/*
-----------------------------------------------------------------------------
This source file is part of OGRE
(Object-oriented Graphics Rendering Engine)
For the latest info, see http://www.ogre3d.org

Copyright (c) 2000-2013 Torus Knot Software Ltd
Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
THE SOFTWARE.
-----------------------------------------------------------------------------
*/
#ifndef _ShaderParameter_
#define _ShaderParameter_

#include "OgreShaderPrerequisites.h"
#include "OgreGpuProgram.h"
#include "OgreVector2.h"
#include "OgreVector3.h"
#include "OgreVector4.h"
#include "OgreMatrix4.h"

namespace Ogre {
namespace RTShader {

/** \addtogroup Core
*  @{
*/
/** \addtogroup RTShader
*  @{
*/

/** A class that represents a shader based program parameter.
*/
class _OgreRTSSExport Parameter : public RTShaderSystemAlloc
{
public:
	// Shader parameter semantic.
	enum Semantic
	{
		/// Unknown semantic
		SPS_UNKNOWN = 0,
		/// Position
		SPS_POSITION = 1,
		/// Blending weights
		SPS_BLEND_WEIGHTS = 2,
		/// Blending indices
		SPS_BLEND_INDICES = 3,
		/// Normal, 3 reals per vertex
		SPS_NORMAL = 4,
		/// General floating point color.
		SPS_COLOR = 5,		
		/// Texture coordinates
		SPS_TEXTURE_COORDINATES = 7,
		/// Binormal (Y axis if normal is Z)
		SPS_BINORMAL = 8,
		/// Tangent (X axis if normal is Z)
		SPS_TANGENT = 9		
	};

	// Shader parameter content.
	enum Content
	{
		/// Unknown content
		SPC_UNKNOWN,

		/// Position in object space
		SPC_POSITION_OBJECT_SPACE,

		/// Position in world space
		SPC_POSITION_WORLD_SPACE,

		/// Position in view space
		SPC_POSITION_VIEW_SPACE,

		/// Position in projective space
		SPC_POSITION_PROJECTIVE_SPACE,

		/// Position in light space index 0-7
		SPC_POSITION_LIGHT_SPACE0,
		SPC_POSITION_LIGHT_SPACE1,
		SPC_POSITION_LIGHT_SPACE2,
		SPC_POSITION_LIGHT_SPACE3,
		SPC_POSITION_LIGHT_SPACE4,
		SPC_POSITION_LIGHT_SPACE5,
		SPC_POSITION_LIGHT_SPACE6,
		SPC_POSITION_LIGHT_SPACE7,

		/// Normal in object space
		SPC_NORMAL_OBJECT_SPACE,

		/// Normal in world space
		SPC_NORMAL_WORLD_SPACE,

		/// Normal in view space
		SPC_NORMAL_VIEW_SPACE,

		/// Normal in tangent space
		SPC_NORMAL_TANGENT_SPACE,

		/// View vector in object space
		SPC_POSTOCAMERA_OBJECT_SPACE,

		/// View vector in world space
		SPC_POSTOCAMERA_WORLD_SPACE,

		/// View vector in view space
		SPC_POSTOCAMERA_VIEW_SPACE,

		/// View vector in tangent space
		SPC_POSTOCAMERA_TANGENT_SPACE,

		/// Light vector in object space index 0-7
		SPC_POSTOLIGHT_OBJECT_SPACE0,
		SPC_POSTOLIGHT_OBJECT_SPACE1,
		SPC_POSTOLIGHT_OBJECT_SPACE2,
		SPC_POSTOLIGHT_OBJECT_SPACE3,
		SPC_POSTOLIGHT_OBJECT_SPACE4,
		SPC_POSTOLIGHT_OBJECT_SPACE5,
		SPC_POSTOLIGHT_OBJECT_SPACE6,
		SPC_POSTOLIGHT_OBJECT_SPACE7,

