//    Copyright (C) 2019-2022 Jakub Melka
//
//    This file is part of PDF4QT.
//
//    PDF4QT is free software: you can redistribute it and/or modify
//    it under the terms of the GNU Lesser General Public License as published by
//    the Free Software Foundation, either version 3 of the License, or
//    with the written consent of the copyright owner, any later version.
//
//    PDF4QT 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 Lesser General Public License for more details.
//
//    You should have received a copy of the GNU Lesser General Public License
//    along with PDF4QT.  If not, see <https://www.gnu.org/licenses/>.

#include "pdfpagecontentprocessor.h"
#include "pdfdocument.h"
#include "pdfexception.h"
#include "pdfimage.h"
#include "pdfpattern.h"
#include "pdfexecutionpolicy.h"
#include "pdfstreamfilters.h"

#include <QPainterPathStroker>
#include <QtMath>

#include "pdfdbgheap.h"

namespace pdf
{

// Graphic state operators - mapping from PDF name to the enum, splitted into groups.
// Please see Table 4.1 in PDF Reference 1.7, chapter 4.1 - Graphic Objects.
//
//  General graphic state:      w, J, j, M, d, ri, i, gs
//  Special graphic state:      q, Q, cm
//  Path construction:          m, l, c, v, y, h, re
//  Path painting:              S, s, F, f, f*, B, B*, b, b*, n
//  Clipping paths:             W, W*
//  Text object:                BT, ET
//  Text state:                 Tc, Tw, Tz, TL, Tf, Tr, Ts
//  Text positioning:           Td, TD, Tm, T*
//  Text showing:               Tj, TJ, ', "
//  Type 3 font:                d0, d1
//  Color:                      CS, cs, SC, SCN, sc, scn, G, g, RG, rg, K, k
//  Shading pattern:            sh
//  Inline images:              BI, ID, EI
//  XObject:                    Do
//  Marked content:             MP, DP, BMC, BDC, EMC
//  Compatibility:              BX, EX

static constexpr const std::pair<const char*, PDFPageContentProcessor::Operator> operators[] =
{
    // General graphic state        w, J, j, M, d, ri, i, gs
    { "w", PDFPageContentProcessor::Operator::SetLineWidth },
    { "J", PDFPageContentProcessor::Operator::SetLineCap },
    { "j", PDFPageContentProcessor::Operator::SetLineJoin },
    { "M", PDFPageContentProcessor::Operator::SetMitterLimit },
    { "d", PDFPageContentProcessor::Operator::SetLineDashPattern },
    { "ri", PDFPageContentProcessor::Operator::SetRenderingIntent },
    { "i", PDFPageContentProcessor::Operator::SetFlatness },
    { "gs", PDFPageContentProcessor::Operator::SetGraphicState },

    // Special graphic state:       q, Q, cm
    { "q", PDFPageContentProcessor::Operator::SaveGraphicState },
    { "Q", PDFPageContentProcessor::Operator::RestoreGraphicState },
    { "cm", PDFPageContentProcessor::Operator::AdjustCurrentTransformationMatrix },

    // Path construction:           m, l, c, v, y, h, re
    { "m", PDFPageContentProcessor::Operator::MoveCurrentPoint },
    { "l", PDFPageContentProcessor::Operator::LineTo },
    { "c", PDFPageContentProcessor::Operator::Bezier123To },
    { "v", PDFPageContentProcessor::Operator::Bezier23To },
    { "y", PDFPageContentProcessor::Operator::Bezier13To },
    { "h", PDFPageContentProcessor::Operator::EndSubpath },
    { "re", PDFPageContentProcessor::Operator::Rectangle },

    // Path painting:               S, s, f, F, f*, B, B*, b, b*, n
    { "S", PDFPageContentProcessor::Operator::PathStroke },
    { "s", PDFPageContentProcessor::Operator::PathCloseStroke },
    { "f", PDFPageContentProcessor::Operator::PathFillWinding },
    { "F", PDFPageContentProcessor::Operator::PathFillWinding2 },
    { "f*", PDFPageContentProcessor::Operator::PathFillEvenOdd },
    { "B", PDFPageContentProcessor::Operator::PathFillStrokeWinding },
    { "B*", PDFPageContentProcessor::Operator::PathFillStrokeEvenOdd },
    { "b", PDFPageContentProcessor::Operator::PathCloseFillStrokeWinding },
    { "b*", PDFPageContentProcessor::Operator::PathCloseFillStrokeEvenOdd },
    { "n", PDFPageContentProcessor::Operator::PathClear },

    // Clipping paths:             W, W*
    { "W", PDFPageContentProcessor::Operator::ClipWinding },
    { "W*", PDFPageContentProcessor::Operator::ClipEvenOdd },

    // Text object:                BT, ET
    { "BT", PDFPageContentProcessor::Operator::TextBegin },
    { "ET", PDFPageContentProcessor::Operator::TextEnd },

    // Text state:                 Tc, Tw, Tz, TL, Tf, Tr, Ts
    { "Tc", PDFPageContentProcessor::Operator::TextSetCharacterSpacing },
    { "Tw", PDFPageContentProcessor::Operator::TextSetWordSpacing },
    { "Tz", PDFPageContentProcessor::Operator::TextSetHorizontalScale },
    { "TL", PDFPageContentProcessor::Operator::TextSetLeading },
    { "Tf", PDFPageContentProcessor::Operator::TextSetFontAndFontSize },
    { "Tr", PDFPageContentProcessor::Operator::TextSetRenderMode },
    { "Ts", PDFPageContentProcessor::Operator::TextSetRise },

    // Text positioning:           Td, TD, Tm, T*
    { "Td", PDFPageContentProcessor::Operator::TextMoveByOffset },
    { "TD", PDFPageContentProcessor::Operator::TextSetLeadingAndMoveByOffset },
    { "Tm", PDFPageContentProcessor::Operator::TextSetMatrix },
    { "T*", PDFPageContentProcessor::Operator::TextMoveByLeading },

    // Text showing:               Tj, TJ, ', "
    { "Tj", PDFPageContentProcessor::Operator::TextShowTextString },
    { "TJ", PDFPageContentProcessor::Operator::TextShowTextIndividualSpacing },
    { "'", PDFPageContentProcessor::Operator::TextNextLineShowText },
    { "\"", PDFPageContentProcessor::Operator::TextSetSpacingAndShowText },

    // Type 3 font:                d0, d1
    { "d0", PDFPageContentProcessor::Operator::Type3FontSetOffset },
    { "d1", PDFPageContentProcessor::Operator::Type3FontSetOffsetAndBB },

    // Color:                      CS, cs, SC, SCN, sc, scn, G, g, RG, rg, K, k
    { "CS", PDFPageContentProcessor::Operator::ColorSetStrokingColorSpace },
    { "cs", PDFPageContentProcessor::Operator::ColorSetFillingColorSpace },
    { "SC", PDFPageContentProcessor::Operator::ColorSetStrokingColor },
    { "SCN", PDFPageContentProcessor::Operator::ColorSetStrokingColorN },
    { "sc", PDFPageContentProcessor::Operator::ColorSetFillingColor },
    { "scn", PDFPageContentProcessor::Operator::ColorSetFillingColorN },
    { "G", PDFPageContentProcessor::Operator::ColorSetDeviceGrayStroking },
    { "g", PDFPageContentProcessor::Operator::ColorSetDeviceGrayFilling },
    { "RG", PDFPageContentProcessor::Operator::ColorSetDeviceRGBStroking },
    { "rg", PDFPageContentProcessor::Operator::ColorSetDeviceRGBFilling },
    { "K", PDFPageContentProcessor::Operator::ColorSetDeviceCMYKStroking },
    { "k", PDFPageContentProcessor::Operator::ColorSetDeviceCMYKFilling },

    // Shading pattern:            sh
    { "sh", PDFPageContentProcessor::Operator::ShadingPaintShape },

    // Inline images:              BI, ID, EI
    { "BI", PDFPageContentProcessor::Operator::InlineImageBegin },
    { "ID", PDFPageContentProcessor::Operator::InlineImageData },
    { "EI", PDFPageContentProcessor::Operator::InlineImageEnd },

    // XObject:                    Do
    { "Do", PDFPageContentProcessor::Operator::PaintXObject },

    // Marked content:             MP, DP, BMC, BDC, EMC
    { "MP", PDFPageContentProcessor::Operator::MarkedContentPoint },
    { "DP", PDFPageContentProcessor::Operator::MarkedContentPointWithProperties },
    { "BMC", PDFPageContentProcessor::Operator::MarkedContentBegin },
    { "BDC", PDFPageContentProcessor::Operator::MarkedContentBeginWithProperties },
    { "EMC", PDFPageContentProcessor::Operator::MarkedContentEnd },

    // Compatibility:              BX, EX
    { "BX", PDFPageContentProcessor::Operator::CompatibilityBegin },
    { "EX", PDFPageContentProcessor::Operator::CompatibilityEnd }
};

void PDFPageContentProcessor::initDictionaries(const PDFObject& resourcesObject)
{
    const PDFObject& resources = m_document->getObject(resourcesObject);
    auto getDictionary = [this, &resources](const char* resourceName) -> const pdf::PDFDictionary*
    {
        if (resources.isDictionary() && resources.getDictionary()->hasKey(resourceName))
        {
            const PDFObject& resourceDictionary = m_document->getObject(resources.getDictionary()->get(resourceName));
            if (resourceDictionary.isDictionary())
            {
                return resourceDictionary.getDictionary();
            }
        }

        return nullptr;
    };

    m_colorSpaceDictionary = getDictionary(COLOR_SPACE_DICTIONARY);
    m_fontDictionary = getDictionary("Font");
    m_xobjectDictionary = getDictionary("XObject");
    m_extendedGraphicStateDictionary = getDictionary(PDF_RESOURCE_EXTGSTATE);
    m_propertiesDictionary = getDictionary("Properties");
    m_shadingDictionary = getDictionary("Shading");
    m_patternDictionary = getDictionary("Pattern");
    m_procedureSets = NoProcSet;

    if (resources.isDictionary() && resources.getDictionary()->hasKey("ProcSet"))
    {
        PDFDocumentDataLoaderDecorator loader(m_document);
        std::vector<QByteArray> procedureSetNames = loader.readNameArrayFromDictionary(resources.getDictionary(), "ProcSet");

        ProcedureSets newProcSet = EmptyProcSet;
        for (const QByteArray& procedureSetName : procedureSetNames)
        {
           if (procedureSetName == "PDF")
           {
               newProcSet.setFlag(PDF);
           }
           else if (procedureSetName == "Text")
           {
               newProcSet.setFlag(Text);
           }
           else if (procedureSetName == "ImageB")
           {
               newProcSet.setFlag(ImageB);
           }
           else if (procedureSetName == "ImageC")
           {
               newProcSet.setFlag(ImageC);
           }
           else if (procedureSetName == "ImageI")
           {
               newProcSet.setFlag(ImageI);
           }
        }

        if (newProcSet)
        {
            m_procedureSets = newProcSet;
        }
    }
}

PDFPageContentProcessor::PDFPageContentProcessor(const PDFPage* page,
                                                 const PDFDocument* document,
                                                 const PDFFontCache* fontCache,
                                                 const PDFCMS* CMS,
                                                 const PDFOptionalContentActivity* optionalContentActivity,
                                                 QTransform pagePointToDevicePointMatrix,
                                                 const PDFMeshQualitySettings& meshQualitySettings) :
    m_page(page),
    m_document(document),
    m_fontCache(fontCache),
    m_CMS(CMS),
    m_optionalContentActivity(optionalContentActivity),
    m_operationControl(nullptr),
    m_colorSpaceDictionary(nullptr),
    m_fontDictionary(nullptr),
    m_xobjectDictionary(nullptr),
    m_extendedGraphicStateDictionary(nullptr),
    m_propertiesDictionary(nullptr),
    m_shadingDictionary(nullptr),
    m_patternDictionary(nullptr),
    m_procedureSets(NoProcSet),
    m_textBeginEndState(0),
    m_compatibilityBeginEndState(0),
    m_drawingUncoloredTilingPatternState(0),
    m_patternBaseMatrix(pagePointToDevicePointMatrix),
    m_pagePointToDevicePointMatrix(pagePointToDevicePointMatrix),
    m_meshQualitySettings(meshQualitySettings),
    m_structuralParentKey(0)
{
    Q_ASSERT(page);
    Q_ASSERT(document);

    m_structuralParentKey = page->getStructureParentKey();

    PDFExecutionPolicy::startProcessingContentStream();

    QPainterPath pageRectPath;
    pageRectPath.addRect(m_page->getMediaBox());
    m_pageBoundingRectDeviceSpace = pagePointToDevicePointMatrix.map(pageRectPath).boundingRect();

    initDictionaries(m_page->getResources());
}

PDFPageContentProcessor::~PDFPageContentProcessor()
{
    PDFExecutionPolicy::endProcessingContentStream();
}

void PDFPageContentProcessor::initializeProcessor()
{
    // Clear the old errors
    m_errorList.clear();

    // Initialize default color spaces (gray, RGB, CMYK)
    try
    {
        m_deviceGrayColorSpace = PDFAbstractColorSpace::createDeviceColorSpaceByName(m_colorSpaceDictionary, m_document, COLOR_SPACE_NAME_DEVICE_GRAY);
        m_deviceRGBColorSpace = PDFAbstractColorSpace::createDeviceColorSpaceByName(m_colorSpaceDictionary, m_document, COLOR_SPACE_NAME_DEVICE_RGB);
        m_deviceCMYKColorSpace = PDFAbstractColorSpace::createDeviceColorSpaceByName(m_colorSpaceDictionary, m_document, COLOR_SPACE_NAME_DEVICE_CMYK);
    }
    catch (const PDFException& exception)
    {
        m_errorList.append(PDFRenderError(RenderErrorType::Error, exception.getMessage()));

        // Create default color spaces anyway, but do not try to load them...
        m_deviceGrayColorSpace.reset(new PDFDeviceGrayColorSpace);
        m_deviceRGBColorSpace.reset(new PDFDeviceRGBColorSpace);
        m_deviceCMYKColorSpace.reset(new PDFDeviceCMYKColorSpace);
    }

    m_graphicState.setStrokeColorSpace(m_deviceGrayColorSpace);
    m_graphicState.setStrokeColor(m_deviceGrayColorSpace->getDefaultColor(m_CMS, m_graphicState.getRenderingIntent(), this), m_deviceGrayColorSpace->getDefaultColorOriginal());
    m_graphicState.setFillColorSpace(m_deviceGrayColorSpace);
    m_graphicState.setFillColor(m_deviceGrayColorSpace->getDefaultColor(m_CMS, m_graphicState.getRenderingIntent(), this), m_deviceGrayColorSpace->getDefaultColorOriginal());
    m_graphicState.setStateFlags(PDFPageContentProcessorState::StateAll);
    updateGraphicState();
}

QList<PDFRenderError> PDFPageContentProcessor::processContents()
{
    const PDFObject& contents = m_page->getContents();

    // Initialize stream processor
    initializeProcessor();

    if (contents.isArray())
    {
        const PDFArray* array = contents.getArray();
        const size_t count = array->getCount();

        for (size_t i = 0; i < count; ++i)
        {
            if (isProcessingCancelled())
            {
                // Break, if processing is being cancelled
                break;
            }

            const PDFObject& streamObject = m_document->getObject(array->getItem(i));
            if (streamObject.isStream())
            {
                processContentStream(streamObject.getStream());
            }
            else
            {
                m_errorList.append(PDFRenderError(RenderErrorType::Error, PDFTranslationContext::tr("Invalid page contents.")));
            }
        }
    }
    else if (contents.isStream())
    {
        processContentStream(contents.getStream());
    }
    else
    {
        m_errorList.append(PDFRenderError(RenderErrorType::Error, PDFTranslationContext::tr("Invalid page contents.")));
    }

    if (!m_stack.empty())
    {
        // Stack is not empty. There was more saves than restores. This is error.
        m_errorList.append(PDFRenderError(RenderErrorType::Error, PDFTranslationContext::tr("Graphic state stack was saved more times, than was restored.")));

        while (!m_stack.empty())
        {
            operatorRestoreGraphicState();
        }
    }

    finishMarkedContent();
    return m_errorList;
}

void PDFPageContentProcessor::reportRenderError(RenderErrorType type, QString message)
{
    m_errorList.append(PDFRenderError(type, qMove(message)));
}

void PDFPageContentProcessor::performPathPainting(const QPainterPath& path, bool stroke, bool fill, bool text, Qt::FillRule fillRule)
{
    Q_UNUSED(path);
    Q_UNUSED(stroke);
    Q_UNUSED(fill);
    Q_UNUSED(text);
    Q_UNUSED(fillRule);
}

bool PDFPageContentProcessor::performPathPaintingUsingShading(const QPainterPath& path, bool stroke, bool fill, const PDFShadingPattern* shadingPattern)
{
    Q_UNUSED(path);
    Q_UNUSED(stroke);
    Q_UNUSED(fill);
    Q_UNUSED(shadingPattern);

    return false;
}

void PDFPageContentProcessor::performFinishPathPainting()
{

}

void PDFPageContentProcessor::performClipping(const QPainterPath& path, Qt::FillRule fillRule)
{
    Q_UNUSED(path);
    Q_UNUSED(fillRule);
}

bool PDFPageContentProcessor::performOriginalImagePainting(const PDFImage& image)
{
    Q_UNUSED(image);
    return false;
}

void PDFPageContentProcessor::performImagePainting(const QImage& image)
{
    Q_UNUSED(image);
}

void PDFPageContentProcessor::performMeshPainting(const PDFMesh& mesh)
{
    Q_UNUSED(mesh);
}

void PDFPageContentProcessor::performUpdateGraphicsState(const PDFPageContentProcessorState& state)
{
    if (state.getStateFlags().testFlag(PDFPageContentProcessorState::StateTextFont) ||
        state.getStateFlags().testFlag(PDFPageContentProcessorState::StateTextFontSize))
    {
        m_realizedFont.dirty();
    }
}

void PDFPageContentProcessor::performSaveGraphicState(ProcessOrder order)
{
    Q_UNUSED(order);
}

void PDFPageContentProcessor::performRestoreGraphicState(ProcessOrder order)
{
    Q_UNUSED(order);
}

void PDFPageContentProcessor::performMarkedContentPoint(const QByteArray& tag, const PDFObject& properties)
{
    Q_UNUSED(tag);
    Q_UNUSED(properties);
}

void PDFPageContentProcessor::performMarkedContentBegin(const QByteArray& tag, const PDFObject& properties)
{
    Q_UNUSED(tag);
    Q_UNUSED(properties);
}

void PDFPageContentProcessor::performMarkedContentEnd()
{

}

void PDFPageContentProcessor::performSetCharWidth(PDFReal wx, PDFReal wy)
{
    Q_UNUSED(wx);
    Q_UNUSED(wy);
}

void PDFPageContentProcessor::performSetCacheDevice(PDFReal wx, PDFReal wy, PDFReal llx, PDFReal lly, PDFReal urx, PDFReal ury)
{
    Q_UNUSED(wx);
    Q_UNUSED(wy);
    Q_UNUSED(llx);
    Q_UNUSED(lly);
    Q_UNUSED(urx);
    Q_UNUSED(ury);
}

void PDFPageContentProcessor::performBeginTransparencyGroup(ProcessOrder order, const PDFTransparencyGroup& transparencyGroup)
{
    Q_UNUSED(order);
    Q_UNUSED(transparencyGroup);
}

void PDFPageContentProcessor::performEndTransparencyGroup(ProcessOrder order, const PDFTransparencyGroup& transparencyGroup)
{
    Q_UNUSED(order);
    Q_UNUSED(transparencyGroup);
}

void PDFPageContentProcessor::performOutputCharacter(const PDFTextCharacterInfo& info)
{
    Q_UNUSED(info);
}

void PDFPageContentProcessor::performTextBegin(ProcessOrder order)
{
    Q_UNUSED(order);
}

void PDFPageContentProcessor::performTextEnd(ProcessOrder order)
{
    Q_UNUSED(order);
}

bool PDFPageContentProcessor::isContentKindSuppressed(ContentKind kind) const
{
    Q_UNUSED(kind);
    return false;
}

void PDFPageContentProcessor::setGraphicsState(const PDFPageContentProcessorState& state)
{
    m_graphicState = state;
    updateGraphicState();
}

bool PDFPageContentProcessor::isContentSuppressed() const
{
    return std::any_of(m_markedContentStack.cbegin(), m_markedContentStack.cend(), [](const MarkedContentState& state) { return state.contentSuppressed; });
}

