//======
// ROOT
//======
#include <TCanvas.h>
#include <TFile.h>
#include <TPolyLine.h>
#include <TString.h>
#include <TTree.h>


//=========
// STD C++
//=========
#include <iostream>


using namespace std;



void photTrajectory( TString inFilename = "", Double_t photonID = 1 ) // ID 0 means all
{

	if( inFilename == "" )
	{
		cout << "Usage: photTrajectory( filename, photonID )" << endl;
		return;
	}


//==============================================================================
// Access to the input ROOT-file & canvas settings
//==============================================================================
	TFile *inFile = new TFile( inFilename );
	TCanvas *setup = (TCanvas*) inFile->Get("Setup");

    TTree *infoTree   = (TTree*) inFile->Get("info");
	TTree *photonTree = (TTree*) inFile->Get("photon");


    Int_t refl_limit;
    infoTree->SetBranchAddress( "refl_limit", &refl_limit );
    infoTree->GetEntry( 0 );


    int add_pos = 1 + 3*2 + 1; // 1 start + 3 volume transition (+ tiny shifts) + detector
    const int pos_size = refl_limit + 1 + add_pos; // reflection limit + 1 exceed + additional positions
    Double_t posX[ pos_size ], posY[ pos_size ], posZ[ pos_size ];

    TString pos_size_str;
    pos_size_str += pos_size;
    pos_size_str.Remove( TString::kLeading, ' ' );
    TString posX_str = "posX[" + pos_size_str + "]";
    TString posY_str = "posY[" + pos_size_str + "]";
    TString posZ_str = "posZ[" + pos_size_str + "]";

	Int_t index_pos, nRefl;
	Bool_t measured, absorbed, lost;

    photonTree->SetBranchAddress( posX_str   , posX );
    photonTree->SetBranchAddress( posY_str   , posY );
    photonTree->SetBranchAddress( posZ_str   , posZ );
	photonTree->SetBranchAddress( "index_pos" , &index_pos );
	photonTree->SetBranchAddress( "nRefl"     , &nRefl );
	photonTree->SetBranchAddress( "measured"  , &measured );
	photonTree->SetBranchAddress( "absorbed"  , &absorbed );
	photonTree->SetBranchAddress( "lost"      , &lost );

	Int_t nEntries = photonTree->GetEntries();


	TCanvas *canvas = new TCanvas( "canvas", "" ,200, 10, 700, 510 );
	canvas->Draw();


//==============================================================================
// Event loop
//==============================================================================
	Int_t n_ph = 0;

	for( int i = 0; i < nEntries; i++ )
	{
		photonTree->GetEntry( i );
		n_ph++;

		if( n_ph == photonID || photonID == 0 )
		{
			cout << "Reflections: " << nRefl << endl;
			cout << "Fate       : ";
			if( measured == true )
				cout << "measured" << endl;
			if( absorbed == true )
				cout << "absorbed" << endl;
			if( lost == true )
				cout << "lost" << endl;

			for( int j = 0; j < index_pos; j++ )
			{
				if( j > 0 )
				{
					TPolyLine3D *l = new TPolyLine3D(2);

					l->SetPoint(0, posX[j-1], posY[j-1], posZ[j-1]);
					l->SetPoint(1, posX[j], posY[j], posZ[j]);
					l->SetLineColor(3);
					l->Draw();
				}

// 				cout << "pos.: (" << posX[j]<< "," << posY[j] << "," << posZ[j] << ")" << endl;
			}
		}
	}


//==============================================================================
// Plot
//==============================================================================
	setup->DrawClonePad();
	setup->Close(); // w/o -> Error in <RootX11ErrorHandler>


}