//********************************** Banshee Engine (www.banshee3d.com) **************************************************//
//**************** Copyright (c) 2016 Marko Pintera (marko.pintera@gmail.com). All rights reserved. **********************//
#pragma once

#include "BsEditorPrerequisites.h"
#include "Math/BsVector2I.h"

namespace bs
{
	/** @addtogroup EditorWindow
	 *  @{
	 */

	/** This is a generic GUI drop down window class that can be used for displaying custom drop down content. */
	class BS_ED_EXPORT DropDownWindow
	{
	public:
		virtual ~DropDownWindow();

		/**	Returns width of the window in pixels. */
		UINT32 getWidth() const { return mWidth; }
		
		/**	Returns height of the window in pixels. */
		UINT32 getHeight() const { return mHeight; }

		/**	Converts screen pointer coordinates into coordinates relative to the window contents GUI panel. */
		Vector2I screenToWindowPos(const Vector2I& screenPos) const;

		/**	Converts pointer coordinates relative to the window contents GUI panel into screen coordinates. */
		Vector2I windowToScreenPos(const Vector2I& windowPos) const;

		/**	Returns the GUI widget used for displaying all GUI contents in the window. */
		HGUIWidget getGUIWidget() const { return mGUI; }

		/**
		 * Changes the size of the drop down window area.
		 *			
		 * @note	This might reposition the window if the new size doesn't fit at the current position.
		 */
		void setSize(UINT32 width, UINT32 height);

		/**	Closes the drop down window. */
		void close();

		/**	Called once every frame. Internal method. */
		virtual void update() { }

	protected:
		DropDownWindow(const SPtr<RenderWindow>& parent, const SPtr<Camera>& camera,
			const Vector2I& position, UINT32 width = 200, UINT32 height = 200);

		GUIPanel* mContents;

	private:
		friend class DropDropWindowManager;

		/**	Triggered when the user clicks outside of the drop down area. */
		void dropDownFocusGained();

		SPtr<RenderWindow> mRenderWindow;
		HSceneObject mSceneObject;
		HGUIWidget mGUI;

		GUIDropDownHitBox* mFrontHitBox;
		GUIDropDownHitBox* mBackHitBox;
		GUIPanel* mRootPanel;
		Vector2I mPosition;
		UINT32 mWidth;
		UINT32 mHeight;
	};

	/** @} */
}