PDFPageContentProcessor::PDFTransparencyGroup PDFPageContentProcessor::parseTransparencyGroup(const PDFObject& object)
{
    PDFTransparencyGroup group;

    if (const PDFDictionary* transparencyDictionary = m_document->getDictionaryFromObject(object))
    {
        const PDFObject& colorSpaceObject = m_document->getObject(transparencyDictionary->get("CS"));
        if (!colorSpaceObject.isNull())
        {
            group.colorSpacePointer = PDFAbstractColorSpace::createColorSpace(m_colorSpaceDictionary, m_document, colorSpaceObject);

            if (group.colorSpacePointer && !group.colorSpacePointer->isBlendColorSpace())
            {
                reportRenderError(RenderErrorType::Error, PDFTranslationContext::tr("Transparency group blending color space is invalid."));
                group.colorSpacePointer = nullptr;
            }
        }

        PDFDocumentDataLoaderDecorator loader(m_document);
        group.isolated = loader.readBooleanFromDictionary(transparencyDictionary, "I", false);
        group.knockout = loader.readBooleanFromDictionary(transparencyDictionary, "K", false);
    }

    return group;
}

void PDFPageContentProcessor::processContent(const QByteArray& content)
{
    PDFLexicalAnalyzer parser(content.constBegin(), content.constEnd());

    while (!parser.isAtEnd() && !isProcessingCancelled())
    {
        bool tokenFetched = false;
        PDFInteger oldParserPosition = parser.pos();

        try
        {
            PDFLexicalAnalyzer::Token token = parser.fetch();
            tokenFetched = true;

            switch (token.type)
            {
                case PDFLexicalAnalyzer::TokenType::Command:
                {
                    QByteArray command = token.data.toByteArray();

                    if (command == "BI")
                    {
                        // Strategy: We will try to find position of BI/ID/EI in the stream. If we can determine
                        // length of the stream explicitly, then we use explicit length. We also create a PDFObject
                        // from the inline image dictionary/image content stream and then process it like XObject.
                        PDFInteger operatorBIPosition = parser.pos();
                        PDFInteger operatorIDPosition = parser.findSubstring("ID", operatorBIPosition);
                        PDFInteger operatorEIPosition = parser.findSubstring("EI", operatorIDPosition);

                        // According the PDF 1.7 specification, single white space characters is after ID, then the byte
                        // immediately after it is interpreted as first byte of image data.
                        PDFInteger startDataPosition = operatorIDPosition + 3;

                        if (operatorIDPosition == -1 || operatorEIPosition == -1)
                        {
                            throw PDFException(PDFTranslationContext::tr("Invalid inline image dictionary, ID operator is missing."));
                        }

                        Q_ASSERT(operatorBIPosition < content.size());
                        Q_ASSERT(operatorIDPosition < content.size());
                        Q_ASSERT(operatorBIPosition <= operatorIDPosition);

                        PDFLexicalAnalyzer inlineImageLexicalAnalyzer(content.constBegin() + operatorBIPosition, content.constBegin() + operatorIDPosition);
                        PDFParser inlineImageParser([&inlineImageLexicalAnalyzer]{ return inlineImageLexicalAnalyzer.fetch(); });

                        constexpr std::pair<const char*, const char*> replacements[] =
                        {
                            { "BPC", "BitsPerComponent" },
                            { "CS", "ColorSpace" },
                            { "D", "Decode" },
                            { "DP", "DecodeParms" },
                            { "F", "Filter" },
                            { "H", "Height" },
                            { "IM", "ImageMask" },
                            { "I", "Interpolate" },
                            { "W", "Width" },
                            { "L", "Length" },
                            { "G", "DeviceGray" },
                            { "RGB", "DeviceRGB" },
                            { "CMYK", "DeviceCMYK" }
                        };

                        std::shared_ptr<PDFDictionary> dictionarySharedPointer = std::make_shared<PDFDictionary>();
                        PDFDictionary* dictionary = dictionarySharedPointer.get();

                        while (inlineImageParser.lookahead().type != PDFLexicalAnalyzer::TokenType::EndOfFile)
                        {
                            PDFObject nameObject = inlineImageParser.getObject();
                            PDFObject valueObject = inlineImageParser.getObject();

                            if (!nameObject.isName())
                            {
                                throw PDFException(PDFTranslationContext::tr("Expected name in the inline image dictionary stream."));
                            }

                            // Replace the name, if neccessary
                            QByteArray name = nameObject.getString();
                            for (auto [string, replacement] : replacements)
                            {
                                if (name == string)
                                {
                                    name = replacement;
                                    break;
                                }
                            }

                            dictionary->addEntry(PDFInplaceOrMemoryString(qMove(name)), qMove(valueObject));
                        }

                        PDFDocumentDataLoaderDecorator loader(m_document);
                        PDFInteger dataLength = 0;

                        if (dictionary->hasKey("Length"))
                        {
                            dataLength = loader.readIntegerFromDictionary(dictionary, "Length", 0);
                        }
                        else if (dictionary->hasKey("Filter"))
                        {
                            dataLength = -1;

                            // We will try to use stream filter hint
                            QByteArray filterName = loader.readNameFromDictionary(dictionary, "Filter");
                            if (!filterName.isEmpty())
                            {
                                dataLength = PDFStreamFilterStorage::getStreamDataLength(content, filterName, startDataPosition);
                            }

                            if (dataLength == -1)
                            {
                                // We will use EI operator position to determine stream length
                                dataLength = operatorEIPosition - startDataPosition;
                            }
                        }
                        else
                        {
                            // We will calculate stream size from the with/height and bit per component
                            const PDFInteger width = loader.readIntegerFromDictionary(dictionary, "Width", 0);
                            const PDFInteger height = loader.readIntegerFromDictionary(dictionary, "Height", 0);
                            const PDFInteger bpc = loader.readIntegerFromDictionary(dictionary, "BitsPerComponent", 8);

                            if (width <= 0 || height <= 0 || bpc <= 0)
                            {
                                throw PDFException(PDFTranslationContext::tr("Expected name in the inline image dictionary stream."));
                            }

                            const PDFInteger stride = (width * bpc + 7) / 8;
                            dataLength = stride * height;
                        }

                        // We will once more find the "EI" operator, due to recomputed dataLength.
                        operatorEIPosition = parser.findSubstring("EI", startDataPosition + dataLength);
                        if (operatorEIPosition == -1)
                        {
                            throw PDFException(PDFTranslationContext::tr("Invalid inline image stream."));
                        }

                        // We must seek after EI operator. Then we will paint the image. Because painting of image can throw exception,
                        // then we will paint the image AFTER we seek the position.
                        parser.seek(operatorEIPosition + 2);

                        QByteArray buffer = content.mid(startDataPosition, dataLength);
                        PDFStream imageStream(std::move(*dictionary), std::move(buffer));
                        paintXObjectImage(&imageStream);
                    }
                    else
                    {
                        // Process the command, then clear the operand stack
                        processCommand(command);
                    }

                    m_operands.clear();
                    break;
                }

                case PDFLexicalAnalyzer::TokenType::EndOfFile:
                {
                    // Do nothing, just break, we are at the end
                    break;
                }

                default:
                {
                    // Push the operand onto the operand stack
                    m_operands.push_back(std::move(token));
                    break;
                }
            }
        }
        catch (const PDFException& exception)
        {
            // If we get exception when parsing, and parser position is not advanced,
            // then we must advance it manually, otherwise we get infinite loop.
            if (!tokenFetched && oldParserPosition == parser.pos() && !parser.isAtEnd())
            {
                parser.seek(parser.pos() + 1);
            }

            m_operands.clear();
            m_errorList.append(PDFRenderError(RenderErrorType::Error, exception.getMessage()));
        }
        catch (const PDFRendererException &exception)
        {
            m_operands.clear();
            m_errorList.append(exception.getError());
        }
    }
}

void PDFPageContentProcessor::processContentStream(const PDFStream* stream)
{
    try
    {
        QByteArray content = m_document->getDecodedStream(stream);

        processContent(content);
    }
    catch (const PDFException& exception)
    {
        m_operands.clear();
        m_errorList.append(PDFRenderError(RenderErrorType::Error, exception.getMessage()));
    }
}

void PDFPageContentProcessor::processForm(const QTransform& matrix,
                                          const QRectF& boundingBox,
                                          const PDFObject& resources,
                                          const PDFObject& transparencyGroup,
                                          const QByteArray& content,
                                          PDFInteger formStructuralParent)
{
    PDFPageContentProcessorStateGuard guard(this);
    PDFTemporaryValueChange structuralParentChangeGuard(&m_structuralParentKey, formStructuralParent);

    std::unique_ptr<PDFTransparencyGroupGuard> guard2;
    if (transparencyGroup.isDictionary())
    {
        // Parse the transparency group
        const PDFDictionary* transparencyDictionary = transparencyGroup.getDictionary();
        PDFDocumentDataLoaderDecorator loader(m_document);
        PDFTransparencyGroup group;

        const PDFObject& colorSpaceObject = m_document->getObject(transparencyDictionary->get("CS"));
        if (!colorSpaceObject.isNull())
        {
            group.colorSpacePointer = PDFAbstractColorSpace::createColorSpace(m_colorSpaceDictionary, m_document, colorSpaceObject);
        }
        group.isolated = loader.readBooleanFromDictionary(transparencyDictionary, "I", false);
        group.knockout = loader.readBooleanFromDictionary(transparencyDictionary, "K", false);
        guard2.reset(new PDFTransparencyGroupGuard(this, qMove(group)));

        // If we are in transparency group, we must reset transparency settings in the graphic state.
        // Graphic state is then updated in the lines below.
        m_graphicState.setBlendMode(BlendMode::Normal);
        m_graphicState.setAlphaFilling(1.0);
        m_graphicState.setAlphaStroking(1.0);
        m_graphicState.setSoftMask(nullptr);
    }

    QTransform formMatrix = matrix * m_graphicState.getCurrentTransformationMatrix();
    m_graphicState.setCurrentTransformationMatrix(formMatrix);
    updateGraphicState();

    QTransform patternMatrix = formMatrix * m_pagePointToDevicePointMatrix;
    PDFTemporaryValueChange patternMatrixGuard(&m_patternBaseMatrix, patternMatrix);

    // If the clipping box is valid, then use clipping. Clipping box is in the form coordinate system
    if (boundingBox.isValid())
    {
        QPainterPath path;
        path.addRect(boundingBox);
        performClipping(path, path.fillRule());
    }

    // Initialize the resources, if we have them
    if (!resources.isNull())
    {
        initDictionaries(resources);
    }

    processContent(content);
}

void PDFPageContentProcessor::processPathPainting(const QPainterPath& path, bool stroke, bool fill, bool text, Qt::FillRule fillRule)
{
    if (isContentSuppressed() || (text && isContentKindSuppressed(ContentKind::Text)) || (!text && isContentKindSuppressed(ContentKind::Shapes)))
    {
        // Content is suppressed, do not paint anything
        return;
    }

    if ((!stroke && !fill) || path.isEmpty())
    {
        // No operation requested - either path is empty, or neither stroking or filling
        return;
    }

    if (fill)
    {
        if (const PDFPatternColorSpace* patternColorSpace = getGraphicState()->getFillColorSpace()->asPatternColorSpace())
        {
            const PDFPattern* pattern = patternColorSpace->getPattern();
            switch (pattern->getType())
            {
                case PatternType::Tiling:
                {
                    if (!isContentKindSuppressed(ContentKind::Tiling))
                    {
                        // Tiling is enabled
                        const PDFTilingPattern* tilingPattern = pattern->getTilingPattern();
                        processTillingPatternPainting(tilingPattern, path, patternColorSpace->getUncoloredPatternColorSpace(), patternColorSpace->getUncoloredPatternColor());
                    }
                    break;
                }

                case PatternType::Shading:
                {
                    if (!isContentKindSuppressed(ContentKind::Shading))
                    {
                        // Shading is enabled
                        PDFPageContentProcessorGraphicStateSaveRestoreGuard guard(this);
                        const PDFShadingPattern* shadingPattern = pattern->getShadingPattern();

                        // Apply pattern graphic state
                        const PDFObject& patternGraphicState = m_document->getObject(shadingPattern->getPatternGraphicState());
                        if (!patternGraphicState.isNull())
                        {
                            if (patternGraphicState.isDictionary())
                            {
                                processApplyGraphicState(patternGraphicState.getDictionary());
                            }
                            else
                            {
                                throw PDFRendererException(RenderErrorType::Error, PDFTranslationContext::tr("Shading pattern graphic state is invalid."));
                            }
                        }

                        // We must create a mesh and then draw pattern
                        PDFMeshQualitySettings settings = m_meshQualitySettings;
                        settings.deviceSpaceMeshingArea = getPageBoundingRectDeviceSpace();
                        settings.userSpaceToDeviceSpaceMatrix = getPatternBaseMatrix();
                        settings.initResolution();

                        if (!performPathPaintingUsingShading(path, false, true, shadingPattern))
                        {
                            PDFMesh mesh = shadingPattern->createMesh(settings, m_CMS, m_graphicState.getRenderingIntent(), this, m_operationControl);

                            // Now, merge the current path to the mesh clipping path
                            QPainterPath boundingPath = mesh.getBoundingPath();
                            if (boundingPath.isEmpty())
                            {
                                boundingPath = getCurrentWorldMatrix().map(path);
                            }
                            else
                            {
                                boundingPath = boundingPath.intersected(path);
                            }
                            mesh.setBoundingPath(boundingPath);

                            performMeshPainting(mesh);
                        }
                    }
                    break;
                }

                case PatternType::Invalid:
                {
                    throw PDFException(PDFTranslationContext::tr("Invalid pattern."));
                    break;
                }

                default:
                {
                    Q_ASSERT(false);
                    break;
                }
            }

            fill = false;
        }
    }

    if (stroke)
    {
        if (const PDFPatternColorSpace* patternColorSpace = getGraphicState()->getFillColorSpace()->asPatternColorSpace())
        {
            const PDFPattern* pattern = patternColorSpace->getPattern();
            switch (pattern->getType())
            {
                case PatternType::Tiling:
                {
                    if (!isContentKindSuppressed(ContentKind::Tiling))
                    {
                        // Tiling is enabled
                        const PDFTilingPattern* tilingPattern = pattern->getTilingPattern();

                        // We must stroke the path.
                        QPainterPathStroker stroker;
                        stroker.setCapStyle(m_graphicState.getLineCapStyle());
                        stroker.setWidth(m_graphicState.getLineWidth());
                        stroker.setMiterLimit(m_graphicState.getMitterLimit());
                        stroker.setJoinStyle(m_graphicState.getLineJoinStyle());

                        const PDFLineDashPattern& lineDashPattern = m_graphicState.getLineDashPattern();
                        if (!lineDashPattern.isSolid())
                        {
                            stroker.setDashPattern(lineDashPattern.createForQPen(m_graphicState.getLineWidth()));
                            stroker.setDashOffset(lineDashPattern.getDashOffset());
                        }
                        QPainterPath strokedPath = stroker.createStroke(path);
                        processTillingPatternPainting(tilingPattern, strokedPath, patternColorSpace->getUncoloredPatternColorSpace(), patternColorSpace->getUncoloredPatternColor());
                    }
                    break;
                }

                case PatternType::Shading:
                {
                    if (!isContentKindSuppressed(ContentKind::Shading))
                    {
                        // Shading is enabled
                        PDFPageContentProcessorGraphicStateSaveRestoreGuard guard(this);
                        const PDFShadingPattern* shadingPattern = pattern->getShadingPattern();

                        // Apply pattern graphic state
                        const PDFObject& patternGraphicState = m_document->getObject(shadingPattern->getPatternGraphicState());
                        if (!patternGraphicState.isNull())
                        {
                            if (patternGraphicState.isDictionary())
                            {
                                processApplyGraphicState(patternGraphicState.getDictionary());
                            }
                            else
                            {
                                throw PDFRendererException(RenderErrorType::Error, PDFTranslationContext::tr("Shading pattern graphic state is invalid."));
                            }
                        }

