// ***************************************************************** -*- C++ -*-
/*
 * Copyright (C) 2004-2015 Andreas Huggel <ahuggel@gmx.net>
 *
 * 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:      epsimage.cpp
  Version:   $Rev: 2455 $
  Author(s): Michael Ulbrich (mul) <mul@rentapacs.de>
             Volker Grabsch (vog) <vog@notjusthosting.com>
  History:   7-Mar-2011, vog: created
 */
// *****************************************************************************
#include "rcsid_int.hpp"
EXIV2_RCSID("@(#) $Id: epsimage.cpp $")

// included header files
#include "config.h"

#include "epsimage.hpp"
#include "image.hpp"
#include "basicio.hpp"
#include "error.hpp"
#include "futils.hpp"

// + standard includes
#include <algorithm>
#include <cassert>
#include <climits>
#include <cstring>
#include <iostream>
#include <sstream>
#include <string>

// *****************************************************************************
namespace {

    using namespace Exiv2;

    // signature of DOS EPS
    const std::string dosEpsSignature = "\xC5\xD0\xD3\xC6";

    // first line of EPS
    const std::string epsFirstLine[] = {
        "%!PS-Adobe-3.0 EPSF-3.0",
        "%!PS-Adobe-3.0 EPSF-3.0 ", // OpenOffice
        "%!PS-Adobe-3.1 EPSF-3.0",  // Illustrator
    };

    // blank EPS file
    const std::string epsBlank = "%!PS-Adobe-3.0 EPSF-3.0\n"
                                 "%%BoundingBox: 0 0 0 0\n";

    // list of all valid XMP headers
    const std::string xmpHeaders[] = {

        // We do not enforce the trailing "?>" here, because the XMP specification
        // permits additional attributes after begin="..." and id="...".

        // normal headers
        "<?xpacket begin=\"\xef\xbb\xbf\" id=\"W5M0MpCehiHzreSzNTczkc9d\"",
        "<?xpacket begin=\"\xef\xbb\xbf\" id='W5M0MpCehiHzreSzNTczkc9d'",
        "<?xpacket begin='\xef\xbb\xbf' id=\"W5M0MpCehiHzreSzNTczkc9d\"",
        "<?xpacket begin='\xef\xbb\xbf' id='W5M0MpCehiHzreSzNTczkc9d'",

        // deprecated headers (empty begin attribute, UTF-8 only)
        "<?xpacket begin=\"\" id=\"W5M0MpCehiHzreSzNTczkc9d\"",
        "<?xpacket begin=\"\" id='W5M0MpCehiHzreSzNTczkc9d'",
        "<?xpacket begin='' id=\"W5M0MpCehiHzreSzNTczkc9d\"",
        "<?xpacket begin='' id='W5M0MpCehiHzreSzNTczkc9d'",
    };

    // list of all valid XMP trailers
    struct XmpTrailer {
        std::string trailer;
        bool readOnly;
    };

    const XmpTrailer xmpTrailers[] = {

        // We do not enforce the trailing "?>" here, because the XMP specification
        // permits additional attributes after end="...".

        {"<?xpacket end=\"r\"", true},
        {"<?xpacket end='r'",   true},
        {"<?xpacket end=\"w\"", false},
        {"<?xpacket end='w'",   false},
    };

    // closing part of all valid XMP trailers
    const std::string xmpTrailerEnd = "?>";

    //! Write data into temp file, taking care of errors
    void writeTemp(BasicIo& tempIo, const byte* data, size_t size)
    {
        if (size == 0) return;
        if (tempIo.write(data, static_cast<long>(size)) != static_cast<long>(size)) {
            #ifndef SUPPRESS_WARNINGS
            EXV_WARNING << "Failed to write to temporary file.\n";
            #endif
            throw Error(21);
        }
    }

    //! Write data into temp file, taking care of errors
    void writeTemp(BasicIo& tempIo, const std::string &data)
    {
        writeTemp(tempIo, reinterpret_cast<const byte*>(data.data()), data.size());
    }

    //! Get the current write position of temp file, taking care of errors
    uint32_t posTemp(BasicIo& tempIo)
    {
        const long pos = tempIo.tell();
        if (pos == -1) {
            #ifndef SUPPRESS_WARNINGS
            EXV_WARNING << "Internal error while determining current write position in temporary file.\n";
            #endif
            throw Error(21);
        }
        return static_cast<uint32_t>(pos);
    }

    //! Check whether a string has a certain beginning
    bool startsWith(const std::string& s, const std::string& start)
    {
        return s.size() >= start.size() && memcmp(s.data(), start.data(), start.size()) == 0;
    }

    //! Check whether a string contains only white space characters
    bool onlyWhitespaces(const std::string& s)
    {
        // According to the DSC 3.0 specification, 4.4 Parsing Rules,
        // only spaces and tabs are considered to be white space characters.
        return s.find_first_not_of(" \t") == std::string::npos;
    }

    //! Read the next line of a buffer, allow for changing line ending style
    size_t readLine(std::string& line, const byte* data, size_t startPos, size_t size)
    {
        line.clear();
        size_t pos = startPos;
        // step through line
        while (pos < size && data[pos] != '\r' && data[pos] != '\n') {
            line += data[pos];
            pos++;
        }
        // skip line ending, if present
        if (pos >= size) return pos;
        pos++;
        if (pos >= size) return pos;
        if (data[pos - 1] == '\r' && data[pos] == '\n') pos++;
        return pos;
    }

    //! Read the previous line of a buffer, allow for changing line ending style
    size_t readPrevLine(std::string& line, const byte* data, size_t startPos, size_t size)
    {
        line.clear();
        size_t pos = startPos;
        if (pos > size) return pos;
        // skip line ending of previous line, if present
        if (pos <= 0) return pos;
        if (data[pos - 1] == '\r' || data[pos - 1] == '\n') {
            pos--;
            if (pos <= 0) return pos;
            if (data[pos - 1] == '\r' && data[pos] == '\n') {
                pos--;
                if (pos <= 0) return pos;
            }
        }
        // step through previous line
        while (pos >= 1 && data[pos - 1] != '\r' && data[pos - 1] != '\n') {
            pos--;
            line += data[pos];
        }
        std::reverse(line.begin(), line.end());
        return pos;
    }

    //! Find an XMP block
    void findXmp(size_t& xmpPos, size_t& xmpSize, const byte* data, size_t startPos, size_t size, bool write)
    {
        // search for valid XMP header
        xmpSize = 0;
        for (xmpPos = startPos; xmpPos < size; xmpPos++) {
            if (data[xmpPos] != '\x00' && data[xmpPos] != '<') continue;
            for (size_t i = 0; i < (sizeof xmpHeaders) / (sizeof *xmpHeaders); i++) {
                const std::string &header = xmpHeaders[i];
                if (xmpPos + header.size() > size) continue;
                if (memcmp(data + xmpPos, header.data(), header.size()) != 0) continue;
                #ifdef DEBUG
                EXV_DEBUG << "findXmp: Found XMP header at position: " << xmpPos << "\n";
                #endif

