// in root all sizes are given in cm

#include "TSystem.h"
#include "TGeoManager.h"
#include "TGeoVolume.h"
#include "TGeoMaterial.h"
#include "TGeoMedium.h"
#include "TGeoPgon.h"
#include "TGeoMatrix.h"
#include "TGeoCompositeShape.h"
#include "TFile.h"
#include "TString.h"
#include "TList.h"
#include "TROOT.h"

#include <iostream>

// Name of geometry version and output file
const TString geoVersion = "tutorial4";
const TString FileName = geoVersion + ".root";
const TString FileName1 = geoVersion + "_geomanager.root";

// Names of the different used materials which are used to build the modules
// The materials are defined in the global media.geo file 
const TString KeepingVolumeMedium     = "air";
const TString BoxVolumeMedium         = "silicon";

// Distance of the center of the first detector layer [cm];
const Float_t First_Z_Position = 10; 
const Float_t Z_Distance = 10; 

// Silicon box for both module types
const Float_t Module_Size_X = 80.;
const Float_t Module_Size_Y = 80.;
const Float_t Module_Size_Z = .04;

// some global variables
TGeoManager* gGeoMan = NULL;  // Pointer to TGeoManager instance
TGeoVolume* gModules; // Global storage for module types

// Forward declarations
void create_materials_from_media_file();
TGeoVolume* create_detector();
void position_detector();
void add_alignable_volumes();

void Create_Tutorial4_Geometry() {
  // Load the necessary FairRoot libraries 
  gROOT->LoadMacro("$VMCWORKDIR/gconfig/basiclibs.C");
  basiclibs();
  gSystem->Load("libGeoBase");
  gSystem->Load("libParBase");
  gSystem->Load("libBase");

  // Load needed material definition from media.geo file
  create_materials_from_media_file();

  // Get the GeoManager for later usage
  gGeoMan = (TGeoManager*) gROOT->FindObject("FAIRGeom");
  gGeoMan->SetVisLevel(7);  

  // Create the top volume 

  TGeoVolume* top = new TGeoVolumeAssembly("TOP");
  gGeoMan->SetTopVolume(top);
 
  TGeoVolume* tut4 = new TGeoVolumeAssembly(geoVersion);
  top->AddNode(tut4, 1);
  
  gModules = create_detector();

  position_detector();
 
  cout<<"Voxelizing."<<endl;
  top->Voxelize("");
  gGeoMan->CloseGeometry();

  add_alignable_volumes();

  gGeoMan->CheckOverlaps(0.001);
  gGeoMan->PrintOverlaps();
  gGeoMan->Test();

  TFile* outfile = new TFile(FileName,"RECREATE");
  top->Write();
  outfile->Close();

  TFile* outfile = new TFile(FileName1,"RECREATE");
  gGeoMan->Write();
  outfile->Close();

  //  top->Draw("ogl");
  //top->Raytrace();

}

void create_materials_from_media_file()
{
  // Use the FairRoot geometry interface to load the media which are already defined
  FairGeoLoader* geoLoad = new FairGeoLoader("TGeo", "FairGeoLoader");
  FairGeoInterface* geoFace = geoLoad->getGeoInterface();
  TString geoPath = gSystem->Getenv("VMCWORKDIR");
  TString geoFile = geoPath + "/geometry/media.geo";
  geoFace->setMediaFile(geoFile);
  geoFace->readMedia();

  // Read the required media and create them in the GeoManager
  FairGeoMedia* geoMedia = geoFace->getMedia();
  FairGeoBuilder* geoBuild = geoLoad->getGeoBuilder();

  FairGeoMedium* air              = geoMedia->getMedium("air");
  FairGeoMedium* silicon          = geoMedia->getMedium("silicon");

  // include check if all media are found

  geoBuild->createMedium(air);
  geoBuild->createMedium(silicon);
}

TGeoVolume* create_detector()
{
 
  // needed materials
  TGeoMedium* SiliconVolMed   = gGeoMan->GetMedium(BoxVolumeMedium);

  // Single detector_layer
  TGeoBBox* det_plane = new TGeoBBox("", Module_Size_X/2., Module_Size_Y/2., Module_Size_Z/2.);
  TGeoVolume* det_plane_vol = 
    new TGeoVolume("tut4_det", det_plane, SiliconVolMed);
  det_plane_vol->SetLineColor(kBlue); // set line color 
  det_plane_vol->SetTransparency(70); // set transparency 
  TGeoTranslation* det_plane_trans 
    = new TGeoTranslation("", 0., 0., 0.);

  return det_plane_vol;

}

void position_detector()
{

  TGeoTranslation* det_trans=NULL;

  Int_t numDets=0;
  for (Int_t detectorPlanes = 0; detectorPlanes < 40; detectorPlanes++) {
    det_trans 
      = new TGeoTranslation("", 0., 0., First_Z_Position+(numDets*Z_Distance));
    gGeoMan->GetVolume(geoVersion)->AddNode(gModules, numDets, det_trans);
    numDets++;

  }
}

void add_alignable_volumes()
{

  TString volPath;
  TString symName;
  TString detStr   = "Tutorial4/det";
  TString volStr   = "/TOP_1/tutorial4_1/tut4_det_";

  for (Int_t detectorPlanes = 0; detectorPlanes < 40; detectorPlanes++) {

    volPath  = volStr;
    volPath += detectorPlanes;

    symName  = detStr;
    symName += Form("%02d",detectorPlanes);

    cout<<"Path: "<<volPath<<", "<<symName<<endl;
//    gGeoMan->cd(volPath);  
   
    gGeoMan->SetAlignableEntry(symName.Data(),volPath.Data());

  }
    cout<<"Nr of alignable objects: "<<gGeoMan->GetNAlignable()<<endl;

}