#include "glInterface.h"
#include "GlobalLinesRenderer.h"
#include "common.h"
#include "RenderTexture.h"
#include "Preprocessor.h"
#include "GlRenderer.h"
// the devil library
#include <IL/il.h>
#include <IL/ilu.h>
#include <IL/ilut.h>

#include <Cg/cg.h>
#include <Cg/cgGL.h>

//#include <QtOpenGL>

namespace GtpVisibilityPreprocessor {


static CGcontext sCgContext = NULL;
static CGprogram sCgDepthPeelingProgram = NULL;
static CGprogram sCgPassThroughProgram = NULL;

static CGprofile sCgFragmentProfile;
static CGparameter sTextureParam;

GlobalLinesRenderer *globalLinesRenderer = NULL;

static int texWidth = 256;
static int texHeight = 256;


static void InitDevIl()
{
	ilInit();
	ILuint ImageName;
	ilGenImages(1, &ImageName);
	ilBindImage(ImageName);
	ilEnable(IL_FILE_OVERWRITE);

	//  ilRegisterFormat(IL_RGBA);
	//  ilRegisterType(IL_FLOAT);

	//  ilEnable(IL_ORIGIN_SET);
	//  ilOriginFunc(IL_ORIGIN_UPPER_LEFT);
}


static void cgErrorCallback()
{
	CGerror lastError = cgGetError();

	if(lastError)
	{
		printf("%s\n\n", cgGetErrorString(lastError));
		printf("%s\n", cgGetLastListing(sCgContext));
		printf("Cg error, exiting...\n");

		exit(0);
	}
}

static void PrintGLerror(char *msg)
{
	GLenum errCode;
	const GLubyte *errStr;
	
	if ((errCode = glGetError()) != GL_NO_ERROR) 
	{
		errStr = gluErrorString(errCode);
		fprintf(stderr,"OpenGL ERROR: %s: %s\n", errStr, msg);
	}
}


void Reshape(int w, int h)
{
	if (h == 0) h = 1;

	glViewport(0, 0, w, h);

	glMatrixMode(GL_PROJECTION);
	glLoadIdentity();

	//gluPerspective(60.0, (GLfloat)w/(GLfloat)h, 3, 5000.0);
	//gluPerspective(60.0, (GLfloat)w/(GLfloat)h, 0.5, 10.0);
	glOrtho(-1, 1, -1, 1, 0.5, 15);
}


void SetFrustum(int sizeX, int sizeY, float nearPlane, float farPlane)
{
	glMatrixMode(GL_PROJECTION);
	glLoadIdentity();

	glOrtho(-sizeX / 2, sizeX / 2, 
			-sizeY / 2, sizeY / 2, 
			nearPlane, farPlane);

	/*glOrtho(0, sizeX, 
		    0, sizeY , 
			nearPlane, farPlane);*/
}

void Display()
{
	//globalLinesRenderer->DrawGeometry();
	globalLinesRenderer->CastGlobalLines(Beam(), 0);
	PrintGLerror("display");

	glutSwapBuffers();
}


void Idle()
{
	glutPostRedisplay();
}


void Keyboard(unsigned char key, int x, int y)
{
	switch(key)
	{
	case '2':
		++ globalLinesRenderer->mMaxDepth;
		cout << "max depth: " << globalLinesRenderer->mMaxDepth << endl;
		return;
	case '1':
		-- globalLinesRenderer->mMaxDepth;
		cout << "max depth: " << globalLinesRenderer->mMaxDepth << endl;
		return;
	case '3':
		//globalLinesRenderer->ApplyDepthPeeling(Beam(), 0);
		globalLinesRenderer->GrabDepthBuffer(globalLinesRenderer->mNewDepthBuffer, globalLinesRenderer->mNewTexture);
	default:
		return;
	}
}


/*GlobalLinesRenderer::GlobalLinesRenderer(RenderTexture *buffer1, 
										 RenderTexture *buffer2, 
										 Preprocessor *preprocessor,
										 GlRenderer *renderer)
: mNewTexture(buffer1), mOldTexture(buffer2), mPreprocessor(preprocessor), mMaxDepth(100),
mRenderer(renderer)
{
}
*/


GlobalLinesRenderer::GlobalLinesRenderer(Preprocessor *preprocessor, 
										 GlRenderer *renderer): 
mNewTexture(NULL), 
mOldTexture(NULL), 
mMaxDepth(0), 
mRenderer(renderer), 
mPreprocessor(preprocessor)
{
}