                // search for valid XMP trailer
                for (size_t trailerPos = xmpPos + header.size(); trailerPos < size; trailerPos++) {
                    if (data[xmpPos] != '\x00' && data[xmpPos] != '<') continue;
                    for (size_t j = 0; j < (sizeof xmpTrailers) / (sizeof *xmpTrailers); j++) {
                        const std::string &trailer = xmpTrailers[j].trailer;
                        const bool readOnly = xmpTrailers[j].readOnly;

                        if (trailerPos + trailer.size() > size) continue;
                        if (memcmp(data + trailerPos, trailer.data(), trailer.size()) != 0) continue;
                        #ifdef DEBUG
                        EXV_DEBUG << "findXmp: Found XMP trailer at position: " << trailerPos << "\n";
                        #endif

                        if (readOnly) {
                            #ifndef SUPPRESS_WARNINGS
                            EXV_WARNING << "Unable to handle read-only XMP metadata yet. Please provide your "
                                           "sample EPS file to the Exiv2 project: http://dev.exiv2.org/projects/exiv2\n";
                            #endif
                            throw Error(write ? 21 : 14);
                        }

                        // search for end of XMP trailer
                        for (size_t trailerEndPos = trailerPos + trailer.size(); trailerEndPos + xmpTrailerEnd.size() <= size; trailerEndPos++) {
                            if (memcmp(data + trailerEndPos, xmpTrailerEnd.data(), xmpTrailerEnd.size()) == 0) {
                                xmpSize = (trailerEndPos + xmpTrailerEnd.size()) - xmpPos;
                                return;
                            }
                        }
                        #ifndef SUPPRESS_WARNINGS
                        EXV_WARNING << "Found XMP header but incomplete XMP trailer.\n";
                        #endif
                        throw Error(write ? 21 : 14);
                    }
                }
                #ifndef SUPPRESS_WARNINGS
                EXV_WARNING << "Found XMP header but no XMP trailer.\n";
                #endif
                throw Error(write ? 21 : 14);
            }
        }
    }

    //! Unified implementation of reading and writing EPS metadata
    void readWriteEpsMetadata(BasicIo& io, std::string& xmpPacket, NativePreviewList& nativePreviews, bool write)
    {
        // open input file
        if (io.open() != 0) {
            throw Error(9, io.path(), strError());
        }
        IoCloser closer(io);

        // read from input file via memory map
        const byte *data = io.mmap();

        // default positions and sizes
        const size_t size = static_cast<size_t>(io.size());
        size_t posEps = 0;
        size_t posEndEps = size;
        uint32_t posWmf = 0;
        uint32_t sizeWmf = 0;
        uint32_t posTiff = 0;
        uint32_t sizeTiff = 0;

        // check for DOS EPS
        const bool dosEps = (size >= dosEpsSignature.size() && memcmp(data, dosEpsSignature.data(), dosEpsSignature.size()) == 0);
        if (dosEps) {
            #ifdef DEBUG
            EXV_DEBUG << "readWriteEpsMetadata: Found DOS EPS signature\n";
            #endif
            if (size < 30) {
                #ifndef SUPPRESS_WARNINGS
                EXV_WARNING << "Premature end of file after DOS EPS signature.\n";
                #endif
                throw Error(write ? 21 : 14);
            }
            posEps    = getULong(data +  4, littleEndian);
            posEndEps = getULong(data +  8, littleEndian) + posEps;
            posWmf    = getULong(data + 12, littleEndian);
            sizeWmf   = getULong(data + 16, littleEndian);
            posTiff   = getULong(data + 20, littleEndian);
            sizeTiff  = getULong(data + 24, littleEndian);
            const uint16_t checksum = getUShort(data + 28, littleEndian);
            #ifdef DEBUG
            EXV_DEBUG << "readWriteEpsMetadata: EPS section at position " << posEps << ", size " << (posEndEps - posEps) << "\n";
            EXV_DEBUG << "readWriteEpsMetadata: WMF section at position " << posWmf << ", size " << sizeWmf << "\n";
            EXV_DEBUG << "readWriteEpsMetadata: TIFF section at position " << posTiff << ", size " << sizeTiff << "\n";
            #endif
            if (checksum != 0xFFFF) {
                #ifdef DEBUG
                EXV_DEBUG << "readWriteEpsMetadata: DOS EPS checksum is not FFFF\n";
                #endif
            }
            if (!((posWmf == 0 && sizeWmf == 0) || (posTiff == 0 && sizeTiff == 0))) {
                #ifndef SUPPRESS_WARNINGS
                EXV_WARNING << "DOS EPS file has both WMF and TIFF section. Only one of those is allowed.\n";
                #endif
                if (write) throw Error(21);
            }
            if (sizeWmf == 0 && sizeTiff == 0) {
                #ifndef SUPPRESS_WARNINGS
                EXV_WARNING << "DOS EPS file has neither WMF nor TIFF section. Exactly one of those is required.\n";
                #endif
                if (write) throw Error(21);
            }
            if (posEps < 30 || posEndEps > size) {
                #ifndef SUPPRESS_WARNINGS
                EXV_WARNING << "DOS EPS file has invalid position (" << posEps << ") or size (" << (posEndEps - posEps) << ") for EPS section.\n";
                #endif
                throw Error(write ? 21 : 14);
            }
            if (sizeWmf != 0 && (posWmf < 30 || posWmf + sizeWmf > size)) {
                #ifndef SUPPRESS_WARNINGS
                EXV_WARNING << "DOS EPS file has invalid position (" << posWmf << ") or size (" << sizeWmf << ") for WMF section.\n";
                #endif
                if (write) throw Error(21);
            }
            if (sizeTiff != 0 && (posTiff < 30 || posTiff + sizeTiff > size)) {
                #ifndef SUPPRESS_WARNINGS
                EXV_WARNING << "DOS EPS file has invalid position (" << posTiff << ") or size (" << sizeTiff << ") for TIFF section.\n";
                #endif
                if (write) throw Error(21);
            }
        }

        // check first line
        std::string firstLine;
        const size_t posSecondLine = readLine(firstLine, data, posEps, posEndEps);
        #ifdef DEBUG
        EXV_DEBUG << "readWriteEpsMetadata: First line: " << firstLine << "\n";
        #endif
        bool matched = false;
        for (size_t i = 0; !matched && i < (sizeof epsFirstLine) / (sizeof *epsFirstLine); i++) {
            matched = (firstLine == epsFirstLine[i]);
        }
        if (!matched) {
            throw Error(3, "EPS");
        }

