//*
// Macro: osc_graph.C
//
// Crea grafici per le soluzioni numeriche dell'oscillatore armonico
//*

#include "TROOT.h"
#include "TStyle.h"
#include "TCanvas.h"
#include "TH2F.h"
#include "TGraph.h"
#include "TLegend.h"

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

using namespace std;

//--
//  Questa funzione ha lo stesso nome del file.
//  Viene eseguita tutte le volte che il file viene caricato dal prompt
//  di root con .L osc_graph.C oppure .L osc_graph.C+
//--
void osc_graph()
{
  gROOT->SetStyle("Plain");
  gStyle->SetOptStat(0);
  gStyle->SetOptTitle(kFALSE);
  gStyle->SetLabelOffset(0.01,"x");
  gStyle->SetLabelOffset(0.005,"y");
  gStyle->SetTitleOffset(1.4,"y");
  gStyle->SetTitleOffset(1.4,"x");
}

int read_datafile(const char *filename,
                  vector <double> & vtime, vector <double> & vx,
                  vector <double> & vv,    vector <double> & venergy)
{
    double value;

    if (filename == NULL) {
        cerr << "read_datafile() filename is NULL" << endl;
        return 1;
    }

    ifstream in(filename);
    if (! in.is_open() ) {
        cerr << "Cannot open data file \"" << filename << "\"\n";
        return 2;
    }

    while ( ! in.eof() ) {

        string line_buffer;
        getline(in, line_buffer);
        // cout << " buffer: " << line_buffer << endl;

        // Skip all lines starting with #
        if (line_buffer.size() && line_buffer[0] != '#') {

            stringstream extr(line_buffer);

            extr >> value;
            vtime.push_back(value);
            // cout << "Time: " << value << " ";
            extr >> value;
            vx.push_back(value);
            // cout << "x: " << value << endl;
            extr >> value;
            vv.push_back(value);
            extr >> value;
            venergy.push_back(value);
        }
    }

    in.close();

    return 0;
}

//--
//   Plot the data
//--
int plot_data(const char * f1="osc_euler_0.25.dat",
              const char * txt_f1="Eulero 0.25",
              const char * f2="osc_euler_cromer_0.25.dat",
              const char * txt_f2="Eulero Cromer 0.25",
              const char * f3="osc_euler_richardson_0.25.dat",
              const char * txt_f3="Eulero Richardson 0.25")

{
    int ret = 0;
    vector<double> v1_time, v1_x, v1_v, v1_energy;
    TGraph * g1 = NULL;
    vector<double> v2_time, v2_x, v2_v, v2_energy;
    TGraph * g2 = NULL;
    vector<double> v3_time, v3_x, v3_v, v3_energy;
    TGraph * g3 = NULL;

    if (f1) {
        ret = read_datafile(f1, v1_time, v1_x, v1_v, v1_energy);
        if (ret) {
            cerr << "read_datafile() error: " << ret << endl;
            return 1;
        }

        g1 = new TGraph( v1_time.size(), & v1_time[0], & v1_x[0]);
        // g1->GetXaxis()->SetTitle("time [s]");
        // g1->GetYaxis()->SetTitle("position [a.u.]");
        g1->SetMarkerColor(2);
        g1->SetLineColor(2);
        g1->SetMarkerStyle(28);
        g1->SetMarkerSize(0.9);
    }

    if (f2) {
        ret = read_datafile(f2, v2_time, v2_x, v2_v, v2_energy);
        if (ret) {
            cerr << "read_datafile() error: " << ret << endl;
            return 1;
        }

        g2 = new TGraph( v2_time.size(), & v2_time[0], & v2_x[0]);
        // g2->GetXaxis()->SetTitle("time [s]");
        // g2->GetYaxis()->SetTitle("position [a.u.]");
        g2->SetMarkerColor(8);
        g2->SetLineColor(8);
        g2->SetMarkerStyle(20);
        g2->SetMarkerSize(0.9);
    }

    if (f3) {
        ret = read_datafile(f3, v3_time, v3_x, v3_v, v3_energy);
        if (ret) {
            cerr << "read_datafile() error: " << ret << endl;
            return 1;
        }

        g3 = new TGraph( v3_time.size(), & v3_time[0], & v3_x[0]);
        // g3->GetXaxis()->SetTitle("time [s]");
        // g3->GetYaxis()->SetTitle("position [a.u.]");
        g3->SetMarkerColor(60);
        g3->SetLineColor(60);
        g3->SetMarkerStyle(3);
        g3->SetMarkerSize(0.9);
    }


    TCanvas * c3 = new TCanvas("c3","test");
    gPad->SetTopMargin(0.01);
    gPad->SetBottomMargin(0.12);
    gPad->SetRightMargin(0.01);
    gPad->SetLeftMargin(0.12);

    TH2F * frame_1  = new TH2F("frame_1", "", 10, -0.2, 10.2, 10, -4., 4.);
    frame_1->Draw();
    frame_1->GetXaxis()->SetTitle("time [s]");
    frame_1->GetXaxis()->SetLabelSize(0.05);
    frame_1->GetYaxis()->SetTitle("position [a.u.]");

    if (g1)         g1->Draw("psame");
    if (g2)         g2->Draw("psame");
    if (g3)         g3->Draw("psame");

    TLegend * leg = new TLegend(0.17,0.17,0.57,0.33);
    leg->SetHeader("Oscillatore Armonico");
    if (g1) leg->AddEntry(g1, txt_f1, "ep");
    if (g2) leg->AddEntry(g2, txt_f2, "ep");
    if (g3) leg->AddEntry(g3, txt_f3, "ep");
    leg->Draw();

    c3->Update();

    return 0;
}