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#include "gdal_algorithms.hpp"
#include "gdal_common.hpp"
#include "gdal_dataset.hpp"
#include "gdal_layer.hpp"
#include "gdal_rasterband.hpp"
#include "utils/number_list.hpp"

namespace node_gdal {

void Algorithms::Initialize(Local<Object> target) {
  Nan::SetMethod(target, "fillNodata", fillNodata);
  Nan::SetMethod(target, "contourGenerate", contourGenerate);
  Nan::SetMethod(target, "sieveFilter", sieveFilter);
  Nan::SetMethod(target, "checksumImage", checksumImage);
  Nan::SetMethod(target, "polygonize", polygonize);
}

/**
 * Fill raster regions by interpolation from edges.
 *
 * @throws Error
 * @method fillNodata
 * @static
 * @for gdal
 * @param {Object} options
 * @param {gdal.RasterBand} options.src This band to be updated in-place.
 * @param {gdal.RasterBand} [options.mask] Mask band
 * @param {Number} options.searchDist The maximum distance (in pixels) that the
 * algorithm will search out for values to interpolate.
 * @param {integer} [options.smoothingIterations=0] The number of 3x3 average
 * filter smoothing iterations to run after the interpolation to dampen
 * artifacts.
 */
NAN_METHOD(Algorithms::fillNodata) {
  Nan::HandleScope scope;

  Local<Object> obj;
  RasterBand *src;
  RasterBand *mask = NULL;
  double search_dist;
  int smooth_iterations = 0;

  NODE_ARG_OBJECT(0, "options", obj);

  NODE_WRAPPED_FROM_OBJ(obj, "src", RasterBand, src);
  NODE_WRAPPED_FROM_OBJ_OPT(obj, "mask", RasterBand, mask);
  NODE_DOUBLE_FROM_OBJ(obj, "searchDist", search_dist);
  NODE_INT_FROM_OBJ_OPT(obj, "smoothIterations", smooth_iterations)

  CPLErr err =
    GDALFillNodata(src->get(), mask ? mask->get() : NULL, search_dist, 0, smooth_iterations, NULL, NULL, NULL);

  if (err) {
    NODE_THROW_CPLERR(err);
    return;
  }

  return;
}

/**
 * Create vector contours from raster DEM.
 *
 * This algorithm will generate contour vectors for the input raster band on the
 * requested set of contour levels. The vector contours are written to the
 * passed in vector layer. Also, a NODATA value may be specified to identify
 * pixels that should not be considered in contour line generation.
 *
 * @throws Error
 * @method contourGenerate
 * @static
 * @for gdal
 * @param {Object} options
 * @param {gdal.RasterBand} options.src
 * @param {gdal.Layer} options.dst
 * @param {Number} [options.offset=0] The "offset" relative to which contour
 * intervals are applied. This is normally zero, but could be different. To
 * generate 10m contours at 5, 15, 25, ... the offset would be 5.
 * @param {Number} [options.interval=100] The elevation interval between
 * contours generated.
 * @param {Number[]} [options.fixedLevels] A list of fixed contour levels at
 * which contours should be generated. Overrides interval/base options if set.
 * @param {Number} [options.nodata] The value to use as a "nodata" value. That
 * is, a pixel value which should be ignored in generating contours as if the
 * value of the pixel were not known.
 * @param {integer} [options.idField] A field index to indicate where a unique
 * id should be written for each feature (contour) written.
 * @param {integer} [options.elevField] A field index to indicate where the
 * elevation value of the contour should be written.
 */
NAN_METHOD(Algorithms::contourGenerate) {
  Nan::HandleScope scope;

  Local<Object> obj;
  Local<Value> prop;
  RasterBand *src;
  Layer *dst;
  double interval = 100, base = 0;
  double *fixed_levels = NULL;
  DoubleList fixed_level_array;
  int n_fixed_levels = 0;
  int use_nodata = 0;
  double nodata = 0;
  int id_field = -1, elev_field = -1;

  NODE_ARG_OBJECT(0, "options", obj);

