/**
 * @file geoEveViewer.cc
 * @brief 
 * @author John Watts
 * @version 0.1
 * @date 2015-08-21
 */

#include <Riostream.h>
#include <TROOT.h>
#include <TSystem.h>
#include <TVector3.h>
#include <TRegexp.h>
#include <TList.h>

#include <TGeoManager.h>
#include <TGeoVolume.h>
#include <TGeoNode.h>
#include <TVirtualGeoTrack.h>
#include <TGeoMaterial.h>

#include <TEveManager.h>
#include <TEveGeoNode.h>
#include <TEveCompound.h>
#include <TEveLine.h>
#include <TGLViewer.h>

#include <vector>

/**
 * @brief 
 * Display a gdml file in an eve viewer
 *
 * @param TString geoname	name of gdml file to display
 */
class geoEveViewer{
	public:
		/**
 		* @brief 
 		* Constructor
 		*
 		* @param TString geoname	name of gdml file to display
 		*/
		geoEveViewer(TString geoname="geometry.gdml");

		/**
 		* @brief 
 		* Destructor
 		*/
		virtual ~geoEveViewer();

		/**
 		* @brief 
 		* Get get the TGeoManager
 		* @return TGeoManager*  
 		*/
		TGeoManager* Get_Manager(){return geo_manager; };

		/**
 		* @brief 
 		* Get the top volume of the geometry
 		* @return TGeoVolume* 
 		*/
		TGeoVolume* GetTopVolume(){return geo_manager->GetTopVolume(); };

		/**
 		* @brief 
 		* Print the geometry volume tree
 		*/
		void Print_Volumes(){geo_manager->GetListOfVolumes()->Print(); };

		/**
 		* @brief 
 		* Export the geometry volume tree to a root file
 		*/
		void Export(){ geo_manager->Export(geoname(0,geoname.Length()-5)+".root","manager","vg"); };

		/**
 		* @brief 
 		* Print the node tree
 		*/
		void Print_Nodes(TObjArray* vlist=0);

		/**
 		* @brief 
 		* Shoot a vector from a given point in a given direction through the geometry
 		* and optional print the encounter volumes
 		* @param TVector3 pstart 	Starting point
 		* @param TVector3 dirstart	Starting direction (direction cosines)
 		* @param Bool_t verbose		kTRUE/print out encountered volumes
 		* @return std::vector<TString> 	A vector of encountered volume names
 		*/
		std::vector<TString>  Start_Track(TVector3 pstart=	TVector3(0.,0.,0.),
				                  TVector3 dirstart=	TVector3(0.,0.,1.),
						  Bool_t verbose=	kTRUE);

		/**
 		* @brief 
 		* Draw the geometry
 		* @param TString pviewer The type of viewer to use for display
 		* Types are eve, pad, ogl, and x3d 
 		*/
		void Draw(TString pviewer="eve");

		/**
 		* @brief 
 		* Display the geometry using raytrace
 		*/
		void Raytrace();

		/**
 		* @brief 
 		* Shoot a vector from a given point in a given direction through the geometry
 		* and print the encounter volumes
 		* @param TVector3 pstart 	Starting point
 		* @param TVector3 dirstart	Starting direction (direction cosines)
 		*/
		void Print_Stack(TString filter="*",
				 TVector3 top=TVector3(0.,0.,0.),
				 TVector3 dir=TVector3(0.,0.,1.));

		/**
 		* @brief 
 		* Shoot a vector from a given point in a given direction through the geometry
 		* @param Char_t ptransparency Set the geometry tranparency 0/clear 100/opake
 		*/
		void SetTransparency(Char_t ptransparency=50);
	protected:
		void DrawTrack(TVirtualGeoTrack *track);
		TGeoManager* geo_manager;
		TEveManager* evem;
		TEveCompound* cmp;
		TString viewer;
		Color_t color;
		Char_t transparency;
		TString geoname;
};

//**********************************************************************

geoEveViewer::geoEveViewer(TString pgeoname) : 
		geoname(pgeoname), evem(0), viewer("eve"), color(0), transparency(50)
{
//	TString expand=gSystem->ExpandFileName(geoname);	//TGDMLParse::StartGDML does not properly expand file names
//	geo_manager=TGeoManager::Import(expand);
	geo_manager=TGeoManager::Import(geoname);
	geo_manager->SetNsegments(40);
	TIterator *volumes=geo_manager->GetListOfVolumes()->MakeIterator();
	TGeoVolume *volume;
	while( ( volume=(TGeoVolume*)(volumes->Next()) ) ){
		volume->SetLineColor(color);
		volume->SetTransparency(transparency);
		color++;
		color=(color)%216;
		}
	color=2;
	Draw(viewer);
};

//**********************************************************************

geoEveViewer::~geoEveViewer()
{
	delete geo_manager;
};

//**********************************************************************

void geoEveViewer::Print_Nodes(TObjArray* vlist)
{
	if ( vlist==0 ) vlist=geo_manager->GetListOfNodes();
	vlist->Print();
	for(Int_t i=0; i<vlist->GetEntriesFast(); i++){
		TGeoNode* node=(TGeoNode*)vlist->At(i);
		if( node->GetNdaughters() > 0 )Print_Nodes(node->GetNodes());	//recursize call
		}
};

