HOCRDocument.hh

/* -*- Mode: C++; indent-tabs-mode: t; c-basic-offset: 4; tab-width: 4 -*-  */
/*
 * HOCRDocument.hh
 * Copyright (C) 2013-2018 Sandro Mani <manisandro@gmail.com>
 *
 * gImageReader 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 3 of the License, or
 * (at your option) any later version.
 *
 * gImageReader 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, see <http://www.gnu.org/licenses/>.
 */

#ifndef HOCRDOCUMENT_HH
#define HOCRDOCUMENT_HH

#include <QAbstractItemModel>
#include <QDomDocument>
#include <QRect>

class HOCRItem;
class HOCRPage;

class HOCRDocument : public QAbstractItemModel {
    Q_OBJECT

public:
    HOCRDocument(QObject* parent = 0);
    ~HOCRDocument();

    void clear();

    void setDefaultLanguage(const QString& language) {
        m_defaultLanguage = language;
    }

    QString toHTML() const;

    QModelIndex addPage(const QDomElement& pageElement, bool cleanGraphics);
    const HOCRPage* page(int i) const {
        return m_pages.value(i);
    }
    int pageCount() const {
        return m_pages.size();
    }

    const HOCRItem* itemAtIndex(const QModelIndex& index) const {
        return index.isValid() ? static_cast<HOCRItem*>(index.internalPointer()) : nullptr;
    }
    bool editItemAttribute(const QModelIndex& index, const QString& name, const QString& value, const QString& attrItemClass = QString());
    QModelIndex moveItem(const QModelIndex& itemIndex, const QModelIndex& newParent, int row);
    QModelIndex swapItems(const QModelIndex& parent, int startRow, int endRow);
    QModelIndex mergeItems(const QModelIndex& parent, int startRow, int endRow);
    QModelIndex splitItem(const QModelIndex& item, int startRow, int endRow);
    QModelIndex addItem(const QModelIndex& parent, const QDomElement& element);
    bool removeItem(const QModelIndex& index);

    QModelIndex nextIndex(const QModelIndex& current);
    QModelIndex prevIndex(const QModelIndex& current);

    bool referencesSource(const QString& filename) const;
    QModelIndex searchPage(const QString& filename, int pageNr) const;
    QModelIndex searchAtCanvasPos(const QModelIndex& pageIndex, const QPoint& pos) const;
    void convertSourcePaths(const QString& basepath, bool absolute);

    QVariant data(const QModelIndex& index, int role) const override;
    bool setData(const QModelIndex& index, const QVariant& value, int role) override;
    Qt::ItemFlags flags(const QModelIndex& index) const override;
    QModelIndex index(int row, int column, const QModelIndex& parent = QModelIndex()) const override;
    QModelIndex parent(const QModelIndex& child) const override;
    int rowCount(const QModelIndex& parent = QModelIndex()) const override;
    int columnCount(const QModelIndex& parent = QModelIndex()) const override;

signals:
    void itemAttributeChanged(const QModelIndex& itemIndex, const QString& name, const QString& value);

private:
    int m_pageIdCounter = 0;
    QString m_defaultLanguage = "en_US";

    QVector<HOCRPage*> m_pages;

    QString displayRoleForItem(const HOCRItem* item) const;
    QIcon decorationRoleForItem(const HOCRItem* item) const;

    bool checkItemSpelling(const HOCRItem* item) const;
    void insertItem(HOCRItem* parent, HOCRItem* item, int i);
    void deleteItem(HOCRItem* item);
    void takeItem(HOCRItem* item);
    void recursiveDataChanged(const QModelIndex& parent, const QVector<int>& roles, const QStringList& itemClasses = QStringList());
    void recomputeBBoxes(HOCRItem* item);
    HOCRItem* mutableItemAtIndex(const QModelIndex& index) const {
        return index.isValid() ? static_cast<HOCRItem*>(index.internalPointer()) : nullptr;
    }
};

class HOCRItem {
public:
    // attrname : attrvalue : occurences
    typedef QMap<QString, QMap<QString, int>> AttrOccurenceMap_t;

