/******************************************************************************
 * $Id: pngdataset.h 22f8ae3bf7bc3cccd970992655c63fc5254d3206 2018-04-08 20:13:05 +0200 Even Rouault $
 *
 * Project:  PNG Driver
 * Purpose:  Implement GDAL PNG Support
 * Author:   Frank Warmerdam, warmerda@home.com
 *
 ******************************************************************************
 * Copyright (c) 2000, Frank Warmerdam
 * Copyright (c) 2007-2014, Even Rouault <even dot rouault at mines-paris dot org>
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included
 * in all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
 * DEALINGS IN THE SOFTWARE.
 ******************************************************************************
 *
 * ISSUES:
 *  o CollectMetadata() will only capture TEXT chunks before the image
 *    data as the code is currently structured.
 *  o Interlaced images are read entirely into memory for use.  This is
 *    bad for large images.
 *  o Image reading is always strictly sequential.  Reading backwards will
 *    cause the file to be rewound, and access started again from the
 *    beginning.
 *  o 16 bit alpha values are not scaled by to eight bit.
 *
 */

#include "cpl_string.h"
#include "gdal_frmts.h"
#include "gdal_pam.h"

#ifdef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION
// Disabled for now since currently this only works for libpng 1.2
// libpng 1.6 requires additional includes. See #6928
// #define DISABLE_CRC_CHECK
#endif

#ifdef DISABLE_CRC_CHECK
// Needs to be defined before including png.h
#define PNG_INTERNAL
#endif

#include "png.h"

#include <csetjmp>

#include <algorithm>

#ifdef _MSC_VER
#  pragma warning(disable:4611)
#endif

/************************************************************************/
/* ==================================================================== */
/*                              PNGDataset                              */
/* ==================================================================== */
/************************************************************************/

class PNGRasterBand;

#ifdef _MSC_VER
#pragma warning( push )
// 'PNGDataset': structure was padded due to __declspec(align()) at line where
// we use `jmp_buf`.
#pragma warning( disable : 4324 )
#endif

class PNGDataset final: public GDALPamDataset
{
    friend class PNGRasterBand;

    VSILFILE        *fpImage;
    png_structp hPNG;
    png_infop   psPNGInfo;
    int         nBitDepth;
    int         nColorType;  // PNG_COLOR_TYPE_*
    int         bInterlaced;

    int         nBufferStartLine;
    int         nBufferLines;
    int         nLastLineRead;
    GByte      *pabyBuffer;

    GDALColorTable *poColorTable;

    int    bGeoTransformValid;
    double adfGeoTransform[6];

    void        CollectMetadata();

    int         bHasReadXMPMetadata;
    void        CollectXMPMetadata();

    CPLErr      LoadScanline( int );
    CPLErr      LoadInterlacedChunk( int );
    void        Restart();

    int         bHasTriedLoadWorldFile;
    void        LoadWorldFile();
    CPLString   osWldFilename;

    int         bHasReadICCMetadata;
    void        LoadICCProfile();

    static void WriteMetadataAsText(jmp_buf sSetJmpContext,
                                    png_structp hPNG, png_infop psPNGInfo,
                                    const char* pszKey, const char* pszValue);
    static GDALDataset *OpenStage2( GDALOpenInfo *, PNGDataset*& );

  public:
                 PNGDataset();
    virtual ~PNGDataset();

    static GDALDataset *Open( GDALOpenInfo * );
    static int          Identify( GDALOpenInfo * );
    static GDALDataset* CreateCopy( const char * pszFilename,
                                    GDALDataset *poSrcDS,
                                    int bStrict, char ** papszOptions,
                                    GDALProgressFunc pfnProgress,
                                    void * pProgressData );

    virtual char **GetFileList(void) override;

    virtual CPLErr GetGeoTransform( double * ) override;
    virtual void FlushCache( void ) override;

    virtual char      **GetMetadataDomainList() override;

    virtual char  **GetMetadata( const char * pszDomain = "" ) override;
    virtual const char *GetMetadataItem( const char * pszName,
                                         const char * pszDomain = nullptr ) override;

    virtual CPLErr      IRasterIO( GDALRWFlag, int, int, int, int,
                                   void *, int, int, GDALDataType,
                                   int, int *,
                                   GSpacing, GSpacing,
                                   GSpacing,
                                   GDALRasterIOExtraArg* psExtraArg ) override;

    jmp_buf     sSetJmpContext;  // Semi-private.

#ifdef SUPPORT_CREATE
    int        m_nBitDepth;
    GByte      *m_pabyBuffer;
    png_byte    *m_pabyAlpha;
    png_structp m_hPNG;
    png_infop   m_psPNGInfo;
    png_color   *m_pasPNGColors;
    VSILFILE        *m_fpImage;
    int    m_bGeoTransformValid;
    double m_adfGeoTransform[6];
    char        *m_pszFilename;
    int         m_nColorType;  // PNG_COLOR_TYPE_*

    virtual CPLErr SetGeoTransform( double * );
    static GDALDataset  *Create( const char* pszFilename,
                                int nXSize, int nYSize, int nBands,
                                GDALDataType, char** papszParmList );
  protected:
        CPLErr write_png_header();

#endif
};

#ifdef _MSC_VER
#pragma warning( pop )
#endif

/************************************************************************/
/* ==================================================================== */
/*                            PNGRasterBand                             */
/* ==================================================================== */
/************************************************************************/

class PNGRasterBand final: public GDALPamRasterBand
{
    friend class PNGDataset;

  public:

                   PNGRasterBand( PNGDataset *, int );
    virtual ~PNGRasterBand() {}

    virtual CPLErr IReadBlock( int, int, void * ) override;

    virtual GDALColorInterp GetColorInterpretation() override;
    virtual GDALColorTable *GetColorTable() override;
    CPLErr SetNoDataValue( double dfNewValue ) override;
    virtual double GetNoDataValue( int *pbSuccess = nullptr ) override;

    int         bHaveNoData;
    double      dfNoDataValue;

#ifdef SUPPORT_CREATE
    virtual CPLErr SetColorTable(GDALColorTable*);
    virtual CPLErr IWriteBlock( int, int, void * ) override;

  protected:
        int m_bBandProvided[5];
        void reset_band_provision_flags()
        {
            PNGDataset& ds = *reinterpret_cast<PNGDataset *>( poDS );

            for(size_t i = 0; i < static_cast<size_t>( ds.nBands ); i++)
                m_bBandProvided[i] = FALSE;
        }
#endif
};