GlobalLinesRenderer::~GlobalLinesRenderer()
{
	if (sCgDepthPeelingProgram)
		cgDestroyProgram(sCgDepthPeelingProgram);
	if (sCgContext)
		cgDestroyContext(sCgContext);
}

 
void GlobalLinesRenderer::CastGlobalLines(Beam &beam, const int samples)
{
	// bind pixel shader implementing the front depth buffer functionality
	ApplyDepthPeeling(beam, samples);
}


void GlobalLinesRenderer::RenderObject(Intersectable *obj)
{
	mRenderer->RenderIntersectable(obj);
}


void GlobalLinesRenderer::DrawGeometry()
{ 
	glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
	glMatrixMode(GL_MODELVIEW);

	glPushMatrix();
	{ 
		//glLoadIdentity();
			
		//mRenderer->mUseFalseColors = true;
		ObjectContainer::const_iterator oit, oit_end = mPreprocessor->mObjects.end();

		Intersectable::NewMail();

		for (oit = mPreprocessor->mObjects.begin(); oit != oit_end; ++ oit)
		{
			RenderObject(*oit);
		}
	}
	glPopMatrix();
}


void GlobalLinesRenderer::SwitchRenderTextures()
{
	RenderTexture *buffer = mOldTexture;
	mOldTexture = mNewTexture;
	mNewTexture = buffer;
}


void GlobalLinesRenderer::InitGl()
{
	InitDevIl();

	glutInitDisplayMode(GLUT_RGB | GLUT_DEPTH | GLUT_DOUBLE);
	glutInitWindowPosition(50, 50);
	glutInitWindowSize(512, 512);
	glutCreateWindow("TestRenderDepthTexture");  

	int err = glewInit();
	if (GLEW_OK != err)
	{
		// problem: glewInit failed, something is seriously wrong
		fprintf(stderr, "GLEW Error: %s\n", glewGetErrorString(err));
		exit(-1);
	}  
	
	glutKeyboardFunc(Keyboard);
	glutDisplayFunc(Display);
	glutIdleFunc(Idle);
	glutReshapeFunc(Reshape);

	Reshape(512, 512);
	glMatrixMode(GL_MODELVIEW);
	glLoadIdentity();

	AxisAlignedBox3 bbox = globalLinesRenderer->mPreprocessor->mKdTree->GetBox();
	
	Vector3 midPoint = bbox.Center();
	
	const float sceneSize = Magnitude(bbox.Diagonal());
	Vector3 viewPoint = midPoint + Vector3(0.5 * sceneSize, 0, 0);
	
	cout << "mid point: " << midPoint << endl;
	cout << "view point: " << viewPoint << endl;
	cout << "scene: " << bbox << endl;

	/*gluLookAt(viewPoint.x, viewPoint.y, viewPoint.z, 
			  midPoint.x, midPoint.y, midPoint.z, 
			  0, 1, 0);
*/
	gluLookAt(0, 0, 3, 0, 0, 0, 0, 1, 0);

	//glDisable(GL_CULL_FACE);
	glEnable(GL_CULL_FACE);
	glDisable(GL_LIGHTING);
	glDisable(GL_COLOR_MATERIAL);
	glEnable(GL_DEPTH_TEST); 
	glClearColor(0.1, 0.2, 0.3, 1);
	
	// A square, mipmapped, anisotropically filtered 8-bit RGBA texture with
	// depth and stencil.
	// Note that RT_COPY_TO_TEXTURE is required for depth textures on ATI hardware
	
	mNewTexture = new RenderTexture(texWidth, texHeight, true, true);
	//mNewTexture->Initialize(true, true, false, true, true, 8, 8, 8, 8);//, RenderTexture::RT_COPY_TO_TEXTURE);
	mNewTexture->Initialize(true, true, false, true, true, 8, 8, 8, 8, RenderTexture::RT_COPY_TO_TEXTURE);
	
	mOldTexture = new RenderTexture(texWidth, texHeight, true, true);
	//mOldTexture ->Initialize(true, true, false, true, true, 8, 8, 8, 8);//, RenderTexture::RT_COPY_TO_TEXTURE);
	mOldTexture ->Initialize(true, true, false, true, true, 8, 8, 8, 8, RenderTexture::RT_COPY_TO_TEXTURE);

	// Setup Cg
	cgSetErrorCallback(cgErrorCallback);

	// Create cgContext.
	sCgContext = cgCreateContext();

	// get the best profile for this hardware
	sCgFragmentProfile = cgGLGetLatestProfile(CG_GL_FRAGMENT);
	