        // determine line ending style of the first line
        if (posSecondLine >= posEndEps) {
            #ifndef SUPPRESS_WARNINGS
            EXV_WARNING << "Premature end of file after first line.\n";
            #endif
            throw Error(write ? 21 : 14);
        }
        const std::string lineEnding(reinterpret_cast<const char*>(data + posEps + firstLine.size()), posSecondLine - (posEps + firstLine.size()));
        #ifdef DEBUG
        if (lineEnding == "\n") {
            EXV_DEBUG << "readWriteEpsMetadata: Line ending style: Unix (LF)\n";
        } else if (lineEnding == "\r") {
            EXV_DEBUG << "readWriteEpsMetadata: Line ending style: Mac (CR)\n";
        } else if (lineEnding == "\r\n") {
            EXV_DEBUG << "readWriteEpsMetadata: Line ending style: DOS (CR LF)\n";
        } else {
            EXV_DEBUG << "readWriteEpsMetadata: Line ending style: (unknown)\n";
        }
        #endif

        // scan comments
        size_t posLanguageLevel = posEndEps;
        size_t posContainsXmp = posEndEps;
        size_t posPages = posEndEps;
        size_t posExiv2Version = posEndEps;
        size_t posExiv2Website = posEndEps;
        size_t posEndComments = posEndEps;
        size_t posAi7Thumbnail = posEndEps;
        size_t posAi7ThumbnailEndData = posEndEps;
        size_t posBeginPhotoshop = posEndEps;
        size_t posEndPhotoshop = posEndEps;
        size_t posPage = posEndEps;
        size_t posBeginPageSetup = posEndEps;
        size_t posEndPageSetup = posEndEps;
        size_t posPageTrailer = posEndEps;
        size_t posEof = posEndEps;
        std::vector<std::pair<size_t, size_t> > removableEmbeddings;
        unsigned int depth = 0;
        const unsigned int maxDepth = UINT_MAX;
        bool illustrator8 = false;
        bool corelDraw = false;
        bool implicitPage = false;
        bool implicitPageSetup = false;
        bool implicitPageTrailer = false;
        bool inDefaultsPreviewPrologSetup = false;
        bool inRemovableEmbedding = false;
        std::string removableEmbeddingEndLine;
        unsigned int removableEmbeddingsWithUnmarkedTrailer = 0;
        for (size_t pos = posEps; pos < posEof;) {
            const size_t startPos = pos;
            std::string line;
            pos = readLine(line, data, startPos, posEndEps);
            #ifdef DEBUG
            bool significantLine = true;
            #endif
            // nested documents
            if (posPage == posEndEps && (startsWith(line, "%%IncludeDocument:") || startsWith(line, "%%BeginDocument:"))) {
                #ifndef SUPPRESS_WARNINGS
                EXV_WARNING << "Nested document at invalid position: " << startPos << "\n";
                #endif
                throw Error(write ? 21 : 14);
            } else if (startsWith(line, "%%BeginDocument:")) {
                if (depth == maxDepth) {
                    #ifndef SUPPRESS_WARNINGS
                    EXV_WARNING << "Document too deeply nested at position: " << startPos << "\n";
                    #endif
                    throw Error(write ? 21 : 14);
                }
                depth++;
            } else if (startsWith(line, "%%EndDocument")) {
                if (depth == 0) {
                    #ifndef SUPPRESS_WARNINGS
                    EXV_WARNING << "Unmatched EndDocument at position: " << startPos << "\n";
                    #endif
                    throw Error(write ? 21 : 14);
                }
                depth--;
            } else {
                #ifdef DEBUG
                significantLine = false;
                #endif
            }
            #ifdef DEBUG
            if (significantLine) {
                EXV_DEBUG << "readWriteEpsMetadata: Found significant line \"" << line << "\" at position: " << startPos << "\n";
            }
            significantLine = true;
            #endif
            if (depth != 0) continue;
            // explicit "Begin" comments
            if (startsWith(line, "%%BeginPreview:")) {
                inDefaultsPreviewPrologSetup = true;
            } else if (line == "%%BeginDefaults") {
                inDefaultsPreviewPrologSetup = true;
            } else if (line == "%%BeginProlog") {
                inDefaultsPreviewPrologSetup = true;
            } else if (line == "%%BeginSetup") {
                inDefaultsPreviewPrologSetup = true;
            } else if (posPage == posEndEps && startsWith(line, "%%Page:")) {
                posPage = startPos;
            } else if (posPage != posEndEps && startsWith(line, "%%Page:")) {
                if (implicitPage) {
                    #ifndef SUPPRESS_WARNINGS
                    EXV_WARNING << "Page at position " << startPos << " conflicts with implicit page at position: " << posPage << "\n";
                    #endif
                    throw Error(write ? 21 : 14);
                }
                #ifndef SUPPRESS_WARNINGS
                EXV_WARNING << "Unable to handle multiple PostScript pages. Found second page at position: " << startPos << "\n";
                #endif
                throw Error(write ? 21 : 14);
            } else if (line == "%%BeginPageSetup") {
                posBeginPageSetup = startPos;
            } else if (!inRemovableEmbedding && line == "%Exiv2BeginXMP: Before %%EndPageSetup") {
                inRemovableEmbedding = true;
                removableEmbeddings.push_back(std::make_pair(startPos, startPos));
                removableEmbeddingEndLine = "%Exiv2EndXMP";
            } else if (!inRemovableEmbedding && line == "%Exiv2BeginXMP: After %%PageTrailer") {
                inRemovableEmbedding = true;
                removableEmbeddings.push_back(std::make_pair(startPos, startPos));
                removableEmbeddingEndLine = "%Exiv2EndXMP";
            } else if (!inRemovableEmbedding && line == "%ADOBeginClientInjection: PageSetup End \"AI11EPS\"") {
                inRemovableEmbedding = true;
                removableEmbeddings.push_back(std::make_pair(startPos, startPos));
                removableEmbeddingEndLine = "%ADOEndClientInjection: PageSetup End \"AI11EPS\"";
            } else if (!inRemovableEmbedding && line == "%ADOBeginClientInjection: PageTrailer Start \"AI11EPS\"") {
                inRemovableEmbedding = true;
                removableEmbeddings.push_back(std::make_pair(startPos, startPos));
                removableEmbeddingEndLine = "%ADOEndClientInjection: PageTrailer Start \"AI11EPS\"";
            } else if (!inRemovableEmbedding && line == "%begin_xml_code") {
                inRemovableEmbedding = true;
                removableEmbeddings.push_back(std::make_pair(startPos, startPos));
                removableEmbeddingEndLine = "%end_xml_code";
                removableEmbeddingsWithUnmarkedTrailer++;
            } else {
                #ifdef DEBUG
                significantLine = false;
                #endif
            }
            #ifdef DEBUG
            if (significantLine) {
                EXV_DEBUG << "readWriteEpsMetadata: Found significant line \"" << line << "\" at position: " << startPos << "\n";
            }
            significantLine = true;
            #endif
            // implicit comments
            if (line == "%%EOF" || line == "%begin_xml_code" || !(line.size() >= 2 && line[0] == '%' && '\x21' <= line[1] && line[1] <= '\x7e')) {
                if (posEndComments == posEndEps) {
                    posEndComments = startPos;
                    #ifdef DEBUG
                    EXV_DEBUG << "readWriteEpsMetadata: Found implicit EndComments at position: " << startPos << "\n";
                    #endif
                }
            }
            if (posPage == posEndEps && posEndComments != posEndEps && !inDefaultsPreviewPrologSetup && !inRemovableEmbedding && !onlyWhitespaces(line)) {
                posPage = startPos;
                implicitPage = true;
                #ifdef DEBUG
                EXV_DEBUG << "readWriteEpsMetadata: Found implicit Page at position: " << startPos << "\n";
                #endif
            }
            if (posBeginPageSetup == posEndEps && (implicitPage || (posPage != posEndEps && !inRemovableEmbedding && line.size() >= 1 && line[0] != '%'))) {
                posBeginPageSetup = startPos;
                implicitPageSetup = true;
                #ifdef DEBUG
                EXV_DEBUG << "readWriteEpsMetadata: Found implicit BeginPageSetup at position: " << startPos << "\n";
                #endif
            }
            if (posEndPageSetup == posEndEps && implicitPageSetup && !inRemovableEmbedding && line.size() >= 1 && line[0] != '%') {
                posEndPageSetup = startPos;
                #ifdef DEBUG
                EXV_DEBUG << "readWriteEpsMetadata: Found implicit EndPageSetup at position: " << startPos << "\n";
                #endif
            }
            if (line.size() >= 1 && line[0] != '%') continue; // performance optimization
            if (line == "%%EOF" || line == "%%Trailer" || line == "%%PageTrailer") {
                if (posBeginPageSetup == posEndEps) {
                    posBeginPageSetup = startPos;
                    implicitPageSetup = true;
                    #ifdef DEBUG
                    EXV_DEBUG << "readWriteEpsMetadata: Found implicit BeginPageSetup at position: " << startPos << "\n";
                    #endif
                }
                if (posEndPageSetup == posEndEps) {
                    posEndPageSetup = startPos;
                    implicitPageSetup = true;
                    #ifdef DEBUG
                    EXV_DEBUG << "readWriteEpsMetadata: Found implicit EndPageSetup at position: " << startPos << "\n";
                    #endif
                }
            }
            if (line == "%%EOF" || line == "%%Trailer") {
                if (posPageTrailer == posEndEps) {
                    posPageTrailer = startPos;
                    implicitPageTrailer = true;
                    #ifdef DEBUG
                    EXV_DEBUG << "readWriteEpsMetadata: Found implicit PageTrailer at position: " << startPos << "\n";
                    #endif
                }
            }
            // remaining explicit comments
            if (posEndComments == posEndEps && posLanguageLevel == posEndEps && startsWith(line, "%%LanguageLevel:")) {
                posLanguageLevel = startPos;
            } else if (posEndComments == posEndEps && posContainsXmp == posEndEps && startsWith(line, "%ADO_ContainsXMP:")) {
                posContainsXmp = startPos;
            } else if (posEndComments == posEndEps && posPages == posEndEps && startsWith(line, "%%Pages:")) {
                posPages = startPos;
            } else if (posEndComments == posEndEps && posExiv2Version == posEndEps && startsWith(line, "%Exiv2Version:")) {
                posExiv2Version = startPos;
            } else if (posEndComments == posEndEps && posExiv2Website == posEndEps && startsWith(line, "%Exiv2Website:")) {
                posExiv2Website = startPos;
            } else if (posEndComments == posEndEps && startsWith(line, "%%Creator: Adobe Illustrator") && firstLine == "%!PS-Adobe-3.0 EPSF-3.0") {
                illustrator8 = true;
            } else if (posEndComments == posEndEps && startsWith(line, "%AI7_Thumbnail:")) {
                posAi7Thumbnail = startPos;
            } else if (posEndComments == posEndEps && posAi7Thumbnail != posEndEps && posAi7ThumbnailEndData == posEndEps && line == "%%EndData") {
                posAi7ThumbnailEndData = startPos;
            } else if (posEndComments == posEndEps && line == "%%EndComments") {
                posEndComments = startPos;
            } else if (inDefaultsPreviewPrologSetup && startsWith(line, "%%BeginResource: procset wCorel")) {
                corelDraw = true;
            } else if (line == "%%EndPreview") {
                inDefaultsPreviewPrologSetup = false;
            } else if (line == "%%EndDefaults") {
                inDefaultsPreviewPrologSetup = false;
            } else if (line == "%%EndProlog") {
                inDefaultsPreviewPrologSetup = false;
            } else if (line == "%%EndSetup") {
                inDefaultsPreviewPrologSetup = false;
            } else if (posEndPageSetup == posEndEps && line == "%%EndPageSetup") {
                posEndPageSetup = startPos;
            } else if (posPageTrailer == posEndEps && line == "%%PageTrailer") {
                posPageTrailer = startPos;
            } else if (posBeginPhotoshop == posEndEps && startsWith(line, "%BeginPhotoshop:")) {
                posBeginPhotoshop = pos;
            } else if (posBeginPhotoshop != posEndEps && posEndPhotoshop == posEndEps && line == "%EndPhotoshop") {
                posEndPhotoshop = startPos;
            } else if (inRemovableEmbedding && line == removableEmbeddingEndLine) {
                inRemovableEmbedding = false;
                removableEmbeddings.back().second = pos;
            } else if (line == "%%EOF") {
                posEof = startPos;
            } else {
                #ifdef DEBUG
                significantLine = false;
                #endif
            }
            #ifdef DEBUG
            if (significantLine) {
                EXV_DEBUG << "readWriteEpsMetadata: Found significant line \"" << line << "\" at position: " << startPos << "\n";
            }
            #endif
        }

