// ***************************************************************** -*- C++ -*-

/*

 * Copyright (C) 2004-2018 Exiv2 authors

 * This program is part of the Exiv2 distribution.

 *

 * This program is free software; you can redistribute it and/or

 * modify it under the terms of the GNU General Public License

 * as published by the Free Software Foundation; either version 2

 * of the License, or (at your option) any later version.

 *

 * This program is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

 * GNU General Public License for more details.

 *

 * You should have received a copy of the GNU General Public License

 * along with this program; if not, write to the Free Software

 * Foundation, Inc., 51 Franklin Street, 5th Floor, Boston, MA 02110-1301 USA.

 */

/*

  File:      tgaimage.cpp

  Author(s): Marco Piovanelli, Ovolab (marco)

  History:   05-Mar-2007, marco: created

 */

// *****************************************************************************

// included header files

#include "config.h"

#include "tgaimage.hpp"

#include "image.hpp"

#include "basicio.hpp"

#include "error.hpp"

#include "futils.hpp"

// + standard includes

#include <string>

#include <cstring>

#include <iostream>

// *****************************************************************************

// class member definitions

namespace Exiv2 {

    TgaImage::TgaImage(BasicIo::AutoPtr io)

        : Image(ImageType::tga, mdNone, io)

    {

    } // TgaImage::TgaImage

    std::string TgaImage::mimeType() const

    {

        return "image/targa";

    }

    void TgaImage::setExifData(const ExifData& /*exifData*/)

    {

        // Todo: implement me!

        throw(Error(kerInvalidSettingForImage, "Exif metadata", "TGA"));

    }

    void TgaImage::setIptcData(const IptcData& /*iptcData*/)

    {

        // Todo: implement me!

        throw(Error(kerInvalidSettingForImage, "IPTC metadata", "TGA"));

    }

    void TgaImage::setComment(const std::string& /*comment*/)

    {

        // not supported

        throw(Error(kerInvalidSettingForImage, "Image comment", "TGA"));

    }

    void TgaImage::readMetadata()

    {

#ifdef EXIV2_DEBUG_MESSAGES

        std::cerr << "Exiv2::TgaImage::readMetadata: Reading TARGA file " << io_->path() << "\n";

#endif

        if (io_->open() != 0)

        {

            throw Error(kerDataSourceOpenFailed, io_->path(), strError());

        }

        IoCloser closer(*io_);

        // Ensure that this is the correct image type

        if (!isTgaType(*io_, false))

        {

            if (io_->error() || io_->eof()) throw Error(kerFailedToReadImageData);

            throw Error(kerNotAnImage, "TGA");

        }

        clearMetadata();

        /*

          The TARGA header goes as follows -- all numbers are in little-endian byte order:

          offset  length   name                     description

          ======  =======  =======================  ===========

           0      1 byte   ID length                length of image ID (0 to 255)

           1      1 byte   color map type           0 = no color map; 1 = color map included

           2      1 byte   image type                0 = no image;

                                                     1 = uncompressed color-mapped;

                                                     2 = uncompressed true-color;

                                                     3 = uncompressed black-and-white;

                                                     9 = RLE-encoded color mapped;

                                                    10 = RLE-encoded true-color;

                                                    11 = RLE-encoded black-and-white

           3      5 bytes  color map specification

           8      2 bytes  x-origin of image

          10      2 bytes  y-origin of image

          12      2 bytes  image width

          14      2 bytes  image height

          16      1 byte   pixel depth

          17      1 byte   image descriptor

        */

        byte buf[18];

        if (io_->read(buf, sizeof(buf)) == sizeof(buf))

        {

            pixelWidth_ = getShort(buf + 12, littleEndian);

            pixelHeight_ = getShort(buf + 14, littleEndian);

        }

    } // TgaImage::readMetadata

    void TgaImage::writeMetadata()

    {

        // Todo: implement me!

        throw(Error(kerWritingImageFormatUnsupported, "TGA"));

    } // TgaImage::writeMetadata

    // *************************************************************************

    // free functions

    Image::AutoPtr newTgaInstance(BasicIo::AutoPtr io, bool /*create*/)

    {

        Image::AutoPtr image(new TgaImage(io));

        if (!image->good())

        {

            image.reset();

        }

        return image;

    }

    bool isTgaType(BasicIo& iIo, bool /*advance*/)

    {

        // not all TARGA files have a signature string, so first just try to match the file name extension

#ifdef EXV_UNICODE_PATH

        std::wstring wpath = iIo.wpath();

        if(   wpath.rfind(EXV_WIDEN(".tga")) != std::wstring::npos

           || wpath.rfind(EXV_WIDEN(".TGA")) != std::wstring::npos) {

            return true;

        }

#else

        std::string path = iIo.path();

        if(   path.rfind(".tga") != std::string::npos

           || path.rfind(".TGA") != std::string::npos) {

            return true;

        }

#endif

        byte buf[26];

        long curPos = iIo.tell();

        iIo.seek(-26, BasicIo::end);

        if (iIo.error() || iIo.eof())

        {

            return false;

        }

        iIo.read(buf, sizeof(buf));

        if (iIo.error())

        {

            return false;

        }

        // some TARGA files, but not all, have a signature string at the end

        bool matched = (memcmp(buf + 8, "TRUEVISION-XFILE", 16) == 0);

        iIo.seek(curPos, BasicIo::beg);

        return matched;

    }

}                                       // namespace Exiv2