// SPDX-License-Identifier: EPL-2.0 OR GPL-2.0-or-later
// SPDX-FileCopyrightText: Bradley M. Bell <bradbell@seanet.com>
// SPDX-FileContributor: 2003-22 Bradley M. Bell
// ----------------------------------------------------------------------------

/*
Test of CondExp with AD< AD< Base > > types
*/

# include <cppad/cppad.hpp>

typedef CppAD::AD< double >     ADdouble;
typedef CppAD::AD< ADdouble > ADADdouble;

namespace { // BEGIN empty namespace

bool CondExpADOne(void)
{  bool ok = true;

   using namespace CppAD;
   size_t n = 3;
   size_t m = 8;

   // ADdouble independent variable vector
   CPPAD_TESTVECTOR( ADdouble ) Xa(n);
   Xa[0] = -1.;
   Xa[1] =  0.;
   Xa[2] =  1.;
   Independent(Xa);

   // ADdouble independent variable vector
   CPPAD_TESTVECTOR( ADADdouble ) Xaa(n);
   Xaa[0] = Xa[0];
   Xaa[1] = Xa[1];
   Xaa[2] = Xa[2];
   Independent(Xaa);

   // ADADdouble parameter
   ADADdouble p = ADADdouble(Xa[0]);
   ADADdouble q = ADADdouble(Xa[1]);
   ADADdouble r = ADADdouble(Xa[2]);

   // ADADdouble dependent variable vector
   CPPAD_TESTVECTOR( ADADdouble ) Yaa(m);

   // CondExp(parameter, parameter, parameter)
   Yaa[0] = CondExp(p, q, r);

   // CondExp(parameter, parameter, variable)
   Yaa[1] = CondExp(p, q, Xaa[2]);

   // CondExp(parameter, variable, parameter)
   Yaa[2] = CondExp(p, Xaa[1], r);

   // CondExp(parameter, variable, variable)
   Yaa[3] = CondExp(p, Xaa[1], Xaa[2]);

   // CondExp(variable, variable, variable)
   Yaa[5] = CondExp(Xaa[0], Xaa[1], Xaa[2]);

   // CondExp(variable, variable, parameter)
   Yaa[4] = CondExp(Xaa[0], Xaa[1], r);

   // CondExp(variable, parameter, variable)
   Yaa[6] =  CondExp(Xaa[0], q, Xaa[2]);

   // CondExp(variable, parameter, parameter)
   Yaa[7] =  CondExp(Xaa[0], q, r);

   // create fa: Xaa -> Yaa function object
   ADFun< ADdouble > fa(Xaa, Yaa);

   // function values
   CPPAD_TESTVECTOR( ADdouble ) Ya(m);
   Ya  = fa.Forward(0, Xa);

   // create f: Xa -> Ya function object
   ADFun<double> f(Xa, Ya);

   // check result of function evaluation
   CPPAD_TESTVECTOR(double) x(n);
   CPPAD_TESTVECTOR(double) y(m);
   x[0] = 1.;
   x[1] = 0.;
   x[2] = -1.;
   y = f.Forward(0, x);
   size_t i;
   for(i = 0; i < m; i++)
   {  // y[i] = CondExp(x[0], x[1], x[2])
      if( x[0] > 0 )
         ok &= (y[i] == x[1]);
      else
         ok &= (y[i] == x[2]);
   }

   // check forward mode derivatives
   CPPAD_TESTVECTOR(double) dx(n);
   CPPAD_TESTVECTOR(double) dy(m);
   dx[0] = 1.;
   dx[1] = 2.;
   dx[2] = 3.;
   dy    = f.Forward(1, dx);
   for(i = 0; i < m; i++)
   {  if( x[0] > 0. )
         ok &= (dy[i] == dx[1]);
      else
         ok &= (dy[i] == dx[2]);
   }

   // calculate Jacobian
   CPPAD_TESTVECTOR(double) J(m * n);
   size_t j;
   for(i = 0; i < m; i++)
   {  for(j = 0; j < n; j++)
         J[i * n + j] = 0.;
      if( x[0] > 0. )
         J[i * n + 1] = 1.;
      else
         J[i * n + 2] = 1.;
   }

   // check reverse mode derivatives
   for(i = 0; i < m; i++)
      dy[i] = double(i);
   dx    = f.Reverse(1, dy);
   double sum;
   for(j = 0; j < n; j++)
   {  sum = 0;
      for(i = 0; i < m; i++)
         sum += dy[i] * J[i * n + j];
      ok &= (sum == dx[j]);
   }

   // forward mode computation of sparsity pattern
   CPPAD_TESTVECTOR(bool) Px(n * n);
   for(i = 0; i < n; i++)
   {  for(j = 0; j < n; j++)
         Px[i * n + j] = false;
      Px[i * n + i] = true;
   }
   CPPAD_TESTVECTOR(bool) Py(m * n);
   Py = f.ForSparseJac(n, Px);
   for(i = 0; i < m; i++)
   {  ok &= Py[ i * n + 0 ] == false;
      ok &= Py[ i * n + 1 ] == true;
      ok &= Py[ i * n + 2 ] == true;
   }

   // reverse mode computation of sparsity pattern
   Py.resize(m * m);
   for(i = 0; i < m; i++)
   {  for(j = 0; j < m; j++)
         Py[i * m + j] = false;
      Py[i * m + i] = true;
   }
   Px.resize(m * n);
   Px = f.RevSparseJac(m, Py);
   for(i = 0; i < m; i++)
   {  for(j = 0; j < n; j++)
         ok &= ( Px[i * n + j] == ( j > 0 ) );
   }

   return ok;
}
bool CondExpADTwo(void)
{  bool ok = true;

   using namespace CppAD;
   size_t n = 3;
   size_t m = 8;