		/// Light vector in world space index 0-7
		SPC_POSTOLIGHT_WORLD_SPACE0,
		SPC_POSTOLIGHT_WORLD_SPACE1,
		SPC_POSTOLIGHT_WORLD_SPACE2,
		SPC_POSTOLIGHT_WORLD_SPACE3,
		SPC_POSTOLIGHT_WORLD_SPACE4,
		SPC_POSTOLIGHT_WORLD_SPACE5,
		SPC_POSTOLIGHT_WORLD_SPACE6,
		SPC_POSTOLIGHT_WORLD_SPACE7,

		/// Light vector in view space index 0-7
		SPC_POSTOLIGHT_VIEW_SPACE0,
		SPC_POSTOLIGHT_VIEW_SPACE1,
		SPC_POSTOLIGHT_VIEW_SPACE2,
		SPC_POSTOLIGHT_VIEW_SPACE3,
		SPC_POSTOLIGHT_VIEW_SPACE4,
		SPC_POSTOLIGHT_VIEW_SPACE5,
		SPC_POSTOLIGHT_VIEW_SPACE6,
		SPC_POSTOLIGHT_VIEW_SPACE7,

		/// Light vector in tangent space index 0-7
		SPC_POSTOLIGHT_TANGENT_SPACE0,
		SPC_POSTOLIGHT_TANGENT_SPACE1,
		SPC_POSTOLIGHT_TANGENT_SPACE2,
		SPC_POSTOLIGHT_TANGENT_SPACE3,
		SPC_POSTOLIGHT_TANGENT_SPACE4,
		SPC_POSTOLIGHT_TANGENT_SPACE5,
		SPC_POSTOLIGHT_TANGENT_SPACE6,
		SPC_POSTOLIGHT_TANGENT_SPACE7,

		/// Light direction in object space index 0-7
		SPC_LIGHTDIRECTION_OBJECT_SPACE0,
		SPC_LIGHTDIRECTION_OBJECT_SPACE1,
		SPC_LIGHTDIRECTION_OBJECT_SPACE2,
		SPC_LIGHTDIRECTION_OBJECT_SPACE3,
		SPC_LIGHTDIRECTION_OBJECT_SPACE4,
		SPC_LIGHTDIRECTION_OBJECT_SPACE5,
		SPC_LIGHTDIRECTION_OBJECT_SPACE6,
		SPC_LIGHTDIRECTION_OBJECT_SPACE7,

		/// Light direction in world space index 0-7
		SPC_LIGHTDIRECTION_WORLD_SPACE0,
		SPC_LIGHTDIRECTION_WORLD_SPACE1,
		SPC_LIGHTDIRECTION_WORLD_SPACE2,
		SPC_LIGHTDIRECTION_WORLD_SPACE3,
		SPC_LIGHTDIRECTION_WORLD_SPACE4,
		SPC_LIGHTDIRECTION_WORLD_SPACE5,
		SPC_LIGHTDIRECTION_WORLD_SPACE6,
		SPC_LIGHTDIRECTION_WORLD_SPACE7,

		/// Light direction in view space index 0-7
		SPC_LIGHTDIRECTION_VIEW_SPACE0,
		SPC_LIGHTDIRECTION_VIEW_SPACE1,
		SPC_LIGHTDIRECTION_VIEW_SPACE2,
		SPC_LIGHTDIRECTION_VIEW_SPACE3,
		SPC_LIGHTDIRECTION_VIEW_SPACE4,
		SPC_LIGHTDIRECTION_VIEW_SPACE5,
		SPC_LIGHTDIRECTION_VIEW_SPACE6,
		SPC_LIGHTDIRECTION_VIEW_SPACE7,

		/// Light direction in tangent space index 0-7
		SPC_LIGHTDIRECTION_TANGENT_SPACE0,
		SPC_LIGHTDIRECTION_TANGENT_SPACE1,
		SPC_LIGHTDIRECTION_TANGENT_SPACE2,
		SPC_LIGHTDIRECTION_TANGENT_SPACE3,
		SPC_LIGHTDIRECTION_TANGENT_SPACE4,
		SPC_LIGHTDIRECTION_TANGENT_SPACE5,
		SPC_LIGHTDIRECTION_TANGENT_SPACE6,
		SPC_LIGHTDIRECTION_TANGENT_SPACE7,