	//assert(sCgFragmentProfile != CG_PROFILE_UNKNOWN);
	cgGLSetOptimalOptions(sCgFragmentProfile);

	sCgDepthPeelingProgram = 
		cgCreateProgramFromFile(sCgContext, 
								CG_SOURCE,
								mNewTexture->IsRectangleTexture() ? 
								"../src/depth_peelingRect.cg" : "../src/depth_peeling2d.cg", 
								GLEW_ARB_fragment_program ? CG_PROFILE_ARBFP1 : CG_PROFILE_FP30,
								NULL,
								NULL);

	if(sCgDepthPeelingProgram != NULL)
	{
		cgGLLoadProgram(sCgDepthPeelingProgram);
		sTextureParam = cgGetNamedParameter(sCgDepthPeelingProgram, "depthTex");  
	}

	sCgPassThroughProgram = 
		cgCreateProgramFromFile(sCgContext, 
								CG_SOURCE,
								"../src/passthrough.cg", 
								GLEW_ARB_fragment_program ? CG_PROFILE_ARBFP1 : CG_PROFILE_FP30,
								NULL,
								NULL);

	if(sCgPassThroughProgram != NULL)
	{
		cgGLLoadProgram(sCgPassThroughProgram);
	}

    // setup the rendering context for the RenderTexture
	mNewTexture->BeginCapture();
	{
		//Reshape(texWidth, texHeight);
		glViewport(0, 0, texWidth, texHeight);
		SetFrustum(sceneSize, sceneSize, 1, sceneSize);

		glClearColor(0.1, 0.7, 0.2, 1);
		glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

		glFrontFace(GL_CCW);
		glCullFace(GL_BACK);
		glEnable(GL_CULL_FACE);
		glShadeModel(GL_FLAT);
		glEnable(GL_DEPTH_TEST);
		
		glMatrixMode(GL_MODELVIEW);
		glLoadIdentity();
		gluLookAt(viewPoint.x, viewPoint.y, viewPoint.z, 
				  midPoint.x, midPoint.y, midPoint.z, 
				  0, 1, 0);

		//SetFrustum(sceneSize, sceneSize, 1, sceneSize);
	}
	mNewTexture->EndCapture();

	// setup the rendering context for the RenderTexture
	mOldTexture->BeginCapture();
	{
		glClearColor(0.1, 0.7, 0.2, 1);
       
		//Reshape(texWidth, texHeight);
		glViewport(0, 0, texWidth, texHeight);
		SetFrustum(sceneSize, sceneSize, 1, sceneSize);

		glMatrixMode(GL_MODELVIEW);
		glLoadIdentity();
		
		glFrontFace(GL_CCW);
		glCullFace(GL_BACK);
		glEnable(GL_CULL_FACE);
		glShadeModel(GL_FLAT);
		glEnable(GL_DEPTH_TEST);
		
		gluLookAt(viewPoint.x, viewPoint.y, viewPoint.z, 
				  midPoint.x, midPoint.y, midPoint.z, 
				  0, 1, 0);

		//SetFrustum(sceneSize, sceneSize, 1, sceneSize);
	}
	mOldTexture->EndCapture();

	PrintGLerror("init");
}


Intersectable *GetObject(const int index)
{
	return NULL;
}


void GlobalLinesRenderer::ProcessDepthBuffer(VssRayContainer &vssRays)
{
	GrabDepthBuffer(mNewDepthBuffer, mNewTexture);
	GrabDepthBuffer(mOldDepthBuffer, mOldTexture);

	GrabItemBuffer(mNewItemBuffer, mNewTexture);
	GrabItemBuffer(mOldItemBuffer, mOldTexture);

	for (int y = 0; y < texHeight; ++ y)
	{
		for (int x = 0; x < texWidth; ++ x)
		{
			const int index = x + texWidth * y;
			const float newDepth = mNewDepthBuffer[index];
			const float oldDepth = mOldDepthBuffer[index];

			float newDummy1 = mNear + (mFar - mNear) * newDepth;
			float oldDummy1 = mNear + (mFar - mNear) * oldDepth;

			float newDummy2 = x - texWidth / 2;
			float newDummy3 = y -  texHeight / 2;

			float oldDummy2 = newDummy2;
			float oldDummy3 = newDummy3;

			const Vector3 newPt = newDepth * mEyeVec + newDummy1 * mLeftVec + newDummy2 * mUpVec;
			const Vector3 oldPt = oldDepth * mEyeVec + oldDummy1 * mLeftVec + oldDummy2 * mUpVec;

			Intersectable *termObj1 = GetObject(mNewItemBuffer[index]);
			Intersectable *termObj2 = GetObject(mOldItemBuffer[index]);