        // check for unfinished nested documents
        if (depth != 0) {
            #ifndef SUPPRESS_WARNINGS
            EXV_WARNING << "Unmatched BeginDocument (" << depth << "x)\n";
            #endif
            throw Error(write ? 21 : 14);
        }

        // look for the unmarked trailers of some removable XMP embeddings
        size_t posXmpTrailerEnd = posEof;
        for (size_t i = 0; i < removableEmbeddingsWithUnmarkedTrailer; i++) {
            std::string line1;
            const size_t posLine1 = readPrevLine(line1, data, posXmpTrailerEnd, posEndEps);
            std::string line2;
            const size_t posLine2 = readPrevLine(line2, data, posLine1, posEndEps);
            size_t posXmpTrailer;
            if (line1 == "[/EMC pdfmark") { // Exiftool style
                posXmpTrailer = posLine1;
            } else if (line1 == "[/NamespacePop pdfmark" &&
                       line2 == "[{nextImage} 1 dict begin /Metadata {photoshop_metadata_stream} def currentdict end /PUT pdfmark") { // Photoshop style
                posXmpTrailer = posLine2;
            } else {
                #ifndef SUPPRESS_WARNINGS
                EXV_WARNING << "Unable to find XMP embedding trailer ending at position: " << posXmpTrailerEnd << "\n";
                #endif
                if (write) throw Error(21);
                break;
            }
            removableEmbeddings.push_back(std::make_pair(posXmpTrailer, posXmpTrailerEnd));
            #ifdef DEBUG
            EXV_DEBUG << "readWriteEpsMetadata: Recognized unmarked trailer of removable XMP embedding at "
                         "[" << removableEmbeddings.back().first << "," << removableEmbeddings.back().second << ")"
                         "\n";
            #endif
            posXmpTrailerEnd = posXmpTrailer;
        }

        // interpret comment "%ADO_ContainsXMP:"
        std::string line;
        readLine(line, data, posContainsXmp, posEndEps);
        bool containsXmp;
        if (line == "%ADO_ContainsXMP: MainFirst" || line == "%ADO_ContainsXMP:MainFirst") {
            containsXmp = true;
        } else if (line == "" || line == "%ADO_ContainsXMP: NoMain" || line == "%ADO_ContainsXMP:NoMain") {
            containsXmp = false;
        } else {
            #ifndef SUPPRESS_WARNINGS
            EXV_WARNING << "Invalid line \"" << line << "\" at position: " << posContainsXmp << "\n";
            #endif
            throw Error(write ? 21 : 14);
        }

        const bool deleteXmp = (write && xmpPacket.size() == 0);
        bool fixBeginXmlPacket = false;
        bool useFlexibleEmbedding = false;
        size_t xmpPos = posEndEps;
        size_t xmpSize = 0;
        if (containsXmp) {
            // search for XMP metadata
            findXmp(xmpPos, xmpSize, data, posEps, posEndEps, write);
            if (xmpPos == posEndEps) {
                #ifndef SUPPRESS_WARNINGS
                EXV_WARNING << "Unable to find XMP metadata as announced at position: " << posContainsXmp << "\n";
                #endif
            }
            // check embedding of XMP metadata
            const size_t posLineAfterXmp = readLine(line, data, xmpPos + xmpSize, posEndEps);
            if (line != "") {
                #ifndef SUPPRESS_WARNINGS
                EXV_WARNING << "Unexpected " << line.size() << " bytes of data after XMP at position: " << (xmpPos + xmpSize) << "\n";
                #endif
            } else if (!deleteXmp) {
                readLine(line, data, posLineAfterXmp, posEndEps);
                if (line == "% &&end XMP packet marker&&" || line == "%  &&end XMP packet marker&&") {
                    useFlexibleEmbedding = true;
                }
            }
        }
        if (useFlexibleEmbedding) {
            #ifdef DEBUG
            EXV_DEBUG << "readWriteEpsMetadata: Using flexible XMP embedding\n";
            #endif
            const size_t posBeginXmlPacket = readPrevLine(line, data, xmpPos, posEndEps);
            if (startsWith(line, "%begin_xml_packet:")) {
                #ifdef DEBUG
                EXV_DEBUG << "readWriteEpsMetadata: XMP embedding contains %begin_xml_packet\n";
                #endif
                if (write) {
                    fixBeginXmlPacket = true;
                    xmpSize += (xmpPos - posBeginXmlPacket);
                    xmpPos = posBeginXmlPacket;
                }
            } else if (posBeginPhotoshop != posEndEps) {
                #ifndef SUPPRESS_WARNINGS
                EXV_WARNING << "Missing %begin_xml_packet in Photoshop EPS at position: " << xmpPos << "\n";
                #endif
                if (write) throw Error(21);
            }
        }
        if (!useFlexibleEmbedding) {
            // check if there are irremovable XMP metadata blocks before EndPageSetup
            size_t posOtherXmp = containsXmp ? xmpPos : posEps;
            size_t sizeOtherXmp = 0;
            for (;;) {
                findXmp(posOtherXmp, sizeOtherXmp, data, posOtherXmp + sizeOtherXmp, posEndPageSetup, write);
                if (posOtherXmp >= posEndPageSetup) break;
                bool isRemovableEmbedding = false;
                for (std::vector<std::pair<size_t, size_t> >::const_iterator e = removableEmbeddings.begin(); e != removableEmbeddings.end(); e++) {
                    if (e->first <= posOtherXmp && posOtherXmp < e->second) {
                        isRemovableEmbedding = true;
                        break;
                    }
                }
                if (!isRemovableEmbedding) {
                    #ifndef SUPPRESS_WARNINGS
                    EXV_WARNING << "XMP metadata block is not removable at position: " << posOtherXmp << "\n";
                    #endif
                    if (write) throw Error(21);
                    break;
                }
            }
        }

        if (!write) {
            // copy XMP metadata
            xmpPacket.assign(reinterpret_cast<const char*>(data + xmpPos), xmpSize);

            // native previews
            nativePreviews.clear();
            if (posAi7ThumbnailEndData != posEndEps) {
                NativePreview nativePreview;
                std::string dummy;
                std::string lineAi7Thumbnail;
                const size_t posBeginData = readLine(lineAi7Thumbnail, data, posAi7Thumbnail, posEndEps);
                std::istringstream lineStreamAi7Thumbnail(lineAi7Thumbnail);
                lineStreamAi7Thumbnail >> dummy;
                lineStreamAi7Thumbnail >> nativePreview.width_;
                lineStreamAi7Thumbnail >> nativePreview.height_;
                std::string depth;
                lineStreamAi7Thumbnail >> depth;
                std::string lineBeginData;
                const size_t posAfterBeginData = readLine(lineBeginData, data, posBeginData, posEndEps);
                std::istringstream lineStreamBeginData(lineBeginData);
                std::string beginData;
                lineStreamBeginData >> beginData;
                lineStreamBeginData >> dummy;
                std::string type;
                lineStreamBeginData >> type;
                nativePreview.position_ = static_cast<long>(posAfterBeginData);
                nativePreview.size_ = static_cast<uint32_t>(posAi7ThumbnailEndData - posAfterBeginData);
                nativePreview.filter_ = "hex-ai7thumbnail-pnm";
                nativePreview.mimeType_ = "image/x-portable-anymap";
                if (depth != "8") {
                    #ifndef SUPPRESS_WARNINGS
                    EXV_WARNING << "Unable to handle Illustrator thumbnail depth: " << depth << "\n";
                    #endif
                } else if (beginData != "%%BeginData:") {
                    #ifndef SUPPRESS_WARNINGS
                    EXV_WARNING << "Unable to handle Illustrator thumbnail data section: " << lineBeginData << "\n";
                    #endif
                } else if (type != "Hex") {
                    #ifndef SUPPRESS_WARNINGS
                    EXV_WARNING << "Unable to handle Illustrator thumbnail data type: " << type << "\n";
                    #endif
                } else {
                    nativePreviews.push_back(nativePreview);
                }
            }
            if (posEndPhotoshop != posEndEps) {
                NativePreview nativePreview;
                nativePreview.position_ = static_cast<long>(posBeginPhotoshop);
                nativePreview.size_ = static_cast<uint32_t>(posEndPhotoshop - posBeginPhotoshop);
                nativePreview.width_ = 0;
                nativePreview.height_ = 0;
                nativePreview.filter_ = "hex-irb";
                nativePreview.mimeType_ = "image/jpeg";
                nativePreviews.push_back(nativePreview);
            }
            if (sizeWmf != 0) {
                NativePreview nativePreview;
                nativePreview.position_ = static_cast<long>(posWmf);
                nativePreview.size_ = sizeWmf;
                nativePreview.width_ = 0;
                nativePreview.height_ = 0;
                nativePreview.filter_ = "";
                nativePreview.mimeType_ = "image/x-wmf";
                nativePreviews.push_back(nativePreview);
            }
            if (sizeTiff != 0) {
                NativePreview nativePreview;
                nativePreview.position_ = static_cast<long>(posTiff);
                nativePreview.size_ = sizeTiff;
                nativePreview.width_ = 0;
                nativePreview.height_ = 0;
                nativePreview.filter_ = "";
                nativePreview.mimeType_ = "image/tiff";
                nativePreviews.push_back(nativePreview);
            }
        } else {
            // check for Adobe Illustrator 8.0 or older
            if (illustrator8) {
                #ifndef SUPPRESS_WARNINGS
                EXV_WARNING << "Unable to write to EPS files created by Adobe Illustrator 8.0 or older.\n";
                #endif
                throw Error(21);
            }