		/// Light position in object space index 0-7
		SPC_LIGHTPOSITION_OBJECT_SPACE0,
		SPC_LIGHTPOSITION_OBJECT_SPACE1,
		SPC_LIGHTPOSITION_OBJECT_SPACE2,
		SPC_LIGHTPOSITION_OBJECT_SPACE3,
		SPC_LIGHTPOSITION_OBJECT_SPACE4,
		SPC_LIGHTPOSITION_OBJECT_SPACE5,
		SPC_LIGHTPOSITION_OBJECT_SPACE6,
		SPC_LIGHTPOSITION_OBJECT_SPACE7,

		/// Light position in world space index 0-7
		SPC_LIGHTPOSITION_WORLD_SPACE0,
		SPC_LIGHTPOSITION_WORLD_SPACE1,
		SPC_LIGHTPOSITION_WORLD_SPACE2,
		SPC_LIGHTPOSITION_WORLD_SPACE3,
		SPC_LIGHTPOSITION_WORLD_SPACE4,
		SPC_LIGHTPOSITION_WORLD_SPACE5,
		SPC_LIGHTPOSITION_WORLD_SPACE6,
		SPC_LIGHTPOSITION_WORLD_SPACE7,

		/// Light position in view space index 0-7
		SPC_LIGHTPOSITIONVIEW_SPACE0,
		SPC_LIGHTPOSITIONVIEW_SPACE1,
		SPC_LIGHTPOSITIONVIEW_SPACE2,
		SPC_LIGHTPOSITIONVIEW_SPACE3,
		SPC_LIGHTPOSITIONVIEW_SPACE4,
		SPC_LIGHTPOSITIONVIEW_SPACE5,
		SPC_LIGHTPOSITIONVIEW_SPACE6,
		SPC_LIGHTPOSITIONVIEW_SPACE7,

		/// Light position in tangent space index 0-7
		SPC_LIGHTPOSITION_TANGENT_SPACE,

		/// Blending weights
		SPC_BLEND_WEIGHTS,

		/// Blending indices
		SPC_BLEND_INDICES,
		
		/// Tangent in object space
		SPC_TANGENT_OBJECT_SPACE,

		/// Tangent in world space
		SPC_TANGENT_WORLD_SPACE,

		/// Tangent in view space
		SPC_TANGENT_VIEW_SPACE,

		/// Tangent in tangent space
		SPC_TANGENT_TANGENT_SPACE,

		/// Binormal in object space
		SPC_BINORMAL_OBJECT_SPACE,

		/// Binormal in world space
		SPC_BINORMAL_WORLD_SPACE,

		/// Binormal in view space
		SPC_BINORMAL_VIEW_SPACE,

		/// Binormal in tangent space
		SPC_BINORMAL_TANGENT_SPACE,

		/// Diffuse color
		SPC_COLOR_DIFFUSE,

		/// Specular color
		SPC_COLOR_SPECULAR,

		/// Depth in object space
		SPC_DEPTH_OBJECT_SPACE,

		/// Depth in world space
		SPC_DEPTH_WORLD_SPACE,

		/// Depth in view space
		SPC_DEPTH_VIEW_SPACE,

		/// Depth in projective space
		SPC_DEPTH_PROJECTIVE_SPACE,

		/// Texture coordinate set index 0-7
		SPC_TEXTURE_COORDINATE0,		
		SPC_TEXTURE_COORDINATE1,		
		SPC_TEXTURE_COORDINATE2,		
		SPC_TEXTURE_COORDINATE3,	
		SPC_TEXTURE_COORDINATE4,
		SPC_TEXTURE_COORDINATE5,
		SPC_TEXTURE_COORDINATE6,
		SPC_TEXTURE_COORDINATE7,

		/// Reserved custom content range to be used by user custom shader extensions.
		SPC_CUSTOM_CONTENT_BEGIN	= 1000,
		SPC_CUSTOM_CONTENT_END		= 2000
	};

// Interface.
public:
	/** */
	Parameter();

