/*
  Copyright (C)  2006  Brad Hards <bradh@frogmouth.net>

  This program is free software; you can redistribute it and/or
  modify it under the terms of the GNU General Public License
  as published by the Free Software Foundation; either version 2
  of the License, or (at your option) any later version

  This program is distributed in the hope that it will be useful,
  but WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  GNU General Public License for more details.

  You should have received a copy of the GNU General Public License
  along with this program; if not, write to the Free Software
  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  02110-1301, USA.
*/

#ifndef _OKULAR_GENERATOR_XPS_H_
#define _OKULAR_GENERATOR_XPS_H_

#include <core/generator.h>
#include <core/textpage.h>

#include <QColor>
#include <QDomDocument>
#include <QFontDatabase>
#include <QImage>
#include <QLoggingCategory>
#include <QStack>
#include <QVariant>
#include <QXmlDefaultHandler>
#include <QXmlStreamReader>

#include <kzip.h>

typedef enum { abtCommand, abtNumber, abtComma, abtEOF } AbbPathTokenType;

class AbbPathToken
{
public:
    QString data;
    int curPos;

    AbbPathTokenType type;
    char command;
    double number;
};

/**
    Holds information about xml element during SAX parsing of page
*/
class XpsRenderNode
{
public:
    QString name;
    QVector<XpsRenderNode> children;
    QXmlAttributes attributes;
    QVariant data;

    const XpsRenderNode *findChild(const QString &name) const;
    QVariant getRequiredChildData(const QString &name) const;
    QVariant getChildData(const QString &name) const;
};

struct XpsGradient {
    XpsGradient(double o, const QColor &c)
        : offset(o)
        , color(c)
    {
    }

    double offset;
    QColor color;
};

/**
    Types of data in XpsRenderNode::data. Name of each type consist of Xps and
    name of xml element which data it holds
*/
typedef QTransform XpsMatrixTransform;
typedef QTransform XpsRenderTransform;
typedef QBrush XpsFill;
struct XpsPathFigure {
    XpsPathFigure(const QPainterPath &_path, bool filled)
        : path(_path)
        , isFilled(filled)
    {
    }

    QPainterPath path;
    bool isFilled;
};
struct XpsPathGeometry {
    XpsPathGeometry()
        : fillRule(Qt::OddEvenFill)
    {
    }
    ~XpsPathGeometry()
    {
        qDeleteAll(paths);
    }

    XpsPathGeometry(const XpsPathGeometry &) = delete;
    XpsPathGeometry &operator=(const XpsPathGeometry &) = delete;

    QList<XpsPathFigure *> paths;
    Qt::FillRule fillRule;
    XpsMatrixTransform transform;
};

class XpsPage;
class XpsFile;

class XpsHandler : public QXmlDefaultHandler
{
public:
    explicit XpsHandler(XpsPage *page);
    ~XpsHandler() override;

    bool startElement(const QString &nameSpace, const QString &localName, const QString &qname, const QXmlAttributes &atts) override;
    bool endElement(const QString &nameSpace, const QString &localName, const QString &qname) override;
    bool startDocument() override;

protected:
    XpsPage *m_page;

    void processStartElement(XpsRenderNode &node);
    void processEndElement(XpsRenderNode &node);

    // Methods for processing of different xml elements
    void processGlyph(XpsRenderNode &node);
    void processPath(XpsRenderNode &node);
    void processPathData(XpsRenderNode &node);
    void processFill(XpsRenderNode &node);
    void processStroke(XpsRenderNode &node);
    void processImageBrush(XpsRenderNode &node);
    void processPathGeometry(XpsRenderNode &node);
    void processPathFigure(XpsRenderNode &node);

    QPainter *m_painter;

    QImage m_image;

    QStack<XpsRenderNode> m_nodes;

    friend class XpsPage;
};

class XpsPage
{
public:
    XpsPage(XpsFile *file, const QString &fileName);
    ~XpsPage();

    XpsPage(const XpsPage &) = delete;
    XpsPage &operator=(const XpsPage &) = delete;

    QSizeF size() const;
    bool renderToImage(QImage *p);
    bool renderToPainter(QPainter *painter);
    Okular::TextPage *textPage();