            // create temporary output file
            BasicIo::AutoPtr tempIo(io.temporary());
            assert (tempIo.get() != 0);
            if (!tempIo->isopen()) {
                #ifndef SUPPRESS_WARNINGS
                EXV_WARNING << "Unable to create temporary file for writing.\n";
                #endif
                throw Error(21);
            }
            #ifdef DEBUG
            EXV_DEBUG << "readWriteEpsMetadata: Created temporary file " << tempIo->path() << "\n";
            #endif

            // sort all positions
            std::vector<size_t> positions;
            positions.push_back(posLanguageLevel);
            positions.push_back(posContainsXmp);
            positions.push_back(posPages);
            positions.push_back(posExiv2Version);
            positions.push_back(posExiv2Website);
            positions.push_back(posEndComments);
            positions.push_back(posPage);
            positions.push_back(posBeginPageSetup);
            positions.push_back(posEndPageSetup);
            positions.push_back(posPageTrailer);
            positions.push_back(posEof);
            positions.push_back(posEndEps);
            if (useFlexibleEmbedding) {
                positions.push_back(xmpPos);
            }
            for (std::vector<std::pair<size_t, size_t> >::const_iterator e = removableEmbeddings.begin(); e != removableEmbeddings.end(); e++) {
                positions.push_back(e->first);
            }
            std::sort(positions.begin(), positions.end());

