#include "Mesh.h"
#include "glInterface.h"
#include "OcclusionQuery.h"
#include "GlRenderer.h"
#include "ViewCellsManager.h"
#include "SceneGraph.h"
#include "Pvs.h"
#include "Viewcell.h"
#include "Beam.h"
#include "KdTree.h"
#include "Environment.h"
#include "Triangle3.h"
#include "IntersectableWrapper.h"
#include "BvHierarchy.h"

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


namespace GtpVisibilityPreprocessor {


static bool arbQuerySupport = false;
static bool nvQuerySupport = false;


static void InitExtensions() 
{
	GLenum err = glewInit();

	if (GLEW_OK != err) 
	{
		// problem: glewInit failed, something is seriously wrong
		cerr << "Error: " << glewGetErrorString(err) << endl;
		exit(1);
	}

	if (GLEW_ARB_occlusion_query) 
		arbQuerySupport = true;
	
	if (GLEW_NV_occlusion_query) 
		nvQuerySupport = true;
	

	if  (!arbQuerySupport && !nvQuerySupport)
	{
		cout << "I require the GL_ARB_occlusion_query or the GL_NV_occlusion_query OpenGL extension to work.\n";
		exit(1);
	}
}


GlRenderer::GlRenderer(SceneGraph *sceneGraph,
					   ViewCellsManager *viewCellsManager,
					   KdTree *tree):
  Renderer(sceneGraph, viewCellsManager),
  mKdTree(tree)
{
  mSceneGraph->CollectObjects(&mObjects);

  //  mViewCellsManager->GetViewPoint(mViewPoint);

  mViewPoint = mSceneGraph->GetBox().Center();
  mViewDirection = Vector3(0,0,1);

  //  mViewPoint = Vector3(991.7, 187.8, -271);
  //  mViewDirection = Vector3(0.9, 0, -0.4);

  //  timerId = startTimer(10);
  // debug coords for atlanta
  //  mViewPoint = Vector3(3473, 6.778, -1699);
  //  mViewDirection = Vector3(-0.2432, 0, 0.97);
  
  mFrame = 0;
  mWireFrame = false;
  Environment::GetSingleton()->GetBoolValue("Preprocessor.detectEmptyViewSpace", mDetectEmptyViewSpace);
  mSnapErrorFrames = true;
  mSnapPrefix = "snap/";
  mUseForcedColors = false;

  mUseGlLists = true;
  //mUseGlLists = false;
}

GlRenderer::~GlRenderer()
{
  cerr<<"gl renderer destructor..\n";
 
  //CLEAR_CONTAINER(sQueries);
  CLEAR_CONTAINER(mOcclusionQueries);

  cerr<<"done."<<endl;
}


void
GlRenderer::RenderTriangle(TriangleIntersectable *object)
{
  Triangle3 &t = object->GetItem();
  glBegin(GL_TRIANGLES);
  glVertex3f(t.mVertices[0].x, t.mVertices[0].y, t.mVertices[0].z);
  glVertex3f(t.mVertices[1].x, t.mVertices[1].y, t.mVertices[1].z);
  glVertex3f(t.mVertices[2].x, t.mVertices[2].y, t.mVertices[2].z);
  glEnd();
}

void
GlRenderer::RenderIntersectable(Intersectable *object)
{

  glPushAttrib(GL_CURRENT_BIT);
  if (mUseFalseColors)
	SetupFalseColor(object->mId);
  

  switch (object->Type()) {
  case Intersectable::MESH_INSTANCE:
	RenderMeshInstance((MeshInstance *)object);
	break;
  case Intersectable::VIEW_CELL:
	RenderViewCell(dynamic_cast<ViewCell *>(object));
	break;
  case Intersectable::TRANSFORMED_MESH_INSTANCE:
	RenderTransformedMeshInstance(dynamic_cast<TransformedMeshInstance *>(object));
	break;
  case Intersectable::TRIANGLE_INTERSECTABLE:
	RenderTriangle(dynamic_cast<TriangleIntersectable *>(object));
	break;
  case Intersectable::BVH_INTERSECTABLE: {