//**********************************************************************

void geoEveViewer::Draw(TString pviewer)
{
	//viewers: eve,pad,ogl,x3d 
	viewer=pviewer;
	if( viewer != "eve" ){
		GetTopVolume()->Draw(viewer);
   		geo_manager->DrawTracks();
		return;
	}else if( !evem ){ 	// Make Eve Window Manager
     		evem=TEveManager::Create();
		TGeoNode *node=geo_manager->GetTopNode();
   		TEveGeoTopNode* its = new TEveGeoTopNode(geo_manager, node);
		its->SetVisOption(0);
   		its->UseNodeTrans();
   		evem->AddGlobalElement(its);
		cmp = new TEveCompound("Tracks");
   		cmp->SetMainColor(kGreen);
   		evem->AddElement(cmp);
		}
   	evem->GetDefaultGLViewer()->UpdateScene();
};

//**********************************************************************

void geoEveViewer::DrawTrack(TVirtualGeoTrack *track)
{
	//Process tracks
	if( viewer != "eve" )return;
   	cmp->OpenCompound();
	TEveLine *line=new TEveLine;
	line->SetMainColor(color);
   	line->SetLineStyle(1);
   	line->SetLineWidth(1);
//	line->SetMarkerColor(color);
	line->SetRnrPoints(true);
	for(Int_t j=0; j<track->GetNpoints(); j++){
		Double_t x,y,z,t;
		track->GetPoint(j, x, y, z, t);
		line->SetNextPoint(x, y, z);
		}
   	cmp->AddElement(line);
	color++;
	color=(color)%216;
   	cmp->CloseCompound();
   	evem->Redraw3D(kFALSE);
};

//**********************************************************************

void geoEveViewer::Raytrace()
{
	GetTopVolume()->Raytrace();
};

//**********************************************************************

void geoEveViewer::Print_Stack(TString filter, TVector3 top, TVector3 dir)
{
    TRegexp reg(filter, 1);
    std::vector<TString> pname=Start_Track(top, dir, false);
    TVirtualGeoTrack *track=geo_manager->GetTrackOfId(0);
    for(Int_t i=0; i<track->GetNpoints(); i++){
    	    if( !(pname[i](reg) == 1) ){
	    	const Double_t* point=track->GetPoint(i);
	    	cout<<setw(10)<<i
		    <<setw(38)<<pname[i]
		    <<setw(10)<<point[0] 
		    <<setw(10)<<point[1] 
		    <<setw(10)<<point[2]
		    <<endl;
    	        };
    	    }
};

//**********************************************************************

std::vector<TString> geoEveViewer::Start_Track(TVector3 pstart, TVector3 dirstart, Bool_t verbose)
{
   TGeoNode *nextnode=geo_manager->InitTrack(
		   pstart.x(), pstart.y(), pstart.z(),
		   dirstart.x(), dirstart.y(), dirstart.z());
   Int_t id(0);
   Int_t track_index=geo_manager->AddTrack(id, 0, 0);
   TVirtualGeoTrack *track=geo_manager->GetTrack(track_index);
   Double_t time(0.);
   track->AddPoint(pstart.x(), pstart.y(), pstart.z(), time);
   const char *path = geo_manager->GetPath();
   TString name=nextnode->GetName();
   if(verbose)cout<<" Start Node "<<name<<" Current path is: "<<path<<endl;
   std::vector<TString> pointname;
   pointname.push_back(name);
   while( (nextnode=geo_manager->FindNextBoundaryAndStep()) ){
		name=nextnode->GetName();
		pointname.push_back(name);
           	TVector3 point=geo_manager->GetCurrentPoint();
	   	track->AddPoint(point.x(), point.y(), point.z(), time);
	   	time++;
		if(verbose){
	   		Double_t step=geo_manager->GetStep();
	   		Double_t safety=geo_manager->GetSafeDistance();
	   		cout<<setw(6)<<"Step" 		<<setw(12)<<step
			    <<setw(8)<<"Safety" 	<<setw(5)<<safety;
	   		cout<<setw(10)<<"Next Node" 	<<setw(38)<<name;
	   		cout<<setw(10)<<"Location"
			    <<setw(10)<<point.x() 	<<setw(10)<<point.y() 	<<setw(10)<<point.z();
 			cout<<setw(11)<<"Material"
		 	    <<setw(12)<<nextnode->GetMedium()->GetMaterial()->GetName()<<endl;
			}
		}
   DrawTrack(track);
   return pointname;
};

//**********************************************************************

//transparency is integer percent 0/opacque 100/invisiable
void geoEveViewer::SetTransparency(Char_t ptransparency)
{
	transparency=ptransparency;
	TIter materials(geo_manager->GetListOfMaterials());
	while (TGeoMaterial *m = (TGeoMaterial *)materials())m->SetTransparency(transparency);
	Draw(viewer);
	return;
};