#include<cstdlib>
#include<iostream>
#include<string>
#include<fstream>
#include<sstream>

// ROOT
#include<TApplication.h>
#include<TCanvas.h>
#include<TFile.h>
#include<TChain.h>
#include<TEventList.h>

// GERDA
#include<MGTEvent.hh>
#include<MGTWaveform.hh>

using namespace std;

int waitForEnter();

int main( int argc , char** argv ) {
    
    // Help message
	if ( argc == 2 && strcmp( argv[1] , "--help" ) == 0 ) {
        cout << endl
             << "Event browser for tier1 data tree."                  << endl
		     << endl
             << "Usage:   ./analysis [filelist] [OPTIONS]"            << endl
		     << "Options: --help: display this help message and exit" << endl
             << endl;
		return 0;
	} 

    cout << "Reading the input..." << endl;
    
    // Retrieve file names
    vector<string> listOfFiles;
    ifstream filelist( argv[1] );
    string name;
    while ( filelist >> name ) listOfFiles.push_back(name);

    // Retrieve tier1 files
    TChain chain("MGTree");
    for ( unsigned int i = 0 ; i < listOfFiles.size()-2 ; i++ ) {
        chain.Add(listOfFiles.at(i).c_str());
    }

    // Retrieve list file
    TFile fileWithList( listOfFiles.at(listOfFiles.size()-1).c_str() , "READ" );
    TEventList * list = (TEventList*)fileWithList.Get("listofselected")->Clone();
       
    MGTEvent * event = NULL;
    MGTWaveform * wf = NULL;
    TH1D * hist      = NULL; 
    TApplication app( "app" , &argc , argv );
    TCanvas can( "loopCan" , "GERDA tier1" , 7500 , 5500 , 650 , 350 );
    can.SetGrid();
    can.cd();
    
    // Fundamental: draw something before beginning the loop
    chain.SetBranchAddress( "event" , &event );
    chain.GetEntry(0);
    wf = event->GetWaveform(0);
    hist = wf->GimmeHist();
    if ( list->Contains(0) ) hist->SetLineColor(kRed);
    hist->Draw();
    cout << endl
         << "Press \"enter\" for next event,"    << endl
         << "\"-\" for previous event,"          << endl
         << "\"goto\" to go to a specific event" << endl
         << "or type \"exit\" to quit: "         << endl << endl
         << "event 0:"                           << endl;
    can.ForceUpdate();

    int N = chain.GetEntries();
    int i =  1;
    ostringstream convert;
    string title;
    
    while ( 1 == 1 ) {
        
        cout << "event " << i << ": ";
        //cout << flush;
        hist->SetLineColor(kBlue);
        chain.GetEntry(i);
        wf = event->GetWaveform(0);
        
        hist = wf->GimmeHist();
            hist->SetStats(kFALSE);
            convert.str("");
            convert << i;
            title = convert.str();
            hist->SetTitle( title.c_str() );
        if ( list->Contains(i) ) hist->SetLineColor(kRed);       
        can.ForceUpdate();

        int choice = waitForEnter();
        if ( choice == 1 ) break;
        if ( choice == 2 && i < N ) i++;
        if ( choice == 2 && i == N ) continue;
        if ( choice == 3 && i > 0 ) i--;
        if ( choice == 3 && i == 0 ) continue;
        if ( choice == 4 ) {
            cout << "           Go to: ";
            cin >> i;
        }
    }
    
    cout << "Close the ROOT session to exit the program";
    app.Run(kFALSE);

    return 0;
}

int waitForEnter() {
    string input;
    getline( cin , input );
    if ( input.compare("exit") == 0 ) return 1;
    if ( input.compare("-") == 0 )    return 3;
    if ( input.compare("goto") == 0 ) return 4;
    else return 2;
}