	BvhNode *node = (dynamic_cast<BvhIntersectable *>(object))->GetItem();
	//	RenderBvhNode(node);
	RenderBox(node->GetBoundingBox());
	break;
  }
	
  default:
	cerr<<"Rendering this object not yet implemented\n";
	break;
  }

  glPopAttrib();
}

void
GlRenderer::RenderRays(const VssRayContainer &rays)
{
  VssRayContainer::const_iterator it = rays.begin(), it_end = rays.end();

  glBegin(GL_LINES);
  for (; it != it_end; ++it) {
	VssRay *ray = *it;
	float importance = log10(1e3*ray->mWeightedPvsContribution)/3.0f;
	//	cout<<"w="<<ray->mWeightedPvsContribution<<" r="<<ray->mWeightedPvsContribution;
	glColor3f(importance, importance, importance);
	glVertex3fv(&ray->mOrigin.x);
	glVertex3fv(&ray->mTermination.x);
  }
  glEnd();
}

void
GlRenderer::RenderViewCell(ViewCell *vc)
{
  if (vc->GetMesh()) {

	if (!mUseFalseColors) {
	  if (vc->GetValid()) 
		glColor3f(0,1,0);
	  else
		glColor3f(0,0,1);
	}
	
	RenderMesh(vc->GetMesh());
  } else {
	// render viewcells in the subtree
	if (!vc->IsLeaf()) {
	  ViewCellInterior *vci = (ViewCellInterior *) vc;

	  ViewCellContainer::iterator it = vci->mChildren.begin();
	  for (; it != vci->mChildren.end(); ++it) {
		RenderViewCell(*it);
	  }
	} else {
	  //	  cerr<<"Empty viewcell mesh\n";
	}
  }
}


void
GlRenderer::RenderMeshInstance(MeshInstance *mi)
{
  RenderMesh(mi->GetMesh());
}


void
GlRenderer::RenderTransformedMeshInstance(TransformedMeshInstance *mi)
{
	// apply world transform before rendering
	Matrix4x4 m;
	mi->GetWorldTransform(m);

	glPushMatrix();
/* cout << "\n";
	for (int i = 0; i < 4; ++ i)
		for (int j = 0; j < 4; ++ j)
			cout << m.x[i][j] << " "; cout << "\n"*/

	glMultMatrixf((float *)m.x);

	/*GLfloat dummy[16];
	glGetFloatv(GL_MODELVIEW_MATRIX, dummy);
	for (int i = 0; i < 16; ++ i)
		cout << dummy[i] << " ";
	cout << endl;*/
	RenderMesh(mi->GetMesh());
	
	glPopMatrix();
}


void
GlRenderer::SetupFalseColor(const int id)
{
  // swap bits of the color
  glColor3ub(id&255, (id>>8)&255, (id>>16)&255);
}


int GlRenderer::GetId(int r, int g, int b) const
{
	return r + (g << 8) + (b << 16);
}

void
GlRenderer::SetupMaterial(Material *m)
{
  if (m)
	glColor3fv(&(m->mDiffuseColor.r));
}

void
GlRenderer::RenderMesh(Mesh *mesh)
{
  int i = 0;

  if (!mUseFalseColors && !mUseForcedColors)
	SetupMaterial(mesh->mMaterial);
  
  for (i=0; i < mesh->mFaces.size(); i++) {
	if (mWireFrame)
	  glBegin(GL_LINE_LOOP);
	else
	  glBegin(GL_POLYGON);

	Face *face = mesh->mFaces[i];
	for (int j = 0; j < face->mVertexIndices.size(); j++) {
	  glVertex3fv(&mesh->mVertices[face->mVertexIndices[j]].x);
	}
	glEnd();
  }
}
	
void
GlRenderer::InitGL()
{
  glMatrixMode(GL_PROJECTION);
  glLoadIdentity();
  
  glMatrixMode(GL_MODELVIEW);
  glLoadIdentity();

  glEnable(GL_CULL_FACE);
  glShadeModel(GL_FLAT);
  glEnable(GL_DEPTH_TEST);
  glEnable(GL_CULL_FACE);
  
