#include "Visualization.h"
#include "glInterface.h"
#include "Camera.h"
#include "SceneEntity.h"
#include "Bvh.h"
#include "RenderState.h"
#include "ShadowMapping.h"
#include "ViewCellsTree.h"
#include "Material.h"


#include <stack>


using namespace std;


namespace CHCDemoEngine
{


void Visualization::RenderBoxForViz(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();
}


/******************************************************/
/*           Vizualization implementation             */
/******************************************************/


Visualization::Visualization(Bvh *bvh, 
							 PerspectiveCamera *camera, 
							 Camera *vizCamera, 
							 RenderState *renderState): 
mBvh(bvh), 
mCamera(camera),
mVizCamera(vizCamera),
mRenderState(renderState),
mFrameId(0),
mViewCell(NULL)
{
}


Visualization::~Visualization() 
{
}


void Visualization::SetHierarchy(Bvh *bvh)
{
	mBvh = bvh;
}


void Visualization::SetRenderState(RenderState *state)
{
	mRenderState = state;
}


void Visualization::SetFrameId(int frameId)
{
	mFrameId = frameId;
}


void Visualization::SetViewCell(ViewCell *vc)
{
	mViewCell = vc;
}


static Technique GetVizTechnique()
{
	Technique tech;
	tech.Init();

	//tech.SetLightingEnabled(false);
	//tech.SetDepthWriteEnabled(false);

	tech.SetEmmisive(RgbaColor(1.0f, 1.0f, 1.0f, 1.0f));
	tech.SetDiffuse(RgbaColor(1.0f, 1.0f, 1.0f, 1.0f));
	tech.SetAmbient(RgbaColor(1.0f, 1.0f, 1.0f, 1.0f));

	return tech;
}


void Visualization::Render(bool showShadowFrustra)
{
	stack<BvhNode *> tStack;
	tStack.push(mBvh->GetRoot());

	glEnableClientState(GL_VERTEX_ARRAY);
	glEnableClientState(GL_NORMAL_ARRAY);

	while (!tStack.empty())
	{
		BvhNode *node = tStack.top();
		tStack.pop();

		if (!node->IsVirtualLeaf())
		{
			BvhInterior *interior = static_cast<BvhInterior *>(node);

			tStack.push(interior->GetFront());
			tStack.push(interior->GetBack());
		}
		else
		{
			if (node->GetLastRenderedFrame() == mFrameId)
			{
				int geometrySize;
				SceneEntity **entities = mBvh->GetGeometry(node, geometrySize);

				for (int i = 0; i < geometrySize; ++ i)
				{
					SceneEntity *ent = entities[i];
					
					if (ent->IsVisible())
						ent->Render(mRenderState);
				}		
			}
		}
	}

	// render current view cell
	static Technique vcTechnique = GetVizTechnique();

	if (mViewCell)
	{
		vcTechnique.Render(mRenderState);
		RenderBoxForViz(mViewCell->GetBox());
	}

	glDisableClientState(GL_VERTEX_ARRAY);
	glDisableClientState(GL_NORMAL_ARRAY);


	mRenderState->Reset();

	glPushAttrib(GL_CURRENT_BIT);
	glDisable(GL_LIGHTING);
	glDisable(GL_DEPTH_TEST);
	glDepthMask(GL_FALSE);

	RenderFrustum();

	if (showShadowFrustra)
		ShadowMap::VisualizeFrustra();

	Vector3 pos = mCamera->GetPosition();

	// coordinates
	glColor3f(0.0f, 1.0f, 0.0f);
	glBegin(GL_LINES);
	glVertex3d(pos.x, pos.y, pos.z);
	glVertex3d(pos.x + 100, pos.y, pos.z);
	glEnd();

	glColor3f(0.0f, 0.0f, 1.0f);
	glBegin(GL_LINES);
	glVertex3d(pos.x, pos.y, pos.z);
	glVertex3d(pos.x, pos.y + 100, pos.z);
	glEnd();

	//RenderBoxForViz(mBvh->GetBox());

	glDepthMask(GL_TRUE);
	glPopAttrib();
}


void Visualization::RenderFrustum()
{
	glColor3f(1.0f, 0.0f, 0.0f);

	Vector3 ftl, ftr, fbl, fbr, ntl, ntr, nbl, nbr;
	mCamera->ComputePoints(ftl, ftr, fbl, fbr, ntl, ntr, nbl, nbr);

	glLineWidth(2);

	glBegin(GL_LINE_LOOP);
	glVertex3d(fbl.x, fbl.y, fbl.z);
	glVertex3d(ftl.x, ftl.y, ftl.z);
	glVertex3d(ntl.x, ntl.y, ntl.z);
	glVertex3d(nbl.x, nbl.y, nbl.z);
	glEnd();

	glBegin(GL_LINE_LOOP);
	glVertex3d(fbr.x, fbr.y, fbr.z);
	glVertex3d(ftr.x, ftr.y, ftr.z);
	glVertex3d(ntr.x, ntr.y, ntr.z);
	glVertex3d(nbr.x, nbr.y, nbr.z);
	glEnd();

	glBegin(GL_LINE_LOOP);
	glVertex3d(fbr.x, fbr.y, fbr.z);
	glVertex3d(fbl.x, fbl.y, fbl.z);
	glVertex3d(nbl.x, nbl.y, nbl.z);
	glVertex3d(nbr.x, nbr.y, nbr.z);
	glEnd();

	glBegin(GL_LINE_LOOP);
	glVertex3d(ftr.x, ftr.y, ftr.z);
	glVertex3d(ftl.x, ftl.y, ftl.z);
	glVertex3d(ntl.x, ntl.y, ntl.z);
	glVertex3d(ntr.x, ntr.y, ntr.z);
	glEnd();
}


}