/*
 * Copyright (c) 1999-2000, Eric Moon.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions, and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions, and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * 3. The name of the author may not be used to endorse or promote products
 *    derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR "AS IS" AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF TITLE, NON-INFRINGEMENT, MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR
 * TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */


// FlatMessageIO.h
// * PURPOSE
//   Efficient export/import of BMessages to and from
//   XML using the Cortex persistence library.
//   Messages are stored in flattened form.
// * HISTORY
//   e.moon             6jul99          Begun.
//
// Example:
//
// <flat-BMessage
//   encoding = 'base64'>
//   nKJNFBlkn3lknbxlkfnbLKN/lknlknlDSLKn3lkn3l2k35234ljk234
//   lkdsg23823nlknsdlkbNDSLKBNlkn3lk23n4kl23n423lknLKENL+==
// </flat-BMessage>

#ifndef __FlatMessageIO_H__
#define __FlatMessageIO_H__

#include <Message.h>
#include <String.h>
#include "XML.h"

#include "cortex_defs.h"
__BEGIN_CORTEX_NAMESPACE

class FlatMessageIO :
        public          IPersistent {

public:                                 // *** ctor/dtor/accessor
        virtual ~FlatMessageIO();

        FlatMessageIO();
        
        // When given a message to export, this object does NOT take
        // responsibility for deleting it.  It will, however, handle
        // deletion of an imported BMessage.  
        
        FlatMessageIO(const BMessage* message);
        void setMessage(BMessage* message);     
        
        // Returns 0 if no message has been set, and if no message has
        // been imported.
        
        const BMessage* message() const { return m_message; }
        
        // Returns true if the message will be automatically deleted.
        
        bool ownsMessage() const { return m_ownMessage; }

public:                                 // *** static setup method
        // call this method to install hooks for the tags needed by
        // FlatMessageIO into the given document type
        static void AddTo(XML::DocumentType* pDocType);
        
public:                                 // *** XML formatting
        static const char* const                        s_element;
        static const uint16                                     s_encodeToMax                   = 72;
        static const uint16                                     s_encodeToMin                   = 24;

public:                                 // *** IPersistent impl.

//      virtual void xmlExport(
//              ostream&                                        stream,
//              ExportContext&          context) const;

        // EXPORT:
        
        void xmlExportBegin(
                ExportContext& context) const;
                
        void xmlExportAttributes(
                ExportContext& context) const;
        
        void xmlExportContent(
                ExportContext& context) const;
        
        void xmlExportEnd(
                ExportContext& context) const;


        // IMPORT:

        virtual void xmlImportBegin(
                ImportContext&          context);

        virtual void xmlImportAttribute(
                const char*                                     key,
                const char*                                     value,
                ImportContext&          context);
        
        virtual void xmlImportContent(
                const char*                                     data,
                uint32                                          length,
                ImportContext&          context);
        
        virtual void xmlImportChild(
                IPersistent*                    child,
                ImportContext&          context);
                        
        virtual void xmlImportComplete(
                ImportContext&          context);
                
private:                                        // *** members
        bool                                            m_ownMessage;
        BMessage*                       m_message;

        // encoded data is cached here during the import process        
        BString                         m_base64Data;
};

__END_CORTEX_NAMESPACE

#endif /*__FlatMessageIO_H__*/