/*=========================================================================
 *
 *  Copyright NumFOCUS
 *
 *  Licensed under the Apache License, Version 2.0 (the "License");
 *  you may not use this file except in compliance with the License.
 *  You may obtain a copy of the License at
 *
 *         https://www.apache.org/licenses/LICENSE-2.0.txt
 *
 *  Unless required by applicable law or agreed to in writing, software
 *  distributed under the License is distributed on an "AS IS" BASIS,
 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *  See the License for the specific language governing permissions and
 *  limitations under the License.
 *
 *=========================================================================*/

#include "itkFEMLinearSystemWrapperItpack.h"
#include <iostream>

/* Testing for linear system wrappers */
int
itkFEMLinearSystemWrapperItpackTest2(int argc, char * argv[])
{
  /* declare wrapper */
  itk::fem::LinearSystemWrapperItpack it;

  /* system parameters */
  unsigned int N = 3;
  unsigned int nMatrices = 1;
  unsigned int nVectors = 1;
  unsigned int nSolutions = 1;

  /* Set up the system */
  it.SetSystemOrder(N);
  it.SetNumberOfMatrices(nMatrices);
  it.SetNumberOfVectors(nVectors);
  it.SetNumberOfSolutions(nSolutions);

  /* Set max non zeros in any matrix */
  it.SetMaximumNonZeroValuesInMatrix(9);
  /* Initialize memory */
  for (unsigned int i = 0; i < nMatrices; ++i)
  {
    it.InitializeMatrix(i);
  }
  for (unsigned int i = 0; i < nVectors; ++i)
  {
    it.InitializeVector(i);
  }
  for (unsigned int i = 0; i < nSolutions; ++i)
  {
    it.InitializeSolution(i);
  }

  /*     matrix 0
   * |11  0  0|
   * | 0 22  0|
   * | 0  0 33|
   */
  it.SetMatrixValue(0, 0, 11, 0);
  it.SetMatrixValue(1, 1, 22, 0);
  it.SetMatrixValue(2, 2, 33, 0);

  /* print matrix 0 */
  std::cout << "Matrix 0" << std::endl;
  for (unsigned int i = 0; i < N; ++i)
  {
    for (unsigned int j = 0; j < N; ++j)
    {
      std::cout << it.GetMatrixValue(i, j, 0) << ' ';
    }
    std::cout << std::endl;
  }
  std::cout << std::endl;

  /* Vector 0 = [1 2 3 ] */
  it.SetVectorValue(0, 1, 0);
  it.SetVectorValue(1, 2, 0);
  it.SetVectorValue(2, 3, 0);

  /* print Vector 0 */
  std::cout << "Vector 0" << std::endl;
  for (unsigned int i = 0; i < N; ++i)
  {
    std::cout << it.GetVectorValue(i, 0) << ' ';
  }
  std::cout << std::endl << std::endl;

  if (argc > 1)
  {
    int method = std::stoi(argv[1]);

    switch (method)
    {
      case 0:
        it.JacobianConjugateGradient();
        break;
      case 1:
        it.JacobianSemiIterative();
        break;
      case 2:
        it.SuccessiveOverrelaxation();
        break;
      case 3:
        it.SymmetricSuccessiveOverrelaxationConjugateGradient();
        break;
      case 4:
        it.SymmetricSuccessiveOverrelaxationSuccessiveOverrelaxation();
        break;
      case 5:
        it.ReducedSystemConjugateGradient();
        break;
      case 6:
        it.ReducedSystemSemiIteration();
        break;
    }
  }

  /* solve system */
  std::cout << "Solve for x in: Matrix 0 * x = Vector 0" << std::endl;
  it.Solve();
  std::cout << "Solution 0" << std::endl;
  for (unsigned int i = 0; i < N; ++i)
  {
    std::cout << it.GetSolutionValue(i, 0) << ' ';
  }
  std::cout << std::endl << std::endl;

  /* destroy matrix,vector,solution */
  it.DestroyMatrix(0);
  it.DestroyVector(0);
  it.DestroySolution(0);

  std::cout << "Done." << std::endl;

  return EXIT_SUCCESS;
}