                        // We must create a mesh and then draw pattern
                        PDFMeshQualitySettings settings = m_meshQualitySettings;
                        settings.deviceSpaceMeshingArea = getPageBoundingRectDeviceSpace();
                        settings.userSpaceToDeviceSpaceMatrix = getPatternBaseMatrix();
                        settings.initResolution();

                        // We must stroke the path.
                        QPainterPathStroker stroker;
                        stroker.setCapStyle(m_graphicState.getLineCapStyle());
                        stroker.setWidth(m_graphicState.getLineWidth());
                        stroker.setMiterLimit(m_graphicState.getMitterLimit());
                        stroker.setJoinStyle(m_graphicState.getLineJoinStyle());

                        const PDFLineDashPattern& lineDashPattern = m_graphicState.getLineDashPattern();
                        if (!lineDashPattern.isSolid())
                        {
                            stroker.setDashPattern(lineDashPattern.createForQPen(m_graphicState.getLineWidth()));
                            stroker.setDashOffset(lineDashPattern.getDashOffset());
                        }
                        QPainterPath strokedPath = stroker.createStroke(path);

                        if (!performPathPaintingUsingShading(strokedPath, true, false, shadingPattern))
                        {
                            PDFMesh mesh = shadingPattern->createMesh(settings, m_CMS, m_graphicState.getRenderingIntent(), this, m_operationControl);

                            QPainterPath boundingPath = mesh.getBoundingPath();
                            if (boundingPath.isEmpty())
                            {
                                boundingPath = getCurrentWorldMatrix().map(strokedPath);
                            }
                            else
                            {
                                boundingPath = boundingPath.intersected(strokedPath);
                            }
                            mesh.setBoundingPath(boundingPath);

                            performMeshPainting(mesh);
                        }
                    }
                    break;
                }

                case PatternType::Invalid:
                {
                    throw PDFException(PDFTranslationContext::tr("Invalid pattern."));
                    break;
                }

                default:
                {
                    Q_ASSERT(false);
                    break;
                }
            }

            stroke = false;
        }
    }

    if (stroke || fill)
    {
        performPathPainting(path, stroke, fill, text, fillRule);
    }

    performFinishPathPainting();
}

void PDFPageContentProcessor::processTillingPatternPainting(const PDFTilingPattern* tilingPattern,
                                                            const QPainterPath& path,
                                                            PDFColorSpacePointer uncoloredPatternColorSpace,
                                                            PDFColor uncoloredPatternColor)
{
    PDFPageContentProcessorStateGuard guard(this);
    performClipping(path, path.fillRule());

    // Initialize resources
    const PDFObject& resources = tilingPattern->getResources();
    if (!resources.isNull())
    {
        initDictionaries(resources);
    }

    Q_ASSERT(m_pagePointToDevicePointMatrix.isInvertible());

    // Initialize rendering matrix
    QTransform patternMatrix = tilingPattern->getMatrix() * getPatternBaseMatrix();
    QTransform matrix = patternMatrix * m_pagePointToDevicePointMatrix.inverted();
    QTransform pathTransformationMatrix = m_graphicState.getCurrentTransformationMatrix() * matrix.inverted();
    m_graphicState.setCurrentTransformationMatrix(matrix);

    int uncoloredTilingPatternFlag = 0;

    // Initialize colors for uncolored color space pattern
    if (tilingPattern->getPaintingType() == PDFTilingPattern::PaintType::Uncolored)
    {
        if (!uncoloredPatternColorSpace)
        {
            throw PDFRendererException(RenderErrorType::Error, PDFTranslationContext::tr("Uncolored tiling pattern has not underlying color space."));
        }

        uncoloredTilingPatternFlag = 1;

        m_graphicState.setStrokeColorSpace(uncoloredPatternColorSpace);
        m_graphicState.setFillColorSpace(uncoloredPatternColorSpace);

        QColor color = uncoloredPatternColorSpace->getCheckedColor(uncoloredPatternColor, m_CMS, m_graphicState.getRenderingIntent(), this);
        m_graphicState.setStrokeColor(color, uncoloredPatternColor);
        m_graphicState.setFillColor(color, uncoloredPatternColor);
    }
    else
    {
        // Jakub Melka: According the specification, we set default color space and default color
        m_graphicState.setStrokeColorSpace(m_deviceGrayColorSpace);
        m_graphicState.setFillColorSpace(m_deviceGrayColorSpace);

        QColor color = m_deviceGrayColorSpace->getDefaultColor(m_CMS, m_graphicState.getRenderingIntent(), this);
        m_graphicState.setStrokeColor(color, m_deviceGrayColorSpace->getDefaultColorOriginal());
        m_graphicState.setFillColor(color, m_deviceGrayColorSpace->getDefaultColorOriginal());
    }

    updateGraphicState();

    // Mark uncolored flag, if we drawing uncolored color pattern
    PDFTemporaryValueChange guard2(&m_drawingUncoloredTilingPatternState, m_drawingUncoloredTilingPatternState + uncoloredTilingPatternFlag);

    // Tiling parameters
    const QRectF tilingArea = pathTransformationMatrix.map(path).boundingRect();
    const QRectF boundingBox = tilingPattern->getBoundingBox();
    const PDFReal xStep = qAbs(tilingPattern->getXStep());
    const PDFReal yStep = qAbs(tilingPattern->getYStep());
    const QByteArray& content = tilingPattern->getContent();
    QPainterPath boundingPath;
    boundingPath.addRect(boundingBox);

    // Draw the tiling
    const PDFInteger columns = qMax<PDFInteger>(qCeil(tilingArea.width() / xStep), 1);
    const PDFInteger rows = qMax<PDFInteger>(qCeil(tilingArea.height() / yStep), 1);

    QTransform baseTransformationMatrix = m_graphicState.getCurrentTransformationMatrix();
    for (PDFInteger column = 0; column < columns; ++column)
    {
        for (PDFInteger row = 0; row < rows; ++row)
        {
            PDFPageContentProcessorGraphicStateSaveRestoreGuard guard3(this);

            QTransform transformationMatrix = baseTransformationMatrix;
            transformationMatrix.translate(tilingArea.left(), tilingArea.top());
            transformationMatrix.translate(column * xStep, row * yStep);

            QTransform currentPatternMatrix = transformationMatrix * m_pagePointToDevicePointMatrix;
            PDFTemporaryValueChange patternMatrixGuard(&m_patternBaseMatrix, currentPatternMatrix);

            m_graphicState.setCurrentTransformationMatrix(transformationMatrix);
            updateGraphicState();

            performClipping(boundingPath, boundingPath.fillRule());
            processContent(content);

            if (isProcessingCancelled())
            {
                break;
            }
        }

        if (isProcessingCancelled())
        {
            break;
        }
    }
}

void PDFPageContentProcessor::processCommand(const QByteArray& command)
{
    Operator op = Operator::Invalid;

    // Find the command in the command array
    for (const std::pair<const char*, PDFPageContentProcessor::Operator>& operatorDescriptor : operators)
    {
        if (command == operatorDescriptor.first)
        {
            op = operatorDescriptor.second;
            break;
        }
    }

    switch (op)
    {
        case Operator::SetLineWidth:
        {
            invokeOperator(&PDFPageContentProcessor::operatorSetLineWidth);
            break;
        }

        case Operator::SetLineCap:
        {
            invokeOperator(&PDFPageContentProcessor::operatorSetLineCap);
            break;
        }

        case Operator::SetLineJoin:
        {
            invokeOperator(&PDFPageContentProcessor::operatorSetLineJoin);
            break;
        }

        case Operator::SetMitterLimit:
        {
            invokeOperator(&PDFPageContentProcessor::operatorSetMitterLimit);
            break;
        }

        case Operator::SetLineDashPattern:
        {
            invokeOperator(&PDFPageContentProcessor::operatorSetLineDashPattern);
            break;
        }

        case Operator::SetRenderingIntent:
        {
            invokeOperator(&PDFPageContentProcessor::operatorSetRenderingIntent);
            break;
        }

        case Operator::SetFlatness:
        {
            invokeOperator(&PDFPageContentProcessor::operatorSetFlatness);
            break;
        }

        case Operator::SetGraphicState:
        {
            invokeOperator(&PDFPageContentProcessor::operatorSetGraphicState);
            break;
        }

        case Operator::SaveGraphicState:
        {
            operatorSaveGraphicState();
            break;
        }

        case Operator::RestoreGraphicState:
        {
            operatorRestoreGraphicState();
            break;
        }

        case Operator::AdjustCurrentTransformationMatrix:
        {
            invokeOperator(&PDFPageContentProcessor::operatorAdjustCurrentTransformationMatrix);
            break;
        }

        case Operator::MoveCurrentPoint:
        {
            invokeOperator(&PDFPageContentProcessor::operatorMoveCurrentPoint);
            break;
        }

        case Operator::LineTo:
        {
            invokeOperator(&PDFPageContentProcessor::operatorLineTo);
            break;
        }

        case Operator::Bezier123To:
        {
            invokeOperator(&PDFPageContentProcessor::operatorBezier123To);
            break;
        }

        case Operator::Bezier23To:
        {
            invokeOperator(&PDFPageContentProcessor::operatorBezier23To);
            break;
        }

        case Operator::Bezier13To:
        {
            invokeOperator(&PDFPageContentProcessor::operatorBezier13To);
            break;
        }
        case Operator::EndSubpath:
        {
            // Call directly, no parameters involved
            operatorEndSubpath();
            break;
        }

        case Operator::Rectangle:
        {
            invokeOperator(&PDFPageContentProcessor::operatorRectangle);
            break;
        }

        case Operator::PathStroke:
        {
            operatorPathStroke();
            break;
        }

        case Operator::PathCloseStroke:
        {
            operatorPathCloseStroke();
            break;
        }

        case Operator::PathFillWinding:
        case Operator::PathFillWinding2:
        {
            operatorPathFillWinding();
            break;
        }

        case Operator::PathFillEvenOdd:
        {
            operatorPathFillEvenOdd();
            break;
        }

        case Operator::PathFillStrokeWinding:
        {
            operatorPathFillStrokeWinding();
            break;
        }

        case Operator::PathFillStrokeEvenOdd:
        {
            operatorPathFillStrokeEvenOdd();
            break;
        }

        case Operator::PathCloseFillStrokeWinding:
        {
            operatorPathCloseFillStrokeWinding();
            break;
        }

        case Operator::PathCloseFillStrokeEvenOdd:
        {
            operatorPathCloseFillStrokeEvenOdd();
            break;
        }

        case Operator::PathClear:
        {
            operatorPathClear();
            break;
        }

        case Operator::ClipEvenOdd:
        {
            operatorClipEvenOdd();
            break;
        }

        case Operator::ClipWinding:
        {
            operatorClipWinding();
            break;
        }

        case Operator::Type3FontSetOffset:
        {
            // d0, set width information, see PDF 1.7 Reference, Table 5.10
            invokeOperator(&PDFPageContentProcessor::operatorType3FontSetOffset);
            break;
        }

        case Operator::Type3FontSetOffsetAndBB:
        {
            // d1, set offset and glyph bounding box
            invokeOperator(&PDFPageContentProcessor::operatorType3FontSetOffsetAndBB);
            break;
        }

        case Operator::ColorSetStrokingColorSpace:
        {
            // CS, set current color space for stroking operations
            invokeOperator(&PDFPageContentProcessor::operatorColorSetStrokingColorSpace);
            break;
        }

        case Operator::ColorSetFillingColorSpace:
        {
            // cs, set current color space for filling operations
            invokeOperator(&PDFPageContentProcessor::operatorColorSetFillingColorSpace);
            break;
        }

        case Operator::ColorSetStrokingColor:
        {
            // SC, set current stroking color
            operatorColorSetStrokingColor();
            break;
        }

        case Operator::ColorSetStrokingColorN:
        {
            // SCN, same as SC, but also supports Pattern, Separation, DeviceN and ICCBased color spaces
            operatorColorSetStrokingColorN();
            break;
        }

        case Operator::ColorSetFillingColor:
        {
            // sc, set current filling color
            operatorColorSetFillingColor();
            break;
        }

        case Operator::ColorSetFillingColorN:
        {
            // scn, same as sc, but also supports Pattern, Separation, DeviceN and ICCBased color spaces
            operatorColorSetFillingColorN();
            break;
        }

        case Operator::ColorSetDeviceGrayStroking:
        {
            // G, set DeviceGray color space for stroking color and set color
            invokeOperator(&PDFPageContentProcessor::operatorColorSetDeviceGrayStroking);
            break;
        }

        case Operator::ColorSetDeviceGrayFilling:
        {
            // g, set DeviceGray color space for filling color and set color
            invokeOperator(&PDFPageContentProcessor::operatorColorSetDeviceGrayFilling);
            break;
        }

        case Operator::ColorSetDeviceRGBStroking:
        {
            // RG, set DeviceRGB color space for stroking color and set color
            invokeOperator(&PDFPageContentProcessor::operatorColorSetDeviceRGBStroking);
            break;
        }

        case Operator::ColorSetDeviceRGBFilling:
        {
            // rg, set DeviceRGB color space for filling color and set color
            invokeOperator(&PDFPageContentProcessor::operatorColorSetDeviceRGBFilling);
            break;
        }

        case Operator::ColorSetDeviceCMYKStroking:
        {
            // K, set DeviceCMYK color space for stroking color and set color
            invokeOperator(&PDFPageContentProcessor::operatorColorSetDeviceCMYKStroking);
            break;
        }

        case Operator::ColorSetDeviceCMYKFilling:
        {
            // k, set DeviceCMYK color space for filling color and set color
            invokeOperator(&PDFPageContentProcessor::operatorColorSetDeviceCMYKFilling);
            break;
        }

        case Operator::TextBegin:
        {
            // BT, begin text object, initialize text matrices, cannot be nested
            operatorTextBegin();
            break;
        }

        case Operator::TextEnd:
        {
            // ET, end text object, cannot be nested
            operatorTextEnd();
            break;
        }

        case Operator::TextSetCharacterSpacing:
        {
            // Tc, set text character spacing
            invokeOperator(&PDFPageContentProcessor::operatorTextSetCharacterSpacing);
            break;
        }

        case Operator::TextSetWordSpacing:
        {
            // Tw, set text word spacing
            invokeOperator(&PDFPageContentProcessor::operatorTextSetWordSpacing);
            break;
        }

        case Operator::TextSetHorizontalScale:
        {
            // Tz, set text horizontal scaling (in percents, 100% = normal scaling)
            invokeOperator(&PDFPageContentProcessor::operatorTextSetHorizontalScale);
            break;
        }

        case Operator::TextSetLeading:
        {
            // TL, set text leading
            invokeOperator(&PDFPageContentProcessor::operatorTextSetLeading);
            break;
        }

        case Operator::TextSetFontAndFontSize:
        {
            // Tf, set text font (name from dictionary) and its size
            invokeOperator(&PDFPageContentProcessor::operatorTextSetFontAndFontSize);
            break;
        }

        case Operator::TextSetRenderMode:
        {
            // Tr, set text render mode
            invokeOperator(&PDFPageContentProcessor::operatorTextSetRenderMode);
            break;
        }

        case Operator::TextSetRise:
        {
            // Ts, set text rise
            invokeOperator(&PDFPageContentProcessor::operatorTextSetRise);
            break;
        }

        case Operator::TextMoveByOffset:
        {
            // Td, move by offset
            invokeOperator(&PDFPageContentProcessor::operatorTextMoveByOffset);
            break;
        }

        case Operator::TextSetLeadingAndMoveByOffset:
        {
            // TD, sets text leading and moves by offset, x y TD is equivalent to sequence -y TL x y Td
            invokeOperator(&PDFPageContentProcessor::operatorTextSetLeadingAndMoveByOffset);
            break;
        }

        case Operator::TextSetMatrix:
        {
            // Tm, set text matrix
            invokeOperator(&PDFPageContentProcessor::operatorTextSetMatrix);
            break;
        }

        case Operator::TextMoveByLeading:
        {
            // T*, moves text by leading, equivalent to 0 leading Td
            operatorTextMoveByLeading();
            break;
        }

        case Operator::TextShowTextString:
        {
            // Tj, show text string
            invokeOperator(&PDFPageContentProcessor::operatorTextShowTextString);
            break;
        }

        case Operator::TextShowTextIndividualSpacing:
        {
            // TJ, show text, allow individual text spacing
            invokeOperator(&PDFPageContentProcessor::operatorTextShowTextIndividualSpacing);
            break;
        }

        case Operator::TextNextLineShowText:
        {
            // ', move to the next line and show text ("string '" is equivalent to "T* string Tj")
            invokeOperator(&PDFPageContentProcessor::operatorTextNextLineShowText);
            break;
        }

        case Operator::TextSetSpacingAndShowText:
        {
            // ", move to the next line, set spacing and show text (equivalent to sequence "w1 Tw w2 Tc string '")
            invokeOperator(&PDFPageContentProcessor::operatorTextSetSpacingAndShowText);
            break;
        }

        case Operator::PaintXObject:
        {
            // Do, paint the X Object (image, form, ...)
            invokeOperator(&PDFPageContentProcessor::operatorPaintXObject);
            break;
        }

        case Operator::ShadingPaintShape:
        {
            // sh, paint shape
            invokeOperator(&PDFPageContentProcessor::operatorShadingPaintShape);
            break;
        }

        case Operator::MarkedContentPoint:
        {
            // MP, marked content point
            invokeOperator(&PDFPageContentProcessor::operatorMarkedContentPoint);
            break;
        }

        case Operator::MarkedContentPointWithProperties:
        {
            // DP, marked content point with properties
            operatorMarkedContentPointWithProperties(readOperand<PDFOperandName>(0), readObjectFromOperandStack(1));
            break;
        }

        case Operator::MarkedContentBegin:
        {
            // BMC, begin of sequence of marked content
            invokeOperator(&PDFPageContentProcessor::operatorMarkedContentBegin);
            break;
        }

        case Operator::MarkedContentBeginWithProperties:
        {
            // BDC, begin of sequence of marked content with properties
            operatorMarkedContentBeginWithProperties(readOperand<PDFOperandName>(0), readObjectFromOperandStack(1));
            break;
        }

        case Operator::MarkedContentEnd:
        {
            // EMC, end of marked content sequence
            operatorMarkedContentEnd();
            break;
        }

        case Operator::CompatibilityBegin:
        {
            operatorCompatibilityBegin();
            break;
        }

        case Operator::CompatibilityEnd:
        {
            operatorCompatibilityEnd();
            break;
        }

        case Operator::Invalid:
        {
            m_errorList.append(PDFRenderError(RenderErrorType::Error, PDFTranslationContext::tr("Unknown operator '%1'.").arg(QString::fromLatin1(command))));
            break;
        }

        default:
        {
            m_errorList.append(PDFRenderError(RenderErrorType::NotImplemented, PDFTranslationContext::tr("Not implemented operator '%1'.").arg(QString::fromLatin1(command))));
            break;
        }
    }
}