            // assemble result EPS document
            if (dosEps) {
                // DOS EPS header will be written afterwards
                writeTemp(*tempIo, std::string(30, '\x00'));
            }
            const std::string containsXmpLine = deleteXmp ? "%ADO_ContainsXMP: NoMain" : "%ADO_ContainsXMP: MainFirst";
            const uint32_t posEpsNew = posTemp(*tempIo);
            size_t prevPos = posEps;
            size_t prevSkipPos = prevPos;
            for (std::vector<size_t>::const_iterator i = positions.begin(); i != positions.end(); i++) {
                const size_t pos = *i;
                if (pos == prevPos) continue;
                #ifdef DEBUG
                EXV_DEBUG << "readWriteEpsMetadata: Writing at " << pos << "\n";
                #endif
                if (pos < prevSkipPos) {
                    #ifndef SUPPRESS_WARNINGS
                    EXV_WARNING << "Internal error while assembling the result EPS document: "
                                   "Unable to continue at position " << pos << " after skipping to position " << prevSkipPos << "\n";
                    #endif
                    throw Error(21);
                }
                writeTemp(*tempIo, data + prevSkipPos, pos - prevSkipPos);
                const size_t posLineEnd = readLine(line, data, pos, posEndEps);
                size_t skipPos = pos;
                // add last line ending if necessary
                if (pos == posEndEps && pos >= 1 && data[pos - 1] != '\r' && data[pos - 1] != '\n') {
                    writeTemp(*tempIo, lineEnding);
                    #ifdef DEBUG
                    EXV_DEBUG << "readWriteEpsMetadata: Added missing line ending of last line\n";
                    #endif
                }
                // update and complement DSC comments
                if (pos == posLanguageLevel && posLanguageLevel != posEndEps && !deleteXmp && !useFlexibleEmbedding) {
                    if (line == "%%LanguageLevel:1" || line == "%%LanguageLevel: 1") {
                        writeTemp(*tempIo, "%%LanguageLevel: 2" + lineEnding);
                        skipPos = posLineEnd;
                        #ifdef DEBUG
                        EXV_DEBUG << "readWriteEpsMetadata: Skipping to " << skipPos << " at " << __FILE__ << ":" << __LINE__ << "\n";
                        #endif
                    }
                }
                if (pos == posContainsXmp && posContainsXmp != posEndEps) {
                    if (line != containsXmpLine) {
                        writeTemp(*tempIo, containsXmpLine + lineEnding);
                        skipPos = posLineEnd;
                        #ifdef DEBUG
                        EXV_DEBUG << "readWriteEpsMetadata: Skipping to " << skipPos << " at " << __FILE__ << ":" << __LINE__ << "\n";
                        #endif
                    }
                }
                if (pos == posExiv2Version && posExiv2Version != posEndEps) {
                    writeTemp(*tempIo, "%Exiv2Version: " + versionNumberHexString() + lineEnding);
                    skipPos = posLineEnd;
                    #ifdef DEBUG
                    EXV_DEBUG << "readWriteEpsMetadata: Skipping to " << skipPos << " at " << __FILE__ << ":" << __LINE__ << "\n";
                    #endif
                }
                if (pos == posExiv2Website && posExiv2Website != posEndEps) {
                    writeTemp(*tempIo, "%Exiv2Website: http://www.exiv2.org/" + lineEnding);
                    skipPos = posLineEnd;
                    #ifdef DEBUG
                    EXV_DEBUG << "readWriteEpsMetadata: Skipping to " << skipPos << " at " << __FILE__ << ":" << __LINE__ << "\n";
                    #endif
                }
                if (pos == posEndComments) {
                    if (posLanguageLevel == posEndEps && !deleteXmp && !useFlexibleEmbedding) {
                        writeTemp(*tempIo, "%%LanguageLevel: 2" + lineEnding);
                    }
                    if (posContainsXmp == posEndEps) {
                        writeTemp(*tempIo, containsXmpLine + lineEnding);
                    }
                    if (posPages == posEndEps) {
                        writeTemp(*tempIo, "%%Pages: 1" + lineEnding);
                    }
                    if (posExiv2Version == posEndEps) {
                        writeTemp(*tempIo, "%Exiv2Version: " + versionNumberHexString() + lineEnding);
                    }
                    if (posExiv2Website == posEndEps) {
                        writeTemp(*tempIo, "%Exiv2Website: http://www.exiv2.org/" + lineEnding);
                    }
                    readLine(line, data, posEndComments, posEndEps);
                    if (line != "%%EndComments") {
                        writeTemp(*tempIo, "%%EndComments" + lineEnding);
                    }
                }
                if (pos == posPage) {
                    if (!startsWith(line, "%%Page:")) {
                        writeTemp(*tempIo, "%%Page: 1 1" + lineEnding);
                        writeTemp(*tempIo, "%%EndPageComments" + lineEnding);
                    }
                }
                if (pos == posBeginPageSetup) {
                    if (line != "%%BeginPageSetup") {
                        writeTemp(*tempIo, "%%BeginPageSetup" + lineEnding);
                    }
                }
                if (useFlexibleEmbedding) {
                    // insert XMP metadata into existing flexible embedding
                    if (pos == xmpPos) {
                        if (fixBeginXmlPacket) {
                            writeTemp(*tempIo, "%begin_xml_packet: " + toString(xmpPacket.size()) + lineEnding);
                        }
                        writeTemp(*tempIo, xmpPacket);
                        skipPos += xmpSize;
                        #ifdef DEBUG
                        EXV_DEBUG << "readWriteEpsMetadata: Skipping to " << skipPos << " at " << __FILE__ << ":" << __LINE__ << "\n";
                        #endif
                    }
                }
                if (!useFlexibleEmbedding) {
                    // remove preceding embedding(s)
                    for (std::vector<std::pair<size_t, size_t> >::const_iterator e = removableEmbeddings.begin(); e != removableEmbeddings.end(); e++) {
                        if (pos == e->first) {
                            skipPos = e->second;
                            #ifdef DEBUG
                            EXV_DEBUG << "readWriteEpsMetadata: Skipping to " << skipPos << " at " << __FILE__ << ":" << __LINE__ << "\n";
                            #endif
                            break;
                        }
                    }
                    // insert XMP metadata with new flexible embedding, if necessary
                    if (pos == posEndPageSetup && !deleteXmp) {
