/*******************************************************************************
 *
 * TRIQS: a Toolbox for Research in Interacting Quantum Systems
 *
 * Copyright (C) 2011 by O. Parcollet
 *
 * TRIQS is free software: you can redistribute it and/or modify it under the
 * terms of the GNU General Public License as published by the Free Software
 * Foundation, either version 3 of the License, or (at your option) any later
 * version.
 *
 * TRIQS is distributed in the hope that it will be useful, but WITHOUT ANY
 * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
 * FOR A PARTICULAR PURPOSE. See the GNU General Public License for more
 * details.
 *
 * You should have received a copy of the GNU General Public License along with
 * TRIQS. If not, see <http://www.gnu.org/licenses/>.
 *
 ******************************************************************************/
#include "./common.hpp"
#include "./src/matrix.hpp"
#include "./src/asserts.hpp"
#include "./src/linalg/matmul.hpp"
#include <iostream>
using namespace triqs::arrays;

template<typename T, typename O1, typename O2, typename O3> void test(O1 o1, O2 o2, O3 o3,bool all =false)  { 
 matrix<T> M1(2,3, o1);
 matrix<T> M2(3,4, o2);
 matrix<T> M3(o3), M4;
 for (int i =0; i<2; ++i)
  for (int j=0; j<3; ++j)
  { M1(i,j) =  i +j ; }
 for (int i =0; i<3; ++i)
  for (int j=0; j<4; ++j)
  { M2(i,j) = 1 + i -j ; }

 // The central instruction : note that matmul returns a lazy object 
 // that has ImmutableArray interface, and defines a specialized version assignment
 // As a result this is equivalent to matmul_with_lapack(M1,M2,M3) : there is NO intermediate copy.
 M3 = matmul(M1,M2);

 M4 = M3; 
 M4() = 0;
 for (int i =0; i<2; ++i)
  for (int k=0; k<3; ++k)
  for (int j=0; j<4; ++j)
   M4(i,j) += M1(i,k)*M2(k,j);
 assert_all_close(M4,M3, 1.e-13,false);

 // recheck gemm_generic 
 blas::gemm_generic(1, M1, M2, 0, M4);
 assert_all_close(M4,M3, 1.e-13,false);

 if (all) { 
  std::cerr<<"M1 = "<<M1<<std::endl;
  std::cerr<<"M2 = "<<M2<<std::endl;
  std::cerr<<"M3 = "<<M3<<std::endl;
  std::cerr<<"M4 = "<< matrix<T>(matmul(M1,M2)) <<std::endl;
  std::cerr<<"M5 = "<< matrix<T>(matmul(M1,M2)) <<std::endl;

  for (int i =0; i<2; ++i)
   for (int j=0; j<2; ++j)
    M3(i,j) = matmul(M1,M2)(i,j); //[mini_vector<int,2>(i,j)];
 }

 std::cerr<<"M3 = "<<M3<<std::endl<<"----------------"<<std::endl;

}

template<typename T> void all_tests() { 
 test<T>(C_LAYOUT      , C_LAYOUT      , C_LAYOUT      , true);
 test<T>(C_LAYOUT      , C_LAYOUT      , FORTRAN_LAYOUT);
 test<T>(C_LAYOUT      , FORTRAN_LAYOUT, FORTRAN_LAYOUT);
 test<T>(C_LAYOUT      , FORTRAN_LAYOUT, C_LAYOUT      );
 test<T>(FORTRAN_LAYOUT, FORTRAN_LAYOUT, FORTRAN_LAYOUT);
 test<T>(FORTRAN_LAYOUT, C_LAYOUT      , FORTRAN_LAYOUT);
 test<T>(FORTRAN_LAYOUT, FORTRAN_LAYOUT, C_LAYOUT      );
 test<T>(FORTRAN_LAYOUT, C_LAYOUT      , C_LAYOUT      );
}

int main(int argc, char **argv) {
 all_tests<double>();
 all_tests<std::complex<double>>();
 all_tests<long>();
 return 0;
}