#include <cctk.h>
#include <cctk_Parameters.h>

#include <loopcontrol.h>

#include <algorithm>
#include <cassert>
#include <cmath>
#include <cstdlib>
#include <iostream>

#include "operator_prototypes_3d.hh"
#include "typeprops.hh"

using namespace std;



namespace CarpetLib {


  
#define SRCIND3(i,j,k)                                  \
  index3 (srcioff + (i), srcjoff + (j), srckoff + (k),  \
          srcipadext, srcjpadext, srckpadext,           \
          srciext, srcjext, srckext)
#define DSTIND3(i,j,k)                                  \
  index3 (dstioff + (i), dstjoff + (j), dstkoff + (k),  \
          dstipadext, dstjpadext, dstkpadext,           \
          dstiext, dstjext, dstkext)
  
  
  
  template <typename T>
  void
  restrict_3d_rf2 (T const * restrict const src,
                   ivect3 const & restrict srcpadext,
                   ivect3 const & restrict srcext,
                   T * restrict const dst,
                   ivect3 const & restrict dstpadext,
                   ivect3 const & restrict dstext,
                   ibbox3 const & restrict srcbbox,
                   ibbox3 const & restrict dstbbox,
                   ibbox3 const & restrict,
                   ibbox3 const & restrict regbbox,
                   void * extraargs)
  {
    DECLARE_CCTK_PARAMETERS;
    
    assert (not extraargs);
    
    if (any (srcbbox.stride() >= regbbox.stride() or
             dstbbox.stride() != regbbox.stride()))
    {
      CCTK_WARN (0, "Internal error: strides disagree");
    }
    
    if (any (reffact2 * srcbbox.stride() != dstbbox.stride())) {
      CCTK_WARN (0, "Internal error: destination strides are not twice the source strides");
    }
    
    // This could be handled, but is likely to point to an error
    // elsewhere
    if (regbbox.empty()) {
      CCTK_WARN (0, "Internal error: region extent is empty");
    }
    
    if (not regbbox.is_contained_in(srcbbox) or
        not regbbox.is_contained_in(dstbbox))
    {
      cerr << "srcbbox: " << srcbbox << endl
           << "dstbbox: " << dstbbox << endl
           << "regbbox: " << regbbox << endl;
      CCTK_WARN (0, "Internal error: region extent is not contained in array extent");
    }
    
    
    
    ivect3 const regext = regbbox.shape() / regbbox.stride();
    assert (all ((regbbox.lower() - srcbbox.lower()) % srcbbox.stride() == 0));
    ivect3 const srcoff =
      (regbbox.lower() - srcbbox.lower()) / srcbbox.stride();
    assert (all ((regbbox.lower() - dstbbox.lower()) % dstbbox.stride() == 0));
    ivect3 const dstoff =
      (regbbox.lower() - dstbbox.lower()) / dstbbox.stride();
    
    
    
    int const srcipadext = srcpadext[0];
    int const srcjpadext = srcpadext[1];
    int const srckpadext = srcpadext[2];
    
    int const dstipadext = dstpadext[0];
    int const dstjpadext = dstpadext[1];
    int const dstkpadext = dstpadext[2];
    
    int const srciext = srcext[0];
    int const srcjext = srcext[1];
    int const srckext = srcext[2];
    
    int const dstiext = dstext[0];
    int const dstjext = dstext[1];
    int const dstkext = dstext[2];
    
    int const regiext = regext[0];
    int const regjext = regext[1];
    int const regkext = regext[2];
    
    int const srcioff = srcoff[0];
    int const srcjoff = srcoff[1];
    int const srckoff = srcoff[2];
    
    int const dstioff = dstoff[0];
    int const dstjoff = dstoff[1];
    int const dstkoff = dstoff[2];
    
    
    
    if (not use_loopcontrol_in_operators) {
      
      // Loop over coarse region
      for (int k=0; k<regkext; ++k) {
        for (int j=0; j<regjext; ++j) {
          for (int i=0; i<regiext; ++i) {
            
            dst [DSTIND3(i, j, k)] = src [SRCIND3(2*i, 2*j, 2*k)];
            
          }
        }
      }
      
    } else {
      
      // Loop over coarse region
#pragma omp parallel
      CCTK_LOOP3(restrict_3d_rf2,
                 i,j,k, 0,0,0, regiext,regjext,regkext,
                 dstipadext,dstjpadext,dstkpadext)
      {
        
        dst [DSTIND3(i, j, k)] = src [SRCIND3(2*i, 2*j, 2*k)];
        
      } CCTK_ENDLOOP3(restrict_3d_rf2);
      
    }
    
  }
  
  
  
#define TYPECASE(N,T)                                   \
  template                                              \
  void                                                  \
  restrict_3d_rf2 (T const * restrict const src,        \
                   ivect3 const & restrict srcpadext,   \
                   ivect3 const & restrict srcext,      \
                   T * restrict const dst,              \
                   ivect3 const & restrict dstpadext,   \
                   ivect3 const & restrict dstext,      \
                   ibbox3 const & restrict srcbbox,     \
                   ibbox3 const & restrict dstbbox,     \
                   ibbox3 const & restrict,             \
                   ibbox3 const & restrict regbbox,     \
                   void * extraargs);
#include "typecase.hh"
#undef TYPECASE
  
  
  
} // namespace CarpetLib