                        writeTemp(*tempIo, "%Exiv2BeginXMP: Before %%EndPageSetup" + lineEnding);
                        if (corelDraw) {
                            writeTemp(*tempIo, "%Exiv2Notice: The following line is needed by CorelDRAW." + lineEnding);
                            writeTemp(*tempIo, "@rs" + lineEnding);
                        }
                        if (posBeginPhotoshop != posEndEps) {
                            writeTemp(*tempIo, "%Exiv2Notice: The following line is needed by Photoshop." + lineEnding);
                            writeTemp(*tempIo, "%begin_xml_code" + lineEnding);
                        }
                        writeTemp(*tempIo, "/currentdistillerparams where" + lineEnding);
                        writeTemp(*tempIo, "{pop currentdistillerparams /CoreDistVersion get 5000 lt} {true} ifelse" + lineEnding);
                        writeTemp(*tempIo, "{userdict /Exiv2_pdfmark /cleartomark load put" + lineEnding);
                        writeTemp(*tempIo, "    userdict /Exiv2_metafile_pdfmark {flushfile cleartomark} bind put}" + lineEnding);
                        writeTemp(*tempIo, "{userdict /Exiv2_pdfmark /pdfmark load put" + lineEnding);
                        writeTemp(*tempIo, "    userdict /Exiv2_metafile_pdfmark {/PUT pdfmark} bind put} ifelse" + lineEnding);
                        writeTemp(*tempIo, "[/NamespacePush Exiv2_pdfmark" + lineEnding);
                        writeTemp(*tempIo, "[/_objdef {Exiv2_metadata_stream} /type /stream /OBJ Exiv2_pdfmark" + lineEnding);
                        writeTemp(*tempIo, "[{Exiv2_metadata_stream} 2 dict begin" + lineEnding);
                        writeTemp(*tempIo, "    /Type /Metadata def /Subtype /XML def currentdict end /PUT Exiv2_pdfmark" + lineEnding);
                        writeTemp(*tempIo, "[{Exiv2_metadata_stream}" + lineEnding);
                        writeTemp(*tempIo, "    currentfile 0 (% &&end XMP packet marker&&)" + lineEnding);
                        writeTemp(*tempIo, "    /SubFileDecode filter Exiv2_metafile_pdfmark" + lineEnding);
                        if (posBeginPhotoshop != posEndEps) {
                            writeTemp(*tempIo, "%Exiv2Notice: The following line is needed by Photoshop. "
                                               "Parameter must be exact size of XMP metadata." + lineEnding);
                            writeTemp(*tempIo, "%begin_xml_packet: " + toString(xmpPacket.size()) + lineEnding);
                        }
                        writeTemp(*tempIo, xmpPacket);
                        writeTemp(*tempIo, lineEnding);
                        writeTemp(*tempIo, "% &&end XMP packet marker&&" + lineEnding);
                        writeTemp(*tempIo, "[/Document 1 dict begin" + lineEnding);
                        writeTemp(*tempIo, "    /Metadata {Exiv2_metadata_stream} def currentdict end /BDC Exiv2_pdfmark" + lineEnding);
                        if (posBeginPhotoshop != posEndEps) {
                            writeTemp(*tempIo, "%Exiv2Notice: The following line is needed by Photoshop." + lineEnding);
                            writeTemp(*tempIo, "%end_xml_code" + lineEnding);
                        }
                        if (corelDraw) {
                            writeTemp(*tempIo, "%Exiv2Notice: The following line is needed by CorelDRAW." + lineEnding);
                            writeTemp(*tempIo, "@sv" + lineEnding);
                        }
                        writeTemp(*tempIo, "%Exiv2EndXMP" + lineEnding);
                    }
                }
                if (pos == posEndPageSetup) {
                    if (line != "%%EndPageSetup") {
                        writeTemp(*tempIo, "%%EndPageSetup" + lineEnding);
                    }
                }
                if (!useFlexibleEmbedding) {
                    if (pos == posPageTrailer && !deleteXmp) {
                        if (!implicitPageTrailer) {
                            skipPos = posLineEnd;
                            #ifdef DEBUG
                            EXV_DEBUG << "readWriteEpsMetadata: Skipping to " << skipPos << " at " << __FILE__ << ":" << __LINE__ << "\n";
                            #endif
                        }
                        writeTemp(*tempIo, "%%PageTrailer" + lineEnding);
                        writeTemp(*tempIo, "%Exiv2BeginXMP: After %%PageTrailer" + lineEnding);
                        writeTemp(*tempIo, "[/EMC Exiv2_pdfmark" + lineEnding);
                        writeTemp(*tempIo, "[/NamespacePop Exiv2_pdfmark" + lineEnding);
                        writeTemp(*tempIo, "%Exiv2EndXMP" + lineEnding);
                    }
                }
                // add EOF comment if necessary
                if (pos == posEndEps && posEof == posEndEps) {
                    writeTemp(*tempIo, "%%EOF" + lineEnding);
                }
                prevPos = pos;
                prevSkipPos = skipPos;
            }
            const uint32_t posEndEpsNew = posTemp(*tempIo);
            #ifdef DEBUG
            EXV_DEBUG << "readWriteEpsMetadata: New EPS size: " << (posEndEpsNew - posEpsNew) << "\n";
            #endif
            if (dosEps) {
                // write WMF and/or TIFF section if present
                writeTemp(*tempIo, data + posWmf, sizeWmf);
                writeTemp(*tempIo, data + posTiff, sizeTiff);
                #ifdef DEBUG
                EXV_DEBUG << "readWriteEpsMetadata: New DOS EPS total size: " << posTemp(*tempIo) << "\n";
                #endif
                // write DOS EPS header
                if (tempIo->seek(0, BasicIo::beg) != 0) {
                    #ifndef SUPPRESS_WARNINGS
                    EXV_WARNING << "Internal error while seeking in temporary file.\n";
                    #endif
                    throw Error(21);
                }
                byte dosEpsHeader[30];
                dosEpsSignature.copy(reinterpret_cast<char*>(dosEpsHeader), dosEpsSignature.size());
                ul2Data(dosEpsHeader +  4, posEpsNew,                                  littleEndian);
                ul2Data(dosEpsHeader +  8, posEndEpsNew - posEpsNew,                   littleEndian);
                ul2Data(dosEpsHeader + 12, sizeWmf == 0 ? 0 : posEndEpsNew,            littleEndian);
                ul2Data(dosEpsHeader + 16, sizeWmf,                                    littleEndian);
                ul2Data(dosEpsHeader + 20, sizeTiff == 0 ? 0 : posEndEpsNew + sizeWmf, littleEndian);
                ul2Data(dosEpsHeader + 24, sizeTiff,                                   littleEndian);
                us2Data(dosEpsHeader + 28, 0xFFFF,                                     littleEndian);
                writeTemp(*tempIo, dosEpsHeader, sizeof(dosEpsHeader));
            }