	/** Class constructor.
	@param type The type of this parameter.
	@param name The name of this parameter.
	@param semantic The semantic of this parameter.
	@param index The index of this parameter.
	@param content The content of this parameter.
	*/
	Parameter(GpuConstantType type, const String& name, 
		const Semantic& semantic, int index, 
		const Content& content, size_t size = 0);

	/** Class destructor */
	virtual ~Parameter() {};

	/** Get the name of this parameter. */
	const String& getName() const { return mName; }

	/** Get the type of this parameter. */
	GpuConstantType getType() const { return mType; }

	/** Get the semantic of this parameter. */
	const Semantic& getSemantic() const { return mSemantic; }

	/** Get the index of this parameter. */
	int getIndex() const { return mIndex; }	

	/** Return the content of this parameter. */
	Content getContent() const { return mContent; }

	/** Returns true if this instance is a ConstParameter otherwise false. */
	virtual bool isConstParameter() const { return false; }

	/** Returns the string representation of this parameter. */
	virtual String toString() const { return mName; }
	
	/** Returns Whether this parameter is an array. */
	bool isArray() const { return mSize > 0; }

	/** Returns the number of elements in the parameter (for arrays). */
	size_t getSize() const { return mSize; }
	
	/** Sets the number of elements in the parameter (for arrays). */
	void setSize(size_t size) { mSize = size; }

// Attributes.
protected:
	// Name of this parameter.
	String mName;
	// Type of this parameter.
	GpuConstantType mType;
	// Semantic of this parameter.
	Semantic mSemantic;
	// Index of this parameter.
	int mIndex;
	// The content of this parameter.
	Content mContent;
	// Number of elements in the parameter (for arrays)
	size_t mSize;
	
};

typedef SharedPtr<Parameter>					ParameterPtr; 
typedef vector<ParameterPtr>::type				ShaderParameterList;
typedef ShaderParameterList::iterator 			ShaderParameterIterator;
typedef ShaderParameterList::const_iterator		ShaderParameterConstIterator;

/** Uniform parameter class. Allow fast access to GPU parameter updates.
*/
class _OgreRTSSExport UniformParameter : public Parameter
{
public:

	/** Class constructor.
	@param type The type of this parameter.
	@param name The name of this parameter.
	@param semantic The semantic of this parameter.
	@param index The index of this parameter.
	@param content The content of this parameter.
	@param variability How this parameter varies (bitwise combination of GpuProgramVariability).
	@param size number of elements in the parameter.	
	*/
	UniformParameter(GpuConstantType type, const String& name, 
		const Semantic& semantic, int index, 
		const Content& content,
		uint16 variability, size_t size);

	/** Class constructor.
	@param autoType The auto type of this parameter.
	@param fAutoConstantData The real data for this auto constant parameter.	
	@param size number of elements in the parameter.	
	*/
	UniformParameter(GpuProgramParameters::AutoConstantType autoType, Real fAutoConstantData, size_t size);
	
	/** Class constructor.
	@param autoType The auto type of this parameter.
	@param fAutoConstantData The real data for this auto constant parameter.	
	@param size number of elements in the parameter.
	@param type The desired data type of this auto constant parameter.
	*/
	UniformParameter(GpuProgramParameters::AutoConstantType autoType, Real fAutoConstantData, size_t size, GpuConstantType type);

	/** Class constructor.
	@param autoType The auto type of this parameter.
	@param nAutoConstantData The int data for this auto constant parameter.	
	@param size number of elements in the parameter.	
	*/
	UniformParameter(GpuProgramParameters::AutoConstantType autoType, size_t nAutoConstantData, size_t size);
	
	/** Class constructor.
	@param autoType The auto type of this parameter.
	@param nAutoConstantData The int data for this auto constant parameter.	
	@param size number of elements in the parameter.
	@param type The desired data type of this auto constant parameter.
	*/
	UniformParameter(GpuProgramParameters::AutoConstantType autoType, size_t nAutoConstantData, size_t size, GpuConstantType type);

