#ifndef STYLECONTROLLER_H
#define STYLECONTROLLER_H

#include <QObject>
#include <QQmlContext>
#include <QQmlPropertyMap>

/**
 * @brief Contains all style sizes, margins and paddings used throughout the application
 *
 * Based on a reference screen size, maps for scaled margins, paddings and spacings are created and
 * registered in the QML context. The values stored in the maps can then be used from QML.
 * Map names: StyleSizes, StylePaddings, StyleSpacings, StyleMargins
 *
 * Always use values from these maps in QML! Never use magic numbers! They will NOT scale when
 * the application is run on a different screen.
 *
 * See https://doc.qt.io/qt-5/scalability.html
 *
 * @todo scale fonts as well?
 * @todo use dpi for scaling as app is very small on Android?
 */
class StyleController : public QObject
{
    Q_OBJECT
public:
    explicit StyleController(QObject *parent = nullptr);

    /**
     * @brief Calculates ratio, initializes all maps and registers them in QML context
     * @param context Context to register Maps in
     */
    void init(QQmlContext* context);

private:
    /**
     * @brief Calculates ratio from reference screen size and size of the current primary screen and inits member mRatio
     */
    void calculateAndSetRatio();
    /**
     * @brief Initializes map containing all sizes (e.g., button or delegate sizes)
     */
    void initStyleSizes();
    /**
     * @brief Initializes map containing all spacings
     */
    void initSpacings();
    /**
     * @brief Initializes map containing all margins
     */
    void initMargins();
    /**
     * @brief Initializes map containing all paddings
     */
    void initPaddings();
    /**
     * @brief Scales the value with calculated ratio and inserts it into the given map under the given key
     * @param map Map to insert key-value pair into
     * @param key Key used in the map. This is the name used to retrieve the value in QML
     * @param value Unscaled value
     * @see mRatio
     *
     * In QML the value with the key "defaulSpacing" in the Map "StyleSpacings" is accessed by StyleSpacings.defaultSpacing
     */
    void scaleAndInsert(QQmlPropertyMap* map, const QString& key, int value);
    /**
     * @brief Applys ratio to given size
     * @param size Size to be scaled
     * @return scaled size
     * @see mRatio
     */
    int applyRatio(int size) const;

    qreal mRatio = 1.0;
    QQmlPropertyMap* mStyleSizes = nullptr;
    QQmlPropertyMap* mMargins = nullptr;
    QQmlPropertyMap* mSpacings = nullptr;
    QQmlPropertyMap* mPaddings = nullptr;
};

#endif // STYLECONTROLLER_H