//
// Copyright 2011 Jeff Lamarche
//
// Redistribution and use in source and binary forms, with or without modification, are permitted provided
// that the following conditions are met:
//	1. Redistributions of source code must retain the above copyright notice, this list of conditions and
//		the following disclaimer.
//
//	2. Redistributions in binary form must reproduce the above copyright notice, this list of conditions
//		and the following disclaimer in the documentation and/or other materials provided with the
//		distribution.
//
//	THIS SOFTWARE IS PROVIDED BY THE FREEBSD PROJECT ``AS IS'' AND ANY EXPRESS OR IMPLIED
//	WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
//	FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FREEBSD PROJECT
//	OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
//	CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
//	OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
//	AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
//	NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
//	ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
//
//
// Adapted for cocos2d http://www.cocos2d-iphone.org

#ifndef __CCGLPROGRAM_H__
#define __CCGLPROGRAM_H__

#include "ccMacros.h"
#include "CCObject.h"

NS_CC_BEGIN

enum {
	kCCVertexAttrib_Position,
	kCCVertexAttrib_Color,
	kCCVertexAttrib_TexCoords,

	kCCVertexAttrib_MAX,
};

enum {
	kCCUniformMVPMatrix,
	kCCUniformSampler,

	kCCUniform_MAX,
};

#define kCCShader_PositionTextureColor			"ShaderPositionTextureColor"
#define kCCShader_PositionTextureColorAlphaTest	"ShaderPositionTextureColorAlphaTest"
#define kCCShader_PositionColor					"ShaderPositionColor"
#define kCCShader_PositionTexture				"ShaderPositionTexture"
#define kCCShader_PositionTexture_uColor		"ShaderPositionTexture_uColor"
#define kCCShader_PositionTextureA8Color		"ShaderPositionTextureA8Color"

// uniform names
#define kCCUniformMVPMatrix_s			"u_MVPMatrix"
#define kCCUniformSampler_s				"u_texture"
#define kCCUniformAlphaTestValue		"u_alpha_value"

// Attribute names
#define	kCCAttributeNameColor			"a_color"
#define	kCCAttributeNamePosition		"a_position"
#define	kCCAttributeNameTexCoord		"a_texCoord"

typedef void (*GLInfoFunction)(GLuint program,
							   GLenum pname,
							   GLint* params);
typedef void (*GLLogFunction) (GLuint program,
							   GLsizei bufsize,
							   GLsizei* length,
							   GLchar* infolog);

/** CCGLProgram
 Class that implements a glProgram
 */
class CCGLProgram : public CCObject
{
public:
	CCGLProgram();
	virtual ~CCGLProgram();
	bool initWithVertexShaderFilename(const char* vShaderFilename, const char* fShaderFilename);
	void addAttribute(const char* attributeName, GLuint index);
	bool link();
	void use();
/* It will create 3 uniforms:
	- kCCUniformPMatrix
	- kCCUniformMVMatrix
	- kCCUniformSampler

 And it will bind "kCCUniformSampler" to 0

 @since v2.0.0
 */
	void updateUniforms();

	const char* vertexShaderLog();
	const char* fragmentShaderLog();
	const char* programLog();

private:
	const char* description();
	bool compileShader(GLuint * shader, GLenum type, const char* file);
	const char* logForOpenGLObject(GLuint object, GLInfoFunction infoFunc, GLLogFunction logFunc);

public:
	GLuint          program_;
	GLuint			vertShader_;
	GLuint			fragShader_;
	GLint			uniforms_[kCCUniform_MAX];
};

NS_CC_END

#endif /* __CCGLPROGRAM_H__ */