	
	/** Get auto constant int data of this parameter, in case it is auto constant parameter. */
	size_t getAutoConstantIntData() const { return mAutoConstantIntData; }	

	/** Get auto constant real data of this parameter, in case it is auto constant parameter. */
	Real getAutoConstantRealData() const { return mAutoConstantRealData; }	

	/** Return true if this parameter is a floating point type, false otherwise. */
	bool isFloat() const;

	/** Return true if this parameter is a texture sampler type, false otherwise. */
	bool isSampler() const;

	/** Return true if this parameter is an auto constant parameter, false otherwise. */
	bool isAutoConstantParameter() const { return mIsAutoConstantReal || mIsAutoConstantInt; }

	/** Return true if this parameter an auto constant with int data type, false otherwise. */
	bool isAutoConstantIntParameter() const { return mIsAutoConstantInt; }

	/** Return true if this parameter an auto constant with real data type, false otherwise. */
	bool isAutoConstantRealParameter() const { return mIsAutoConstantReal; }

	/** Return the auto constant type of this parameter. */
	GpuProgramParameters::AutoConstantType getAutoConstantType	() const { return mAutoConstantType; }

	/** Return the variability of this parameter. */
	uint16 getVariability() const { return mVariability; }

	/** Bind this parameter to the corresponding GPU parameter. */
	void bind(GpuProgramParametersSharedPtr paramsPtr);

public:

	/** Update the GPU parameter with the given value. */	
	void setGpuParameter(int val)
	{ 
		if (mParamsPtr != NULL)
		{
			mParamsPtr->_writeRawConstant(mPhysicalIndex, val);
		}
	}

	/** Update the GPU parameter with the given value. */	
	void setGpuParameter(Real val)  
	{ 
		if (mParamsPtr != NULL)
		{
			mParamsPtr->_writeRawConstant(mPhysicalIndex, val);
		}
	}

	/** Update the GPU parameter with the given value. */	
	void setGpuParameter(const ColourValue& val)  
	{ 
		if (mParamsPtr != NULL)
		{
			mParamsPtr->_writeRawConstant(mPhysicalIndex, val);
		}
	}

	/** Update the GPU parameter with the given value. */	
	void setGpuParameter(const Vector2& val)  
	{ 
		if (mParamsPtr != NULL)
		{
			mParamsPtr->_writeRawConstants(mPhysicalIndex, val.ptr(), 2);
		}
	}
	
	/** Update the GPU parameter with the given value. */	
	void setGpuParameter(const Vector3& val)  
	{ 
		if (mParamsPtr != NULL)
		{
			mParamsPtr->_writeRawConstant(mPhysicalIndex, val);
		}
	}

	/** Update the GPU parameter with the given value. */	
	void setGpuParameter(const Vector4& val)  
	{ 
		if (mParamsPtr != NULL)
		{
			mParamsPtr->_writeRawConstant(mPhysicalIndex, val);		
		}
	}

	/** Update the GPU parameter with the given value. */	
	void setGpuParameter(const Matrix4& val)  
	{ 
		if (mParamsPtr != NULL)
		{
			mParamsPtr->_writeRawConstant(mPhysicalIndex, val, 16);
		}
	}

	/** Update the GPU parameter with the given value. */	
	void setGpuParameter(const float *val, size_t count, size_t multiple = 4)  
	{ 
		if (mParamsPtr != NULL)
		{
			mParamsPtr->_writeRawConstants(mPhysicalIndex, val, count * multiple);
		}
	}

	/** Update the GPU parameter with the given value. */	
	void setGpuParameter(const double *val, size_t count, size_t multiple = 4)  
	{ 
		if (mParamsPtr != NULL)
		{
			mParamsPtr->_writeRawConstants(mPhysicalIndex, val, count * multiple);
		}
	}

