/*
   ui/scrollbar.h
   This file is part of the Osirion project and is distributed under
   the terms of the GNU General Public License version 2
*/

#ifndef __INCLUDED_UI_SCROLLBAR_H__
#define __INCLUDED_UI_SCROLLBAR_H__

#include <string>

#include "ui/widget.h"

namespace ui
{
	
class Button;

/**
 * @brief a scrollbar widget with a vertical layout.
 */
class ScrollBar : public Widget
{
public:
	ScrollBar(Widget *parent, const float minimum = 0.0f, const float maximum = 1.0f);
	
	~ScrollBar();
	
	/**
	 * @brief the current slider value
	 */
	inline const float value() const {
		return scrollbar_value;
	}
	
	/**
	 * @brief the minimum value
	 */
	inline const float minimum() const {
		return scrollbar_minimum;
	}
	
	/**
	 * @brief the maximum value
	 */
	inline const float maximum() const {
		return scrollbar_maximum;
	}
		
	/**
	 * @brief print widget description to console
	 */
	virtual void print(const size_t indent) const;
	
	/**
	 * @brief set the current slider value
	 * @see value
	 */
	void set_value(const float value);
	
	/**
	 * @brief set the minimum slider value
	 * @see minimum
	 */
	void set_minimum(const float minimum);
	
	/**
	 * @brief set the maximum slider value
	 * @see maximum
	 */
	void set_maximum(const float maximum);

	/**
	 * @brief set the minimum and maximum slider values
	 * @see minimum
	 * @see maximum
	 */
	void set_range(const float minimum, const float maximum);

	/// show the widget
	virtual void show();

protected:
	
	/// resize event handler
	virtual void resize();
	
	/// draw event handler
	virtual void draw();
	
	/// emit event handler
	virtual bool on_emit(Widget *sender, const Event event, void *data=0);
	
	/**
	 * @brief mouse button press event handler
	 * */
	virtual bool on_mousepress(const unsigned int button);

	/**
	 * @brief mouse button release event handler
	 * */
	virtual bool on_mouserelease(const unsigned int button);
	
	/**
	 * @brief mouseover event handler
	 * */
	virtual void on_mouseover(const math::Vector2f &cursor);
	
	/**
	 * @brief mouse movement event handler
	 * */
	virtual void on_mousemove(const math::Vector2f &cursor);
	
	/**
	 * @brief mousehweel event handler
	 * */
	virtual bool on_mousewheel(const math::Vector2f & direction);
	
private:
	/// validate slider value
	void validate();
	
	float			scrollbar_minimum;
	float			scrollbar_maximum;
	float			scrollbar_value;
	bool			scrollbar_dragging;
	
	Button			*scrollbar_minbutton;
	Button			*scrollbar_decbutton;
	Button			*scrollbar_incbutton;
	Button			*scrollbar_maxbutton;
};

}

#endif // __INCLUDED_UI_SCROLLBAR_H__