/*
 * Copyright (c) 2008-2018 the MRtrix3 contributors.
 *
 * This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, you can obtain one at http://mozilla.org/MPL/2.0/
 *
 * MRtrix3 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.
 *
 * For more details, see http://www.mrtrix.org/
 */


#include "command.h"
#include "progressbar.h"
#include "datatype.h"


#include "image.h"
#include "fixel/legacy/image.h"
#include "fixel/legacy/fixel_metric.h"
#include "image_helpers.h"
#include "algo/threaded_loop.h"
using MR::Fixel::Legacy::FixelMetric;

using namespace MR;
using namespace App;

void usage ()
{
  AUTHOR = "David Raffelt (david.raffelt@florey.edu.au) and Robert E. Smith (robert.smith@florey.edu.au)";

  SYNOPSIS = "Compare two fixel images for differences, within specified tolerance";

  ARGUMENTS
  + Argument ("data1", "a fixel image.").type_image_in ()
  + Argument ("data2", "another fixel image.").type_image_in ()
  + Argument ("tolerance", "the amount of signal difference to consider acceptable").type_float (0.0);
}


void run ()
{
  Fixel::Legacy::Image<FixelMetric> buffer1 (argument[0]);
  Fixel::Legacy::Image<FixelMetric> buffer2 (argument[1]);
  check_dimensions (buffer1, buffer2);
  for (size_t i = 0; i < buffer1.ndim(); ++i) {
    if (std::isfinite (buffer1.spacing(i)))
      if (buffer1.spacing(i) != buffer2.spacing(i))
        throw Exception ("images \"" + buffer1.name() + "\" and \"" + buffer2.name() + "\" do not have matching voxel spacings " +
                                       str(buffer1.spacing(i)) + " vs " + str(buffer2.spacing(i)));
  }
  for (size_t i  = 0; i < 3; ++i) {
    for (size_t j  = 0; j < 4; ++j) {
      if (abs (buffer1.transform()(i,j) - buffer2.transform()(i,j)) > 0.001)
        throw Exception ("images \"" + buffer1.name() + "\" and \"" + buffer2.name() + "\" do not have matching header transforms "
                         + "\n" + str(buffer1.transform().matrix()) + "vs \n " + str(buffer2.transform().matrix()) + ")");
    }
  }

  double tol = argument[2];

  ThreadedLoop (buffer1)
    .run ([&tol] (decltype(buffer1)& a, decltype(buffer2)& b) {
       if (a.value().size() != b.value().size())
         throw Exception ("the fixel images do not have corresponding fixels in all voxels");
       // For each fixel
       for (size_t fixel = 0; fixel != a.value().size(); ++fixel) {
         // Check value
         if (abs (a.value()[fixel].value - b.value()[fixel].value) > tol)
           throw Exception ("images \"" + a.name() + "\" and \"" + b.name() + "\" do not match fixel value within specified precision of " + str(tol)
               + " (" + str(a.value()[fixel].value) + " vs " + str(b.value()[fixel].value) + ")");
         // Check size
         if (abs (a.value()[fixel].size - b.value()[fixel].size) > tol)
           throw Exception ("images \"" + a.name() + "\" and \"" + b.name() + "\" do not match fixel size within specified precision of " + str(tol)
               + " (" + str(a.value()[fixel].size) + " vs " + str(b.value()[fixel].size) + ")");
         // Check Direction
         for (size_t dim = 0; dim < 3; ++dim) {
           if (abs (a.value()[fixel].dir[dim] - b.value()[fixel].dir[dim]) > tol)
             throw Exception ("images \"" + a.name() + "\" and \"" + b.name() + "\" do not match fixel direction within specified precision of " + str(tol)
                 + " (" + str(a.value()[fixel].dir[dim]) + " vs " + str(b.value()[fixel].dir[dim]) + ")");
         }
       }
     }, buffer1, buffer2);


  CONSOLE ("data checked OK");
}