			// create rays in both directions
			vssRays.push_back(new VssRay(oldPt, newPt, NULL, termObj1));
			vssRays.push_back(new VssRay(newPt, oldPt, NULL, termObj2));
		}
	}
}


void GlobalLinesRenderer::Run()
{
	glutMainLoop();
}


void GlobalLinesRenderer::GrabDepthBuffer(float *data, RenderTexture *rt)
{
	rt->BindDepth();
	rt->EnableTextureTarget();
	cout << "depth: " << mNewTexture->GetDepthBits() << endl;

	const int texFormat = GL_DEPTH_COMPONENT;
	glGetTexImage(mNewTexture->GetTextureTarget(), 0, texFormat, GL_FLOAT, data);

	mNewTexture->DisableTextureTarget();
}


void GlobalLinesRenderer::GrabItemBuffer(float *data, RenderTexture *rt)
{
	rt->BindDepth();
	rt->EnableTextureTarget();
	cout << "depth: " << mNewTexture->GetDepthBits() << endl;

	const int texFormat = GL_DEPTH_COMPONENT;
	glGetTexImage(mNewTexture->GetTextureTarget(), 0, texFormat, GL_FLOAT, data);

	mNewTexture->DisableTextureTarget();
}

void GlobalLinesRenderer::ExportDepthBuffer()
{
	mNewTexture->BindDepth();
	mNewTexture->EnableTextureTarget();
	cout << "depth: " << mNewTexture->GetDepthBits() << endl;

	const bool components = 1;//mNewTexture->GetDepthBits() / 8;

	float *data = new float[texWidth * texHeight * components];
	//const int texFormat = WGL_TEXTURE_DEPTH_COMPONENT_NV;
	const int texFormat = GL_DEPTH_COMPONENT;
	//const int texFormat = GL_RGBA;
	glGetTexImage(mNewTexture->GetTextureTarget(), 0, texFormat, GL_FLOAT, data);

	/*for (int i = texWidth * 123; i < texWidth * 124; ++ i)
	{
		cout << data[i] << " ";
	}
	cout << "Saving image " << texWidth << " " << texHeight << endl;
*/
	string filename("depth.tga");
	ilRegisterType(IL_FLOAT);

	const int depth = 1;
	const int bpp = components;

	ilTexImage(texWidth, texHeight, depth, bpp, IL_LUMINANCE, IL_FLOAT, data);
	ilSaveImage((char *const)filename.c_str());

	cout << "finished" << endl;
	delete data;
	cout << "data deleted" << endl;
	mNewTexture->DisableTextureTarget();
	PrintGLerror("grab texture");
}


void GlobalLinesRenderer::ApplyDepthPeeling(Beam &beam, const int samples)
{
	mNewTexture->BeginCapture();
	{
		//cgGLBindProgram(sCgPassThroughProgram);
		//cgGLEnableProfile(sCgFragmentProfile);
		DrawGeometry();
	}
	mNewTexture->EndCapture();
	
	PrintGLerror("firstpass");

	if (mNewTexture->IsRectangleTexture()) cout << "rect" << endl;

	for(int i = 0; i < mMaxDepth; ++ i) 
	{
		// Peel another layer
		SwitchRenderTextures(); // switch pointer between rendertextures

		mNewTexture->BeginCapture();
		{
			//if (mNewTexture->IsDoubleBuffered()) 
			//	glDrawBuffer(GL_BACK);

			glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);         

			cgGLBindProgram(sCgDepthPeelingProgram);
		//	cgGLBindProgram(sCgPassThroughProgram);
			cgGLEnableProfile(sCgFragmentProfile);
			cgGLSetTextureParameter(sTextureParam, mOldTexture->GetDepthTextureID());
			cgGLEnableTextureParameter(sTextureParam);

			//glutSolidTorus(0.25, 1, 32, 64);
			DrawGeometry();
			
			glPopMatrix();

			cgGLDisableTextureParameter(sTextureParam);
			cgGLDisableProfile(sCgFragmentProfile);
		}
		mNewTexture->EndCapture();
	}

	PrintGLerror("endpeeling");

	//mNewTexture->Bind();
	mNewTexture->BindDepth();
	mNewTexture->EnableTextureTarget();
	
	glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
	
	if (mNewTexture->IsRectangleTexture())
	{
		glBegin(GL_QUADS);
		glTexCoord2f(0, 0); glVertex3f(-1, -1, -0.5f);
		glTexCoord2f(mNewTexture->GetWidth(), 0); glVertex3f( 1, -1, -0.5f);
		glTexCoord2f(mNewTexture->GetWidth(), mNewTexture->GetHeight()); glVertex3f( 1,  1, -0.5f);
		glTexCoord2f(0, mNewTexture->GetHeight()); glVertex3f(-1, 1, -0.5f);
		glEnd();
	}
	else
	{
		glBegin(GL_QUADS);
		glTexCoord2f(0, 0); glVertex3f(-1, -1, -0.5f);
		glTexCoord2f(1, 0); glVertex3f( 1, -1, -0.5f);
		glTexCoord2f(1, 1); glVertex3f( 1,  1, -0.5f);
		glTexCoord2f(0, 1); glVertex3f(-1,  1, -0.5f);
		glEnd();
	}  

	mNewTexture->DisableTextureTarget();
	PrintGLerror("displaytexture");
}


}