  NODE_WRAPPED_FROM_OBJ(obj, "src", RasterBand, src);
  NODE_WRAPPED_FROM_OBJ(obj, "dst", Layer, dst);
  NODE_INT_FROM_OBJ_OPT(obj, "idField", id_field);
  NODE_INT_FROM_OBJ_OPT(obj, "elevField", elev_field);
  NODE_DOUBLE_FROM_OBJ_OPT(obj, "interval", interval);
  NODE_DOUBLE_FROM_OBJ_OPT(obj, "offset", base);
  if (Nan::HasOwnProperty(obj, Nan::New("fixedLevels").ToLocalChecked()).FromMaybe(false)) {
    if (fixed_level_array.parse(Nan::Get(obj, Nan::New("fixedLevels").ToLocalChecked()).ToLocalChecked())) {
      return; // error parsing double list
    } else {
      fixed_levels = fixed_level_array.get();
      n_fixed_levels = fixed_level_array.length();
    }
  }
  if (Nan::HasOwnProperty(obj, Nan::New("nodata").ToLocalChecked()).FromMaybe(false)) {
    prop = Nan::Get(obj, Nan::New("nodata").ToLocalChecked()).ToLocalChecked();
    if (prop->IsNumber()) {
      use_nodata = 1;
      nodata = Nan::To<double>(prop).ToChecked();
    } else if (!prop->IsNull() && !prop->IsUndefined()) {
      Nan::ThrowTypeError("nodata property must be a number");
    }
  }

  CPLErr err = GDALContourGenerate(
    src->get(),
    interval,
    base,
    n_fixed_levels,
    fixed_levels,
    use_nodata,
    nodata,
    dst->get(),
    id_field,
    elev_field,
    NULL,
    NULL);

  if (err) {
    NODE_THROW_CPLERR(err);
    return;
  }

  return;
}

/**
 * Removes small raster polygons.
 *
 * @throws Error
 * @method sieveFilter
 * @static
 * @for gdal
 * @param {Object} options
 * @param {gdal.RasterBand} options.src
 * @param {gdal.RasterBand} options.dst Output raster band. It may be the same
 * as src band to update the source in place.
 * @param {gdal.RasterBand} [options.mask] All pixels in the mask band with a
 * value other than zero will be considered suitable for inclusion in polygons.
 * @param {Number} options.threshold Raster polygons with sizes smaller than
 * this will be merged into their largest neighbour.
 * @param {integer} [options.connectedness=4] Either 4 indicating that diagonal
 * pixels are not considered directly adjacent for polygon membership purposes
 * or 8 indicating they are.
 */
NAN_METHOD(Algorithms::sieveFilter) {
  Nan::HandleScope scope;

  Local<Object> obj;
  RasterBand *src;
  RasterBand *dst;
  RasterBand *mask = NULL;
  int threshold;
  int connectedness = 4;

  NODE_ARG_OBJECT(0, "options", obj);

  NODE_WRAPPED_FROM_OBJ(obj, "src", RasterBand, src);
  NODE_WRAPPED_FROM_OBJ(obj, "dst", RasterBand, dst);
  NODE_WRAPPED_FROM_OBJ_OPT(obj, "mask", RasterBand, mask);
  NODE_INT_FROM_OBJ(obj, "threshold", threshold);
  NODE_INT_FROM_OBJ_OPT(obj, "connectedness", connectedness);

  if (connectedness != 4 && connectedness != 8) {
    Nan::ThrowError("connectedness option must be 4 or 8");
    return;
  }

  CPLErr err =
    GDALSieveFilter(src->get(), mask ? mask->get() : NULL, dst->get(), threshold, connectedness, NULL, NULL, NULL);

  if (err) {
    NODE_THROW_CPLERR(err);
    return;
  }

  return;
}

/**
 * Compute checksum for image region.
 *
 * @throws Error
 * @method checksumImage
 * @static
 * @for gdal
 * @param {gdal.RasterBand} src
 * @param {integer} [x=0]
 * @param {integer} [y=0]
 * @param {integer} [w=src.width]
 * @param {integer} [h=src.height]
 * @return integer
 */
NAN_METHOD(Algorithms::checksumImage) {
  Nan::HandleScope scope;