   // ADdouble independent variable vector
   CPPAD_TESTVECTOR( ADdouble ) Xa(n);
   Xa[0] = -1.;
   Xa[1] =  0.;
   Xa[2] =  1.;
   Independent(Xa);

   // use VecAD so that sparsity results are local
   VecAD<double> Va(1);
   ADdouble zero = 0.;
   Va[zero]      = Xa[0];

   // ADdouble independent variable vector
   CPPAD_TESTVECTOR( ADADdouble ) Xaa(n);
   Xaa[0] = ADdouble( Va[zero] );
   Xaa[1] = Xa[1];
   Xaa[2] = Xa[2];
   Independent(Xaa);

   // ADADdouble parameter
   ADADdouble p = ADADdouble(Xa[0]);
   ADADdouble q = ADADdouble(Xa[1]);
   ADADdouble r = ADADdouble(Xa[2]);

   // ADADdouble dependent variable vector
   CPPAD_TESTVECTOR( ADADdouble ) Yaa(m);

   // CondExp(parameter, parameter, parameter)
   Yaa[0] = CondExp(p, q, r);

   // CondExp(parameter, parameter, variable)
   Yaa[1] = CondExp(p, q, Xaa[2]);

   // CondExp(parameter, variable, parameter)
   Yaa[2] = CondExp(p, Xaa[1], r);

   // CondExp(parameter, variable, variable)
   Yaa[3] = CondExp(p, Xaa[1], Xaa[2]);

   // CondExp(variable, variable, variable)
   Yaa[5] = CondExp(Xaa[0], Xaa[1], Xaa[2]);

   // CondExp(variable, variable, parameter)
   Yaa[4] = CondExp(Xaa[0], Xaa[1], r);

   // CondExp(variable, parameter, variable)
   Yaa[6] =  CondExp(Xaa[0], q, Xaa[2]);

   // CondExp(variable, parameter, parameter)
   Yaa[7] =  CondExp(Xaa[0], q, r);

   // create fa: Xaa -> Yaa function object
   ADFun< ADdouble > fa(Xaa, Yaa);

   // function values
   CPPAD_TESTVECTOR( ADdouble ) Ya(m);
   Ya  = fa.Forward(0, Xa);

   // create f: Xa -> Ya function object
   ADFun<double> f(Xa, Ya);

   // check use_VecAD
   ok &= f.use_VecAD();

   // check result of function evaluation
   CPPAD_TESTVECTOR(double) x(n);
   CPPAD_TESTVECTOR(double) y(m);
   x[0] = 1.;
   x[1] = 0.;
   x[2] = -1.;
   y = f.Forward(0, x);
   size_t i;
   for(i = 0; i < m; i++)
   {  // y[i] = CondExp(x[0], x[1], x[2])
      if( x[0] > 0 )
         ok &= (y[i] == x[1]);
      else
         ok &= (y[i] == x[2]);
   }

   // check forward mode derivatives
   CPPAD_TESTVECTOR(double) dx(n);
   CPPAD_TESTVECTOR(double) dy(m);
   dx[0] = 1.;
   dx[1] = 2.;
   dx[2] = 3.;
   dy    = f.Forward(1, dx);
   for(i = 0; i < m; i++)
   {  if( x[0] > 0. )
         ok &= (dy[i] == dx[1]);
      else
         ok &= (dy[i] == dx[2]);
   }

   // calculate Jacobian
   CPPAD_TESTVECTOR(double) J(m * n);
   size_t j;
   for(i = 0; i < m; i++)
   {  for(j = 0; j < n; j++)
         J[i * n + j] = 0.;
      if( x[0] > 0. )
         J[i * n + 1] = 1.;
      else
         J[i * n + 2] = 1.;
   }

   // check reverse mode derivatives
   for(i = 0; i < m; i++)
      dy[i] = double(i);
   dx    = f.Reverse(1, dy);
   double sum;
   for(j = 0; j < n; j++)
   {  sum = 0;
      for(i = 0; i < m; i++)
         sum += dy[i] * J[i * n + j];
      ok &= (sum == dx[j]);
   }

   // forward mode computation of sparsity pattern
   CPPAD_TESTVECTOR(bool) Px(n * n);
   for(i = 0; i < n; i++)
   {  for(j = 0; j < n; j++)
         Px[i * n + j] = false;
      Px[i * n + i] = true;
   }
   CPPAD_TESTVECTOR(bool) Py(m * n);
   Py = f.ForSparseJac(n, Px);
   for(i = 0; i < m; i++)
   {  for(j = 0; j < n; j++)
         // sparsity pattern works for both true and false cases.
         ok &= ( Py[i * n + j] == (j > 0) );
   }

   // reverse mode computation of sparsity pattern
   Py.resize(m * m);
   for(i = 0; i < m; i++)
   {  for(j = 0; j < m; j++)
         Py[i * m + j] = false;
      Py[i * m + i] = true;
   }
   Px.resize(m * n);
   Px = f.RevSparseJac(m, Py);
   for(i = 0; i < m; i++)
   {  for(j = 0; j < n; j++)
         ok &= ( Px[i * n + j] == (j > 0) );
   }

   return ok;
}

} // END empty namespace

bool CondExpAD(void)
{  bool ok = true;
   ok     &= CondExpADOne();
   ok     &= CondExpADTwo();
   return ok;
}
