/*
--------------------------------------------------------------------------------
This source file is part of SkyX.
Visit ---

Copyright (C) 2009 Xavier Verguín González <xavierverguin@hotmail.com>
                                           <xavyiy@gmail.com>

This program is free software; you can redistribute it and/or modify it under
the terms of the GNU Lesser General Public License as published by the Free Software
Foundation; either version 2 of the License, or (at your option) any later
version.

This program is distributed in the hope that it will be useful, but WITHOUT
ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details.

You should have received a copy of the GNU Lesser General Public License along with
this program; if not, write to the Free Software Foundation, Inc., 59 Temple
Place - Suite 330, Boston, MA 02111-1307, USA, or go to
http://www.gnu.org/copyleft/lesser.txt.
--------------------------------------------------------------------------------
*/

#ifndef _SkyX_CloudsManager_H_
#define _SkyX_CloudsManager_H_

#include "SkyxPrerequisites.h"
#include "SkyxColorGradient.h"

namespace SkyX
{

	/*!
	*/
	class SkyXDllExport CloudLayer 
	{
	public:
		/*!
		Layer cloud options 
		*/
		struct Options 
		{
			Ogre::Real Height;					//!< Cloud layer height
			Ogre::Real Scale;					//!< Cloud layer scale
			Ogre::Vector2 WindDirection;		//!< Wind direction
			Ogre::Real TimeMultiplier;			//!< Time multiplier
			Ogre::Real DistanceAttenuation;		//!< Distance attenuation
			Ogre::Real DetailAttenuation;		//!< Detail attenuation
			Ogre::Real NormalMultiplier;		//!< Normal multiplier
			Ogre::Real HeightVolume;			//!< Cloud layer height volume(For volumetric effects on the gpu)
			Ogre::Real VolumetricDisplacement;	//!< Volumetric displacement(For volumetric effects on the gpu)

			/*!
			Default constructor
			*/
			Options() : Height(100),
						Scale(0.001f),
						WindDirection(Ogre::Vector2(1,1)),
						TimeMultiplier(0.125f),
						DistanceAttenuation(0.05f),
						DetailAttenuation(1),
						NormalMultiplier(2),
						HeightVolume(0.25f),
						VolumetricDisplacement(0.01f)
			{
			}

			/*!
			Constructor
			@param _Height Cloud layer height
			@param _Scale Clouds scale
			@param _WindDirection Clouds movement direction
			@param _TimeMultiplier Time multiplier factor
			*/
			Options(const Ogre::Real& _Height, const Ogre::Real& _Scale, const Ogre::Vector2& _WindDirection, const Ogre::Real& _TimeMultiplier) : Height(_Height),
																																				   Scale(_Scale),
																																				   WindDirection(_WindDirection),
																																				   TimeMultiplier(_TimeMultiplier),
																																				   DistanceAttenuation(0.05f),
																																				   DetailAttenuation(1),
																																				   NormalMultiplier(2),
																																				   HeightVolume(0.25f),
																																				   VolumetricDisplacement(0.01f)
			{
			}

			/*!Constructor
			@param _Height Cloud layer height
			@param _Scale Clouds scale
			@param _WindDirection Clouds movement direction
			@param _TimeMultiplier Time multiplier factor
			@param _DistanceAttenuation Distance attenuation
			@param _DetailAttenuation Detail attenuation
			@param _NormalMultiplier Normal multiplier coeficient
			@param _HeightVolume Height volume(For volumetric effects on the gpu)
			@param _VolumetricDisplacement Volumetric displacement(For volumetric effects on the gpu)
			*/
			Options(const Ogre::Real& _Height, const Ogre::Real& _Scale, const Ogre::Vector2& _WindDirection, const Ogre::Real& _TimeMultiplier,
					const Ogre::Real& _DistanceAttenuation,	const Ogre::Real& _DetailAttenuation, 
					const Ogre::Real& _NormalMultiplier, const Ogre::Real& _HeightVolume, const Ogre::Real& _VolumetricDisplacement) : Height(_Height),
																																	   Scale(_Scale),
																																	   WindDirection(_WindDirection),
																																	   TimeMultiplier(_TimeMultiplier),
																																	   DistanceAttenuation(_DistanceAttenuation),
																																	   DetailAttenuation(_DetailAttenuation),
																																	   NormalMultiplier(_NormalMultiplier),
																																	   HeightVolume(_HeightVolume),
																																	   VolumetricDisplacement(_VolumetricDisplacement)
			{
			}
		};
	protected:
	private:
		Options mOptions;				        //!< Cloud layer options
		ColorGradient mAmbientGradient;	//!< Ambient color gradient
		ColorGradient mSunGradient;		  //!< Sun color gradient
		Ogre::Pass* mCloudLayerPass;	  //!< Cloud layer pass
		SkyX* mSkyX;					          //!< SkyX parent pointer