	/** Update the GPU parameter with the given value. */	
	void setGpuParameter(const int *val, size_t count, size_t multiple = 4)  
	{ 
		if (mParamsPtr != NULL)
		{
			mParamsPtr->_writeRawConstants(mPhysicalIndex, val, count * multiple);
		}
	}

protected:
	// Is it auto constant real based parameter.
	bool mIsAutoConstantReal;
	// Is it auto constant int based parameter.
	bool mIsAutoConstantInt;
	GpuProgramParameters::AutoConstantType	mAutoConstantType;		// The auto constant type of this parameter.
	union
	{
		// Auto constant int data.
		size_t mAutoConstantIntData;
		// Auto constant real data.
		Real mAutoConstantRealData;
	};		
	// How this parameter varies (bitwise combination of GpuProgramVariability).
	uint16 mVariability;
	// The actual GPU parameters pointer.
	GpuProgramParameters* mParamsPtr;
	// The physical index of this parameter in the GPU program.
	size_t mPhysicalIndex;
};

typedef SharedPtr<UniformParameter>				UniformParameterPtr; 
typedef vector<UniformParameterPtr>::type		UniformParameterList;
typedef UniformParameterList::iterator 			UniformParameterIterator;
typedef UniformParameterList::const_iterator	UniformParameterConstIterator;

/** Helper template which is the base for our ConstParameters
*/
template <class valueType>
class ConstParameter : public Parameter
{
public:

	ConstParameter(	valueType val, 
		GpuConstantType type, 
		const Semantic& semantic,  
		const Content& content) 
		: Parameter(type, "Constant", semantic, 0, content)
	{
		mValue = val;
	}

	virtual				~ConstParameter		() {}

	/** Returns the native value of this parameter. (for example a Vector3) */
	const valueType& getValue() const { return mValue; }

	/** 
	@see Parameter::isConstParameter.
	*/
	virtual bool isConstParameter() const { return true; }

	/** 
	@see Parameter::toString.
	*/
	virtual String toString() const = 0;

protected:
	valueType mValue;
};

/** Helper utility class that creates common parameters.
*/
class _OgreRTSSExport ParameterFactory
{

	// Interface.
public:

	static ParameterPtr createInPosition(int index);	
	static ParameterPtr createOutPosition(int index);

	static ParameterPtr createInNormal(int index);
	static ParameterPtr createInWeights(int index);
	static ParameterPtr createInIndices(int index);
	static ParameterPtr createOutNormal(int index);
	static ParameterPtr createInBiNormal(int index);
	static ParameterPtr createOutBiNormal(int index);
	static ParameterPtr createInTangent(int index);
	static ParameterPtr createOutTangent(int index);
	static ParameterPtr createInColor(int index);
	static ParameterPtr createOutColor(int index);

	static ParameterPtr createInTexcoord(GpuConstantType type, int index, Parameter::Content content);
	static ParameterPtr createOutTexcoord(GpuConstantType type, int index, Parameter::Content content);
	static ParameterPtr createInTexcoord1(int index, Parameter::Content content);
	static ParameterPtr createOutTexcoord1(int index, Parameter::Content content);
	static ParameterPtr createInTexcoord2(int index, Parameter::Content content);
	static ParameterPtr createOutTexcoord2(int index, Parameter::Content content);
	static ParameterPtr createInTexcoord3(int index, Parameter::Content content);
	static ParameterPtr createOutTexcoord3(int index, Parameter::Content content);
	static ParameterPtr createInTexcoord4(int index, Parameter::Content content);			
	static ParameterPtr createOutTexcoord4(int index, Parameter::Content content);

	static ParameterPtr createConstParamVector2(Vector2 val);
	static ParameterPtr createConstParamVector3(Vector3 val);
	static ParameterPtr createConstParamVector4(Vector4 val);
	static ParameterPtr createConstParamFloat(float val);	

	static UniformParameterPtr createSampler(GpuConstantType type, int index);
	static UniformParameterPtr createSampler1D(int index);
	static UniformParameterPtr createSampler2D(int index);
	static UniformParameterPtr createSampler2DArray(int index);
	static UniformParameterPtr createSampler3D(int index);
	static UniformParameterPtr createSamplerCUBE(int index);	

	static UniformParameterPtr createUniform(GpuConstantType type, int index, uint16 variability, const String& suggestedName, size_t size);
};



/** @} */
/** @} */

}
}

#endif
