/**
  * @RDE_HEADER@
  * A special slider for zooming
  * $Id$
  * $HeadURL$
  * $Author$
  */

#pragma once

#include <QWidget>

class QLabel;
class QSlider;

namespace THP
{
/**
  * An specialized QSlider
  * This slider has a special, fixed range from 0.1 - 100 which is mapped to
  * suitable map scales used in the GUEZ.
  * The scale is not linear - instead it has a model behind. in smaller scales -
  * slider's going to 0.1 - it's resolution is finer than on larger scales -
  * slider's going to 100.
  * The slider accpets only values within the range 0.1....100. Other values are ignored.
  */
class ZoomSlider : public QWidget
{
  Q_OBJECT
  Q_PROPERTY(Qt::Orientation Orientation READ getOrientation WRITE setOrientation)
  Q_PROPERTY(bool showDescriptionLabel READ getShowDescriptionLabel WRITE setShowDescriptionLabel)
  Q_PROPERTY(bool showValueLabel READ getShowValueLabel WRITE setShowValueLabel)

public:

  /**
   * constructor
   */
  explicit ZoomSlider(QWidget *parent = nullptr);

  /**
   * get the actual Zoom value.
   * @return float with the zoom value
   */
  double getZoomValue() const;

  /**
   * Sets the Orientation.
   * @param a_orientation The slider's orientation.
   */
  void setOrientation(Qt::Orientation a_orientation);

  /**
   *
   */
  Qt::Orientation getOrientation() const;

  bool getShowDescriptionLabel() const;
  void setShowDescriptionLabel(bool bVisible);

  bool getShowValueLabel() const;
  void setShowValueLabel(bool bVisible);

  /**
    * format the given value as it would be shown in the zoom label
    */
  QString formatValue(double value) const;

public Q_SLOTS:
  /**
   * set the slider's actual zoom value. This is a QT-Slot.
   * The slider accpet only values within it's range 0.1...100.
   * Other values are ignored.
   * @param a_zoomValue the new zoom value.
   */
  void setZoomValue(double zoomValue);

Q_SIGNALS:
  /**
   * A QT-Signal which is emitted whenever the slider's value has changed.
   * The newly set zoom value is delivered as argument.
   */
  void valueChanged(double a_value);


private Q_SLOTS:
  /**
    * Update the label text
    */
  void updateLabel(double newValue);
private:

  /**
   * Contains the slider's minimum zoom value
   */
  const double m_InternalMin;
  /**
   * Contains the slider's maximum zoom value
   */
  const double m_InternalMax;
  /**
   * Contains the slider's lower threshold value.
   * The lower threshold is at 50% of the sliders range.
   */
  const int m_LowerThreshold;
  /**
   * Contains the slider's upper threshold value.
   * The upper threshold is at 75% of the sliders range.
   */
  const int m_UpperThreshold;
  /**
   * Contains the slider's range minimum value
   */
  const int m_MinRange;
  /**
   * Contains the slider's range maximum value
   */
  const int m_MaxRange;

  /**
   * The QSlider
   */
  QSlider *m_Slider;

  /**
   * The label for showing the exact slider value.
   */
  QLabel *m_lbl;

  /**
   * The label for showing the 'zoom' text
   */
  QLabel *m_text;

  /**
   * contains the zoom value
   */
  double m_ZoomValue;

  /**
    * The current value of the slider to avoid loops
    */
  int m_curSliderVal;

private slots :
  /**
   * Calculates the zoom value from the slider's position
   */
  void calcZoomFromSlider(int a_value);

};
} // namespace THP