QPointF PDFPageContentProcessor::getCurrentPoint() const
{
    const int elementCount = m_currentPath.elementCount();
    if (elementCount > 0)
    {
        QPainterPath::Element element = m_currentPath.elementAt(elementCount - 1);
        return QPointF(element.x, element.y);
    }
    else
    {
        throw PDFRendererException(RenderErrorType::Error, PDFTranslationContext::tr("Current point of path is not set. Path is empty."));
    }
}

void PDFPageContentProcessor::updateGraphicState()
{
    if (m_graphicState.getStateFlags())
    {
        performUpdateGraphicsState(m_graphicState);
        m_graphicState.setStateFlags(PDFPageContentProcessorState::StateUnchanged);
    }
}

void PDFPageContentProcessor::operatorSetLineWidth(PDFReal lineWidth)
{
    lineWidth = qMax(0.0, lineWidth);
    m_graphicState.setLineWidth(lineWidth);
    updateGraphicState();
}

Qt::PenCapStyle PDFPageContentProcessor::convertLineCapToPenCapStyle(PDFInteger lineCap)
{
    lineCap = qBound<PDFInteger>(PDFInteger(0), lineCap, PDFInteger(2));

    Qt::PenCapStyle penCapStyle = Qt::FlatCap;
    switch (lineCap)
    {
        case 0:
        {
            penCapStyle = Qt::FlatCap;
            break;
        }

        case 1:
        {
            penCapStyle = Qt::RoundCap;
            break;
        }

        case 2:
        {
            penCapStyle = Qt::SquareCap;
            break;
        }

        default:
        {
            // This case can't occur, because we are correcting invalid values above.
            Q_ASSERT(false);
            break;
        }
    }

    return penCapStyle;
}

PDFInteger PDFPageContentProcessor::convertPenCapStyleToLineCap(Qt::PenCapStyle penCapStyle)
{
    switch (penCapStyle)
    {
        case Qt::FlatCap:
            return 0;
        case Qt::SquareCap:
            return 2;
        case Qt::RoundCap:
            return 1;

        default:
            break;
    }

    // Invalid pen cap style occured
    Q_ASSERT(false);
    return 0;
}

void PDFPageContentProcessor::operatorSetLineCap(PDFInteger lineCap)
{
    const Qt::PenCapStyle penCapStyle = convertLineCapToPenCapStyle(lineCap);
    m_graphicState.setLineCapStyle(penCapStyle);
    updateGraphicState();
}

Qt::PenJoinStyle PDFPageContentProcessor::convertLineJoinToPenJoinStyle(PDFInteger lineJoin)
{
    lineJoin = qBound<PDFInteger>(PDFInteger(0), lineJoin, PDFInteger(2));

    Qt::PenJoinStyle penJoinStyle = Qt::MiterJoin;
    switch (lineJoin)
    {
        case 0:
        {
            penJoinStyle = Qt::MiterJoin;
            break;
        }

        case 1:
        {
            penJoinStyle = Qt::RoundJoin;
            break;
        }

        case 2:
        {
            penJoinStyle = Qt::BevelJoin;
            break;
        }

        default:
        {
            // This case can't occur, because we are correcting invalid values above.
            Q_ASSERT(false);
            break;
        }
    }

    return penJoinStyle;
}

PDFInteger PDFPageContentProcessor::convertPenJoinStyleToLineJoin(Qt::PenJoinStyle penJoinStyle)
{
    switch (penJoinStyle)
    {
        case Qt::MiterJoin:
            return 0;
        case Qt::BevelJoin:
            return 2;
        case Qt::RoundJoin:
            return 1;

        default:
            break;
    }

    // Invalid pen join style occured
    Q_ASSERT(false);
    return 0;
}

void PDFPageContentProcessor::operatorSetLineJoin(PDFInteger lineJoin)
{
    const Qt::PenJoinStyle penJoinStyle = convertLineJoinToPenJoinStyle(lineJoin);
    m_graphicState.setLineJoinStyle(penJoinStyle);
    updateGraphicState();
}

void PDFPageContentProcessor::operatorSetMitterLimit(PDFReal mitterLimit)
{
    mitterLimit = qMax(0.0, mitterLimit);
    m_graphicState.setMitterLimit(mitterLimit);
    updateGraphicState();
}

void PDFPageContentProcessor::operatorSetLineDashPattern()
{
    // Operand stack must be of this form [ ... numbers ... ] offset. We check it.
    // Minimal number of operands is [] 0.

    if (m_operands.size() < 3)
    {
        throw PDFRendererException(RenderErrorType::Error, PDFTranslationContext::tr("Invalid line dash pattern."));
    }

    // Now, we have at least 3 arguments. Check we have an array
    if (m_operands[0].type != PDFLexicalAnalyzer::TokenType::ArrayStart ||
        m_operands[m_operands.size() - 2].type != PDFLexicalAnalyzer::TokenType::ArrayEnd)
    {
        throw PDFRendererException(RenderErrorType::Error, PDFTranslationContext::tr("Invalid line dash pattern."));
    }

    const size_t dashArrayStartIndex = 1;
    const size_t dashArrayEndIndex = m_operands.size() - 2;
    const size_t dashOffsetIndex = m_operands.size() - 1;

    std::vector<PDFReal> dashArray;
    dashArray.reserve(dashArrayEndIndex - dashArrayStartIndex);
    for (size_t i = dashArrayStartIndex; i < dashArrayEndIndex; ++i)
    {
        dashArray.push_back(readOperand<PDFReal>(i));
    }

    const PDFReal dashOffset = readOperand<PDFReal>(dashOffsetIndex);
    PDFLineDashPattern pattern(std::move(dashArray), dashOffset);
    m_graphicState.setLineDashPattern(std::move(pattern));
    updateGraphicState();
}

void PDFPageContentProcessor::operatorSetRenderingIntent(PDFOperandName intent)
{
    setRenderingIntentByName(intent.name);
    updateGraphicState();
}

void PDFPageContentProcessor::operatorSetFlatness(PDFReal flatness)
{
    flatness = qBound(0.0, flatness, 100.0);
    m_graphicState.setFlatness(flatness);
    updateGraphicState();
}

void PDFPageContentProcessor::setRenderingIntentByName(QByteArray renderingIntentName)
{
    RenderingIntent renderingIntent = RenderingIntent::Unknown;

    if (renderingIntentName == "Perceptual")
    {
        renderingIntent = RenderingIntent::Perceptual;
    }
    else if (renderingIntentName == "AbsoluteColorimetric")
    {
        renderingIntent = RenderingIntent::AbsoluteColorimetric;
    }
    else if (renderingIntentName == "RelativeColorimetric")
    {
        renderingIntent = RenderingIntent::RelativeColorimetric;
    }
    else if (renderingIntentName == "Saturation")
    {
        renderingIntent = RenderingIntent::Saturation;
    }
    m_graphicState.setRenderingIntent(renderingIntent);
    m_graphicState.setRenderingIntentName(renderingIntentName);
}

void PDFPageContentProcessor::finishMarkedContent()
{
    if (!m_markedContentStack.empty())
    {
        m_errorList.append(PDFRenderError(RenderErrorType::Error, PDFTranslationContext::tr("Marked content is not well formed (not enough EMC operators).")));
    }

    while (!m_markedContentStack.empty())
    {
        operatorMarkedContentEnd();
    }
}

void PDFPageContentProcessor::setOperationControl(const PDFOperationControl* newOperationControl)
{
    m_operationControl = newOperationControl;
}

bool PDFPageContentProcessor::isProcessingCancelled() const
{
    return m_operationControl && m_operationControl->isOperationCancelled();
}

void PDFPageContentProcessor::reportRenderErrorOnce(RenderErrorType type, QString message)
{
    if (!m_onceReportedErrors.count(message))
    {
        m_onceReportedErrors.insert(message);
        reportRenderError(type, message);
    }
}

void PDFPageContentProcessor::processApplyGraphicState(const PDFDictionary* graphicStateDictionary)
{
    PDFDocumentDataLoaderDecorator loader(m_document);
    const PDFReal lineWidth = loader.readNumberFromDictionary(graphicStateDictionary, "LW", m_graphicState.getLineWidth());
    const Qt::PenCapStyle penCapStyle = convertLineCapToPenCapStyle(loader.readNumberFromDictionary(graphicStateDictionary, "LC", convertPenCapStyleToLineCap(m_graphicState.getLineCapStyle())));
    const Qt::PenJoinStyle penJoinStyle = convertLineJoinToPenJoinStyle(loader.readNumberFromDictionary(graphicStateDictionary, "LJ", convertPenJoinStyleToLineJoin(m_graphicState.getLineJoinStyle())));
    const PDFReal mitterLimit = loader.readNumberFromDictionary(graphicStateDictionary, "ML", m_graphicState.getMitterLimit());

    const PDFObject& lineDashPatternObject = m_document->getObject(graphicStateDictionary->get("D"));
    if (lineDashPatternObject.isArray())
    {
        const PDFArray* lineDashPatternDefinitionArray = lineDashPatternObject.getArray();
        if (lineDashPatternDefinitionArray->getCount() == 2)
        {
            PDFLineDashPattern pattern(loader.readNumberArray(lineDashPatternDefinitionArray->getItem(0)), loader.readNumber(lineDashPatternDefinitionArray->getItem(1), 0.0));
            pattern.fix();
            m_graphicState.setLineDashPattern(pattern);
        }
    }

    const PDFReal flatness = loader.readNumberFromDictionary(graphicStateDictionary, "FL", m_graphicState.getFlatness());
    const PDFReal smoothness = loader.readNumberFromDictionary(graphicStateDictionary, "SM", m_graphicState.getSmoothness());
    const bool textKnockout = loader.readBooleanFromDictionary(graphicStateDictionary, "TK", m_graphicState.getTextKnockout());
    const PDFReal strokingAlpha = loader.readNumberFromDictionary(graphicStateDictionary, "CA", m_graphicState.getAlphaStroking());
    const PDFReal fillingAlpha = loader.readNumberFromDictionary(graphicStateDictionary, "ca", m_graphicState.getAlphaFilling());
    QByteArray blendModeName = loader.readNameFromDictionary(graphicStateDictionary, "BM");
    QByteArray renderingIntentName = loader.readNameFromDictionary(graphicStateDictionary, "RI");
    const bool alphaIsShape = loader.readBooleanFromDictionary(graphicStateDictionary, "AIS", m_graphicState.getAlphaIsShape());
    const bool strokeAdjustment = loader.readBooleanFromDictionary(graphicStateDictionary, "SA", m_graphicState.getStrokeAdjustment());
    const PDFDictionary* softMask = graphicStateDictionary->hasKey("SMask") ? m_document->getDictionaryFromObject(graphicStateDictionary->get("SMask")) : m_graphicState.getSoftMask();

    // We will try to get blend mode name from the array (if BM is array). First supported blend mode should
    // be used. In PDF 2.0, array is deprecated, so for backward compatibility, we extract first blend mode
    // name from the array and try to use it.
    if (blendModeName.isEmpty())
    {
        std::vector<QByteArray> blendModeNames = loader.readNameArrayFromDictionary(graphicStateDictionary, "BM");
        if (!blendModeNames.empty())
        {
            blendModeName = qMove(blendModeNames.front());
        }
    }

    if (!blendModeName.isEmpty())
    {
        BlendMode blendMode = PDFBlendModeInfo::getBlendMode(blendModeName);

        if (blendMode == BlendMode::Invalid)
        {
            blendMode = BlendMode::Normal;
            m_errorList.append(PDFRenderError(RenderErrorType::NotImplemented, PDFTranslationContext::tr("Blend mode '%1' is invalid.").arg(QString::fromLatin1(blendModeName))));
        }
        m_graphicState.setBlendMode(blendMode);
    }

    if (!renderingIntentName.isEmpty())
    {
        setRenderingIntentByName(renderingIntentName);
    }

    PDFOverprintMode overprintMode = m_graphicState.getOverprintMode();
    overprintMode.overprintMode = loader.readIntegerFromDictionary(graphicStateDictionary, "OPM", overprintMode.overprintMode);

    // Overprint for filling is ruled by overprint for stroking, if "op" is not present, according to the specification
    overprintMode.overprintStroking = loader.readBooleanFromDictionary(graphicStateDictionary, "OP", overprintMode.overprintStroking);
    overprintMode.overprintFilling = loader.readBooleanFromDictionary(graphicStateDictionary, "op", overprintMode.overprintStroking);

    constexpr std::array blackPointCompensationModes = {
        std::pair<const char*, BlackPointCompensationMode>{ "Default", BlackPointCompensationMode::Default },
        std::pair<const char*, BlackPointCompensationMode>{ "ON", BlackPointCompensationMode::ON },
        std::pair<const char*, BlackPointCompensationMode>{ "OFF", BlackPointCompensationMode::OFF },
    };

    BlackPointCompensationMode blackPointCompensationMode = m_graphicState.getBlackPointCompensationMode();
    if (graphicStateDictionary->hasKey("UseBlackPtComp"))
    {
        blackPointCompensationMode = loader.readEnumByName(graphicStateDictionary->get("UseBlackPtComp"), blackPointCompensationModes.cbegin(), blackPointCompensationModes.cend(), BlackPointCompensationMode::Default);
    }

    PDFObject blackGenerationFunctionObject = m_graphicState.getBlackGenerationFunction();
    if (graphicStateDictionary->hasKey("BG") || graphicStateDictionary->hasKey("BG2"))
    {
        blackGenerationFunctionObject = m_document->getObject(graphicStateDictionary->get("BG2"));
        if (blackGenerationFunctionObject.isNull())
        {
            blackGenerationFunctionObject = m_document->getObject(graphicStateDictionary->get("BG"));
        }
    }

    PDFObject undercolorRemovalFunctionObject = m_graphicState.getUndercolorRemovalFunction();
    if (graphicStateDictionary->hasKey("UCR") || graphicStateDictionary->hasKey("UCR2"))
    {
        undercolorRemovalFunctionObject = m_document->getObject(graphicStateDictionary->get("UCR2"));
        if (undercolorRemovalFunctionObject.isNull())
        {
            undercolorRemovalFunctionObject = m_document->getObject(graphicStateDictionary->get("UCR"));
        }
    }

    PDFObject transferFunctionObject = m_graphicState.getTransferFunction();
    if (graphicStateDictionary->hasKey("TR") || graphicStateDictionary->hasKey("TR2"))
    {
        transferFunctionObject = m_document->getObject(graphicStateDictionary->get("TR2"));
        if (transferFunctionObject.isNull())
        {
            transferFunctionObject = m_document->getObject(graphicStateDictionary->get("TR"));
        }
    }

    PDFObject halftoneObject = graphicStateDictionary->hasKey("HT") ? m_document->getObject(graphicStateDictionary->get("HT")) : m_graphicState.getHalftone();

    QPointF halftoneOrigin = m_graphicState.getHalftoneOrigin();
    if (graphicStateDictionary->hasKey("HTO"))
    {
        std::vector<PDFReal> halftoneOriginArray = loader.readNumberArrayFromDictionary(graphicStateDictionary, "HTO");
        if (halftoneOriginArray.size() >= 2)
        {
            halftoneOrigin = QPointF(halftoneOriginArray[0], halftoneOriginArray[1]);
        }
    }

    m_graphicState.setLineWidth(lineWidth);
    m_graphicState.setLineCapStyle(penCapStyle);
    m_graphicState.setLineJoinStyle(penJoinStyle);
    m_graphicState.setMitterLimit(mitterLimit);
    m_graphicState.setFlatness(flatness);
    m_graphicState.setSmoothness(smoothness);
    m_graphicState.setTextKnockout(textKnockout);
    m_graphicState.setAlphaStroking(strokingAlpha);
    m_graphicState.setAlphaFilling(fillingAlpha);
    m_graphicState.setOverprintMode(overprintMode);
    m_graphicState.setAlphaIsShape(alphaIsShape);
    m_graphicState.setStrokeAdjustment(strokeAdjustment);
    m_graphicState.setSoftMask(softMask);
    m_graphicState.setBlackPointCompensationMode(blackPointCompensationMode);
    m_graphicState.setBlackGenerationFunction(qMove(blackGenerationFunctionObject));
    m_graphicState.setUndercolorRemovalFunction(qMove(undercolorRemovalFunctionObject));
    m_graphicState.setTransferFunction(qMove(transferFunctionObject));
    m_graphicState.setHalftone(qMove(halftoneObject));
    m_graphicState.setHalftoneOrigin(halftoneOrigin);
    updateGraphicState();

    if (graphicStateDictionary->hasKey("Font"))
    {
        const PDFObject& fontObject = m_document->getObject(graphicStateDictionary->get("Font"));
        if (fontObject.isArray())
        {
            const PDFArray* fontObjectArray = fontObject.getArray();
            if (fontObjectArray->getCount() == 2)
            {
                PDFOperandName operandName;
                operandName.name = loader.readName(fontObjectArray->getItem(0));
                operatorTextSetFontAndFontSize(operandName, loader.readNumber(fontObjectArray->getItem(1), 1.0));
            }
        }
    }
}

void PDFPageContentProcessor::operatorSetGraphicState(PDFOperandName dictionaryName)
{
    if (m_extendedGraphicStateDictionary)
    {
        if (m_extendedGraphicStateDictionary->hasKey(dictionaryName.name))
        {
            const PDFObject& graphicStateObject = m_document->getObject(m_extendedGraphicStateDictionary->get(dictionaryName.name));
            if (graphicStateObject.isDictionary())
            {
                const PDFDictionary* graphicStateDictionary = graphicStateObject.getDictionary();
                processApplyGraphicState(graphicStateDictionary);
            }
            else
            {
                throw PDFRendererException(RenderErrorType::Error, PDFTranslationContext::tr("Graphic state '%1' found, but invalid in resource dictionary.").arg(QString::fromLatin1(dictionaryName.name)));
            }
        }
        else
        {
            throw PDFRendererException(RenderErrorType::Error, PDFTranslationContext::tr("Graphic state '%1' not found in resource dictionary.").arg(QString::fromLatin1(dictionaryName.name)));
        }
    }
    else
    {
        throw PDFRendererException(RenderErrorType::Error, PDFTranslationContext::tr("Invalid graphic state resource dictionary."));
    }
}

void PDFPageContentProcessor::operatorSaveGraphicState()
{
    performSaveGraphicState(ProcessOrder::BeforeOperation);
    m_stack.push(m_graphicState);
    m_stack.top().setStateFlags(PDFPageContentProcessorState::StateUnchanged);
    performSaveGraphicState(ProcessOrder::AfterOperation);
}

void PDFPageContentProcessor::operatorRestoreGraphicState()
{
    if (m_stack.empty())
    {
        throw PDFRendererException(RenderErrorType::Error, PDFTranslationContext::tr("Trying to restore graphic state more times than it was saved."));
    }

    performRestoreGraphicState(ProcessOrder::BeforeOperation);
    m_graphicState = m_stack.top();
    m_stack.pop();
    updateGraphicState();
    performRestoreGraphicState(ProcessOrder::AfterOperation);
}

void PDFPageContentProcessor::operatorAdjustCurrentTransformationMatrix(PDFReal a, PDFReal b, PDFReal c, PDFReal d, PDFReal e, PDFReal f)
{
    // We will comment following equation:
    //  Adobe PDF Reference 1.7 says, that we have this transformation using coefficient a, b, c, d, e and f:
    //                             [ a, b, 0 ]
    //  [x', y', 1] = [ x, y, 1] * [ c, d, 0 ]
    //                             [ e, f, 1 ]
    // If we transpose this equation (we want this, because Qt uses transposed matrices (QTransform).
    // So, we will get following result:
    //
    // [ x' ]   [ a, c, e]    [ x ]
    // [ y' ] = [ b, d, f] *  [ y ]
    // [ 1  ]   [ 0, 0, 1]    [ 1 ]
    //
    // So, it is obvious, than we will have following coefficients:
    //  m_11 = a, m_21 = c, dx = e
    //  m_12 = b, m_22 = d, dy = f
    //
    // We must also check, that matrix is invertible. If it is not, then we will throw exception
    // to avoid errors later (for some operations, we assume matrix is invertible).