            // copy temporary file to real output file
            io.close();
            io.transfer(*tempIo);
        }
    }

} // namespace

// *****************************************************************************
// class member definitions
namespace Exiv2
{

    EpsImage::EpsImage(BasicIo::AutoPtr io, bool create)
            : Image(ImageType::eps, mdXmp, io)
    {
        //LogMsg::setLevel(LogMsg::debug);
        if (create) {
            if (io_->open() == 0) {
                #ifdef DEBUG
                EXV_DEBUG << "Exiv2::EpsImage:: Creating blank EPS image\n";
                #endif
                IoCloser closer(*io_);
                if (io_->write(reinterpret_cast<const byte*>(epsBlank.data()), static_cast<long>(epsBlank.size())) != static_cast<long>(epsBlank.size())) {
                    #ifndef SUPPRESS_WARNINGS
                    EXV_WARNING << "Failed to write blank EPS image.\n";
                    #endif
                    throw Error(21);
                }
            }
        }
    }

    std::string EpsImage::mimeType() const
    {
        return "application/postscript";
    }

    void EpsImage::setComment(const std::string& /*comment*/)
    {
        throw Error(32, "Image comment", "EPS");
    }

    void EpsImage::readMetadata()
    {
        #ifdef DEBUG
        EXV_DEBUG << "Exiv2::EpsImage::readMetadata: Reading EPS file " << io_->path() << "\n";
        #endif

        // read metadata
        readWriteEpsMetadata(*io_, xmpPacket_, nativePreviews_, /* write = */ false);

        // decode XMP metadata
        if (xmpPacket_.size() > 0 && XmpParser::decode(xmpData_, xmpPacket_) > 1) {
            #ifndef SUPPRESS_WARNINGS
            EXV_WARNING << "Failed to decode XMP metadata.\n";
            #endif
            throw Error(14);
        }

        #ifdef DEBUG
        EXV_DEBUG << "Exiv2::EpsImage::readMetadata: Finished reading EPS file " << io_->path() << "\n";
        #endif
    }

    void EpsImage::writeMetadata()
    {
        #ifdef DEBUG
        EXV_DEBUG << "Exiv2::EpsImage::writeMetadata: Writing EPS file " << io_->path() << "\n";
        #endif

        // encode XMP metadata if necessary
        if (!writeXmpFromPacket() && XmpParser::encode(xmpPacket_, xmpData_) > 1) {
            #ifndef SUPPRESS_WARNINGS
            EXV_WARNING << "Failed to encode XMP metadata.\n";
            #endif
            throw Error(21);
        }

        // write metadata
        readWriteEpsMetadata(*io_, xmpPacket_, nativePreviews_, /* write = */ true);

        #ifdef DEBUG
        EXV_DEBUG << "Exiv2::EpsImage::writeMetadata: Finished writing EPS file " << io_->path() << "\n";
        #endif
    }

    // *************************************************************************
    // free functions
    Image::AutoPtr newEpsInstance(BasicIo::AutoPtr io, bool create)
    {
        Image::AutoPtr image(new EpsImage(io, create));
        if (!image->good()) {
            image.reset();
        }
        return image;
    }

    bool isEpsType(BasicIo& iIo, bool advance)
    {
        // read as many bytes as needed for the longest (DOS) EPS signature
        long bufSize = static_cast<long>(dosEpsSignature.size());
        for (size_t i = 0; i < (sizeof epsFirstLine) / (sizeof *epsFirstLine); i++) {
            if (bufSize < static_cast<long>(epsFirstLine[i].size())) {
                bufSize = static_cast<long>(epsFirstLine[i].size());
            }
        }
        DataBuf buf = iIo.read(bufSize);
        if (iIo.error() || buf.size_ != bufSize) {
            return false;
        }
        // check for all possible (DOS) EPS signatures
        bool matched = (memcmp(buf.pData_, dosEpsSignature.data(), dosEpsSignature.size()) == 0);
        for (size_t i = 0; !matched && i < (sizeof epsFirstLine) / (sizeof *epsFirstLine); i++) {
            matched = (memcmp(buf.pData_, epsFirstLine[i].data(), epsFirstLine[i].size()) == 0);
        }
        // seek back if possible and requested
        if (!advance || !matched) {
            iIo.seek(-buf.size_, BasicIo::cur);
        }
        return matched;
    }

} // namespace Exiv2
