#include <iostream>
using namespace std;
#include "TFile.h"
#include "TTree.h"
#include "TEvent_Det.h"

void WriteFile() {
	TEvent_Det* e = new TEvent_Det;
	TFile* OutFile = new TFile("File1.root", "RECREATE");
	TTree* OutTree = new TTree("Tree1", "Tree containing nonsense");
	OutTree->Branch("Event", "TEvent_Det", &e);
	for (int i=0; i<1E3; i++) {
		e->Clear();
		e->FillRandom();
		OutTree->Fill();
	}
	OutFile->Write();
	delete e;
	delete OutFile;
}
	

void CopySomeEvents() {
 //Reading:
	TEvent_Det* Evt = new TEvent_Det;
	TFile* InFile = new TFile("File1.root", "READ");
	TTree* InTree = (TTree*)InFile->Get("Tree1");
	InTree->SetBranchAddress("Event", &Evt);
	int nEvents = InTree->GetEntries();
	cout << "There are " << nEvents << " events in the tree." << endl;
	if (nEvents>1000)
		nEvents = 1000;
	cout << "Going to read " << nEvents << endl;
 //Writing:
	TFile* OutFile = new TFile("File2.root", "RECREATE");
	TTree* OutTree = new TTree("Tree1", "Tree containing nonsense");
	OutTree->Branch("Event", "TEvent_Det", &Evt);
	for (int i=0; i<nEvents; i++) {
		InTree->GetEvent(i);
		if (fabs(Evt->Delays[0]) < 0.2)
			OutTree->Fill();
	}
	OutFile->Write();
	OutFile->Close();
	InFile->Close();
}


void eventproblem(bool Write) {
	if (Write) {
		cout << "Writing some random data...";
		WriteFile();
		cout << "... done." << endl << "Now trying to read some stuff from the file and copy it to a new one:" << endl;
	} else
		cout << "Trying to read data from existing file and copy it to a new one." << endl;
	
	CopySomeEvents();
	cout << "The end." << endl;
}