#include "ShaderProgram.h"
#include "Matrix4x4.h"
#include "Timer/PerfTimer.h"
#include "Vector3.h"
#include "Camera.h"
#include "Light.h"


using namespace std;

namespace CHCDemoEngine 
{ 

//////////
//-- changing shader parameters

static float sCurrentTimer = 0;
static Matrix4x4 sCurrentViewMatrix = IdentityMatrix();
static Vector3 sCurrentViewDir = Vector3::UNIT_Y();
static Vector3 sCurrentLightDir = Vector3::UNIT_Y();


/*********************************************************/
/*         GPUProgramParameters implementation           */
/*********************************************************/


GPUProgramParameters::GPUProgramParameters(ShaderProgram *p): 
mProgram(p), 
mTimerParam(-1),
mViewDirParam(-1),
mViewMatrixParam(-1),
mLightDirParam(-1)
{
}


GPUProgramParameters::GPUProgramParameters(): 
mProgram(NULL),
mTimerParam(-1),
mViewDirParam(-1),
mViewMatrixParam(-1),
mLightDirParam(-1)
{
}


void GPUProgramParameters::Reset()
{
	mFloats.clear();
	mTextures.clear();
	mMatrices.clear();
	mArrays.clear();

	mTimerParam = -1;
	mViewDirParam = -1;
	mLightDirParam = -1;
	mViewMatrixParam = -1;
}


void GPUProgramParameters::SetValue1f(int idx, float value)
{
	if (mFloats.size() < idx + 1)
		mFloats.resize(idx + 1);

	mFloats[idx] = FloatParam(&value, 1);
}


void GPUProgramParameters::SetValue2f(int idx, float val1, float val2)
{
	if (mFloats.size() < idx + 1)
		mFloats.resize(idx + 1);

	float vals[] = {val1, val2};

	mFloats[idx] = FloatParam(vals, 2);
}


void GPUProgramParameters::SetValue3f(int idx, float val1, float val2, float val3)
{
	if (mFloats.size() < idx + 1)
		mFloats.resize(idx + 1);

	float vals[] = {val1, val2, val3};

	mFloats[idx] = FloatParam(vals, 3);
}


void GPUProgramParameters::SetArray1f(int idx, float *vals, int numElements)
{
	if (mArrays.size() < idx + 1)
		mArrays.resize(idx + 1);

	mArrays[idx] = ArrayParam(vals, 1, numElements);
}


void GPUProgramParameters::SetArray2f(int idx, float *vals, int numElements)
{
	if (mArrays.size() < idx + 1)
		mArrays.resize(idx + 1);

	mArrays[idx] = ArrayParam(vals, 2, numElements);
}


void GPUProgramParameters::SetArray3f(int idx, float *vals, int numElements)
{
	if (mArrays.size() < idx + 1)
		mArrays.resize(idx + 1);

	mArrays[idx] = ArrayParam(vals, 3, numElements);
}


void GPUProgramParameters::SetTexture(int idx, unsigned int tex)
{
	if (mTextures.size() < idx + 1)
		mTextures.resize(idx + 1);

	mTextures[idx] = IntParam(tex);
}


void GPUProgramParameters::SetMatrix(int idx, Matrix4x4 *mat)
{
	if (mMatrices.size() < idx + 1)
		mMatrices.resize(idx + 1);

	mMatrices[idx] = MatrixParam(mat);
}


void GPUProgramParameters::SetTimerParam(int idx)
{
	mTimerParam = idx;
}


void GPUProgramParameters::SetViewMatrixParam(int idx)
{
	mViewMatrixParam = idx;
}


void GPUProgramParameters::SetViewDirParam(int idx)
{
	mViewDirParam = idx;
}


void GPUProgramParameters::SetLightDirParam(int idx)
{
	mLightDirParam = idx;
}


void GPUProgramParameters::SetValue1f(const string &name, float val)
{
	SetValue1f(mProgram->GetParamIdxByName(name), val);
}


void GPUProgramParameters::SetValue2f(const string &name, float val1, float val2)
{
	SetValue2f(mProgram->GetParamIdxByName(name), val1, val2);
}


void GPUProgramParameters::SetValue3f(const string &name, float val1, float val2, float val3)
{
	SetValue3f(mProgram->GetParamIdxByName(name), val1, val2, val3);
}


void GPUProgramParameters::SetArray1f(const string &name, float *vals, int numElements)
{
	SetArray1f(mProgram->GetParamIdxByName(name), vals, numElements);
}