  InitExtensions();
  
#if 0
  GLfloat mat_ambient[]   = {  0.5, 0.5, 0.5, 1.0  };
  /*  mat_specular and mat_shininess are NOT default values	*/
  GLfloat mat_diffuse[]   = {  1.0, 1.0, 1.0, 1.0  };
  GLfloat mat_specular[]  = {  0.3, 0.3, 0.3, 1.0  };
  GLfloat mat_shininess[] = {  1.0  };
  
  GLfloat light_ambient[]  = {  0.2, 0.2, 0.2, 1.0  };
  GLfloat light_diffuse[]  = {  0.4, 0.4, 0.4, 1.0  };
  GLfloat light_specular[] = {  0.3, 0.3, 0.3, 1.0  };
  
  GLfloat lmodel_ambient[] = {  0.3, 0.3, 0.3, 1.0  };
  
  
  // default Material
  glMaterialfv(GL_FRONT, GL_AMBIENT, mat_ambient);
  glMaterialfv(GL_FRONT, GL_DIFFUSE, mat_diffuse);
  glMaterialfv(GL_FRONT, GL_SPECULAR, mat_specular);
  glMaterialfv(GL_FRONT, GL_SHININESS, mat_shininess);

  // a light
  glLightfv(GL_LIGHT0, GL_AMBIENT, light_ambient);
  glLightfv(GL_LIGHT0, GL_DIFFUSE, light_diffuse);
  glLightfv(GL_LIGHT0, GL_SPECULAR, light_specular);
  
  glLightfv(GL_LIGHT1, GL_AMBIENT, light_ambient);
  glLightfv(GL_LIGHT1, GL_DIFFUSE, light_diffuse);
  glLightfv(GL_LIGHT1, GL_SPECULAR, light_specular);
  
  glLightModelfv(GL_LIGHT_MODEL_AMBIENT, lmodel_ambient);
  
  glEnable(GL_LIGHTING);
  glEnable(GL_LIGHT0);
  glEnable(GL_LIGHT1);
  
  
  // set position of the light
  GLfloat infinite_light[] = {  1.0, 0.8, 1.0, 0.0  };
  glLightfv (GL_LIGHT0, GL_POSITION, infinite_light);
  
  // set position of the light2
  GLfloat infinite_light2[] = {  -0.3, 1.5, 1.0, 0.0  };
  glLightfv (GL_LIGHT1, GL_POSITION, infinite_light2);
  
  glColorMaterial( GL_FRONT_AND_BACK, GL_AMBIENT_AND_DIFFUSE);
  //   glColorMaterial( GL_FRONT_AND_BACK, GL_SPECULAR);
  glEnable(GL_COLOR_MATERIAL);
  
  glShadeModel( GL_FLAT );
  
  glDepthFunc( GL_LESS );
  glEnable( GL_DEPTH_TEST );
#endif

  glTexEnvi(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_REPLACE );

  glEnable( GL_NORMALIZE );
  
  glClearColor(0.0f, 0.0f, 1.0f, 1.0f);
}


void
GlRenderer::SetupProjection(const int w, const int h, const float angle)
{
  glViewport(0, 0, w, h);
  glMatrixMode(GL_PROJECTION);
  glLoadIdentity();
  gluPerspective(angle, 1.0, 0.1, 2.0*Magnitude(mSceneGraph->GetBox().Diagonal()));
  glMatrixMode(GL_MODELVIEW);
}



void
GlRenderer::SetupCamera()
{
  Vector3 target = mViewPoint + mViewDirection;

