/* VEquiRect.cpp */

/*
remap
Copyright (C) 2006 Fabrice Ducos, fabrice.ducos@icare.univ-lille1.fr

This program 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 2
of the License, or (at your option) any later version.

This program 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 this program; if not, write to the Free Software
Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
*/

#include "VEquiRect.h"

VEquiRect::VEquiRect(coord_type latitude_orig, coord_type longitude_orig, double resolution /* in km/pixel */, int nrows, int ncols) { 
  PDEBUG;

  const coord_type MIN_LAT = -90.;
  const coord_type MAX_LAT = +90.;
  const coord_type MIN_LON = -180.;
  const coord_type MAX_LON = +180.;

  try {
    lat_ = new coord_type[nrows*ncols];
    lon_ = new coord_type[nrows*ncols];
    time_ = new time_type[nrows*ncols];
  }
  catch (std::bad_alloc &e) {
    Debug(std::cerr << APPNAME << ": " << __PRETTY_FUNCTION__ << ": " << e.what() << endl;);
    destroy();
    throw;
  }
  catch (...) {
    std::cerr << APPNAME << ": internal error: unexpected exception" << endl;
    destroy();
    throw;
  }

  assert(dimensions_.size() == 0);
  dimensions_.push_back(nrows);
  dimensions_.push_back(ncols);

  const coord_type stride = resolution*DEGREES_PER_KM; // in degrees per pixel
  const coord_type lat_stride = stride;
  const coord_type lon_stride = stride;

  for (int irow = 0 ; irow < nrows ; ++irow) {
    for (int icol = 0 ; icol < ncols ; ++icol) {
      const coord_type lat = latitude_orig - irow*lat_stride;
      const coord_type lon = longitude_orig + icol*lon_stride;
      const int ipixel = irow*ncols + icol;
      if ((MIN_LAT <= lat && lat <= MAX_LAT) == false || (MIN_LON <= lon && lon <= MAX_LON) == false) {
	lat_[ipixel] = g_coord_fill_value;
	lon_[ipixel] = g_coord_fill_value;
	continue;
      }
      lat_[ipixel] = lat;
      lon_[ipixel] = lon;
      time_[ipixel] = INFINITY;
    }
  }
  
}

void
VEquiRect::destroy() {
  PDEBUG;

  if (lat_) {
    delete[] lat_;
    lat_ = NULL;
  }

  if (lon_) {
    delete[] lon_;
    lon_ = NULL;
  }

  if (time_) {
    delete[] time_;
    time_ = NULL;
  }
}


VEquiRect::~VEquiRect() { 
  PDEBUG;
  destroy();
}

const double VEquiRect::EARTH_RADIUS_KM = 6370.949;
const double VEquiRect::DEGREES_PER_KM = 180./(M_PI*VEquiRect::EARTH_RADIUS_KM);