/*

 * 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: XML256TableTranscoder.hpp 568078 2007-08-21 11:43:25Z amassari $

 */

#ifndef XML256TABLETRANSCODER_HPP

#define XML256TABLETRANSCODER_HPP

#include <xercesc/util/TransService.hpp>

XERCES_CPP_NAMESPACE_BEGIN

//

//  This class implements the functionality of a common type of transcoder

//  for an 8 bit, single byte encoding based on a set of 'to' and 'from'

//  translation tables. Actual derived classes are trivial and just have to

//  provide us with pointers to their tables and we do all the work.

//

class XMLUTIL_EXPORT XML256TableTranscoder : public XMLTranscoder

{

public :

    // -----------------------------------------------------------------------

    //  Public constructors and destructor

    // -----------------------------------------------------------------------

    virtual ~XML256TableTranscoder();

    // -----------------------------------------------------------------------

    //  The virtual transcoding interface

    // -----------------------------------------------------------------------

    virtual unsigned int transcodeFrom

    (

        const   XMLByte* const          srcData

        , const unsigned int            srcCount

        ,       XMLCh* const            toFill

        , const unsigned int            maxChars

        ,       unsigned int&           bytesEaten

        ,       unsigned char* const    charSizes

    );

    virtual unsigned int transcodeTo

    (

        const   XMLCh* const    srcData

        , const unsigned int    srcCount

        ,       XMLByte* const  toFill

        , const unsigned int    maxBytes

        ,       unsigned int&   charsEaten

        , const UnRepOpts       options

    );

    virtual bool canTranscodeTo

    (

        const   unsigned int    toCheck

    )   const;

protected :

    // -----------------------------------------------------------------------

    //  Hidden constructors

    // -----------------------------------------------------------------------

    XML256TableTranscoder

    (

        const   XMLCh* const                        encodingName

        , const unsigned int                        blockSize

        , const XMLCh* const                        fromTable

        , const XMLTransService::TransRec* const    toTable

        , const unsigned int                        toTableSize

        , MemoryManager* const manager = XMLPlatformUtils::fgMemoryManager

    );

    // -----------------------------------------------------------------------

    //  Protected helper methods

    // -----------------------------------------------------------------------

    XMLByte xlatOneTo

    (

        const   XMLCh       toXlat

    )   const;

private :

    // -----------------------------------------------------------------------

    //  Unimplemented constructors and operators

    // -----------------------------------------------------------------------

    XML256TableTranscoder();

    XML256TableTranscoder(const XML256TableTranscoder&);

    XML256TableTranscoder& operator=(const XML256TableTranscoder&);

    // -----------------------------------------------------------------------

    //  Private data members

    //

    //  fFromTable

    //      This is the 'from' table that we were given during construction.

    //      It is a 256 entry table of XMLCh chars. Each entry is the

    //      Unicode code point for the external encoding point of that value.

    //      So fFromTable[N] is the Unicode translation of code point N of

    //      the source encoding.

    //

    //      We don't own this table, we just refer to it. It is assumed that

    //      the table is static, for performance reasons.

    //

    //  fToSize

    //      The 'to' table is variable sized. This indicates how many records

    //      are in it.

    //

    //  fToTable

    //      This is a variable sized table of TransRec structures. It must

    //      be sorted by the intCh field, i.e. the XMLCh field. It is searched

    //      binarily to find the record for a particular Unicode char. Then

    //      that record's extch field is the translation record.

    //

    //      We don't own this table, we just refer to it. It is assumed that

    //      the table is static, for performance reasons.

    //

    //      NOTE: There may be dups of the extCh field, since there might be

    //      multiple Unicode code points which map to the same external code

    //      point. Normally this won't happen, since the parser assumes that

    //      internalization is normalized, but we have to be prepared to do

    //      the right thing if some client code gives us non-normalized data

    //      itself.

    // -----------------------------------------------------------------------

    const XMLCh*                        fFromTable;

    unsigned int                        fToSize;

    const XMLTransService::TransRec*    fToTable;

};

XERCES_CPP_NAMESPACE_END

#endif