  Vector3 up(0,1,0);
  
  if (abs(DotProd(mViewDirection, up)) > 0.99f)
	up = Vector3(1, 0, 0);
  
  glLoadIdentity();
  gluLookAt(mViewPoint.x, mViewPoint.y, mViewPoint.z,
			target.x, target.y, target.z,
			up.x, up.y, up.z);
}

void
GlRenderer::_RenderScene()
{
  ObjectContainer::const_iterator oi = mObjects.begin();

  for (; oi != mObjects.end(); oi++)
	RenderIntersectable(*oi);
}

bool
GlRenderer::RenderScene()
{
  static int glList = -1;
  if (mUseGlLists) {
	if (glList == -1) {
	  glList = glGenLists(1);
	  glNewList(glList, GL_COMPILE);
	  _RenderScene();
	  glEndList();
	}
	glCallList(glList);
  } else
	_RenderScene();
	
  
  return true;
}


void
GlRendererBuffer::EvalQueryWithItemBuffer(
										  //RenderCostSample &sample
									   )
{
	// read back the texture
	glReadPixels(0, 0,
				GetWidth(), GetHeight(),
				GL_RGBA,
				GL_UNSIGNED_BYTE,
				mPixelBuffer);
		
			
	unsigned int *p = mPixelBuffer;
			
	for (int y = 0; y < GetHeight(); y++)
	{
		for (int x = 0; x < GetWidth(); x++, p++) 
		{
			unsigned int id = (*p) & 0xFFFFFF;

			if (id != 0xFFFFFF)
				++ mObjects[id]->mCounter;
		}
	}
}



/****************************************************************/
/*               GlRendererBuffer implementation                */
/****************************************************************/



GlRendererBuffer::GlRendererBuffer(SceneGraph *sceneGraph,
								   ViewCellsManager *viewcells,
								   KdTree *tree):
GlRenderer(sceneGraph, viewcells, tree)  
{
	mPixelBuffer = NULL;

	// implement width and height in subclasses
}


void
GlRendererBuffer::EvalQueryWithOcclusionQueries(
									   //RenderCostSample &sample
									   )
{
	glDepthFunc(GL_LEQUAL);
		
	glColorMask(GL_FALSE, GL_FALSE, GL_FALSE, GL_FALSE);
	glDepthMask(GL_FALSE);


	// simulate detectemptyviewspace using backface culling
	if (mDetectEmptyViewSpace) 
	{
		glEnable(GL_CULL_FACE);
		//cout << "culling" << endl;
	}
	else
	{
		//cout << "not culling" << endl;
		glDisable(GL_CULL_FACE);
	}

	
	//const int numQ = 1;
	const int numQ = (int)mOcclusionQueries.size();
	
	//glFinish();
#if 0
	//-- now issue queries for all objects
	for (int j = 0; j < (int)mObjects.size(); ++ j) 
	{
		mOcclusionQueries[j]->BeginQuery();
		RenderIntersectable(mObjects[j]);
		mOcclusionQueries[j]->EndQuery();

		unsigned int pixelCount;

		pixelCount = mOcclusionQueries[j]->GetQueryResult();
		mObjects[j]->mCounter += pixelCount;
	}
#else

	int q = 0;

	//-- now issue queries for all objects
	for (int j = 0; j < (int)mObjects.size(); j += q) 
	{	
		for (q = 0; ((j + q) < (int)mObjects.size()) && (q < numQ); ++ q) 
		{
			//glFinish();
			mOcclusionQueries[q]->BeginQuery();
			
			RenderIntersectable(mObjects[j + q]);
		
			mOcclusionQueries[q]->EndQuery();
			//glFinish();
		}
		//cout << "q: " << q << endl;
		// collect results of the queries
		for (int t = 0; t < q; ++ t) 
		{
			unsigned int pixelCount;
		
			//-- reenable other state
#if 0
			bool available;

			do 
			{
				available = mOcclusionQueries[t]->ResultAvailable();
				
				if (!available) cout << "W";
			} 
			while (!available);
#endif

			pixelCount = mOcclusionQueries[t]->GetQueryResult();

			//if (pixelCount > 0)
			//	cout <<"o="<<j+q<<" q="<<mOcclusionQueries[q]->GetQueryId()<<" pc="<<pixelCount<<" ";
			mObjects[j + t]->mCounter += pixelCount;
		}