  RasterBand *src;
  int x = 0, y = 0, w, h, bandw, bandh;

  NODE_ARG_WRAPPED(0, "src", RasterBand, src);

  w = bandw = src->get()->GetXSize();
  h = bandh = src->get()->GetYSize();

  NODE_ARG_INT_OPT(1, "x", x);
  NODE_ARG_INT_OPT(2, "y", y);
  NODE_ARG_INT_OPT(3, "xSize", w);
  NODE_ARG_INT_OPT(4, "ySize", h);

  if (x < 0 || y < 0 || x >= bandw || y >= bandh) {
    Nan::ThrowRangeError("offset invalid for given band");
    return;
  }
  if (w < 0 || h < 0 || w > bandw || h > bandh) {
    Nan::ThrowRangeError("x and y size must be smaller than band dimensions and greater than 0");
    return;
  }
  if (x + w - 1 >= bandw || y + h - 1 >= bandh) {
    Nan::ThrowRangeError("given range is outside bounds of given band");
    return;
  }

  int checksum = GDALChecksumImage(src->get(), x, y, w, h);

  info.GetReturnValue().Set(Nan::New<Integer>(checksum));
}

/**
 * Creates vector polygons for all connected regions of pixels in the raster
 * sharing a common pixel value. Each polygon is created with an attribute
 * indicating the pixel value of that polygon. A raster mask may also be
 * provided to determine which pixels are eligible for processing.
 *
 * @throws Error
 * @method polygonize
 * @static
 * @for gdal
 * @param {Object} options
 * @param {gdal.RasterBand} options.src
 * @param {gdal.Layer} options.dst
 * @param {gdal.RasterBand} [options.mask]
 * @param {integer} options.pixValField The attribute field index indicating the
 * feature attribute into which the pixel value of the polygon should be
 * written.
 * @param {integer} [options.connectedness=4] Either 4 indicating that diagonal
 * pixels are not considered directly adjacent for polygon membership purposes
 * or 8 indicating they are.
 * @param {Boolean} [options.useFloats=false] Use floating point buffers instead
 * of int buffers.
 */
NAN_METHOD(Algorithms::polygonize) {
  Nan::HandleScope scope;

  Local<Object> obj;
  RasterBand *src;
  RasterBand *mask = NULL;
  Layer *dst;
  int connectedness = 4;
  int pix_val_field = 0;
  char **papszOptions = NULL;

  NODE_ARG_OBJECT(0, "options", obj);

  NODE_WRAPPED_FROM_OBJ(obj, "src", RasterBand, src);
  NODE_WRAPPED_FROM_OBJ(obj, "dst", Layer, dst);
  NODE_WRAPPED_FROM_OBJ_OPT(obj, "mask", RasterBand, mask);
  NODE_INT_FROM_OBJ_OPT(obj, "connectedness", connectedness)
  NODE_INT_FROM_OBJ(obj, "pixValField", pix_val_field);

  if (connectedness == 8) {
    papszOptions = CSLSetNameValue(papszOptions, "8CONNECTED", "8");
  } else if (connectedness != 4) {
    Nan::ThrowError("connectedness must be 4 or 8");
    return;
  }

  CPLErr err;
  if (
    Nan::HasOwnProperty(obj, Nan::New("useFloats").ToLocalChecked()).FromMaybe(false) &&
    Nan::To<bool>(Nan::Get(obj, Nan::New("useFloats").ToLocalChecked()).ToLocalChecked()).ToChecked()) {
    err = GDALFPolygonize(
      src->get(),
      mask ? mask->get() : NULL,
      reinterpret_cast<OGRLayerH>(dst->get()),
      pix_val_field,
      papszOptions,
      NULL,
      NULL);
  } else {
    err = GDALPolygonize(
      src->get(),
      mask ? mask->get() : NULL,
      reinterpret_cast<OGRLayerH>(dst->get()),
      pix_val_field,
      papszOptions,
      NULL,
      NULL);
  }

  if (papszOptions) CSLDestroy(papszOptions);

  if (err) {
    NODE_THROW_CPLERR(err);
    return;
  }

  return;
}

} // namespace node_gdal