#ifndef ENERGYSAVER_H
#define ENERGYSAVER_H

#include <QObject>
#include <QTimer>

/**
 * @brief Class handling energy saving options.
 *
 * Shut down device if no mouse input is detected and music player
 * has not been active or a certain time interval.
 *
 * @todo For now this does only work for Lena's RasPi, where the
 * shutdown script is positioned in a ceratin hardcoded path.
 * Enable/disable energy saving option, timeout and path of
 * shutdown script via config
 */
class EnergySaver : public QObject
{
    Q_OBJECT

protected:
    explicit EnergySaver(QObject *parent = nullptr) : QObject(parent) {}

public:
    /**
     * @brief Create instance if necessary, configure it and start timer.
     * @param interval Timer interval in seconds
     * @param shutdownScript Path to shutdown script file
     * @see EnergySaver::instance
     *
     * Instance is initialized with timeout interval and shutdown script
     * and started if the provided script exists.
     */
    static void init(int interval, const QString& shutdownScript);
    /**
     * @brief Implements the singleton pattern.
     * @return Instance of EnergySaver
     *
     * If no instance has been created yet, create new instance.
     */
    static EnergySaver *instance();

public slots:
    /**
     * @brief Restart shutdown timer, e.g. because of music player activiti
     */
    void restartTimer();

private:
    /**
     * @brief Initialize and connect timer.
     * @param interval Timeout interval in millisecond.
     */
    void initTimer(int interval);
    void setShutdownScript(const QString& shutdownScript);
    QTimer mTimer;
    QString mShutdownScript;

private slots:
    /**
     * @brief Behavior on timeout: shut down RaspberryPi.
     */
    void onTimeout();

};

#endif // ENERGYSAVER_H