#-------------------------------------------------------------
#
# Licensed to the Apache Software Foundation (ASF) under one
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# to you under the Apache License, Version 2.0 (the
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# with the License.  You may obtain a copy of the License at
#
#   http://www.apache.org/licenses/LICENSE-2.0
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# KIND, either express or implied.  See the License for the
# specific language governing permissions and limitations
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#-------------------------------------------------------------

# Image Cutout
# Replaces a rectangular section of an image with a constant value.
#
# INPUT PARAMETERS:
# ---------------------------------------------------------------------------------------------
# NAME       TYPE   DEFAULT MEANING
# ---------------------------------------------------------------------------------------------
# img_in     Matrix ---     Input image as 2D matrix with top left corner at [1, 1]
# x          Int    ---     Column index of the top left corner of the rectangle (starting at 1)
# y          Int    ---     Row index of the top left corner of the rectangle (starting at 1)
# width      Int    ---     Width of the rectangle (must be positive)
# height     Int    ---     Height of the rectangle (must be positive)
# fill_value Double ---     The value to set for the rectangle

# RETURN VALUES
# ---------------------------------------------------------------------------------------------
# img_out    Matrix ---     Output image as 2D matrix with top left corner at [1, 1]
# ---------------------------------------------------------------------------------------------

m_img_cutout = function(Matrix[Double] img_in, Integer x, Integer y, Integer width, Integer height, Double fill_value) return (Matrix[Double] img_out) {
  rows = nrow(img_in)
  cols = ncol(img_in)

  if (width < 1 | height < 1) {
    print("Invalid width or height. Returning input")
    img_out = img_in
  } else {
    end_x = x + width - 1
    end_y = y + height - 1

    start_x = max(1, x)
    start_y = max(1, y)
    end_x = min(cols, end_x)
    end_y = min(rows, end_y)

    img_out = matrix(img_in, rows=rows, cols=cols)
    img_out[start_y:end_y, start_x:end_x] = matrix(fill_value, rows=(end_y-start_y+1), cols=(end_x-start_x+1))
  }
}