void GPUProgramParameters::SetArray2f(const string &name, float *vals, int numElements)
{
	SetArray2f(mProgram->GetParamIdxByName(name), vals, numElements);
}


void GPUProgramParameters::SetArray3f(const string &name, float *vals, int numElements)
{
	SetArray3f(mProgram->GetParamIdxByName(name), vals, numElements);
}


void GPUProgramParameters::SetMatrix(const string &name, Matrix4x4 *mat)
{
	SetMatrix(mProgram->GetParamIdxByName(name), mat);
}


void GPUProgramParameters::SetTexture(const string &name, unsigned int tex)
{
	SetTexture(mProgram->GetParamIdxByName(name), tex);
}


void GPUProgramParameters::UpdateParameters()
{
	if (!mProgram) return;

	for (int i = 0; i < (int)mFloats.size(); ++ i)
	{
		const FloatParam &p = mFloats[i];

		if (!p.mValid) continue;

		switch (p.mNumComponents)
		{
		case 1:
			mProgram->SetValue1f(i, p.mValues[0]);
			break;
		case 2:
			mProgram->SetValue2f(i, p.mValues[0], p.mValues[1]);
			break;
		case 3:
			mProgram->SetValue3f(i, p.mValues[0], p.mValues[1], p.mValues[2]);
			break;
		default:
			mProgram->SetValue1f(i, p.mValues[0]);
		}
	}

	for (int i = 0; i < (int)mTextures.size(); ++ i)
	{
		const IntParam &p = mTextures[i];

		if (p.mValid)
			mProgram->SetTexture(i, p.mValue);
	}

	for (int i = 0; i < (int)mMatrices.size(); ++ i)
	{
		const MatrixParam &p = mMatrices[i];

		if (p.mValid)
			mProgram->SetMatrix(i, *p.mValue);
	}
	
	for (int i = 0; i < (int)mArrays.size(); ++ i)
	{
		const ArrayParam &p = mArrays[i];

		if (!p.mValid) continue;

		switch (p.mNumComponents)
		{
		case 1:
			mProgram->SetArray1f(i, p.mValues, p.mNumEntries);
			break;
		case 2:
			mProgram->SetArray2f(i, p.mValues, p.mNumEntries);
			break;
		case 3:
			mProgram->SetArray3f(i, p.mValues, p.mNumEntries);
			break;
		default:
			mProgram->SetArray1f(i, p.mValues, p.mNumEntries);
		}
	}

	if (mTimerParam >= 0)
		mProgram->SetValue1f(mTimerParam, sCurrentTimer);

	if (mViewDirParam >= 0)
		mProgram->SetValue3f(mViewDirParam, sCurrentViewDir.x, sCurrentViewDir.y, sCurrentViewDir.z);
	if (mLightDirParam >= 0)
		mProgram->SetValue3f(mLightDirParam, sCurrentLightDir.x, sCurrentLightDir.y, sCurrentLightDir.z);
	if (mViewMatrixParam >= 0)
		mProgram->SetMatrix(mViewMatrixParam, sCurrentViewMatrix);
}


void GPUProgramParameters::InitFrame(Camera *cam, DirectionalLight *light)
{
	static PerfTimer mytimer;
	sCurrentTimer = mytimer.Elapsedms(false) * M_PI / 180.0f;

	cam->GetModelViewMatrix(sCurrentViewMatrix);
	sCurrentViewDir = cam->GetDirection();

	Matrix4x4 vo;
	// transform to view space
	cam->GetViewOrientationMatrix(vo);
	//sCurrentLightDir = /*vo **/ -light->GetDirection();
	sCurrentLightDir = vo * -light->GetDirection();
}



/********************************************************/
/*             ShaderProgram implementation             */
/********************************************************/


ShaderProgram::ShaderProgram(CGcontext context, 
							 const std::string &filename, 
							 CGprofile profile,
							 const std::string &functionName)
{
	mProgram = cgCreateProgramFromFile(context, 
		                               CG_SOURCE,
									   filename.c_str(), 
									   profile,
									   functionName.c_str(),
									   NULL);

	if (mProgram) cgGLLoadProgram(mProgram);

	const int maxParams = 64;
	mParameters.resize(maxParams);

	for (int i = 0; i < maxParams; ++ i)
	{
		mParameters[i] = NULL;
	}
}


void ShaderProgram::Bind()
{
	cgGLBindProgram(mProgram);