    QTransform matrix(a, b, c, d, e, f);
    QTransform transformMatrix = matrix * m_graphicState.getCurrentTransformationMatrix();

    if (!transformMatrix.isInvertible())
    {
        throw PDFRendererException(RenderErrorType::Error, PDFTranslationContext::tr("Transformation matrix is not invertible."));
    }

    m_graphicState.setCurrentTransformationMatrix(transformMatrix);
    updateGraphicState();
}

template<>
PDFReal PDFPageContentProcessor::readOperand<PDFReal>(size_t index) const
{
    if (index < m_operands.size())
    {
        const PDFLexicalAnalyzer::Token& token = m_operands[index];

        switch (token.type)
        {
            case PDFLexicalAnalyzer::TokenType::Real:
            case PDFLexicalAnalyzer::TokenType::Integer:
                return token.data.value<PDFReal>();

            default:
                throw PDFRendererException(RenderErrorType::Error, PDFTranslationContext::tr("Can't read operand (real number) on index %1. Operand is of type '%2'.").arg(index + 1).arg(PDFLexicalAnalyzer::getStringFromOperandType(token.type)));
        }
    }
    else
    {
        throw PDFRendererException(RenderErrorType::Error, PDFTranslationContext::tr("Can't read operand (real number) on index %1. Only %2 operands provided.").arg(index + 1).arg(m_operands.size()));
    }
}

template<>
PDFInteger PDFPageContentProcessor::readOperand<PDFInteger>(size_t index) const
{
    if (index < m_operands.size())
    {
        const PDFLexicalAnalyzer::Token& token = m_operands[index];

        switch (token.type)
        {
            case PDFLexicalAnalyzer::TokenType::Integer:
                return token.data.value<PDFInteger>();

            default:
                throw PDFRendererException(RenderErrorType::Error, PDFTranslationContext::tr("Can't read operand (integer) on index %1. Operand is of type '%2'.").arg(index + 1).arg(PDFLexicalAnalyzer::getStringFromOperandType(token.type)));
        }
    }
    else
    {
        throw PDFRendererException(RenderErrorType::Error, PDFTranslationContext::tr("Can't read operand (integer) on index %1. Only %2 operands provided.").arg(index + 1).arg(m_operands.size()));
    }
}

template<>
PDFPageContentProcessor::PDFOperandName PDFPageContentProcessor::readOperand<PDFPageContentProcessor::PDFOperandName>(size_t index) const
{
    if (index < m_operands.size())
    {
        const PDFLexicalAnalyzer::Token& token = m_operands[index];

        switch (token.type)
        {
            case PDFLexicalAnalyzer::TokenType::Name:
                return PDFOperandName{ token.data.toByteArray() };

            default:
                throw PDFRendererException(RenderErrorType::Error, PDFTranslationContext::tr("Can't read operand (name) on index %1. Operand is of type '%2'.").arg(index + 1).arg(PDFLexicalAnalyzer::getStringFromOperandType(token.type)));
        }
    }
    else
    {
        throw PDFRendererException(RenderErrorType::Error, PDFTranslationContext::tr("Can't read operand (name) on index %1. Only %2 operands provided.").arg(index + 1).arg(m_operands.size()));
    }
}


template<>
PDFPageContentProcessor::PDFOperandString PDFPageContentProcessor::readOperand<PDFPageContentProcessor::PDFOperandString>(size_t index) const
{
    if (index < m_operands.size())
    {
        const PDFLexicalAnalyzer::Token& token = m_operands[index];

        switch (token.type)
        {
            case PDFLexicalAnalyzer::TokenType::String:
                return PDFOperandString{ token.data.toByteArray() };

            default:
                throw PDFRendererException(RenderErrorType::Error, PDFTranslationContext::tr("Can't read operand (string) on index %1. Operand is of type '%2'.").arg(index + 1).arg(PDFLexicalAnalyzer::getStringFromOperandType(token.type)));
        }
    }
    else
    {
        throw PDFRendererException(RenderErrorType::Error, PDFTranslationContext::tr("Can't read operand (string) on index %1. Only %2 operands provided.").arg(index + 1).arg(m_operands.size()));
    }
}

void PDFPageContentProcessor::operatorMoveCurrentPoint(PDFReal x, PDFReal y)
{
    m_currentPath.moveTo(x, y);;
}

void PDFPageContentProcessor::operatorLineTo(PDFReal x, PDFReal y)
{
    m_currentPath.lineTo(x, y);
}

void PDFPageContentProcessor::operatorBezier123To(PDFReal x1, PDFReal y1, PDFReal x2, PDFReal y2, PDFReal x3, PDFReal y3)
{
    m_currentPath.cubicTo(x1, y1, x2, y2, x3, y3);
}

void PDFPageContentProcessor::operatorBezier23To(PDFReal x2, PDFReal y2, PDFReal x3, PDFReal y3)
{
    QPointF currentPoint = getCurrentPoint();
    m_currentPath.cubicTo(currentPoint.x(), currentPoint.y(), x2, y2, x3, y3);
}

void PDFPageContentProcessor::operatorBezier13To(PDFReal x1, PDFReal y1, PDFReal x3, PDFReal y3)
{
    m_currentPath.cubicTo(x1, y1, x3, y3, x3, y3);
}

void PDFPageContentProcessor::operatorEndSubpath()
{
    m_currentPath.closeSubpath();
}

void PDFPageContentProcessor::operatorRectangle(PDFReal x, PDFReal y, PDFReal width, PDFReal height)
{
    const PDFReal xMin = qMin(x, x + width);
    const PDFReal xMax = qMax(x, x + width);
    const PDFReal yMin = qMin(y, y + height);
    const PDFReal yMax = qMax(y, y + height);
    const PDFReal correctedWidth = xMax - xMin;
    const PDFReal correctedHeight = yMax - yMin;

    m_currentPath.addRect(QRectF(xMin, yMin, correctedWidth, correctedHeight));
}

void PDFPageContentProcessor::operatorPathStroke()
{
    // Do not close the path
    if (!m_currentPath.isEmpty())
    {
        m_currentPath.setFillRule(Qt::WindingFill);
        processPathPainting(m_currentPath, true, false, false, Qt::WindingFill);
        m_currentPath = QPainterPath();
    }
}

void PDFPageContentProcessor::operatorPathCloseStroke()
{
    // Close the path
    if (!m_currentPath.isEmpty())
    {
        m_currentPath.closeSubpath();
        m_currentPath.setFillRule(Qt::WindingFill);
        processPathPainting(m_currentPath, true, false, false, Qt::WindingFill);
        m_currentPath = QPainterPath();
    }
}

void PDFPageContentProcessor::operatorPathFillWinding()
{
    if (!m_currentPath.isEmpty())
    {
        m_currentPath.setFillRule(Qt::WindingFill);
        processPathPainting(m_currentPath, false, true, false, Qt::WindingFill);
        m_currentPath = QPainterPath();
    }
}

void PDFPageContentProcessor::operatorPathFillEvenOdd()
{
    if (!m_currentPath.isEmpty())
    {
        m_currentPath.setFillRule(Qt::OddEvenFill);
        processPathPainting(m_currentPath, false, true, false, Qt::OddEvenFill);
        m_currentPath = QPainterPath();
    }
}

void PDFPageContentProcessor::operatorPathFillStrokeWinding()
{
    if (!m_currentPath.isEmpty())
    {
        m_currentPath.setFillRule(Qt::WindingFill);
        processPathPainting(m_currentPath, true, true, false, Qt::WindingFill);
        m_currentPath = QPainterPath();
    }
}

void PDFPageContentProcessor::operatorPathFillStrokeEvenOdd()
{
    if (!m_currentPath.isEmpty())
    {
        m_currentPath.setFillRule(Qt::OddEvenFill);
        processPathPainting(m_currentPath, true, true, false, Qt::OddEvenFill);
        m_currentPath = QPainterPath();
    }
}

void PDFPageContentProcessor::operatorPathCloseFillStrokeWinding()
{
    if (!m_currentPath.isEmpty())
    {
        m_currentPath.closeSubpath();
        m_currentPath.setFillRule(Qt::WindingFill);
        processPathPainting(m_currentPath, true, true, false, Qt::WindingFill);
        m_currentPath = QPainterPath();
    }
}

void PDFPageContentProcessor::operatorPathCloseFillStrokeEvenOdd()
{
    if (!m_currentPath.isEmpty())
    {
        m_currentPath.closeSubpath();
        m_currentPath.setFillRule(Qt::OddEvenFill);
        processPathPainting(m_currentPath, true, true, false, Qt::OddEvenFill);
        m_currentPath = QPainterPath();
    }
}

void PDFPageContentProcessor::operatorPathClear()
{
    m_currentPath = QPainterPath();
}

void PDFPageContentProcessor::operatorClipWinding()
{
    if (!m_currentPath.isEmpty())
    {
        m_currentPath.setFillRule(Qt::WindingFill);
        performClipping(m_currentPath, Qt::WindingFill);
    }
}

void PDFPageContentProcessor::operatorClipEvenOdd()
{
    if (!m_currentPath.isEmpty())
    {
        m_currentPath.setFillRule(Qt::OddEvenFill);
        performClipping(m_currentPath, Qt::OddEvenFill);
    }
}

void PDFPageContentProcessor::operatorType3FontSetOffset(PDFReal wx, PDFReal wy)
{
    performSetCharWidth(wx, wy);
}

void PDFPageContentProcessor::operatorType3FontSetOffsetAndBB(PDFReal wx, PDFReal wy, PDFReal llx, PDFReal lly, PDFReal urx, PDFReal ury)
{
    performSetCacheDevice(wx, wy, llx, lly, urx, ury);
}

void PDFPageContentProcessor::operatorColorSetStrokingColorSpace(PDFPageContentProcessor::PDFOperandName name)
{
    if (m_drawingUncoloredTilingPatternState)
    {
        reportWarningAboutColorOperatorsInUTP();
        return;
    }

    PDFColorSpacePointer colorSpace = PDFAbstractColorSpace::createColorSpace(m_colorSpaceDictionary, m_document, PDFObject::createName(name.name));
    if (colorSpace)
    {
        // We must also set default color (it can depend on the color space)
        m_graphicState.setStrokeColorSpace(colorSpace);
        m_graphicState.setStrokeColor(colorSpace->getDefaultColor(m_CMS, m_graphicState.getRenderingIntent(), this), colorSpace->getDefaultColorOriginal());
        updateGraphicState();
        checkStrokingColor();
    }
    else
    {
        throw PDFRendererException(RenderErrorType::Error, PDFTranslationContext::tr("Invalid color space."));
    }
}

void PDFPageContentProcessor::operatorColorSetFillingColorSpace(PDFOperandName name)
{
    if (m_drawingUncoloredTilingPatternState)
    {
        reportWarningAboutColorOperatorsInUTP();
        return;
    }

    PDFColorSpacePointer colorSpace = PDFAbstractColorSpace::createColorSpace(m_colorSpaceDictionary, m_document, PDFObject::createName(name.name));
    if (colorSpace)
    {
        // We must also set default color (it can depend on the color space)
        m_graphicState.setFillColorSpace(colorSpace);
        m_graphicState.setFillColor(colorSpace->getDefaultColor(m_CMS, m_graphicState.getRenderingIntent(), this), colorSpace->getDefaultColorOriginal());
        updateGraphicState();
        checkFillingColor();
    }
    else
    {
        throw PDFRendererException(RenderErrorType::Error, PDFTranslationContext::tr("Invalid color space."));
    }
}

void PDFPageContentProcessor::operatorColorSetStrokingColor()
{
    if (m_drawingUncoloredTilingPatternState)
    {
        reportWarningAboutColorOperatorsInUTP();
        return;
    }

    const PDFAbstractColorSpace* colorSpace = m_graphicState.getStrokeColorSpace();
    const size_t colorSpaceComponentCount = colorSpace->getColorComponentCount();
    const size_t operandCount = m_operands.size();

    if (operandCount == colorSpaceComponentCount)
    {
        PDFColor color;
        for (size_t i = 0; i < operandCount; ++i)
        {
            color.push_back(readOperand<PDFReal>(i));
        }
        m_graphicState.setStrokeColor(colorSpace->getColor(color, m_CMS, m_graphicState.getRenderingIntent(), this, true), color);
        updateGraphicState();
        checkStrokingColor();
    }
    else
    {
        throw PDFRendererException(RenderErrorType::Error, PDFTranslationContext::tr("Invalid color component count. Provided %1, required %2.").arg(operandCount).arg(colorSpaceComponentCount));
    }
}

void PDFPageContentProcessor::operatorColorSetStrokingColorN()
{
    if (m_drawingUncoloredTilingPatternState)
    {
        reportWarningAboutColorOperatorsInUTP();
        return;
    }

    // In our implementation, operator 'SC' can also set color using all color spaces
    // PDF reference 1.7 allows here Pattern, Separation, DeviceN and ICCBased color spaces here,
    // but default operator can use them (with exception of Pattern color space). For pattern color space,
    // we treat this differently.
    const PDFAbstractColorSpace* colorSpace = m_graphicState.getStrokeColorSpace();
    if (const PDFPatternColorSpace* patternColorSpace = colorSpace->asPatternColorSpace())
    {
        const size_t operandCount = m_operands.size();
        if (operandCount > 0)
        {
            PDFColorSpacePointer uncoloredColorSpace = patternColorSpace->getUncoloredPatternColorSpace();
            PDFColor uncoloredPatternColor;

            for (size_t i = 0; i < operandCount - 1; ++i)
            {
                uncoloredPatternColor.push_back(readOperand<PDFReal>(i));
            }

            PDFOperandName name = readOperand<PDFOperandName>(operandCount - 1);
            if (m_patternDictionary && m_patternDictionary->hasKey(name.name))
            {
                // Create the pattern
                PDFPatternPtr pattern = PDFPattern::createPattern(m_colorSpaceDictionary, m_document, m_patternDictionary->get(name.name), m_CMS, m_graphicState.getRenderingIntent(), this);
                m_graphicState.setStrokeColorSpace(PDFColorSpacePointer(new PDFPatternColorSpace(qMove(pattern), qMove(uncoloredColorSpace), qMove(uncoloredPatternColor))));
                updateGraphicState();
                return;
            }

            throw PDFRendererException(RenderErrorType::Error, PDFTranslationContext::tr("Invalid pattern for Pattern color space."));
        }
        else
        {
            throw PDFRendererException(RenderErrorType::Error, PDFTranslationContext::tr("Invalid pattern for Pattern color space."));
        }
    }
    else
    {
        operatorColorSetStrokingColor();
    }
}

void PDFPageContentProcessor::operatorColorSetFillingColor()
{
    if (m_drawingUncoloredTilingPatternState)
    {
        reportWarningAboutColorOperatorsInUTP();
        return;
    }

    const PDFAbstractColorSpace* colorSpace = m_graphicState.getFillColorSpace();
    const size_t colorSpaceComponentCount = colorSpace->getColorComponentCount();
    const size_t operandCount = m_operands.size();

    if (operandCount == colorSpaceComponentCount)
    {
        PDFColor color;
        for (size_t i = 0; i < operandCount; ++i)
        {
            color.push_back(readOperand<PDFReal>(i));
        }
        m_graphicState.setFillColor(colorSpace->getColor(color, m_CMS, m_graphicState.getRenderingIntent(), this, true), color);
        updateGraphicState();
        checkFillingColor();
    }
    else
    {
        throw PDFRendererException(RenderErrorType::Error, PDFTranslationContext::tr("Invalid color component count. Provided %1, required %2.").arg(operandCount).arg(colorSpaceComponentCount));
    }
}

void PDFPageContentProcessor::operatorColorSetFillingColorN()
{
    if (m_drawingUncoloredTilingPatternState)
    {
        reportWarningAboutColorOperatorsInUTP();
        return;
    }