		//j += q;
	}
#endif
	//glFinish();
	glColorMask(GL_TRUE, GL_TRUE, GL_TRUE, GL_TRUE);
	glDepthMask(GL_TRUE);
	
	glEnable(GL_CULL_FACE);
}


void
GlRendererBuffer::RandomViewPoint()
{ 
  // do not use this function since it could return different viewpoints for
  // different executions of the algorithm

  //  mViewCellsManager->GetViewPoint(mViewPoint);

  while (1) {
	Vector3 pVector = Vector3(halton.GetNumber(1),
							  halton.GetNumber(2),
							  halton.GetNumber(3));
	
	mViewPoint =  mViewCellsManager->GetViewSpaceBox().GetPoint(pVector);
	ViewCell *v = mViewCellsManager->GetViewCell(mViewPoint);
	if (v && v->GetValid())
	  break;
	// generate a new vector
	halton.GenerateNext();
  }
  
  Vector3 dVector = Vector3(2*M_PI*halton.GetNumber(4),
							M_PI*halton.GetNumber(5),
							0.0f);
  
  mViewDirection = Normalize(Vector3(sin(dVector.x),
									 //									 cos(dVector.y),
									 0.0f,
									 cos(dVector.x)));
  halton.GenerateNext();
}


void
GlRenderer::RenderBox(const AxisAlignedBox3 &box)
{

  glBegin(GL_LINE_LOOP);
  glVertex3d(box.Min().x, box.Max().y, box.Min().z );
  glVertex3d(box.Max().x, box.Max().y, box.Min().z );
  glVertex3d(box.Max().x, box.Min().y, box.Min().z );
  glVertex3d(box.Min().x, box.Min().y, box.Min().z );
  glEnd();

  glBegin(GL_LINE_LOOP);
  glVertex3d(box.Min().x, box.Min().y, box.Max().z );
  glVertex3d(box.Max().x, box.Min().y, box.Max().z );
  glVertex3d(box.Max().x, box.Max().y, box.Max().z );
  glVertex3d(box.Min().x, box.Max().y, box.Max().z );
  glEnd();

  glBegin(GL_LINE_LOOP);
  glVertex3d(box.Max().x, box.Min().y, box.Min().z );
  glVertex3d(box.Max().x, box.Min().y, box.Max().z );
  glVertex3d(box.Max().x, box.Max().y, box.Max().z );
  glVertex3d(box.Max().x, box.Max().y, box.Min().z );
  glEnd();

  glBegin(GL_LINE_LOOP);
  glVertex3d(box.Min().x, box.Min().y, box.Min().z );
  glVertex3d(box.Min().x, box.Min().y, box.Max().z );
  glVertex3d(box.Min().x, box.Max().y, box.Max().z );
  glVertex3d(box.Min().x, box.Max().y, box.Min().z );
  glEnd();

  glBegin(GL_LINE_LOOP);
  glVertex3d(box.Min().x, box.Min().y, box.Min().z );
  glVertex3d(box.Max().x, box.Min().y, box.Min().z );
  glVertex3d(box.Max().x, box.Min().y, box.Max().z );
  glVertex3d(box.Min().x, box.Min().y, box.Max().z );
  glEnd();

  glBegin(GL_LINE_LOOP);
  glVertex3d(box.Min().x, box.Max().y, box.Min().z );
  glVertex3d(box.Max().x, box.Max().y, box.Min().z );
  glVertex3d(box.Max().x, box.Max().y, box.Max().z );
  glVertex3d(box.Min().x, box.Max().y, box.Max().z );

  glEnd();

}

void
GlRenderer::RenderBvhNode(BvhNode *node)
{
  if (node->IsLeaf()) {
	BvhLeaf *leaf = (BvhLeaf *) node;
	for (int i=0; i < leaf->mObjects.size(); i++)
		cout << "leaf obj " << i << endl;
	  //RenderIntersectable(mObjects[i]);
  } else {
	BvhInterior *in = (BvhInterior *)node;
	RenderBvhNode(in->GetBack());
	RenderBvhNode(in->GetFront());
  }
  
}

}