	// enable all texture parameters
	CGParameterArray::const_iterator it, it_end = mTextureParams.end();

	for (it = mTextureParams.begin(); it != it_end; ++ it) 
		cgGLEnableTextureParameter(*it);
}


void ShaderProgram::Release()
{
	CGParameterArray::const_iterator it, it_end = mTextureParams.end();

	// disable all texture parameters
	for (it = mTextureParams.begin(); it != it_end; ++ it)
		cgGLDisableTextureParameter(*it);
}


CGparameter ShaderProgram::AddParameter(const string &name, int idx)
{
	CGparameter p = GetOrCreateParameter(name);

	mParamHash[name] = idx;
	mParameters[idx] = p;

	return p;
}


CGparameter ShaderProgram::GetOrCreateParameter(const string &name)
{
	CGparameter p;
	CGParameterMap::const_iterator it = mParamHash.find(name);

	if (it == mParamHash.end())
	{
		p = cgGetNamedParameter(mProgram, name.c_str());
	}
	else
	{
		p = mParameters[(*it).second];
	}

	//cout << "name: " << name << " " << p << " " << mProgram << endl;
	return p;
}


CGparameter ShaderProgram::GetParameter(int idx) const
{
	return mParameters[idx];
}


void ShaderProgram::SetValue1f(int idx, float val)
{
	cgGLSetParameter1f(GetParameter(idx), val);
}


void ShaderProgram::SetValue2f(int idx, float val1, float val2)
{
	cgGLSetParameter2f(GetParameter(idx), val1, val2);
}


void ShaderProgram::SetValue3f(int idx, float val1, float val2, float val3)
{
	cgGLSetParameter3f(GetParameter(idx), val1, val2, val3);
}


void ShaderProgram::SetArray1f(int idx, float *vals, int numElements)
{
	cgGLSetParameterArray1f(GetParameter(idx), 0, numElements, (const float *)vals);
}


void ShaderProgram::SetArray2f(int idx, float *vals, int numElements)
{
	cgGLSetParameterArray2f(GetParameter(idx), 0, numElements, (const float *)vals);
}


void ShaderProgram::SetArray3f(int idx, float *vals, int numElements)
{
	cgGLSetParameterArray3f(GetParameter(idx), 0, numElements, (const float *)vals);
}


void ShaderProgram::SetMatrix(int idx, const Matrix4x4 &mat)
{
	cgGLSetMatrixParameterfc(GetParameter(idx), (const float *)mat.x);
}


void ShaderProgram::SetTexture(int idx, unsigned int tex)
{
	CGparameter p = GetParameter(idx);

	cgGLSetTextureParameter(p, tex);
	cgGLEnableTextureParameter(p);
}


void ShaderProgram::SetValue1f(const string &name, float val)
{
	cgGLSetParameter1f(GetOrCreateParameter(name), val);
}


void ShaderProgram::SetValue2f(const string &name, float val1, float val2)
{
	cgGLSetParameter2f(GetOrCreateParameter(name), val1, val2);
}


void ShaderProgram::SetValue3f(const string &name, float val1, float val2, float val3)
{
	cgGLSetParameter3f(GetOrCreateParameter(name), val1, val2, val3);
}


void ShaderProgram::SetArray1f(const string &name, float *vals, int numElements)
{
	cgGLSetParameterArray1f(GetOrCreateParameter(name), 0, numElements, (const float *)vals);
}


void ShaderProgram::SetArray2f(const string &name, float *vals, int numElements)
{
	cgGLSetParameterArray2f(GetOrCreateParameter(name), 0, numElements, (const float *)vals);
}


void ShaderProgram::SetArray3f(const string &name, float *vals, int numElements)
{
	cgGLSetParameterArray3f(GetOrCreateParameter(name), 0, numElements, (const float *)vals);
}


void ShaderProgram::SetMatrix(const string &name, const Matrix4x4 &mat)
{
	cgGLSetMatrixParameterfc(GetOrCreateParameter(name), (const float *)mat.x);
}


void ShaderProgram::SetTexture(const string &name, unsigned int tex)
{
	CGparameter p = GetOrCreateParameter(name);

	cgGLSetTextureParameter(p, tex);
	cgGLEnableTextureParameter(p);

	mTextureParams.push_back(p);
}


int ShaderProgram::GetParamIdxByName(const std::string &name) const
{
	CGParameterMap::const_iterator it = mParamHash.find(name);
	return (*it).second;
}


} // namespace