	public:
		/*!
		Default onstructor
		@param s SkyX parent pointer
		*/
		CloudLayer(SkyX* s);

		/*!
		Constructor
		@param s SkyX parent pointer
		@param o Cloud layer options
		*/
		CloudLayer(SkyX* s, const Options& o);

		/*!
		Destructor
		*/
        ~CloudLayer();

		/*!
		Get options
		@return Cloud layer options
		*/
		inline const Options& getOptions() const
		{
			return mOptions;
		}

    /*!
		Update options
		@param newOptions Cloud layer options
		*/
		void setOptions(const Options& newOptions);

		/*!
		Set ambient gradient
		@param AmbientGradient Ambient color gradient
		*/
		inline void setAmbientGradient(const ColorGradient& AmbientGradient)
		{
			mAmbientGradient = AmbientGradient;
		}

		/*!
		Get ambient color gradient
		@return Ambient color gradient
		*/
		inline const ColorGradient& getAmbientGradient() const
		{
			return mAmbientGradient;
		}

		/*!
		Set sun gradient
		@param SunGradient Sun color gradient
		*/
		inline void setSunGradient(const ColorGradient& SunGradient)
		{
			mSunGradient = SunGradient;
		}

		/*!
		Get sun color gradient
		@return Sun color gradient
		*/
		inline const ColorGradient& getSunGradient() const
		{
			return mSunGradient;
		}

		/*!
		Register layer
		@param CloudLayerPass Pass where register the cloud layer
		*/
		void _registerCloudLayer(Ogre::Pass* CloudLayerPass);

		/*!
		Unregister cloud pass
		*/
		void _unregister();

		/*!
		Update internal cloud pass parameters
		*/
		void _updateInternalPassParameters();
	protected:
	private:
		/*!
		Update cloud pass parameters
		*/
		void _updatePassParameters();
	};

	/*!
	*/
  class SkyXDllExport CloudsManager 
	{
	public:
	protected:
	private:
		std::vector<CloudLayer*> mCloudLayers;				//!< Cloud layers std::vector
		std::vector<CloudLayer*>::iterator CloudLayersIt;	//!< Cloud layers iterator
		SkyX *mSkyX;										//!< SkyX parent pointer

	public:
		/*!
		Constructor
		@param s SkyX parent pointer
		 */
		CloudsManager(SkyX *h);

		/*!
		Destructor
		*/
    ~CloudsManager();

		/*!
		Add a cloud layer
		@param o Cloud layer options
		@return Cloud layer
		*/
		CloudLayer* add(const CloudLayer::Options& o);

		/*!
		Remove the specified cloud layer
		*/
		void remove(CloudLayer* cl);

		/*!
		Remove all cloud layers
		*/
		void removeAll();

		/*!
		Register all
		*/
		void registerAll();

		/*!
		Unregister cloud layer
		@param cl Cloud layer to be unregistered
		*/
		void unregister(CloudLayer* cl);

		/*!
		Unregister all cloud layers
		*/
		void unregisterAll();

		/*!
		Update internall cloud layer parameters
		*/
		void _updateInternal();
	protected:
	private:
	};

}

#endif