#include "dco.hpp"
/* G01GC_A1W_F C++ Header Example Program.
 *
 * Copyright 2021 Numerical Algorithms Group.
 * Mark 27.2, 2021.
 */

#include <iostream>
#include <nag.h>
#include <nagad.h>
#include <stdio.h>
#include <string>
using namespace std;

int main(void)
{
  int exit_status = 0;

  cout << "G01GC_A1W_F C++ Header Example Program Results\n\n";

  // Create AD tape
  dco::ga1s<double>::global_tape = dco::ga1s<double>::tape_t::create();

  // Skip heading in data file
  string mystr;
  getline(cin, mystr);

  // Read number of x values
  Integer n;
  cin >> n;

  cout << "    x       df      rlamda     p";
  cout << "          p'         df'     rlamda'\n";
  cout.setf(ios::scientific, ios::floatfield);
  cout.setf(ios::right);
  cout.precision(2);

  nagad_a1w_w_rtype tol;
  tol           = 0.0;
  Integer maxit = 100;

  nagad_a1w_w_rtype *x      = new nagad_a1w_w_rtype[n];
  nagad_a1w_w_rtype *df     = new nagad_a1w_w_rtype[n];
  nagad_a1w_w_rtype *rlamda = new nagad_a1w_w_rtype[n];

  // Create AD configuration data object
  Integer ifail     = -1;
  void *  ad_handle = 0;
  nag::ad::x10aa(ad_handle, ifail);
  if (ifail != 0)
    {
      exit_status = 1;
      exit(exit_status);
    }

  // Loop over x values
  for (Integer i = 0; i < n; ++i)
    {
      // Read next x, df, rlamda
      double xr, dfr, rr;
      cin >> xr;
      cin >> dfr;
      cin >> rr;

      x[i]      = xr;
      df[i]     = dfr;
      rlamda[i] = rr;

      // Register variables, i.e. differentiate w.r.t. x, df and rlamda
      dco::ga1s<double>::global_tape->register_variable(x[i]);
      dco::ga1s<double>::global_tape->register_variable(df[i]);
      dco::ga1s<double>::global_tape->register_variable(rlamda[i]);

      // Call NAG AD Routine
      nagad_a1w_w_rtype p;
      ifail = -1;
      nag::ad::g01gc(ad_handle, x[i], df[i], rlamda[i], tol, maxit, p, ifail);
      if (ifail != 0)
        {
          exit_status = 2;
          goto END;
        }

      // Reset adjoints, increment p, and evaluate adjoints
      dco::ga1s<double>::global_tape->zero_adjoints();
      double inc = 1.0;
      dco::derivative(p) += inc;
      ifail                                              = 0;
      dco::ga1s<double>::global_tape->sparse_interpret() = true;
      dco::ga1s<double>::global_tape->interpret_adjoint();

      // Get derivatives
      double dpdx, dpdd, dpdr;
      dpdx = dco::derivative(x[i]);
      dpdd = dco::derivative(df[i]);
      dpdr = dco::derivative(rlamda[i]);

      // Output results
      cout.width(9);
      cout << x[i];
      cout.width(9);
      cout << df[i];
      cout.width(9);
      cout << rlamda[i];
      cout.width(9);
      cout << p;
      cout.width(11);
      cout << dpdx;
      cout.width(11);
      cout << dpdd;
      cout.width(11);
      cout << dpdr << endl;

      // Remove computational data object and tape
    }
END:
  nag::ad::x10ab(ad_handle, ifail);
  dco::ga1s<double>::tape_t::remove(dco::ga1s<double>::global_tape);

  delete[] x;
  delete[] df;
  delete[] rlamda;
  return exit_status;
}