#include "ViewCell.h"
#include "Mesh.h"
#include "Intersectable.h"
#include "MeshKdTree.h"
#include "Triangle3.h"

ViewCell::ViewCell(): MeshInstance(NULL), mPiercingRays(0)
{
}

ViewCell::ViewCell(Mesh *mesh): MeshInstance(mesh), mPiercingRays(0)
{
}

ViewCellPvs &ViewCell::GetPvs() 
{
	return mPvs;
}

int ViewCell::Type() const 
{ 
	return VIEW_CELL; 
}

void ViewCell::DeriveViewCells(const ObjectContainer &objects, 
							   ViewCellContainer &viewCells, 
							   const int maxViewCells)
{
	// maximal max viewcells
	int limit = maxViewCells > 0 ? Min((int)objects.size(), maxViewCells) : (int)objects.size();

	for (int i = 0; i < limit; ++ i)
	{
		Intersectable *object = objects[i];
		
		// extract the mesh instances
		if (object->Type() == Intersectable::MESH_INSTANCE)
		{
			MeshInstance *inst = dynamic_cast<MeshInstance *>(object);

			ViewCell *viewCell = new ViewCell(inst->GetMesh());
			viewCells.push_back(viewCell);
		}
		//TODO: transformed meshes
	}
}

ViewCell *ViewCell::ExtrudeViewCell(const Triangle3 &baseTri, const float height)
{
 int i; 
 // one mesh per view cell
	Mesh *mesh = new Mesh();
	
	//-- construct prism

	// bottom 
	mesh->mFaces.push_back(new Face(2,1,0));
	// top
    mesh->mFaces.push_back(new Face(3,4,5));
	// sides
	mesh->mFaces.push_back(new Face(1, 4, 3, 0));
	mesh->mFaces.push_back(new Face(2, 5, 4, 1));
	mesh->mFaces.push_back(new Face(3, 5, 2, 0));

	//--- extrude new vertices for top of prism
	Vector3 triNorm = baseTri.GetNormal();

	Triangle3 topTri;	

	// add base vertices and calculate top vertices
		for (i = 0; i < 3; ++ i)
		 mesh->mVertices.push_back(baseTri.mVertices[i]);
	
	// add top vertices	
																for (i = 0; i < 3; ++ i)
		mesh->mVertices.push_back(baseTri.mVertices[i] + height * triNorm);
	
	mesh->Preprocess();

	return new ViewCell(mesh);
}

ViewCell *ViewCell::Merge(ViewCell &front, ViewCell &back)
{
	ViewCell *vc = new ViewCell();
	// merge pvs
	vc->mPvs.Merge(front.mPvs, back.mPvs);

	// merge ray sets
	stable_sort(front.mPiercingRays.begin(), front.mPiercingRays.end());
	stable_sort(back.mPiercingRays.begin(), back.mPiercingRays.end());

	std::merge(front.mPiercingRays.begin(), front.mPiercingRays.end(),
			   back.mPiercingRays.begin(), back.mPiercingRays.end(), 
			   vc->mPiercingRays.begin());

	return vc;
}

void ViewCell::AddPassingRay(const Ray &ray, const int contributions)
{
	mPassingRays.AddRay(ray, contributions);
}