    HOCRItem(const QDomElement& element, HOCRPage* page, HOCRItem* parent, int index = -1);
    virtual ~HOCRItem();
    HOCRPage* page() const {
        return m_pageItem;
    }
    const QVector<HOCRItem*>& children() const {
        return m_childItems;
    }
    HOCRItem* parent() const {
        return m_parentItem;
    }
    int index() const {
        return m_index;
    }
    bool isEnabled() const {
        return m_enabled;
    }

    // HOCR specific convenience getters
    QString itemClass() const {
        return m_attrs["class"];
    }
    const QRect& bbox() const {
        return m_bbox;
    }
    QString text() const {
        return m_text;
    }
    QString lang() const {
        return m_attrs["lang"];
    }
    const QMap<QString, QString> getAttributes() const {
        return m_attrs;
    }
    const QMap<QString, QString> getTitleAttributes() const {
        return m_titleAttrs;
    }
    QMap<QString, QString> getAllAttributes() const;
    QMap<QString, QString> getAttributes(const QList<QString>& names) const;
    void getPropagatableAttributes(QMap<QString, QMap<QString, QSet<QString> > >& occurences) const;
    QString toHtml(int indent = 0) const;
    QPair<double, double> baseLine() const;
    QString fontFamily() const {
        return m_titleAttrs["x_font"];
    }
    double fontSize() const {
        return m_titleAttrs["x_fsize"].toDouble();
    }
    bool fontBold() const {
        return m_bold;
    }
    bool fontItalic() const {
        return m_italic;
    }

    void addChild(HOCRItem* child);
    void insertChild(HOCRItem* child, int index);
    void removeChild(HOCRItem* child);
    void takeChild(HOCRItem* child);
    QVector<HOCRItem*> takeChildren();
    void setEnabled(bool enabled) {
        m_enabled = enabled;
    }
    void setText(const QString& newText) {
        m_text = newText;
    }
    void setAttribute(const QString& name, const QString& value, const QString& attrItemClass = QString());

    static QMap<QString, QString> deserializeAttrGroup(const QString& string);
    static QString serializeAttrGroup(const QMap<QString, QString>& attrs);
    static QString trimmedWord(const QString& word, QString* prefix = nullptr, QString* suffix = nullptr);

protected:
    friend class HOCRDocument;
    friend class HOCRPage;

    static QMap<QString, QString> s_langCache;

    QString m_text;
    bool m_bold;
    bool m_italic;

    QMap<QString, QString> m_attrs;
    QMap<QString, QString> m_titleAttrs;
    QVector<HOCRItem*> m_childItems;
    HOCRPage* m_pageItem = nullptr;
    HOCRItem* m_parentItem = nullptr;
    int m_index;
    bool m_enabled = true;

    QRect m_bbox;

    bool parseChildren(const QDomElement& element, QString language);
};


class HOCRPage : public HOCRItem {
public:
    HOCRPage(const QDomElement& element, int pageId, const QString& language, bool cleanGraphics, int index);

    const QString& sourceFile() const {
        return m_sourceFile;
    }
    // const-refs here to avoid taking reference from temporaries
    const int& pageNr() const {
        return m_pageNr;
    }
    const double& angle() const {
        return m_angle;
    }
    const int& resolution() const {
        return m_resolution;
    }
    int pageId() const {
        return m_pageId;
    }
    QString title() const;

private:
    friend class HOCRItem;
    friend class HOCRDocument;

    int m_pageId;
    QMap<QString, int> m_idCounters;
    QString m_sourceFile;
    int m_pageNr;
    double m_angle;
    int m_resolution;

    void convertSourcePath(const QString& basepath, bool absolute);
};


#endif // HOCRDOCUMENT_HH