#include "ObjManualMeshLoader.h"
#include "Triangle3.h"
#include "IntersectableWrapper.h"
#include "BvHierarchy.h"
#include "OgreLogManager.h"

#define USE_HBL_DISCARD 1

ObjManualMeshLoader::ObjManualMeshLoader(GtpVisibilityPreprocessor::BvhLeaf *obj):
mObject(obj)
{
}


ObjManualMeshLoader::~ObjManualMeshLoader()
{
}


void ObjManualMeshLoader::loadResource(Ogre::Resource *resource)
{
	using namespace Ogre;

	Mesh *mesh = (Mesh *) resource;
	SubMesh* submesh = mesh->createSubMesh();

	const int triCount = (int)mObject->mObjects.size();
	const int vertexCount = triCount * 3;

	// We must create the vertex data, indicating how many vertices there will be
	submesh->useSharedVertices = false;
	submesh->vertexData = new VertexData();
	submesh->vertexData->vertexStart = 0;
	submesh->vertexData->vertexCount = vertexCount;

	static const unsigned short source = 0;
	size_t offset = 0;

	// We must now declare what the vertex data contains
	VertexDeclaration* declaration = submesh->vertexData->vertexDeclaration;

	offset += declaration->addElement(source, offset, VET_FLOAT3, VES_POSITION).getSize();
	offset += declaration->addElement(source, offset, VET_FLOAT3, VES_NORMAL).getSize();
	//offset += declaration->addElement(source, offset, VET_FLOAT2,VES_TEXTURE_COORDINATES).getSize();

	HardwareVertexBufferSharedPtr vbuffer = HardwareBufferManager::getSingleton().
		createVertexBuffer(declaration->getVertexSize(source),
						   submesh->vertexData->vertexCount,
						   HardwareBuffer::HBU_STATIC_WRITE_ONLY);

    // we get access to the buffer to fill it.  During so we record the bounding box.
	AxisAlignedBox aabox;

	submesh->vertexData->vertexBufferBinding->setBinding(source, vbuffer);
#if USE_HBL_DISCARD
	float* vdata = static_cast<float*>(vbuffer->lock(HardwareBuffer::HBL_DISCARD));
#else
	float* vdata = static_cast<float *>(vbuffer->lock(HardwareBuffer::HBL_NORMAL));
#endif

	GtpVisibilityPreprocessor::ObjectContainer::
		const_iterator oit, oit_end = mObject->mObjects.end();

	for (oit = mObject->mObjects.begin(); oit != oit_end; ++ oit)
	{
		GtpVisibilityPreprocessor::TriangleIntersectable *tObj = 
			static_cast<GtpVisibilityPreprocessor::TriangleIntersectable *>(*oit);
		
		const GtpVisibilityPreprocessor::Triangle3 tri = tObj->GetItem();
		const GtpVisibilityPreprocessor::Vector3 n = tri.GetNormal();

		for (int i = 0; i < 3; ++ i)
		{
			Vector3 vtx(tri.mVertices[i].x, tri.mVertices[i].y, tri.mVertices[i].z);
		
			*(vdata ++) = vtx.x;
			*(vdata ++) = vtx.y;
			*(vdata ++) = vtx.z;

			*(vdata ++) = n.x;
			*(vdata ++) = n.y;
			*(vdata ++) = n.z;

			aabox.merge(vtx);
		}
	}

	vbuffer->unlock();

#if 0
	RenderOperation rop;
	submesh->_getRenderOperation(rop);
	rop.useIndexes = false;
#endif
	//////
	//-- Creates the index data
    
	const int indexCount = vertexCount;
	submesh->indexData->indexStart = 0;
	submesh->operationType = RenderOperation::OT_TRIANGLE_LIST;

	// we use an index for every vertex
	submesh->indexData->indexCount = indexCount;
	submesh->indexData->indexBuffer =
	    HardwareBufferManager::getSingleton().
			createIndexBuffer(HardwareIndexBuffer::IT_16BIT,
							  submesh->indexData->indexCount,
							  HardwareBuffer::HBU_STATIC_WRITE_ONLY);

#if USE_HBL_DISCARD
	uint16* idata = static_cast<uint16 *>(submesh->indexData->indexBuffer->lock(HardwareBuffer::HBL_DISCARD));
#else
	uint16* idata = static_cast<uint16 *>(submesh->indexData->indexBuffer->lock(HardwareBuffer::HBL_NORMAL));
#endif
	for (int j = 0; j < indexCount; ++ j)
    {
		idata[j] = j;
    }
    
	submesh->indexData->indexBuffer->unlock();
	submesh->setMaterialName("BaseWhite"); 

	// indicate the bounding box
	mesh->_setBounds(aabox); 
	mesh->_setBoundingSphereRadius((aabox.getMaximum() - aabox.getMinimum()).length() / 2.0); 
}