    // In our implementation, operator 'sc' can also set color using all color spaces
    // PDF reference 1.7 allows here Pattern, Separation, DeviceN and ICCBased color spaces here,
    // but default operator can use them (with exception of Pattern color space). For pattern color space,
    // we treat this differently.
    const PDFAbstractColorSpace* colorSpace = m_graphicState.getFillColorSpace();
    if (const PDFPatternColorSpace* patternColorSpace = colorSpace->asPatternColorSpace())
    {
        const size_t operandCount = m_operands.size();
        if (operandCount > 0)
        {
            PDFColorSpacePointer uncoloredColorSpace = patternColorSpace->getUncoloredPatternColorSpace();
            PDFColor uncoloredPatternColor;

            for (size_t i = 0; i < operandCount - 1; ++i)
            {
                uncoloredPatternColor.push_back(readOperand<PDFReal>(i));
            }

            PDFOperandName name = readOperand<PDFOperandName>(operandCount - 1);
            if (m_patternDictionary && m_patternDictionary->hasKey(name.name))
            {
                // Create the pattern
                PDFPatternPtr pattern = PDFPattern::createPattern(m_colorSpaceDictionary, m_document, m_patternDictionary->get(name.name), m_CMS, m_graphicState.getRenderingIntent(), this);
                m_graphicState.setFillColorSpace(QSharedPointer<PDFAbstractColorSpace>(new PDFPatternColorSpace(qMove(pattern), qMove(uncoloredColorSpace), qMove(uncoloredPatternColor))));
                updateGraphicState();
                return;
            }

            throw PDFRendererException(RenderErrorType::Error, PDFTranslationContext::tr("Invalid pattern for Pattern color space."));
        }
        else
        {
            throw PDFRendererException(RenderErrorType::Error, PDFTranslationContext::tr("Invalid pattern for Pattern color space."));
        }
    }
    else
    {
        operatorColorSetFillingColor();
    }
}

void PDFPageContentProcessor::operatorColorSetDeviceGrayStroking(PDFReal gray)
{
    if (m_drawingUncoloredTilingPatternState)
    {
        reportWarningAboutColorOperatorsInUTP();
        return;
    }

    m_graphicState.setStrokeColorSpace(m_deviceGrayColorSpace);
    m_graphicState.setStrokeColor(getColorFromColorSpace(m_graphicState.getStrokeColorSpace(), gray), PDFColor(PDFColorComponent(gray)));
    updateGraphicState();
    checkStrokingColor();
}

void PDFPageContentProcessor::operatorColorSetDeviceGrayFilling(PDFReal gray)
{
    if (m_drawingUncoloredTilingPatternState)
    {
        reportWarningAboutColorOperatorsInUTP();
        return;
    }

    m_graphicState.setFillColorSpace(m_deviceGrayColorSpace);
    m_graphicState.setFillColor(getColorFromColorSpace(m_graphicState.getFillColorSpace(), gray), PDFColor(PDFColorComponent(gray)));
    updateGraphicState();
    checkFillingColor();
}

void PDFPageContentProcessor::operatorColorSetDeviceRGBStroking(PDFReal r, PDFReal g, PDFReal b)
{
    if (m_drawingUncoloredTilingPatternState)
    {
        reportWarningAboutColorOperatorsInUTP();
        return;
    }

    m_graphicState.setStrokeColorSpace(m_deviceRGBColorSpace);
    m_graphicState.setStrokeColor(getColorFromColorSpace(m_graphicState.getStrokeColorSpace(), r, g, b), PDFColor(PDFColorComponent(r), PDFColorComponent(g), PDFColorComponent(b)));
    updateGraphicState();
    checkStrokingColor();
}

void PDFPageContentProcessor::operatorColorSetDeviceRGBFilling(PDFReal r, PDFReal g, PDFReal b)
{
    if (m_drawingUncoloredTilingPatternState)
    {
        reportWarningAboutColorOperatorsInUTP();
        return;
    }

    m_graphicState.setFillColorSpace(m_deviceRGBColorSpace);
    m_graphicState.setFillColor(getColorFromColorSpace(m_graphicState.getFillColorSpace(), r, g, b), PDFColor(PDFColorComponent(r), PDFColorComponent(g), PDFColorComponent(b)));
    updateGraphicState();
    checkFillingColor();
}

void PDFPageContentProcessor::operatorColorSetDeviceCMYKStroking(PDFReal c, PDFReal m, PDFReal y, PDFReal k)
{
    if (m_drawingUncoloredTilingPatternState)
    {
        reportWarningAboutColorOperatorsInUTP();
        return;
    }

    m_graphicState.setStrokeColorSpace(m_deviceCMYKColorSpace);
    m_graphicState.setStrokeColor(getColorFromColorSpace(m_graphicState.getStrokeColorSpace(), c, m, y, k), PDFColor(PDFColorComponent(c), PDFColorComponent(m), PDFColorComponent(y), PDFColorComponent(k)));
    updateGraphicState();
    checkStrokingColor();
}

void PDFPageContentProcessor::operatorColorSetDeviceCMYKFilling(PDFReal c, PDFReal m, PDFReal y, PDFReal k)
{
    if (m_drawingUncoloredTilingPatternState)
    {
        reportWarningAboutColorOperatorsInUTP();
        return;
    }

    m_graphicState.setFillColorSpace(m_deviceCMYKColorSpace);
    m_graphicState.setFillColor(getColorFromColorSpace(m_graphicState.getFillColorSpace(), c, m, y, k), PDFColor(PDFColorComponent(c), PDFColorComponent(m), PDFColorComponent(y), PDFColorComponent(k)));
    updateGraphicState();
    checkFillingColor();
}

void PDFPageContentProcessor::operatorTextBegin()
{
    performTextBegin(ProcessOrder::BeforeOperation);
    m_graphicState.setTextMatrix(QTransform());
    m_graphicState.setTextLineMatrix(QTransform());
    updateGraphicState();

    ++m_textBeginEndState;

    if (m_textBeginEndState > 1)
    {
        throw PDFRendererException(RenderErrorType::Error, PDFTranslationContext::tr("Text object already started."));
    }

    performTextBegin(ProcessOrder::AfterOperation);
}

void PDFPageContentProcessor::operatorTextEnd()
{
    if (--m_textBeginEndState < 0)
    {
        throw PDFRendererException(RenderErrorType::Error, PDFTranslationContext::tr("Text object ended more than once."));
    }

    performTextEnd(ProcessOrder::BeforeOperation);
    if (!m_textClippingPath.isEmpty())
    {
        QPainterPath clippingPath = m_graphicState.getCurrentTransformationMatrix().inverted().map(m_textClippingPath);
        performClipping(clippingPath, clippingPath.fillRule());
        m_textClippingPath = QPainterPath();
    }
    performTextEnd(ProcessOrder::AfterOperation);
}

void PDFPageContentProcessor::operatorTextSetCharacterSpacing(PDFReal charSpacing)
{
    m_graphicState.setTextCharacterSpacing(charSpacing);
    updateGraphicState();
}

void PDFPageContentProcessor::operatorTextSetWordSpacing(PDFReal wordSpacing)
{
    m_graphicState.setTextWordSpacing(wordSpacing);
    updateGraphicState();
}

void PDFPageContentProcessor::operatorTextSetHorizontalScale(PDFReal horizontalScaling)
{
    // We disable horizontal scaling to less than 1%
    if (horizontalScaling >= 0.0 && horizontalScaling < 1.0)
    {
        horizontalScaling = 1.0;
    }
    if (horizontalScaling < 0.0 && horizontalScaling > -1.0)
    {
        horizontalScaling = -1.0;
    }

    m_graphicState.setTextHorizontalScaling(horizontalScaling);
    updateGraphicState();
}

void PDFPageContentProcessor::operatorTextSetLeading(PDFReal leading)
{
    m_graphicState.setTextLeading(leading);
    updateGraphicState();
}

void PDFPageContentProcessor::operatorTextSetFontAndFontSize(PDFOperandName fontName, PDFReal fontSize)
{
    if (m_fontDictionary)
    {
        if (m_fontDictionary->hasKey(fontName.name))
        {
            try
            {
                PDFFontPointer font = m_fontCache->getFont(m_fontDictionary->get(fontName.name));

                m_graphicState.setTextFont(qMove(font));
                m_graphicState.setTextFontSize(fontSize);
                updateGraphicState();
            }
            catch (const PDFException&)
            {
                m_graphicState.setTextFont(nullptr);
                m_graphicState.setTextFontSize(fontSize);
                updateGraphicState();
                throw;
            }
        }
        else
        {
            throw PDFRendererException(RenderErrorType::Error, PDFTranslationContext::tr("Font '%1' not found in font dictionary.").arg(QString::fromLatin1(fontName.name)));
        }
    }
    else
    {
        throw PDFRendererException(RenderErrorType::Error, PDFTranslationContext::tr("Invalid font dictionary."));
    }
}

void PDFPageContentProcessor::operatorTextSetRenderMode(PDFInteger mode)
{
    mode = qBound<PDFInteger>(PDFInteger(0), mode, PDFInteger(7));
    m_graphicState.setTextRenderingMode(static_cast<TextRenderingMode>(mode));
    updateGraphicState();
}

void PDFPageContentProcessor::operatorTextSetRise(PDFReal rise)
{
    m_graphicState.setTextRise(rise);
    updateGraphicState();
}

void PDFPageContentProcessor::operatorTextMoveByOffset(PDFReal t_x, PDFReal t_y)
{
    const QTransform& textLineMatrix = m_graphicState.getTextLineMatrix();
    QTransform transformedMatrix = QTransform(1, 0, 0, 1, t_x, t_y) * textLineMatrix;

    m_graphicState.setTextMatrix(transformedMatrix);
    m_graphicState.setTextLineMatrix(transformedMatrix);
    updateGraphicState();
}

void PDFPageContentProcessor::operatorTextSetLeadingAndMoveByOffset(PDFReal t_x, PDFReal t_y)
{
    // Update of graphic state is
    m_graphicState.setTextLeading(-t_y);
    operatorTextMoveByOffset(t_x, t_y);
}

void PDFPageContentProcessor::operatorTextSetMatrix(PDFReal a, PDFReal b, PDFReal c, PDFReal d, PDFReal e, PDFReal f)
{
    // We will comment following equation:
    //  Adobe PDF Reference 1.7 says, that we have this transformation using coefficient a, b, c, d, e and f:
    //                             [ a, b, 0 ]
    //  [x', y', 1] = [ x, y, 1] * [ c, d, 0 ]
    //                             [ e, f, 1 ]
    // If we transpose this equation (we want this, because Qt uses transposed matrices (QTransform).
    // So, we will get following result:
    //
    // [ x' ]   [ a, c, e]    [ x ]
    // [ y' ] = [ b, d, f] *  [ y ]
    // [ 1  ]   [ 0, 0, 1]    [ 1 ]
    //
    // So, it is obvious, than we will have following coefficients:
    //  m_11 = a, m_21 = c, dx = e
    //  m_12 = b, m_22 = d, dy = f
    //
    // We must also check, that matrix is invertible. If it is not, then we will throw exception
    // to avoid errors later (for some operations, we assume matrix is invertible).

    QTransform matrix(a, b, c, d, e, f);

    m_graphicState.setTextMatrix(matrix);
    m_graphicState.setTextLineMatrix(matrix);
    updateGraphicState();
}

void PDFPageContentProcessor::operatorTextMoveByLeading()
{
    operatorTextMoveByOffset(0.0, -m_graphicState.getTextLeading());
}

void PDFPageContentProcessor::operatorTextShowTextString(PDFOperandString text)
{
    if (m_graphicState.getTextFont())
    {
        // Get the realized font
        const PDFRealizedFontPointer& realizedFont = getRealizedFont();
        if (!realizedFont)
        {
            throw PDFRendererException(RenderErrorType::Error, PDFTranslationContext::tr("Invalid font, text can't be printed."));
        }

        TextSequence textSequence;

        // We use simple heuristic to ensure reallocation doesn't occur too often
        textSequence.items.reserve(m_operands.size());
        realizedFont->fillTextSequence(text.string, textSequence, this);
        drawText(textSequence);
    }
    else
    {
        throw PDFRendererException(RenderErrorType::Error, PDFTranslationContext::tr("Invalid font, text can't be printed."));
    }
}

void PDFPageContentProcessor::operatorTextShowTextIndividualSpacing()
{
    // Operand stack must be of this form [ ... text, number, text, number, number, text ... ]. We check it.

    if (m_operands.size() < 2)
    {
        throw PDFRendererException(RenderErrorType::Error, PDFTranslationContext::tr("Invalid parameters of text operator with individual character spacing."));
    }

    // Now, we have at least 2 arguments. Check we have an array
    if (m_operands[0].type != PDFLexicalAnalyzer::TokenType::ArrayStart ||
        m_operands[m_operands.size() - 1].type != PDFLexicalAnalyzer::TokenType::ArrayEnd)
    {
        throw PDFRendererException(RenderErrorType::Error, PDFTranslationContext::tr("Invalid line dash pattern."));
    }

    if (m_graphicState.getTextFont())
    {
        TextSequence textSequence;

        // We use simple heuristic to ensure reallocation doesn't occur too often
        textSequence.items.reserve(m_operands.size() * 4);

        // Get the realized font
        const PDFRealizedFontPointer& realizedFont = getRealizedFont();
        if (!realizedFont)
        {
            throw PDFRendererException(RenderErrorType::Error, PDFTranslationContext::tr("Invalid font, text can't be printed."));
        }

        for (size_t i = 1, lastIndex = m_operands.size() - 1; i < lastIndex; ++i)
        {
            switch (m_operands[i].type)
            {
                case PDFLexicalAnalyzer::TokenType::Integer:
                {
                    textSequence.items.push_back(TextSequenceItem(m_operands[i].data.value<PDFInteger>()));
                    break;
                }

                case PDFLexicalAnalyzer::TokenType::Real:
                {
                    textSequence.items.push_back(TextSequenceItem(m_operands[i].data.value<PDFReal>()));
                    break;
                }

                case PDFLexicalAnalyzer::TokenType::String:
                {
                    realizedFont->fillTextSequence(m_operands[i].data.toByteArray(), textSequence, this);
                    break;
                }

                default:
                {
                    // Error - we have operand of different type
                    throw PDFRendererException(RenderErrorType::Error, PDFTranslationContext::tr("Invalid operand of text show operator."));
                }
            }
        }

        drawText(textSequence);
    }
    else
    {
        throw PDFRendererException(RenderErrorType::Error, PDFTranslationContext::tr("Invalid font, text can't be printed."));
    }
}

void PDFPageContentProcessor::operatorTextNextLineShowText(PDFOperandString text)
{
    operatorTextMoveByLeading();
    operatorTextShowTextString(qMove(text));
}

void PDFPageContentProcessor::operatorTextSetSpacingAndShowText(PDFReal t_w, PDFReal t_c, PDFOperandString text)
{
    m_graphicState.setTextWordSpacing(t_w);
    m_graphicState.setTextCharacterSpacing(t_c);
    updateGraphicState();

    operatorTextNextLineShowText(qMove(text));
}

void PDFPageContentProcessor::operatorShadingPaintShape(PDFPageContentProcessor::PDFOperandName name)
{
    if (isContentKindSuppressed(ContentKind::Shading))
    {
        // Shadings are suppressed
        return;
    }

    QTransform matrix = getCurrentWorldMatrix();
    PDFPageContentProcessorStateGuard guard(this);
    PDFTemporaryValueChange guard2(&m_patternBaseMatrix, matrix);

    if (!m_shadingDictionary)
    {
        throw PDFRendererException(RenderErrorType::Error, PDFTranslationContext::tr("Shading '%1' not found.").arg(QString::fromLatin1(name.name)));
    }

    PDFPatternPtr pattern = PDFPattern::createShadingPattern(m_colorSpaceDictionary, m_document, m_shadingDictionary->get(name.name), QTransform(), PDFObject(), m_CMS, m_graphicState.getRenderingIntent(), this, true);

    // We will do a trick: we will set current fill color space, and then paint
    // bounding rectangle in the color pattern.
    m_graphicState.setFillColorSpace(PDFColorSpacePointer(new PDFPatternColorSpace(qMove(pattern), nullptr, PDFColor())));
    updateGraphicState();

    Q_ASSERT(matrix.isInvertible());
    QTransform inverted = matrix.inverted();

    QPainterPath deviceBoundingRectPath;
    deviceBoundingRectPath.addRect(m_pageBoundingRectDeviceSpace);
    QPainterPath boundingRectPath = inverted.map(deviceBoundingRectPath);

    processPathPainting(boundingRectPath, false, true, false, boundingRectPath.fillRule());
}

void PDFPageContentProcessor::paintXObjectImage(const PDFStream* stream)
{
    if (isContentKindSuppressed(ContentKind::Images))
    {
        // Images are suppressed
        return;
    }

    PDFColorSpacePointer colorSpace;

    const PDFDictionary* streamDictionary = stream->getDictionary();
    if (streamDictionary->hasKey("ColorSpace"))
    {
        const PDFObject& colorSpaceObject = m_document->getObject(streamDictionary->get("ColorSpace"));
        if (colorSpaceObject.isName() || colorSpaceObject.isArray())
        {
            colorSpace = PDFAbstractColorSpace::createColorSpace(m_colorSpaceDictionary, m_document, colorSpaceObject);
        }
        else if (!colorSpaceObject.isNull())
        {
            throw PDFRendererException(RenderErrorType::Error, PDFTranslationContext::tr("Invalid color space of the image."));
        }
    }

    PDFImage pdfImage = PDFImage::createImage(m_document, stream, qMove(colorSpace), false, m_graphicState.getRenderingIntent(), this);

    if (!performOriginalImagePainting(pdfImage))
    {
        QImage image = pdfImage.getImage(m_CMS, this, m_operationControl);

        if (!isProcessingCancelled())
        {
            if (image.format() == QImage::Format_Alpha8)
            {
                QSize size = image.size();
                QImage unmaskedImage(size, QImage::Format_ARGB32_Premultiplied);
                unmaskedImage.fill(m_graphicState.getFillColor());
                unmaskedImage.setAlphaChannel(image);
                image = qMove(unmaskedImage);
            }

            if (!image.isNull())
            {
                performImagePainting(image);
            }
            else
            {
                throw PDFRendererException(RenderErrorType::Error, PDFTranslationContext::tr("Can't decode the image."));
            }
        }
    }
}

void PDFPageContentProcessor::reportWarningAboutColorOperatorsInUTP()
{
    reportRenderErrorOnce(RenderErrorType::Warning, PDFTranslationContext::tr("Color operators are not allowed in uncolored tilling pattern."));
}

void PDFPageContentProcessor::processForm(const PDFStream* stream)
{
    PDFDocumentDataLoaderDecorator loader(getDocument());
    const PDFDictionary* streamDictionary = stream->getDictionary();