    QImage loadImageFromFile(const QString &filename);
    QString fileName() const
    {
        return m_fileName;
    }

private:
    XpsFile *m_file;
    const QString m_fileName;

    QSizeF m_pageSize;

    QString m_thumbnailFileName;
    bool m_thumbnailMightBeAvailable;
    QImage m_thumbnail;
    bool m_thumbnailIsLoaded;

    QImage *m_pageImage;
    bool m_pageIsRendered;

    friend class XpsHandler;
    friend class XpsTextExtractionHandler;
};

/**
   Represents one of the (perhaps the only) documents in an XpsFile
*/
class XpsDocument
{
public:
    XpsDocument(XpsFile *file, const QString &fileName);
    ~XpsDocument();

    XpsDocument(const XpsDocument &) = delete;
    XpsDocument &operator=(const XpsDocument &) = delete;

    /**
       the total number of pages in this document
    */
    int numPages() const;

    /**
       obtain a certain page from this document

       \param pageNum the number of the page to return

       \note page numbers are zero based - they run from 0 to
       numPages() - 1
    */
    XpsPage *page(int pageNum) const;

    /**
      whether this document has a Document Structure
    */
    bool hasDocumentStructure();

    /**
      the document structure for this document, if available
    */
    const Okular::DocumentSynopsis *documentStructure();

private:
    void parseDocumentStructure(const QString &documentStructureFileName);

    QList<XpsPage *> m_pages;
    XpsFile *m_file;
    bool m_haveDocumentStructure;
    Okular::DocumentSynopsis *m_docStructure;
    QMap<QString, int> m_docStructurePageMap;
};

/**
   Represents the contents of a Microsoft XML Paper Specification
   format document.
*/
class XpsFile
{
public:
    XpsFile();
    ~XpsFile();

    XpsFile(const XpsFile &) = delete;
    XpsFile &operator=(const XpsFile &) = delete;

    bool loadDocument(const QString &fileName);
    bool closeDocument();

    Okular::DocumentInfo generateDocumentInfo() const;

    QImage thumbnail();

    /**
       the total number of XpsDocuments with this file
    */
    int numDocuments() const;

    /**
       the total number of pages in all the XpsDocuments within this
       file
    */
    int numPages() const;

    /**
       a page from the file

        \param pageNum the page number of the page to return

        \note page numbers are zero based - they run from 0 to
        numPages() - 1
    */
    XpsPage *page(int pageNum) const;

    /**
       obtain a certain document from this file

       \param documentNum the number of the document to return

       \note document numbers are zero based - they run from 0 to
       numDocuments() - 1
    */
    XpsDocument *document(int documentNum) const;

    QFont getFontByName(const QString &absoluteFileName, float size);

    KZip *xpsArchive();

private:
    int loadFontByName(const QString &absoluteFileName);

    QList<XpsDocument *> m_documents;
    QList<XpsPage *> m_pages;

    QString m_thumbnailFileName;
    bool m_thumbnailMightBeAvailable;
    QImage m_thumbnail;
    bool m_thumbnailIsLoaded;

    QString m_corePropertiesFileName;

    QString m_signatureOrigin;

    KZip *m_xpsArchive;

    QMap<QString, int> m_fontCache;
    QFontDatabase m_fontDatabase;
};

class XpsGenerator : public Okular::Generator
{
    Q_OBJECT
    Q_INTERFACES(Okular::Generator)
public:
    XpsGenerator(QObject *parent, const QVariantList &args);
    ~XpsGenerator() override;

    bool loadDocument(const QString &fileName, QVector<Okular::Page *> &pagesVector) override;

    Okular::DocumentInfo generateDocumentInfo(const QSet<Okular::DocumentInfo::Key> &keys) const override;
    const Okular::DocumentSynopsis *generateDocumentSynopsis() override;

    Okular::ExportFormat::List exportFormats() const override;
    bool exportTo(const QString &fileName, const Okular::ExportFormat &format) override;

    bool print(QPrinter &printer) override;

protected:
    bool doCloseDocument() override;
    QImage image(Okular::PixmapRequest *request) override;
    Okular::TextPage *textPage(Okular::TextRequest *request) override;

private:
    XpsFile *m_xpsFile;
};

Q_DECLARE_LOGGING_CATEGORY(OkularXpsDebug)

#endif