMLCh* m_noNamespaceSchemaLocation;

        /**
         * Stores off xsi:nil attribute.
         */
        xmlconstants::xmltooling_bool_t m_nil;

    private:
        XMLObject* m_parent;
        QName m_elementQname;
        std::auto_ptr<QName> m_typeQname;
    };

};

#if defined (_MSC_VER)
    #pragma warning( pop )
#endif

#endif /* __xmltooling_abstractxmlobj_h__ */