    // Read the bounding rectangle, if it is present
    QRectF boundingBox = loader.readRectangle(streamDictionary->get("BBox"), QRectF());

    // Read the transformation matrix, if it is present
    QTransform transformationMatrix = loader.readMatrixFromDictionary(streamDictionary, "Matrix", QTransform());

    // Read the dictionary content
    QByteArray content = m_document->getDecodedStream(stream);

    // Read resources
    PDFObject resources = m_document->getObject(streamDictionary->get("Resources"));

    // Transparency group
    PDFObject transparencyGroup = m_document->getObject(streamDictionary->get("Group"));

    // Form structural parent key
    const PDFInteger formStructuralParentKey = loader.readIntegerFromDictionary(streamDictionary, "StructParent", m_structuralParentKey);

    processForm(transformationMatrix, boundingBox, resources, transparencyGroup, content, formStructuralParentKey);
}

void PDFPageContentProcessor::operatorPaintXObject(PDFOperandName name)
{
    // We want to have empty operands, when we are invoking forms
    m_operands.clear();

    if (m_xobjectDictionary)
    {
        const PDFObject& object = m_document->getObject(m_xobjectDictionary->get(name.name));
        if (object.isStream())
        {
            const PDFStream* stream = object.getStream();
            const PDFDictionary* streamDictionary = stream->getDictionary();

            // According to the specification, XObjects are skipped entirely, as no operator was invoked.
            if (streamDictionary->hasKey("OC"))
            {
                const PDFObject& optionalContentObject = streamDictionary->get("OC");
                if (optionalContentObject.isReference())
                {
                    if (isContentSuppressedByOC(optionalContentObject.getReference()))
                    {
                        return;
                    }
                }
                else
                {
                    throw PDFRendererException(RenderErrorType::Error, PDFTranslationContext::tr("Reference to optional content expected."));
                }
            }

            PDFDocumentDataLoaderDecorator loader(m_document);
            QByteArray subtype = loader.readNameFromDictionary(streamDictionary, "Subtype");
            if (subtype == "Image")
            {
                paintXObjectImage(stream);
            }
            else if (subtype == "Form")
            {
                PDFInteger formType = loader.readIntegerFromDictionary(streamDictionary, "FormType", 1);
                if (formType != 1)
                {
                    throw PDFRendererException(RenderErrorType::Error, PDFTranslationContext::tr("Form of type %1 not supported.").arg(formType));
                }

                processForm(stream);
            }
            else
            {
                throw PDFRendererException(RenderErrorType::Error, PDFTranslationContext::tr("Unknown XObject type '%1'.").arg(QString::fromLatin1(subtype)));
            }
        }
        else
        {
            throw PDFRendererException(RenderErrorType::Error, PDFTranslationContext::tr("Invalid format of XObject. Dictionary expected."));
        }
    }
    else
    {
        throw PDFRendererException(RenderErrorType::Error, PDFTranslationContext::tr("XObject resource dictionary not found."));
    }
}

void PDFPageContentProcessor::operatorMarkedContentPoint(PDFOperandName name)
{
    performMarkedContentPoint(name.name, PDFObject());
}

void PDFPageContentProcessor::operatorMarkedContentPointWithProperties(PDFOperandName name, PDFObject properties)
{
    performMarkedContentPoint(name.name, properties);
}

void PDFPageContentProcessor::operatorMarkedContentBegin(PDFOperandName name)
{
    operatorMarkedContentBeginWithProperties(qMove(name), PDFObject());
}

void PDFPageContentProcessor::operatorMarkedContentBeginWithProperties(PDFOperandName name, PDFObject properties)
{
    // Handle the optional content
    if (name.name == "OC")
    {
        PDFObjectReference ocg;
        if (m_propertiesDictionary && properties.isName())
        {
            const PDFObject& ocgObject = m_propertiesDictionary->get(properties.getString());
            if (ocgObject.isReference())
            {
                ocg = ocgObject.getReference();
            }
        }

        m_markedContentStack.emplace_back(name.name, MarkedContentKind::OptionalContent, isContentSuppressedByOC(ocg));
    }
    else
    {
        m_markedContentStack.emplace_back(name.name, MarkedContentKind::Other, false);
    }

    performMarkedContentBegin(name.name, properties);
}

void PDFPageContentProcessor::operatorMarkedContentEnd()
{
    if (m_markedContentStack.empty())
    {
        throw PDFRendererException(RenderErrorType::Error, PDFTranslationContext::tr("Mismatched begin/end of marked content."));
    }

    m_markedContentStack.pop_back();
    performMarkedContentEnd();
}

void PDFPageContentProcessor::operatorCompatibilityBegin()
{
    ++m_compatibilityBeginEndState;
}

void PDFPageContentProcessor::operatorCompatibilityEnd()
{
    if (--m_compatibilityBeginEndState < 0)
    {
        throw PDFRendererException(RenderErrorType::Error, PDFTranslationContext::tr("Compatibility operator begin/end mismatch."));
    }
}

void PDFPageContentProcessor::drawText(const TextSequence& textSequence)
{
    if (textSequence.items.empty())
    {
        // Do not display empty text
        return;
    }

    const PDFRealizedFontPointer& font = getRealizedFont();
    if (font)
    {
        const bool isType3Font = m_graphicState.getTextFont()->getFontType() == FontType::Type3;
        const PDFReal fontSize = m_graphicState.getTextFontSize();
        const PDFReal horizontalScaling = m_graphicState.getTextHorizontalScaling() * 0.01; // Horizontal scaling is in percents
        const PDFReal characterSpacing = m_graphicState.getTextCharacterSpacing();
        const PDFReal wordSpacing = m_graphicState.getTextWordSpacing();
        const PDFReal textRise = m_graphicState.getTextRise();
        const TextRenderingMode textRenderingMode = m_graphicState.getTextRenderingMode();
        const bool fill = isTextRenderingModeFilled(textRenderingMode);
        const bool stroke = isTextRenderingModeStroked(textRenderingMode);
        const bool clipped = isTextRenderingModeClipped(textRenderingMode);

        // Detect horizontal writing system
        const bool isHorizontalWritingSystem = font->isHorizontalWritingSystem();

        // Calculate text rendering matrix
        const PDFReal fontFactor = (fontSize < 0.0) ? -1.0 : 1.0;
        QTransform adjustMatrix(horizontalScaling * fontFactor, 0.0, 0.0, fontFactor, 0.0, textRise);
        QTransform textMatrix = m_graphicState.getTextMatrix();

        if (!isType3Font)
        {
            for (const TextSequenceItem& item : textSequence.items)
            {
                PDFReal displacementX = 0.0;
                PDFReal displacementY = 0.0;

                if (item.isCharacter())
                {
                    QChar character = item.character;
                    QPointF advance = isHorizontalWritingSystem ? QPointF(item.advance, 0) : QPointF(0, item.advance);

                    // First, compute the advance
                    const PDFReal additionalAdvance = (character == QChar(QChar::Space)) ? wordSpacing + characterSpacing : characterSpacing;
                    if (isHorizontalWritingSystem)
                    {
                        advance.rx() += additionalAdvance;
                    }
                    else
                    {
                        advance.ry() += additionalAdvance;
                    }
                    advance.rx() *= horizontalScaling * fontFactor;

                    // Then get the glyph path and paint it
                    if (item.glyph)
                    {
                        const QPainterPath& glyphPath = *item.glyph;

                        QTransform textRenderingMatrix = adjustMatrix * textMatrix;
                        QTransform toDeviceSpaceTransform = textRenderingMatrix * m_graphicState.getCurrentTransformationMatrix();

                        if (!glyphPath.isEmpty())
                        {
                            QPainterPath transformedGlyph = textRenderingMatrix.map(glyphPath);
                            processPathPainting(transformedGlyph, stroke, fill, true, transformedGlyph.fillRule());

                            if (clipped)
                            {
                                // Clipping is enabled, we must transform to the device coordinates
                                m_textClippingPath = m_textClippingPath.united(toDeviceSpaceTransform.map(glyphPath));
                            }
                        }

                        if (!item.character.isNull())
                        {
                            // Output character
                            PDFTextCharacterInfo info;
                            info.character = item.character;
                            info.isVerticalWritingSystem = !isHorizontalWritingSystem;
                            info.advance = item.advance;
                            info.fontSize = fontSize;
                            info.outline = glyphPath;
                            info.matrix = toDeviceSpaceTransform;
                            performOutputCharacter(info);
                        }
                    }

                    displacementX = advance.x();
                    displacementY = advance.y();
                }
                else if (item.isAdvance())
                {
                    if (isHorizontalWritingSystem)
                    {
                        displacementX = -item.advance * 0.001 * fontSize * horizontalScaling;
                    }
                    else
                    {
                        displacementY = -item.advance * 0.001 * fontSize;
                    }
                }

                textMatrix.translate(displacementX, displacementY);
            }
        }
        else
        {
            // Type 3 Font

            Q_ASSERT(dynamic_cast<const PDFType3Font*>(m_graphicState.getTextFont().get()));
            const PDFType3Font* parentFont = static_cast<const PDFType3Font*>(m_graphicState.getTextFont().get());

            QTransform fontMatrix = parentFont->getFontMatrix();
            if (!fontMatrix.isInvertible())
            {
                throw PDFRendererException(RenderErrorType::Error, PDFTranslationContext::tr("Type 3 font matrix is not invertible."));
            }

            PDFPageContentProcessorStateGuard guard(this);

            PDFObject resources = parentFont->getResources();
            if (!resources.isNull())
            {
                initDictionaries(resources);
            }

            QTransform scaleMatrix(fontSize, 0.0, 0.0, fontSize, 0.0, 0.0);
            adjustMatrix = scaleMatrix * adjustMatrix;
            QTransform fontAdjustedMatrix = fontMatrix * adjustMatrix;

            for (const TextSequenceItem& item : textSequence.items)
            {
                // First, compute horizontal advance

                qreal displacementX = 0.0;
                if (!item.isContentStream())
                {
                    displacementX = -item.advance * 0.001 * fontSize * horizontalScaling;
                }
                else if (item.advance != 0.0)
                {
                    qreal ry = 0.0;
                    fontAdjustedMatrix.map(item.advance, 0.0, &displacementX, &ry);
                }

                if (item.characterContentStream && (fill || stroke))
                {
                    PDFPageContentProcessorStateGuard guard2(this);

                    // We must clear operands, because we are processing a new content stream
                    m_operands.clear();

                    QTransform worldMatrix = fontAdjustedMatrix * textMatrix * m_graphicState.getCurrentTransformationMatrix();
                    m_graphicState.setCurrentTransformationMatrix(worldMatrix);
                    updateGraphicState();

                    processContent(*item.characterContentStream);

                    if (!item.character.isNull())
                    {
                        // Output character
                        PDFTextCharacterInfo info;
                        info.character = item.character;
                        info.isVerticalWritingSystem = !isHorizontalWritingSystem;
                        info.advance = item.advance;
                        info.fontSize = fontSize;
                        info.matrix = worldMatrix;
                        performOutputCharacter(info);
                    }
                }

                textMatrix.translate(displacementX, 0.0);
            }
        }

        m_graphicState.setTextMatrix(textMatrix);
        updateGraphicState();
    }
    else
    {
        throw PDFRendererException(RenderErrorType::Error, PDFTranslationContext::tr("Invalid font, text can't be printed."));
    }
}

PDFRealizedFontPointer PDFPageContentProcessor::getRealizedFontImpl()
{
    if (m_graphicState.getTextFont())
    {
        return m_fontCache->getRealizedFont(m_graphicState.getTextFont(), m_graphicState.getTextFontSize(), this);
    }

    return PDFRealizedFontPointer();
}

void PDFPageContentProcessor::checkStrokingColor()
{
    if (!m_graphicState.getStrokeColor().isValid())
    {
        throw PDFRendererException(RenderErrorType::Error, PDFTranslationContext::tr("Invalid stroking color."));
    }
}

void PDFPageContentProcessor::checkFillingColor()
{
    if (!m_graphicState.getFillColor().isValid())
    {
        throw PDFRendererException(RenderErrorType::Error, PDFTranslationContext::tr("Invalid filling color."));
    }
}

PDFObject PDFPageContentProcessor::readObjectFromOperandStack(size_t startPosition) const
{
    auto tokenFetcher = [this, &startPosition]()
    {
        if (startPosition < m_operands.size())
        {
            return m_operands[startPosition++];
        }
        return PDFLexicalAnalyzer::Token();
    };

    PDFParser parser(tokenFetcher);
    return parser.getObject();
}

bool PDFPageContentProcessor::isContentSuppressedByOC(PDFObjectReference ocgOrOcmd)
{
    if (!m_optionalContentActivity)
    {
        // Optional content activity control is suppressed, treat all content as not suppressed
        return false;
    }

    if (m_optionalContentActivity->getProperties()->hasOptionalContentGroup(ocgOrOcmd))
    {
        // Simplest case - we have single optional content group
        return m_optionalContentActivity->getState(ocgOrOcmd) == OCState::OFF;
    }

    PDFOptionalContentMembershipObject ocmd;
    try
    {
        ocmd = PDFOptionalContentMembershipObject::create(m_document, PDFObject::createReference(ocgOrOcmd));
    }
    catch (const PDFException &e)
    {
        m_errorList.push_back(PDFRenderError(RenderErrorType::Error, e.getMessage()));
    }

    if (ocmd.isValid())
    {
        return ocmd.evaluate(m_optionalContentActivity) == OCState::OFF;
    }

    return false;
}

PDFPageContentProcessor::PDFPageContentProcessorState::PDFPageContentProcessorState() :
    m_currentTransformationMatrix(),
    m_strokeColorSpace(),
    m_fillColorSpace(),
    m_strokeColor(Qt::black),
    m_strokeColorOriginal(),
    m_fillColor(Qt::black),
    m_fillColorOriginal(),
    m_lineWidth(1.0),
    m_lineCapStyle(Qt::FlatCap),
    m_lineJoinStyle(Qt::MiterJoin),
    m_mitterLimit(10.0),
    m_renderingIntentName(),
    m_flatness(1.0),
    m_smoothness(0.01),
    m_textCharacterSpacing(0.0),
    m_textWordSpacing(0.0),
    m_textHorizontalScaling(100.0),
    m_textLeading(0.0),
    m_textFontSize(0.0),
    m_textRenderingMode(TextRenderingMode::Fill),
    m_textRise(0.0),
    m_textKnockout(true),
    m_alphaStroking(1.0),
    m_alphaFilling(1.0),
    m_blendMode(BlendMode::Normal),
    m_renderingIntent(RenderingIntent::Perceptual),
    m_overprintMode(),
    m_alphaIsShape(false),
    m_strokeAdjustment(false),
    m_softMask(nullptr),
    m_blackPointCompensationMode(BlackPointCompensationMode::Default),
    m_stateFlags(StateUnchanged)
{
    m_fillColorSpace.reset(new PDFDeviceGrayColorSpace);
    m_strokeColorSpace = m_fillColorSpace;

    m_fillColorOriginal = m_fillColorSpace->getDefaultColorOriginal();
    m_strokeColorOriginal = m_fillColorOriginal;
}

PDFPageContentProcessor::PDFPageContentProcessorState::~PDFPageContentProcessorState()
{

