GeoDataObject.h

// SPDX-License-Identifier: LGPL-2.1-or-later
//
// SPDX-FileCopyrightText: 2007 Murad Tagirov <tmurad@gmail.com>
// SPDX-FileCopyrightText: 2008 Jens-Michael Hoffmann <jensmh@gmx.de>
//
 
#ifndef MARBLE_GEODATAOBJECT_H
#define MARBLE_GEODATAOBJECT_H
 
#include "geodata_export.h"
 
#include "GeoDocument.h"
#include "Serializable.h"
 
#include <QMetaType>
 
namespace Marble
{
 
class GeoDataObjectPrivate;
 
/**
 * @short A base class for all geodata objects
 *
 * GeoDataObject is the base class for all geodata classes. It is
 * never instantiated by itself, but is always used as part of a
 * derived object.
 *
 * The Geodata objects are all modeled after the Google KML files as
 * defined in
 * https://developers.google.com/kml/documentation/kmlreference.
 *
 * A GeoDataObject contains 2 properties, both corresponding directly
 * to tags in the KML files: the <b>id</b>, which is a unique
 * identifier of the object, and a <b>targetId</b> which is used to
 * reference other objects that have already been loaded.
 *
 * The <b>id</b> property must only be set if the <b>Update</b>
 * mechanism of KML is used, which is currently not supported by
 * Marble.
 */
class GEODATA_EXPORT GeoDataObject : public GeoNode, public Serializable
{
public:
    GeoDataObject();
    GeoDataObject(const GeoDataObject &);
    GeoDataObject &operator=(const GeoDataObject &);
    ~GeoDataObject() override;
 
    /// Provides the parent of the object in GeoDataContainers
    const GeoDataObject *parent() const;
    GeoDataObject *parent();
 
    /// Sets the parent of the object
    void setParent(GeoDataObject *parent);
 
    /**
     * @brief Get the id of the object.
     */
    QString id() const;
    /**
     * @brief Set the id of the object
     * @param value the new id value
     */
    void setId(const QString &value);
 
    /**
     * @brief Get the targetId of the object to be replaced
     */
    QString targetId() const;
    /**
     * @brief set a new targetId of this object
     * @param value the new targetId value
     */
    void setTargetId(const QString &value);
 
    QString resolvePath(const QString &relativePath) const;
 
    /// Reimplemented from Serializable
    void pack(QDataStream &stream) const override;
    /// Reimplemented from Serializable
    void unpack(QDataStream &steam) override;
 
private:
    GeoDataObjectPrivate *const d;
 
protected:
    /**
     * @brief Compares the value of id and targetId of the two objects
     * @return true if they these values are equal or false otherwise
     */
    virtual bool equals(const GeoDataObject &other) const;
};
 
/**
 * Returns the given node cast to type T if the node was instantiated as type T; otherwise returns 0.
 * If node is 0 then it will also return 0.
 *
 * @param node pointer to GeoNode object to be casted
 * @return the given node as type T if cast is successful, otherwise 0
 */
template<typename T>
T *geodata_cast(GeoDataObject *node)
{
    if (node == nullptr) {
        return nullptr;
    }
 
    if (typeid(*node) == typeid(T)) {
        return static_cast<T *>(node);
    }
 
    return nullptr;
}
 
/**
 * Returns the given node cast to type const T if the node was instantiated as type T; otherwise returns 0.
 * If node is 0 then it will also return 0.
 *
 * @param node pointer to GeoNode object to be casted
 * @return the given node as type const T if cast is successful, otherwise 0
 */
template<typename T>
const T *geodata_cast(const GeoDataObject *node)
{
    if (node == nullptr) {
        return nullptr;
    }
 
    if (typeid(*node) == typeid(T)) {
        return static_cast<const T *>(node);
    }
 
    return nullptr;
}
 
}
 
Q_DECLARE_METATYPE(Marble::GeoDataObject *)
 
#endif