# include <cmath>
# include <cstdlib>
# include <cstring>
# include <fstream>
# include <iomanip>
# include <iostream>

using namespace std;

# include "tsp_display.hpp"

//****************************************************************************80

void tsp_display ( string prefix, int n, double *x2 )

//****************************************************************************80
//
//  Purpose:
//
//    tsp_display() plots cities and a tour connecting them.
//
//  Discussion:
//
//    If a "round trip" is desired, then the x2 array must repeat the
//    first city at the end.
//
//  Licensing:
//
//    This code is distributed under the MIT license.
//
//  Modified:
//
//    13 June 2026
//
//  Author:
//
//    John Burkardt
//
//  Input:
//
//    string prefix: a string that defines the name of
//    the problem.  It is also used to create file names needed for
//    input to gnuplot.
//
//    int n: the number of cities.
//
//    double x[n*2]: the x and y coordinates of the cities.
//
{
  string command_filename;
  ofstream command;
  ofstream data;
  string data_filename;
  int i;
//
//  Create the data file.
//
  data_filename = prefix + "_data.txt";
  data.open ( data_filename.c_str ( ) );
  for ( i = 0; i < n; i++ )
  {
    data << x2[2*i] << "  " << x2[2*i+1] << "\n";
  }
  data.close ( );
  cout << "  Created data file '" << data_filename << "'\n";
//
//  Create the command file.
//
  command_filename = prefix + "_commands.txt";
  command.open ( command_filename.c_str ( ) );

  command << "# " << command_filename << "\n";
  command << "#\n";
  command << "# Usage:\n";
  command << "#  gnuplot < " << command_filename << "\n";
  command << "#\n";
  command << "set term png\n";
  command << "set output '" << prefix << ".png'\n";
  command << "set xlabel '<--- X --->'\n";
  command << "set ylabel '<--- Y --->'\n";
  command << "set title '" << prefix << "'\n";
  command << "set grid\n";
  command << "unset key\n";
  command << "set style data lines\n";
  command << "plot '" << data_filename 
          << "' using 1:2 lw 3 linecolor rgb 'blue', \\\n";
  command << "     '" << data_filename 
          << "' using 1:2 with points pointtype 7 pointsize 3 linecolor rgb 'green'\n";
  command << "quit\n";
  command.close ( );
  cout << "  Created command file '" << command_filename << "'\n";

  return;
}