}

PDFPageContentProcessor::PDFPageContentProcessorState& PDFPageContentProcessor::PDFPageContentProcessorState::operator=(const PDFPageContentProcessor::PDFPageContentProcessorState& other)
{
    setCurrentTransformationMatrix(other.getCurrentTransformationMatrix());
    setStrokeColorSpace(other.m_strokeColorSpace);
    setFillColorSpace(other.m_fillColorSpace);
    setStrokeColor(other.getStrokeColor(), other.getStrokeColorOriginal());
    setFillColor(other.getFillColor(), other.getFillColorOriginal());
    setLineWidth(other.getLineWidth());
    setLineCapStyle(other.getLineCapStyle());
    setLineJoinStyle(other.getLineJoinStyle());
    setMitterLimit(other.getMitterLimit());
    setLineDashPattern(other.getLineDashPattern());
    setRenderingIntentName(other.getRenderingIntentName());
    setFlatness(other.getFlatness());
    setSmoothness(other.getSmoothness());
    setTextCharacterSpacing(other.getTextCharacterSpacing());
    setTextWordSpacing(other.getTextWordSpacing());
    setTextHorizontalScaling(other.getTextHorizontalScaling());
    setTextLeading(other.getTextLeading());
    setTextFont(other.getTextFont());
    setTextFontSize(other.getTextFontSize());
    setTextRenderingMode(other.getTextRenderingMode());
    setTextRise(other.getTextRise());
    setTextKnockout(other.getTextKnockout());
    setTextMatrix(other.getTextMatrix());
    setTextLineMatrix(other.getTextLineMatrix());
    setAlphaStroking(other.getAlphaStroking());
    setAlphaFilling(other.getAlphaFilling());
    setBlendMode(other.getBlendMode());
    setRenderingIntent(other.getRenderingIntent());
    setOverprintMode(other.getOverprintMode());
    setAlphaIsShape(other.getAlphaIsShape());
    setStrokeAdjustment(other.getStrokeAdjustment());
    setSoftMask(other.getSoftMask());
    setBlackPointCompensationMode(other.getBlackPointCompensationMode());
    setBlackGenerationFunction(other.getBlackGenerationFunction());
    setUndercolorRemovalFunction(other.getUndercolorRemovalFunction());
    setTransferFunction(other.getTransferFunction());
    setHalftone(other.getHalftone());
    setHalftoneOrigin(other.getHalftoneOrigin());
    return *this;
}

void PDFPageContentProcessor::PDFPageContentProcessorState::setCurrentTransformationMatrix(const QTransform& currentTransformationMatrix)
{
    if (m_currentTransformationMatrix != currentTransformationMatrix)
    {
        m_currentTransformationMatrix = currentTransformationMatrix;
        m_stateFlags |= StateCurrentTransformationMatrix;
    }
}

void PDFPageContentProcessor::PDFPageContentProcessorState::setStrokeColorSpace(const QSharedPointer<PDFAbstractColorSpace>& strokeColorSpace)
{
    if (m_strokeColorSpace != strokeColorSpace)
    {
        m_strokeColorSpace = strokeColorSpace;
        m_stateFlags |= StateStrokeColorSpace;
    }
}

void PDFPageContentProcessor::PDFPageContentProcessorState::setFillColorSpace(const QSharedPointer<PDFAbstractColorSpace>& fillColorSpace)
{
    if (m_fillColorSpace != fillColorSpace)
    {
        m_fillColorSpace = fillColorSpace;
        m_stateFlags |= StateFillColorSpace;
    }
}

void PDFPageContentProcessor::PDFPageContentProcessorState::setStrokeColor(const QColor& strokeColor, const PDFColor& originalColor)
{
    if (m_strokeColor != strokeColor || m_strokeColorOriginal != originalColor)
    {
        m_strokeColor = strokeColor;
        m_strokeColorOriginal = originalColor;
        m_stateFlags |= StateStrokeColor;
    }
}

void PDFPageContentProcessor::PDFPageContentProcessorState::setFillColor(const QColor& fillColor, const PDFColor& originalColor)
{
    if (m_fillColor != fillColor || m_fillColorOriginal != originalColor)
    {
        m_fillColor = fillColor;
        m_fillColorOriginal = originalColor;
        m_stateFlags |= StateFillColor;
    }
}

void PDFPageContentProcessor::PDFPageContentProcessorState::setLineWidth(PDFReal lineWidth)
{
    if (m_lineWidth != lineWidth)
    {
        m_lineWidth = lineWidth;
        m_stateFlags |= StateLineWidth;
    }
}

void PDFPageContentProcessor::PDFPageContentProcessorState::setLineCapStyle(Qt::PenCapStyle lineCapStyle)
{
    if (m_lineCapStyle != lineCapStyle)
    {
        m_lineCapStyle = lineCapStyle;
        m_stateFlags |= StateLineCapStyle;
    }
}

void PDFPageContentProcessor::PDFPageContentProcessorState::setLineJoinStyle(Qt::PenJoinStyle lineJoinStyle)
{
    if (m_lineJoinStyle != lineJoinStyle)
    {
        m_lineJoinStyle = lineJoinStyle;
        m_stateFlags |= StateLineJoinStyle;
    }
}

void PDFPageContentProcessor::PDFPageContentProcessorState::setMitterLimit(PDFReal mitterLimit)
{
    if (m_mitterLimit != mitterLimit)
    {
        m_mitterLimit = mitterLimit;
        m_stateFlags |= StateMitterLimit;
    }
}

void PDFPageContentProcessor::PDFPageContentProcessorState::setLineDashPattern(PDFLineDashPattern pattern)
{
    if (m_lineDashPattern != pattern)
    {
        m_lineDashPattern = std::move(pattern);
        m_stateFlags |= StateLineDashPattern;
    }
}

void PDFPageContentProcessor::PDFPageContentProcessorState::setRenderingIntentName(const QByteArray& renderingIntentName)
{
    if (m_renderingIntentName != renderingIntentName)
    {
        m_renderingIntentName = renderingIntentName;
        m_stateFlags |= StateRenderingIntentName;
    }
}

void PDFPageContentProcessor::PDFPageContentProcessorState::setFlatness(PDFReal flatness)
{
    if (m_flatness != flatness)
    {
        m_flatness = flatness;
        m_stateFlags |= StateFlatness;
    }
}

void PDFPageContentProcessor::PDFPageContentProcessorState::setSmoothness(PDFReal smoothness)
{
    if (m_smoothness != smoothness)
    {
        m_smoothness = smoothness;
        m_stateFlags |= StateSmoothness;
    }
}

void PDFPageContentProcessor::PDFPageContentProcessorState::setTextLeading(PDFReal textLeading)
{
    if (m_textLeading != textLeading)
    {
        m_textLeading = textLeading;
        m_stateFlags |= StateTextLeading;
    }
}

void PDFPageContentProcessor::PDFPageContentProcessorState::setTextFontSize(PDFReal textFontSize)
{
    if (m_textFontSize != textFontSize)
    {
        m_textFontSize = textFontSize;
        m_stateFlags |= StateTextFontSize;
    }
}

void PDFPageContentProcessor::PDFPageContentProcessorState::setTextKnockout(bool textKnockout)
{
    if (m_textKnockout != textKnockout)
    {
        m_textKnockout = textKnockout;
        m_stateFlags |= StateTextKnockout;
    }
}

void PDFPageContentProcessor::PDFPageContentProcessorState::setTextLineMatrix(const QTransform& textLineMatrix)
{
    if (m_textLineMatrix != textLineMatrix)
    {
        m_textLineMatrix = textLineMatrix;
        m_stateFlags |= StateTextLineMatrix;
    }
}

void PDFPageContentProcessor::PDFPageContentProcessorState::setAlphaStroking(PDFReal alpha)
{
    if (m_alphaStroking != alpha)
    {
        m_alphaStroking = alpha;
        m_stateFlags |= StateAlphaStroking;
    }
}

void PDFPageContentProcessor::PDFPageContentProcessorState::setAlphaFilling(PDFReal alpha)
{
    if (m_alphaFilling != alpha)
    {
        m_alphaFilling = alpha;
        m_stateFlags |= StateAlphaFilling;
    }
}

void PDFPageContentProcessor::PDFPageContentProcessorState::setBlendMode(BlendMode mode)
{
    if (m_blendMode != mode)
    {
        m_blendMode = mode;
        m_stateFlags |= StateBlendMode;
    }
}

void PDFPageContentProcessor::PDFPageContentProcessorState::setRenderingIntent(RenderingIntent renderingIntent)
{
    if (m_renderingIntent != renderingIntent)
    {
        m_renderingIntent = renderingIntent;
        m_stateFlags |= StateRenderingIntent;
    }
}

QColor PDFPageContentProcessor::PDFPageContentProcessorState::getStrokeColorWithAlpha() const
{
    QColor color = getStrokeColor();
    color.setAlphaF(m_alphaStroking);
    return color;
}

QColor PDFPageContentProcessor::PDFPageContentProcessorState::getFillColorWithAlpha() const
{
    QColor color = getFillColor();
    color.setAlphaF(m_alphaFilling);
    return color;
}

void PDFPageContentProcessor::PDFPageContentProcessorState::setOverprintMode(PDFOverprintMode overprintMode)
{
    if (m_overprintMode != overprintMode)
    {
        m_overprintMode = overprintMode;
        m_stateFlags |= StateOverprint;
    }
}

void PDFPageContentProcessor::PDFPageContentProcessorState::setAlphaIsShape(bool alphaIsShape)
{
    if (m_alphaIsShape != alphaIsShape)
    {
        m_alphaIsShape = alphaIsShape;
        m_stateFlags |= StateAlphaIsShape;
    }
}

bool PDFPageContentProcessor::PDFPageContentProcessorState::getStrokeAdjustment() const
{
    return m_strokeAdjustment;
}

void PDFPageContentProcessor::PDFPageContentProcessorState::setStrokeAdjustment(bool strokeAdjustment)
{
    if (m_strokeAdjustment != strokeAdjustment)
    {
        m_strokeAdjustment = strokeAdjustment;
        m_stateFlags |= StateStrokeAdjustment;
    }
}

const PDFDictionary* PDFPageContentProcessor::PDFPageContentProcessorState::getSoftMask() const
{
    return m_softMask;
}

void PDFPageContentProcessor::PDFPageContentProcessorState::setSoftMask(const PDFDictionary* softMask)
{
    if (m_softMask != softMask)
    {
        m_softMask = softMask;
        m_stateFlags |= StateSoftMask;
    }
}

BlackPointCompensationMode PDFPageContentProcessor::PDFPageContentProcessorState::getBlackPointCompensationMode() const
{
    return m_blackPointCompensationMode;
}

void PDFPageContentProcessor::PDFPageContentProcessorState::setBlackPointCompensationMode(BlackPointCompensationMode blackPointCompensationMode)
{
    if (m_blackPointCompensationMode != blackPointCompensationMode)
    {
        m_blackPointCompensationMode = blackPointCompensationMode;
        m_stateFlags |= StateBlackPointCompensation;
    }
}

PDFObject PDFPageContentProcessor::PDFPageContentProcessorState::getHalftone() const
{
    return m_halftone;
}

void PDFPageContentProcessor::PDFPageContentProcessorState::setHalftone(const PDFObject& halftone)
{
    if (m_halftone != halftone)
    {
        m_halftone = halftone;
        m_stateFlags |= StateHalftone;
    }
}

QPointF PDFPageContentProcessor::PDFPageContentProcessorState::getHalftoneOrigin() const
{
    return m_halftoneOrigin;
}

void PDFPageContentProcessor::PDFPageContentProcessorState::setHalftoneOrigin(const QPointF& halftoneOrigin)
{
    if (m_halftoneOrigin != halftoneOrigin)
    {
        m_halftoneOrigin = halftoneOrigin;
        m_stateFlags |= StateHalftoneOrigin;
    }
}

PDFObject PDFPageContentProcessor::PDFPageContentProcessorState::getTransferFunction() const
{
    return m_transferFunction;
}

void PDFPageContentProcessor::PDFPageContentProcessorState::setTransferFunction(const PDFObject& transferFunction)
{
    if (m_transferFunction != transferFunction)
    {
        m_transferFunction = transferFunction;
        m_stateFlags |= StateTransferFunction;
    }
}

PDFObject PDFPageContentProcessor::PDFPageContentProcessorState::getUndercolorRemovalFunction() const
{
    return m_undercolorRemovalFunction;
}

void PDFPageContentProcessor::PDFPageContentProcessorState::setUndercolorRemovalFunction(const PDFObject& undercolorRemovalFunction)
{
    if (m_undercolorRemovalFunction != undercolorRemovalFunction)
    {
        m_undercolorRemovalFunction = undercolorRemovalFunction;
        m_stateFlags |= StateUndercolorRemovalFunction;
    }
}

PDFObject PDFPageContentProcessor::PDFPageContentProcessorState::getBlackGenerationFunction() const
{
    return m_blackGenerationFunction;
}

void PDFPageContentProcessor::PDFPageContentProcessorState::setBlackGenerationFunction(const PDFObject& blackGenerationFunction)
{
    if (m_blackGenerationFunction != blackGenerationFunction)
    {
        m_blackGenerationFunction = blackGenerationFunction;
        m_stateFlags |= StateBlackGenerationFunction;
    }
}

void PDFPageContentProcessor::PDFPageContentProcessorState::setTextMatrix(const QTransform& textMatrix)
{
    if (m_textMatrix != textMatrix)
    {
        m_textMatrix = textMatrix;
        m_stateFlags |= StateTextMatrix;
    }
}

void PDFPageContentProcessor::PDFPageContentProcessorState::setTextRise(PDFReal textRise)
{
    if (m_textRise != textRise)
    {
        m_textRise = textRise;
        m_stateFlags |= StateTextRise;
    }
}

void PDFPageContentProcessor::PDFPageContentProcessorState::setTextRenderingMode(TextRenderingMode textRenderingMode)
{
    if (m_textRenderingMode != textRenderingMode)
    {
        m_textRenderingMode = textRenderingMode;
        m_stateFlags |= StateTextRenderingMode;
    }
}

void PDFPageContentProcessor::PDFPageContentProcessorState::setTextFont(const PDFFontPointer& textFont)
{
    if (m_textFont != textFont)
    {
        m_textFont = textFont;
        m_stateFlags |= StateTextFont;
    }
}

void PDFPageContentProcessor::PDFPageContentProcessorState::setTextHorizontalScaling(PDFReal textHorizontalScaling)
{
    if (m_textHorizontalScaling != textHorizontalScaling)
    {
        m_textHorizontalScaling = textHorizontalScaling;
        m_stateFlags |= StateTextHorizontalScaling;
    }
}

void PDFPageContentProcessor::PDFPageContentProcessorState::setTextWordSpacing(PDFReal textWordSpacing)
{
    if (m_textWordSpacing != textWordSpacing)
    {
        m_textWordSpacing = textWordSpacing;
        m_stateFlags |= StateTextWordSpacing;
    }
}

void PDFPageContentProcessor::PDFPageContentProcessorState::setTextCharacterSpacing(PDFReal textCharacterSpacing)
{
    if (m_textCharacterSpacing != textCharacterSpacing)
    {
        m_textCharacterSpacing = textCharacterSpacing;
        m_stateFlags |= StateTextCharacterSpacing;
    }
}

PDFPageContentProcessor::PDFPageContentProcessorStateGuard::PDFPageContentProcessorStateGuard(PDFPageContentProcessor* processor) :
    m_processor(processor),
    m_colorSpaceDictionary(processor->m_colorSpaceDictionary),
    m_fontDictionary(processor->m_fontDictionary),
    m_xobjectDictionary(processor->m_xobjectDictionary),
    m_extendedGraphicStateDictionary(processor->m_extendedGraphicStateDictionary),
    m_propertiesDictionary(processor->m_propertiesDictionary),
    m_shadingDictionary(processor->m_shadingDictionary),
    m_patternDictionary(processor->m_patternDictionary),
    m_procedureSets(processor->m_procedureSets)
{
    m_processor->operatorSaveGraphicState();
}

PDFPageContentProcessor::PDFPageContentProcessorStateGuard::~PDFPageContentProcessorStateGuard()
{
    // Restore dictionaries
    m_processor->m_colorSpaceDictionary = m_colorSpaceDictionary;
    m_processor->m_fontDictionary = m_fontDictionary;
    m_processor->m_xobjectDictionary = m_xobjectDictionary;
    m_processor->m_extendedGraphicStateDictionary = m_extendedGraphicStateDictionary;
    m_processor->m_propertiesDictionary = m_propertiesDictionary;
    m_processor->m_shadingDictionary = m_shadingDictionary;
    m_processor->m_patternDictionary = m_patternDictionary;
    m_processor->m_procedureSets = m_procedureSets;

    m_processor->operatorRestoreGraphicState();
}

PDFPageContentProcessor::PDFTransparencyGroupGuard::PDFTransparencyGroupGuard(PDFPageContentProcessor* processor, PDFTransparencyGroup&& group) :
    m_processor(processor)
{
    m_processor->performBeginTransparencyGroup(ProcessOrder::BeforeOperation, group);
    m_processor->m_transparencyGroupStack.push(qMove(group));
    m_processor->performBeginTransparencyGroup(ProcessOrder::AfterOperation, m_processor->m_transparencyGroupStack.top());
}

PDFPageContentProcessor::PDFTransparencyGroupGuard::~PDFTransparencyGroupGuard()
{
    m_processor->performEndTransparencyGroup(ProcessOrder::BeforeOperation, m_processor->m_transparencyGroupStack.top());
    PDFTransparencyGroup group = qMove(m_processor->m_transparencyGroupStack.top());
    m_processor->m_transparencyGroupStack.pop();
    m_processor->performEndTransparencyGroup(ProcessOrder::AfterOperation, group);
}

PDFLineDashPattern::PDFLineDashPattern(const std::vector<PDFReal>& dashArray, PDFReal dashOffset) :
    m_dashArray(dashArray),
    m_dashOffset(dashOffset)
{
    if (m_dashArray.size() % 2 == 1)
    {
        m_dashArray.push_back(m_dashArray.back());
    }
}

void PDFLineDashPattern::fix()
{
    if (m_dashOffset < 0.0)
    {
        // According to the PDF 2.0 specification, if dash offset is negative,
        // then twice of sum of lengths in the dash array should be added
        // so dash offset will become positive.

        const PDFReal totalLength = 2 * std::accumulate(m_dashArray.cbegin(), m_dashArray.cend(), 0.0);
        if (totalLength > 0.0)
        {
            m_dashOffset += (std::floor(std::abs(m_dashOffset / totalLength)) + 1.0) * totalLength;
        }
        else
        {
            // Reset to default solid line, dash pattern is invalid
            *this = PDFLineDashPattern();
        }
    }
}

QVector<qreal> PDFLineDashPattern::createForQPen(qreal penWidthF) const
{
    QVector<qreal> lineDashPattern(m_dashArray.begin(), m_dashArray.end());

    for (qreal& value : lineDashPattern)
    {
        value /= penWidthF;
    }

    return lineDashPattern;
}

PDFPageContentProcessor::PDFSoftMaskDefinition PDFPageContentProcessor::PDFSoftMaskDefinition::parse(const PDFDictionary* softMask, PDFPageContentProcessor* processor)
{
    PDFSoftMaskDefinition result;

    PDFDocumentDataLoaderDecorator loader(processor->getDocument());

    constexpr const std::array type = {
        std::pair<const char*, Type>{ "Alpha", Type::Alpha },
        std::pair<const char*, Type>{ "Luminosity", Type::Luminosity }
    };

    result.m_type = loader.readEnumByName(softMask->get("S"), type.begin(), type.end(), Type::Invalid);
    PDFObject streamObject = processor->getDocument()->getObject(softMask->get("G"));
    result.m_formStream = streamObject.isStream() ? streamObject.getStream() : nullptr;

    if (result.m_formStream)
    {
        result.m_transparencyGroup = processor->parseTransparencyGroup(result.m_formStream->getDictionary()->get("Group"));
    }

    std::vector<PDFReal> backdropColor = loader.readNumberArrayFromDictionary(softMask, "BC");
    result.m_backdropColor = PDFAbstractColorSpace::convertToColor(backdropColor);
    if (result.m_backdropColor.empty() && result.m_transparencyGroup.colorSpacePointer)
    {
        result.m_transparencyGroup.colorSpacePointer->getDefaultColorOriginal();
    }

    if (softMask->hasKey("TR"))
    {
        try
        {
            result.m_transferFunction = PDFFunction::createFunction(processor->getDocument(), softMask->get("TR"));
        }
        catch (const PDFException&)
        {
            processor->reportRenderError(RenderErrorType::Error, PDFTranslationContext::tr("Invalid soft mask transfer function."));
        }
    }

    return result;
}

}   // namespace pdf